阅读说明：本技术 用于动态tdd系统的冲突处理机制 (Conflict handling mechanism for dynamic TDD systems ) 是由 郝辰曦 张煜 武良明 魏超 陈万士 于 2018-06-08 设计创作，主要内容包括：描述了用于无线通信的方法、系统和设备。概括而言,所描述的技术提供用于传送上行链路准许和信道状态信息参考信号(CSI-RS)触发。无线设备可以针对载波的时隙来识别CSI-RS与上行链路数据之间的未决冲突。无线设备可以确定针对CSI-RS和上行链路数据的通信配置,使得不发生冲突。所确定的针对CSI-RS的通信配置可以包括：延迟冲突的信号中的一个信号,仅发送冲突的信号中的一个信号并且抑制另一个信号,或者将时隙重新配置为使得两个信号都能够被成功地发送。另外,UE和基站可以基于所确定的通信配置来确定CSI报告配置。(Methods, systems, and devices for wireless communication are described. In general, the described techniques provide for transmitting uplink grants and channel state information reference signal (CSI-RS) triggers. The wireless device may identify a pending collision between the CSI-RS and uplink data for a time slot of the carrier. The wireless device may determine communication configurations for the CSI-RS and uplink data such that no collision occurs. The determined communication configuration for the CSI-RS may include: delaying one of the colliding signals, transmitting only one of the colliding signals and suppressing the other signal, or reconfiguring the time slot so that both signals can be successfully transmitted. In addition, the UE and the base station may determine a CSI reporting configuration based on the determined communication configuration.)

1. A method for wireless communication at a User Equipment (UE), comprising:

receiving a channel state information reference signal (CSI-RS) trigger and an uplink grant;

identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant;

determining a communication configuration for the CSI-RS and the uplink data based at least in part on the pending conflict;

identifying a CSI reporting trigger; and

determining a CSI reporting configuration based at least in part on the communication configuration and the CSI reporting trigger.

2. The method of claim 1, wherein determining the communication configuration for the CSI-RS and the uplink data further comprises:

refraining from transmitting the uplink data in the time slot;

receiving the CSI-RS in the slot; and

receiving a signal indicating that the uplink grant is not transmitted and requesting retransmission of the uplink data.

3. The method of claim 1, wherein determining the communication configuration for the CSI-RS and the uplink data further comprises:

determining that CSI-RS for the slot has been discontinued by a base station; and

transmitting the uplink data in the time slot.

4. The method of claim 3, further comprising:

refraining from performing measurements corresponding to the suppressed CSI-RS for the slot on the carrier.

5. The method of claim 3, further comprising:

refraining from transmitting a CSI report associated with the suppressed CSI-RS.

6. The method of claim 3, further comprising:

transmitting a CSI report associated with the CSI reporting trigger for the carrier based at least in part on measurements of CSI-RSs performed prior to the time slot.

7. The method of claim 3, further comprising:

determining that the carrier is one component carrier of a plurality of configured component carriers;

identifying a CSI-RS received in the slot on at least one second component carrier of the plurality of configured component carriers;

performing measurements of the identified CSI-RS received in the slot on the at least one second component carrier; and

sending a CSI report for the second component carrier based at least in part on the measurements for the CSI-RS received in the slot on the at least one second component carrier.

8. The method of claim 1, further comprising:

determining a backoff period comprising one or more time slots;

receiving the CSI-RS in the slot; and

transmitting the uplink data in a second slot determined by applying the backoff period from the slot.

9. The method of claim 1, further comprising:

determining a backoff period comprising one or more time slots;

transmitting the uplink data in the time slot; and

receiving the CSI-RS in a second slot determined by applying the backoff period from the slot.

10. The method of claim 8, wherein:

determining the backoff period further comprises:

receiving a set of backoff periods via a first downlink control signal; the method further comprises the following steps:

receiving a second downlink control signal corresponding to the CSI-RS, the uplink data, or neither the uplink grant nor the CSI-RS; and

selecting one of the set of backoff periods based at least in part on the received second downlink control signal.

11. The method of claim 1, further comprising:

determining the CSI-RS resource amount;

wherein determining the communication configuration comprises:

determining a number of downlink symbols and a number of uplink symbols within the slot for receiving the CSI-RS and transmitting the uplink data in the slot;

performing rate matching of the uplink data based at least in part on the number of uplink symbols; and

receiving the CSI-RS using the downlink symbol in the slot, and transmitting the uplink data using the uplink symbol in the slot.

12. The method of claim 1, further comprising:

identifying a downlink control channel received via a first portion of the timeslot; and

receiving the CSI-RS multiplexed into the first portion of the time slot using one of Frequency Division Multiplexing (FDM), Code Division Multiplexing (CDM), or Time Division Multiplexing (TDM).

13. The method of claim 1, further comprising:

determining that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period; and

performing measurements of the CSI-RS received in a second slot corresponding to the first backoff period from the slot.

14. The method of claim 13, further comprising:

determining that a reporting delay initiated from the CSI-RS trigger does not exceed the second time slot by at least a threshold number of time slots;

determining a second backoff period comprising the first backoff period or a reporting delay; and

transmitting a CSI report in a third time slot corresponding to the second backoff period from the time slot in which the CSI report is triggered.

15. The method of claim 14, wherein determining the second backoff period further comprises:

receiving a second set of backoff periods in the first downlink control signal;

the method further comprises the following steps:

receiving a second downlink control signal, wherein the second downlink control signal corresponds to one of: the uplink grant, the CSI-RS trigger, or a downlink control signal separate from the uplink grant and the CSI-RS trigger; and

selecting one of the second set of backoff periods based at least in part on the received second downlink control signal.

16. The method of claim 15, wherein at least one of the first downlink control signal and the second downlink control signal comprises Downlink Control Information (DCI), a Media Access Control (MAC) Control Element (CE), or a Radio Resource Control (RRC) message.

17. The method of claim 14, further comprising:

determining that a reporting delay initiated from the CSI-RS trigger exceeds the second time slot by at least a threshold number of time slots; and

transmitting the CSI report in a third slot corresponding to the timing delay indicated in the CSI report trigger.

18. The method of claim 13, further comprising:

determining that the carrier is one component carrier of a plurality of configured component carriers;

performing measurements of CSI-RSs received in the slot on at least a second component carrier of the plurality of component carriers; and

transmitting a CSI report including the measurements for the CSI-RS received in the slot on the at least the second component carrier.

19. A method for wireless communication at a base station, comprising:

transmitting a channel state information reference signal (CSI-RS) trigger and an uplink grant;

identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant;

determining a communication configuration for the CSI-RS and the uplink data based at least in part on the pending conflict;

identifying a CSI reporting trigger; and

determining a CSI reporting configuration based at least in part on the communication configuration and the CSI reporting trigger.

20. The method of claim 19, wherein determining the communication configuration for the CSI-RS and the uplink data further comprises:

transmitting the CSI-RS in the slot; and

transmitting a signal indicating that the uplink grant is not transmitted and requesting retransmission of the uplink data.

21. The method of claim 19, wherein determining the communication configuration for the CSI-RS and the uplink data further comprises:

determining that CSI-RS for the slot has been discontinued by a base station; and

transmitting the uplink data in the time slot.

22. The method of claim 19, further comprising:

determining a backoff period comprising one or more time slots; and

sending an indication of the backoff period to the UE.

23. The method of claim 22, further comprising:

transmitting a set of backoff periods in a first downlink control signal; and

wherein sending the indication further comprises: transmitting a second downlink control signal comprising the indication of the backoff period, wherein the indication corresponds to one of the set of backoff periods.

24. The method of claim 23, wherein at least one of the first downlink control signal and the second downlink control signal comprises Downlink Control Information (DCI), a Media Access Control (MAC) Control Element (CE), or a Radio Resource Control (RRC) message.

25. The method of claim 19, further comprising:

determining the CSI-RS resource amount;

wherein determining the communication configuration comprises:

determining a number of downlink symbols and a number of uplink symbols within the slot for transmitting the CSI-RS and receiving the uplink data in the slot;

performing rate matching of the uplink data based at least in part on the number of uplink symbols; and

transmitting the CSI-RS using the downlink symbol in the slot and receiving the uplink data using the uplink symbol in the slot.

26. The method of claim 19, further comprising:

identifying a downlink control channel corresponding to a first portion of the time slot; and

multiplexing the CSI-RS into the first portion of the slot using one of Frequency Division Multiplexing (FDM), Code Division Multiplexing (CDM), or Time Division Multiplexing (TDM).

27. The method of claim 19, further comprising:

determining that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period; and

transmitting the CSI-RS in a second slot corresponding to the first backoff period from the slot.

28. The method of claim 19, further comprising:

determining that a reporting delay initiated from the CSI-RS trigger does not exceed the second time slot by at least a threshold number of time slots;

determining a second backoff period comprising the first backoff period or a reporting delay;

configuring the UE with the second backoff period via at least one downlink control signal, wherein the at least one downlink control signal comprises Downlink Control Information (DCI), a Medium Access Control (MAC) Control Element (CE), a Radio Resource Control (RRC) message, or a combination thereof; and

receiving a CSI report in a third time slot corresponding to the second backoff period from the time slot in which a CSI report is triggered.

29. An apparatus for wireless communication at a User Equipment (UE), comprising:

means for receiving a channel state information reference signal (CSI-RS) trigger and an uplink grant;

means for identifying, for a slot of a carrier, a pending collision between a CSI-RS corresponding to a CSI-RS trigger and uplink data corresponding to the uplink grant;

means for determining a communication configuration for the CSI-RS and the uplink data based at least in part on the pending conflict;

means for identifying a CSI reporting trigger; and

means for determining a CSI reporting configuration based at least in part on the communication configuration and the CSI reporting trigger.

30. An apparatus for wireless communication at a base station, comprising:

means for transmitting a channel state information reference signal (CSI-RS) trigger and an uplink grant;

means for identifying, for a slot of a carrier, a pending collision between a CSI-RS corresponding to a CSI-RS trigger and uplink data corresponding to the uplink grant;

means for determining a communication configuration for the CSI-RS and the uplink data based at least in part on the pending conflict;

means for identifying a CSI reporting trigger; and

means for determining a CSI reporting configuration based at least in part on the communication configuration and the CSI reporting trigger.

Technical Field

The following relates generally to wireless communications, and more particularly to a collision handling mechanism for a dynamic Time Division Duplex (TDD) system.

Background

Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be able to support communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Orthogonal Frequency Division Multiple Access (OFDMA) systems (e.g., Long Term Evolution (LTE) systems or New Radio (NR) systems). A wireless multiple-access communication system may include multiple base stations or access network nodes, each supporting communication for multiple communication devices (which may otherwise be referred to as User Equipment (UE)) simultaneously.

In some examples, a base station may communicate with a UE in a wireless communication system. The base station may send a CSI-RS trigger to the UE, which may indicate to the UE that the base station is to send CSI-RS. In addition, the base station may transmit an uplink grant, which may indicate resources for the UE to transmit uplink data. The downlink CSI-RS transmission and the uplink data transmission may be associated with independent time delays between the trigger or grant and the transmission. In some examples, the time delays corresponding to CSI-RS transmissions and uplink data transmissions may be configured such that the CSI-RS and uplink data transmissions collide within a single slot.

Disclosure of Invention

The described technology relates to improved methods, systems, devices or apparatus that support collision handling mechanisms for dynamic Time Division Duplex (TDD) systems. In general, described techniques provide for receiving an uplink grant and a channel state information reference signal (CSI-RS) trigger at a User Equipment (UE). Based on the received downlink signal, the UE and the base station may identify, for a time slot of a carrier (e.g., a TDD carrier), a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant. The UE and the base station may determine communication configurations for the CSI-RS and the uplink data such that no collision occurs. The determined communication configuration for the CSI-RS may include: delaying one of the colliding signals, transmitting only one of the colliding signals and suppressing the other signal, or reconfiguring the time slot so that both signals can be successfully transmitted. In addition, the UE and the base station may determine a CSI reporting configuration based on the determined communication configuration.

A method of wireless communication at a UE is described. The method may include: receiving a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

An apparatus for wireless communication at a UE is described. The apparatus may include: a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: receiving a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

Another apparatus for wireless communication at a UE is described. The apparatus may include means for: receiving a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to: receiving a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the communication configuration for the CSI-RS and the uplink data may further include operations, features, means, or instructions for: refraining from transmitting the uplink data in the time slot; receiving the CSI-RS in the slot; and receiving a signal indicating that the uplink grant is not transmitted and requesting retransmission of the uplink data.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the communication configuration for the CSI-RS and the uplink data may further include operations, features, means, or instructions for: determining that the CSI-RS for the slot may have been aborted by a base station; and transmitting the uplink data in the time slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: refraining from performing measurements corresponding to the suppressed CSI-RS for the slot on the carrier.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: refraining from transmitting a CSI report associated with the refrained CSI-RS.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: transmitting a CSI report associated with the CSI reporting trigger for the carrier based on measurements of CSI-RSs performed prior to the time slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that the carrier may be one component carrier of a set of configured component carriers; identifying a CSI-RS received in the timeslot on at least one second component carrier of the set of configured component carriers; performing measurements of the identified CSI-RS received in the slot on the at least one second component carrier; and transmitting a CSI report for the second component carrier based on the measurements for the CSI-RS received in the slot on the at least one second component carrier.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining a backoff period comprising one or more time slots; receiving the CSI-RS in the slot; and transmitting the uplink data in a second slot determined by applying the backoff period from the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining the backoff period further comprises and the method further comprises.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining a backoff period comprising one or more time slots; transmitting the uplink data in the time slot; and receiving the CSI-RS in a second slot determined by applying the backoff period from the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining an amount of CSI-RS resources, wherein determining the communication configuration comprises: performing rate matching on the uplink data based on the number of uplink symbols; and receiving the CSI-RS using the downlink symbol in the slot and transmitting the uplink data using the uplink symbol in the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: identifying a downlink control channel received via a first portion of the timeslot; and receiving the CSI-RS multiplexed into the first portion of the timeslot using one of Frequency Division Multiplexing (FDM), Code Division Multiplexing (CDM), or Time Division Multiplexing (TDM).

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period; and performing a measurement of the CSI-RS received in a second slot corresponding to the first backoff period from the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that a reporting delay initiated from the CSI-RS trigger does not exceed the second time slot by at least a threshold number of time slots; determining a second backoff period comprising the first backoff period or a reporting delay; and transmitting a CSI report in a third slot corresponding to the second backoff period from the slot in which the CSI report is triggered.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the second backoff period may further comprise operations, features, units, or instructions for: a second set of backoff periods is received in the first downlink control signal, and the method further comprises.

In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, at least one of the first downlink control signal and the second downlink control signal comprises Downlink Control Information (DCI), a Media Access Control (MAC) Control Element (CE), or a Radio Resource Control (RRC) message.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that a reporting delay initiated from the CSI-RS trigger exceeds the second time slot by at least a threshold number of time slots; and transmitting the CSI report in a third slot corresponding to the timing delay indicated in the CSI report trigger.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that the carrier may be one component carrier of a set of configured component carriers; performing measurements of CSI-RSs received in the slot on at least a second component carrier of the set of component carriers; and transmitting a CSI report comprising the measurements for the CSI-RS received in the slot on the at least the second component carrier.

A method of wireless communication at a base station is described. The method may include: transmitting a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

An apparatus for wireless communication at a base station is described. The apparatus may include: a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: transmitting a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

Another apparatus for wireless communication at a base station is described. The apparatus may include means for: transmitting a channel state information reference signal (CSI-RS) trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

A non-transitory computer-readable medium storing code for wireless communication at a base station is described. The code may include instructions executable by a processor to: transmitting a CSI-RS trigger and an uplink grant; identifying, for a time slot of a carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant; determining a communication configuration for the CSI-RS and the uplink data based on the pending conflict; identifying a CSI reporting trigger; and determining a CSI reporting configuration based on the communication configuration and the CSI reporting trigger.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the communication configuration for the CSI-RS and the uplink data may further include operations, features, means, or instructions for: transmitting the CSI-RS in the slot; and transmitting a signal indicating that the uplink grant is not transmitted and requesting retransmission of the uplink data.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, determining the communication configuration for the CSI-RS and the uplink data may further include operations, features, means, or instructions for: determining that the CSI-RS for the slot may have been aborted by a base station; and transmitting the uplink data in the time slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining a backoff period comprising one or more time slots; and sending an indication of the backoff period to the UE.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: transmitting a set of backoff periods in a first downlink control signal, and wherein transmitting the indication further comprises: transmitting a second downlink control signal comprising the indication of the backoff period, wherein the indication corresponds to one of the set of backoff periods.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, at least one of the first downlink control signal and the second downlink control signal comprises a DCI, MAC-CE, or RRC message.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining an amount of CSI-RS resources, wherein determining the communication configuration comprises: performing rate matching on the uplink data based on the number of uplink symbols; and transmitting the CSI-RS using the downlink symbol in the slot and receiving the uplink data using the uplink symbol in the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: identifying a downlink control channel corresponding to a first portion of the time slot; and multiplexing the CSI-RS into the first portion of the slot using one of FDM, CDM, or TDM.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period; and transmitting the CSI-RS in a second slot corresponding to the first backoff period from the slot.

Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions to: determining that a reporting delay initiated from the CSI-RS trigger does not exceed the second time slot by at least a threshold number of time slots; determining a second backoff period comprising the first backoff period or a reporting delay; configuring the UE with the second backoff period via at least one downlink control signal, wherein the at least one downlink control signal comprises DCI, MAC CE, RRC message, or a combination thereof; and receiving a CSI report in a third slot corresponding to the second backoff period from the slot in which the CSI report is triggered.

Drawings

Fig. 1 illustrates an example of a system for wireless communication that supports a collision handling mechanism for a dynamic Time Division Duplex (TDD) system, in accordance with aspects of the present disclosure.

Fig. 2 illustrates an example of a wireless communication system that supports a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 3 illustrates an example of a wireless communication timing configuration supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 4 illustrates an example of a wireless communication timing configuration supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 5 illustrates an example of a wireless communication timing configuration supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 6 illustrates an example of a wireless communication timing configuration supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 7 illustrates an example of a process flow to support a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 8 illustrates an example of a process flow to support a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 9 to 11 show block diagrams of devices supporting a collision handling mechanism for a dynamic TDD system according to aspects of the present disclosure.

Fig. 12 shows a block diagram of a system including a UE supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 13 illustrates a block diagram of a system including a base station supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Fig. 14 illustrates a method for a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure.

Detailed Description

In some examples of a wireless communication system, a base station may communicate with a User Equipment (UE) in the wireless communication system. The base station may send a channel state information reference signal (CSI-RS) trigger to the UE, which may indicate to the UE that the base station is to send CSI-RS after a timing delay. In addition, the base station may transmit an uplink grant, which may indicate resources for the UE to transmit uplink data. The uplink data transmission may be associated with a time delay between the grant and the uplink data transmission. In some examples, the time delays corresponding to CSI-RS transmissions and uplink data transmissions may be configured such that the CSI-RS and uplink data transmissions collide within a single slot.

In some examples, based on the CSI-RS trigger and the uplink grant, the UE and the base station may identify, for a time slot of a Time Division Duplex (TDD) carrier, a pending collision between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant. The UE and the base station may determine communication configurations for the CSI-RS and the uplink data such that no collision occurs. The determined communication configuration for the CSI-RS may include: delaying one of the colliding signals, transmitting only one of the colliding signals and suppressing the other signal, or reconfiguring the time slot so that both signals can be successfully transmitted. In addition, the UE and the base station may determine a CSI reporting configuration based on the determined communication configuration.

Aspects of the present disclosure are first described in the context of a wireless communication system. Aspects of the present disclosure are further illustrated by and described with reference to wireless communication timing configurations and flow diagrams. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flow charts directed to a collision handling mechanism for a dynamic TDD system.

Fig. 1 illustrates an example of a wireless communication system 100 in accordance with various aspects of the present disclosure. The wireless communication system 100 includes base stations 105, UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE), LTE-advanced (LTE-a) network, or a New Radio (NR) network. In some cases, the wireless communication system 100 may support enhanced broadband communications, ultra-reliable (i.e., mission-critical) communications, low latency communications, and communications with low cost and low complexity devices. The wireless communication system 100 may support a collision handling mechanism for a dynamic TDD system according to aspects of the present disclosure. For example, the base station 105 may send an uplink grant and a CSI-RS trigger. The UE115 may receive a downlink signal conveying an uplink grant and a CSI-RS trigger and identify a pending collision on a time slot of a carrier (e.g., a TDD carrier) between a CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant. The UE115 and the base station 105 may determine a communication configuration for the CSI-RS and the uplink data based on the pending collision. The communication configuration may include: one of the colliding signals is suppressed and the other signal is transmitted. In some examples, the communication configuration may include: one of the colliding signals is delayed. In yet another example, the communication configuration may include: the time slots are reconfigured so that both of the colliding signals can be successfully transmitted.

In addition, the base station 105 and the UE115 may determine a CSI reporting configuration based on the communication configuration. For example, the CSI report may be delayed if one of the colliding signals is delayed, or the UE may refrain from sending the CSI report if the CSI-RS is suppressed. In some examples, the CSI report may be based on a previous aperiodic CSI-RS, or based on previous or subsequent instances of a periodic CSI-RS or a semi-persistent CSI-RS.

The base station 105 may communicate wirelessly with the UE115 via one or more base station antennas. Each base station 105 may provide communication coverage for a respective geographic coverage area 110. The communication links 125 shown in the wireless communication system 100 may include: uplink transmissions from the UE115 to the base station 105, or downlink transmissions from the base station 105 to the UE 115. Control information and data may be multiplexed on an uplink channel or a downlink according to various techniques. For example, control information and data may be multiplexed on the downlink channel using Time Division Multiplexing (TDM) techniques, Frequency Division Multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. In some examples, control information transmitted during a Transmission Time Interval (TTI) of a downlink channel may be distributed in a cascaded manner between different control regions (e.g., between a common control region and one or more UE-specific control regions).

The UEs 115 may be dispersed throughout the wireless communication system 100, and each UE115 may be stationary or mobile. UE115 may also be referred to as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless communication device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. The UE115 may also be a cellular phone, a Personal Digital Assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a personal electronic device, a handheld device, a personal computer, a Wireless Local Loop (WLL) station, an internet of things (IoT) device, an internet of everything (IoE) device, a Machine Type Communication (MTC) device, an appliance, an automobile, and so forth.

In some cases, the UE115 may also be capable of communicating directly with other UEs (e.g., using peer-to-peer (P2P) or device-to-device (D2D) protocols). One or more UEs 115 in the group of UEs 115 communicating with D2D may be within the geographic coverage area 110 of the cell. Other UEs 115 in such a group may be outside the geographic coverage area 110 of the cell or otherwise unable to receive transmissions from the base station 105. In some cases, multiple groups of UEs 115 communicating via D2D communication may utilize a one-to-many (1: M) system, where each UE115 transmits to every other UE115 in the group. In some cases, the base station 105 facilitates scheduling of resources for D2D communication. In other cases, the D2D communication is performed independently of the base station 105.

Some UEs 115, such as MTC or IoT devices, may be low cost or low complexity devices and may provide automated communication between machines, i.e., machine-to-machine (M2M) communication. M2M or MTC may refer to data communication techniques that allow devices to communicate with each other or a base station without human intervention. For example, M2M or MTC may refer to communications from a device that integrates sensors or meters to measure or capture information and relay the information to a central server or application that may utilize the information or present the information to a human interacting with the program or application. Some UEs 115 may be designed to collect information or implement automated behavior of machines. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, device monitoring, healthcare monitoring, wildlife monitoring, climate and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based service billing.

In some cases, MTC devices may operate using half-duplex (one-way) communications at a reduced peak rate. The MTC device may be further configured to: when not engaged in active communication, a power-saving "deep sleep" mode is entered. In some cases, MTC or IoT devices may be designed to support mission critical functions, and wireless communication systems may be configured to provide ultra-reliable communication for these functions.

The base stations 105 may communicate with the core network 130 and with each other. For example, the base station 105 may interface with the core network 130 over a backhaul link 132 (e.g., S1, etc.). The base stations 105 may communicate with each other directly or indirectly (e.g., through the core network 130) over a backhaul link 134 (e.g., X2, etc.). The base station 105 may perform radio configuration and scheduling for communications with the UE115 or may operate under the control of a base station controller (not shown). In some examples, the base station 105 may be a macro cell, a small cell, a hot spot, and so on. The base station 105 may also be referred to as an evolved node b (enb) 105.

The base station 105 may be connected to the core network 130 through an S1 interface. The core network may be an Evolved Packet Core (EPC) that may include at least one Mobility Management Entity (MME), at least one serving gateway (S-GW), and at least one Packet Data Network (PDN) gateway (P-GW). The MME may be a control node that handles signaling between the UE115 and the EPC. All user Internet Protocol (IP) packets may be transported through the S-GW, which may itself be connected to the P-GW. The P-GW may provide IP address assignment as well as other functions. The P-GW may be connected to network operator IP services. Operator IP services may include the internet, intranets, IP Multimedia Subsystem (IMS), and Packet Switched (PS) streaming services.

The core network 130 may provide user authentication, access admission, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. At least some of the network devices may be examples of intelligent radio heads or transmission/reception points (TRPs). In some configurations, the various functions of each access network entity or base station 105 may be distributed across various network devices (e.g., radio heads and access network controllers) or consolidated into a single network device (e.g., base station 105).

Although the wireless communication system 100 may operate in a very high frequency (UHF) frequency region using a frequency band from 700MHz to 2600MHz (2.6GHz), some networks, such as Wireless Local Area Networks (WLANs), may use frequencies as high as 4 GHz. This region may also be referred to as the decimeter band because the wavelength range is from approximately one decimeter to one meter in length. UHF waves may propagate primarily through the line of sight and may be blocked by building and environmental features. However, these waves may be sufficient to penetrate walls to provide service to UEs 115 located indoors. UHF-wave transmission is characterized by smaller antennas and shorter distances (e.g., less than 100km) than transmission of smaller frequencies (and longer waves) using the High Frequency (HF) or Very High Frequency (VHF) portion of the spectrum. In some cases, wireless communication system 100 may also utilize the Extremely High Frequency (EHF) portion of the spectrum (e.g., from 30GHz to 300 GHz). This region may also be referred to as the millimeter-band because the wavelength ranges from approximately one millimeter to one centimeter in length. Accordingly, the EHF antennas may be even smaller and more closely spaced compared to UHF antennas. In some cases, this may facilitate the use of an antenna array (e.g., for directional beamforming) within the UE 115. However, EHF transmissions may suffer from even greater atmospheric attenuation and shorter distances than UHF transmissions.

Thus, the wireless communication system 100 may support millimeter wave (mmW) communication between the UE115 and the base station 105. Devices operating in mmW or EHF bands may have multiple antennas to allow beamforming. That is, the base station 105 may use multiple antennas or antenna arrays for beamforming operations for directional communication with the UEs 115. Beamforming (which may also be referred to as spatial filtering or directional transmission) is a signal processing technique as follows: the techniques may be used at a transmitter (e.g., base station 105) to beamform and/or steer an overall antenna in the direction of a target receiver (e.g., UE 115). This can be achieved by: elements in an antenna array are combined in such a way that signals transmitted at a particular angle undergo constructive interference, while other signals undergo destructive interference.

A multiple-input multiple-output (MIMO) wireless system uses a transmission scheme between a transmitter (e.g., base station 105) and a receiver (e.g., UE115), where both the transmitter and the receiver are equipped with multiple antennas. Portions of the wireless communication system 100 may use beamforming. For example, the base station 105 may have an antenna array with multiple rows and columns of antenna ports that the base station 105 may use to beamform in its communications with the UEs 115. The signal may be transmitted multiple times in different directions (e.g., each transmission may be beamformed in a different manner). A mmW receiver (e.g., UE115) may attempt multiple beams (e.g., antenna sub-arrays) when receiving synchronization signals.

In some cases, the antennas of a base station 105 or UE115 may be located within one or more antenna arrays, which may support beamforming or MIMO operation. One or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some cases, the antennas or antenna arrays associated with the base station 105 may be located at different geographic locations. The base station 105 may use multiple antennas or antenna arrays for beamforming operations for directional communication with the UEs 115.

In some cases, the wireless communication system 100 may be a packet-based network operating according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer may be IP-based. In some cases, the Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate on logical channels. A Medium Access Control (MAC) layer may perform priority processing and multiplexing of logical channels to transport channels. The MAC layer may also use hybrid arq (harq) to provide retransmissions at the MAC layer to improve link efficiency. In the control plane, a Radio Resource Control (RRC) protocol layer may provide for establishment, configuration, and maintenance of RRC connections (supporting radio bearers for user plane data) between the UE115 and the network device 105-c, network device 105-b, or core network 130. At the Physical (PHY) layer, transport channels may be mapped to physical channels.

A basic unit of time (which may be T) may be utilized_sA sampling period of 1/30,720,000 seconds) to represent the time interval in LTE or NR. May be based on a 10ms length (T)_f＝307200T_s) The radio frames of (a) organize the time resources, which radio frames may be identified by System Frame Numbers (SFNs) ranging from 0 to 1023. Each frame may include ten 1ms subframes numbered from 0 to 9. The sub-frame may be further divided into two 0.5ms slots, each slot containing 6 or 7 modulation symbol periods (depending on the length of the cyclic prefix added in front of each symbol). Each symbol contains 2048 sample periods, excluding the cyclic prefix. At one endIn some cases, a subframe may be a minimum scheduling unit, also referred to as a TTI. In other cases, the TTI or slot may be shorter than a subframe or may be dynamically selected (e.g., in a short TTI burst or in a selected component carrier using a short TTI). For example, a slot may correspond to a TTI and may be a configurable number of symbol periods in length.

The resource element may include one symbol period and one subcarrier (e.g., 15KHz frequency range). A resource block may contain 12 consecutive subcarriers in the frequency domain and 7 consecutive OFDM symbols in the time domain (1 slot), or 84 resource elements for a normal cyclic prefix in each OFDM symbol. The number of bits carried by each resource element may depend on the modulation scheme (the configuration of symbols that may be selected during each symbol period). Thus, the more resource blocks the UE receives and the higher the modulation scheme, the higher the data rate may be.

The wireless communication system 100 may support operation over multiple cells or carriers (a feature that may be referred to as Carrier Aggregation (CA) or multi-carrier operation). The carriers may also be referred to as Component Carriers (CCs), layers, channels, and the like. The terms "carrier," "component carrier," "cell," and "channel" may be used interchangeably herein. A UE115 may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation. Carrier aggregation may be used with both frequency division multiplexed (FDD) and TDD component carriers.

In some cases, the wireless communication system 100 may utilize an enhanced component carrier (eCC). An eCC may be characterized by one or more features including: wider bandwidth, shorter symbol duration, shorter TTI, and modified control channel configuration. In some cases, an eCC may be associated with a carrier aggregation configuration or a dual connectivity configuration (e.g., when multiple serving cells have suboptimal or non-ideal backhaul links). An eCC may also be configured for use in unlicensed spectrum or shared spectrum (where more than one operator is allowed to use the spectrum). An eCC characterized by a wide bandwidth may include one or more segments that may be used by UEs 115 that cannot monitor the entire bandwidth or prefer to use a limited bandwidth (e.g., to save power).

In some cases, an eCC may utilize a different symbol duration than other CCs, which may include using a reduced symbol duration compared to the symbol durations of the other CCs. Shorter symbol durations may be associated with increased subcarrier spacing. A device utilizing an eCC, such as a UE115 or a base station 105, may transmit a wideband signal (e.g., 20, 40, 60, 80MHz, etc.) with a reduced symbol duration (e.g., 16.67 microseconds). A TTI in an eCC may include one or more symbols. In some cases, the TTI duration (i.e., the number of symbols in a TTI) may be variable.

A shared radio frequency spectrum band may be utilized in an NR shared spectrum system. For example, NR shared spectrum may utilize any combination of licensed, shared, and unlicensed spectrum, among others. Flexibility in eCC symbol duration and subcarrier spacing may allow eCC to be used across multiple frequency spectrums. In some examples, NR sharing spectrum may improve spectrum utilization and spectrum efficiency, particularly through dynamic vertical (e.g., across frequency) and horizontal (e.g., across time) sharing of resources.

In some cases, the wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 may employ LTE licensed assisted access (LTE-LAA) or LTE unlicensed (LTE U) radio access technology or NR technology in unlicensed bands, such as the 5Ghz industrial, scientific, and medical (ISM) band. When operating in the unlicensed radio frequency spectrum band, wireless devices, such as base stations 105 and UEs 115, may employ a Listen Before Talk (LBT) procedure to ensure that the channel is idle before transmitting data. In some cases, operation in the unlicensed band may be based on CA configurations in conjunction with CCs operating in the licensed band. Operations in the unlicensed spectrum may include downlink transmissions, uplink transmissions, or both. Duplexing in unlicensed spectrum may be based on Frequency Division Duplexing (FDD), TDD, or a combination of both.

In some examples, the base station 105 may collect channel condition information from the UEs 115 in order to efficiently configure and schedule channels. This information may be sent from the UE115 in the form of a channel state report. The channel state report may include an RI requesting the number of layers to be used for Downlink (DL) transmission (e.g., based on the antenna ports of the UE115), a PMI indicating a preference for which precoder matrix should be used (based on the number of layers), and Channel Quality Information (CQI) indicating the highest Modulation Coding Scheme (MCS) that may be used. The UE115 may calculate the CQI after receiving predetermined pilot symbols, such as cell-specific reference signals (CRS) or CSI-RS. The RI and PMI may not be included if the UE115 does not support spatial multiplexing (or does not support spatial mode). The type of information included in the report determines the report type. The channel state report may be periodic or aperiodic. That is, the base station 105 may configure the UE115 to transmit periodic reports at regular intervals, and may also request additional reports as needed. Aperiodic reports can include: a wideband report indicating channel quality across the entire cell bandwidth; a report selected by the UE indicating a subset of best subbands; or a configured report in which the reported sub-band is selected by the base station 105.

Fig. 2 illustrates an example of a wireless communication system 200 that supports a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the disclosure. In some examples, the wireless communication system 200 may implement aspects of the wireless communication system 100. The wireless communication system 200 may include a base station 105-a and a UE115-a, which may be examples of corresponding devices described with reference to fig. 1.

In some examples, a base station 105-a may communicate with one or more UEs 115 within a geographic coverage area 205. For example, the base station 105-a may communicate with the UE115-a via a bi-directional communication link 210. The base station 105-a may send a CSI-RS trigger. The CSI-RS trigger may be an aperiodic CSI-RS trigger, which may be associated with a time delay after which the base station 105-a may transmit the CSI-RS 215. In some examples, the CSI-RS trigger may correspond to a semi-persistent CSI-RS or a periodic CSI-RS, in which case CSI-RS215 may occur repeatedly at a particular periodicity. In addition, the base station 105-a may send an uplink grant to the UE 115-a. The uplink grant may be associated with a time delay after which the UE115-a may transmit the uplink data 220. In some instances, the trigger event and timing delay may cause transmissions of CSI-RS215 and transmissions of uplink data 220 to be scheduled to collide within a single time slot.

In such an example, the base station 105-a and the UE115-a may determine a communication configuration to resolve the conflict. In some examples, one of CSI-RS215 and uplink data 220 may be overwritten (overriden). For example, the UE115-a may refrain from transmitting the uplink data 220, thereby allowing the base station 105-a to transmit the CSI-RS215 without collision. Alternatively, the base station 105-a may refrain from transmitting the CSI-RS215, thereby allowing the UE115-a to transmit the uplink data 220 without collision. In some examples, a backoff period may be applied to one of CSI-RS215 or uplink data 220. For example, the base station 105-a may transmit the CSI-RS215 within the scheduled time slot. In such an example, the UE115-a may apply a timing offset to the uplink data 220 such that the uplink data 220 is delayed by the timing offset after the scheduled time slot. Alternatively, the UE115-a may transmit uplink data 220 at its scheduled time slot. In such an example, the base station 105-a may apply a timing offset to the CSI-RS215 such that the CSI-RS215 is delayed by the timing offset after the scheduled time slot.

In some examples, the UE115-a and the base station 105-a may reconfigure the slots in which collisions are identified so that both the CSI-RS215 and the uplink data 220 can be successfully transmitted without collisions. The UE115-a may determine a number of symbols configured for uplink transmission and may perform rate matching based on a total amount of aperiodic, periodic, or semi-persistent resources. In some examples, the UE115-a and the base station 105-a may multiplex the CSI-RS215 into the PDCCH region of the slot in which the uplink data 220 is scheduled.

In determining one or more of the above-mentioned methods for detected collisions between CSI-RS215 and uplink data 220, the UE115-a may determine a CSI-RS reporting configuration. For example, if the base station 105-a suppresses the CSI-RS215, the UE115-a may not send a CSI-RS report. The base station 105-a may determine that no CSI report is to be sent and will not expect to receive any CSI report from the UE 115-a. In some cases, the UE115-a may operate in a carrier aggregation mode. In such an example, the UE115-a may determine that the CSI-RS215 has been suppressed on a first component carrier, but may receive the CSI-RS215 on one or more additional component carriers. The UE115-a may perform measurements on one or more additional component carriers and may send CSI reports. The CSI report may have a smaller payload because the CSI report does not include CSI measurements corresponding to the first component carrier on which measurements are not performed.

In some examples, the UE115-a may determine that the base station 105-a has suppressed the CSI-RS 215. In such an example, the UE115-a may refrain from taking measurements corresponding to the CSI-RS 215. Alternatively, the UE115-a may send a CSI report containing measurements corresponding to the previous CSI-RS 215. In some examples, the UE115-a may operate in a carrier aggregation mode. In such an example, the UE115-a may perform measurements on each of the latest CSI-RS signals (e.g., previous CSI-RS) relative to the slot in which the CSI report is to be sent. In some examples, CSI-RS215 may be a periodic CSI-RS or a semi-persistent CSI-RS. In such a case, CSI-RS215 may be one of a plurality of CSI-RS transmissions (e.g., one of a plurality of instances of a CSI-RS scheduled using a single CSI-RS trigger or configuration message). In some such instances, the UE115-a may receive one or more CSI-RS instances, but may not receive all CSI-RS instances. In such a case, the UE115-a may perform CSI measurements on the received CSI-RS instance and refrain from performing measurements on the slots in which the CSI-RS instance is suppressed. In the case where the UE115-a operates in carrier aggregation mode, the UE115-a may send a corresponding CSI report based on measurements for previously received CSI-RS instances.

In some examples, the UE115-a may determine that the CSI-RS215 has been transmitted after a backoff period (rather than at a regularly scheduled time slot). In such a case, the UE115-a may determine the second backoff period. For example, the second backoff period may be determined by adding some further offset to the first backoff period. The CSI-RS may be transmitted after a first backoff period from the slot, and the CSI report may be transmitted after a second backoff period from the transmitted CSI-RS. The second backoff period may be the same as or different from the first backoff period.

Fig. 3 illustrates an example of a wireless communication timing configuration 300 that supports a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the disclosure. In some examples, the wireless communication timing configuration 300 may implement aspects of the wireless communication system 100 and the wireless communication system 200. The wireless communication timing configuration 300 may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1 and 2).

The base station 105-a may transmit the CSI-RS trigger 305 at time t1 (e.g., in slot n). In some examples, the CSI-RS trigger 305 may configure an aperiodic CSI-RS. The CSI-RS trigger 305 may correspond to the CSI-RS 310. The UE115-a may receive the CSI-RS trigger 305 in slot n, and the aperiodic CSI-RS310 may be associated with a timing delay X320. The timing delay X320 may be equal to a number of slots (e.g., three slots) following the slot in which the CSI-RS trigger 305 is received (e.g., slot n). Alternatively, the timing delay X320 may be equal to some amount of time (e.g., a number of symbol periods or microseconds, etc.) independent of the number of slots. If the UE115-a receives the CSI-RS trigger 305 in slot n and the timing delay X315 is equal to three (3) slots, the UE115-a may determine that the base station 105-a may transmit the CSI-RS310 at slot n + 3. The timing delay X320 may be configured by a downlink control signal, e.g., CSI-RS trigger 305 or a higher layer signal, such as an RRC signal or MAC CE.

In the example of fig. 3, the base station 105-a may transmit the uplink grant 315 during time slot n + 1. The uplink grant 315 may indicate resources on which the UE115-a may transmit uplink data 325. The UE115-a may transmit uplink data 325 corresponding to the uplink grant 315 in a time slot after the timing delay K2330. Timing delay K2330 may be equal to a number of slots (e.g., two slots) following the slot in which uplink grant 315 is received (e.g., slot n + 1). In some cases, timing delay K2330 may be equal to an amount of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). Thus, if UE115-a receives uplink grant 315 in time slot n +1, and timing delay K2330 is equal to one time slot, UE115-a may transmit uplink data 325 at time slot n + 3. The timing delay K2330 may be configured by a downlink control signal, e.g., an uplink grant 320 or a higher layer signal, such as an RRC signal or MAC CE.

In some examples, the UE115-a may perform measurements corresponding to the CSI-RS310 and may send CSI reports 340 associated with the measurements. The UE115-a may determine a timing delay Y345 between receiving the CSI report trigger 350 and sending the CSI report 340. The timing delay Y345 may be equal to a number of slots (e.g., two slots) and may be configured by a downlink control signal (e.g., CSI-RS trigger 305 or a higher layer signal such as an RRC signal or MAC CE). In some cases, timing delay Y345 may be equal to an amount of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). In some examples, the UE115-a may receive a separate downlink control signal, which may include a CSI reporting trigger that initiates the CSI report 340. Thus, if the UE115-a receives the CSI report trigger 350 in slot n +3 and Y345 equals two slots, the UE115-a may send the CSI report 340 in slot n + 5.

As described above, the uplink data 325 and the CSI-RS310 may collide in a single slot (e.g., slot n + 3). The base station 105-a and the UE115-a may determine that a conflict will occur and determine a communication configuration to resolve the conflict. For example, the UE115-a may refrain from transmitting the uplink data 325, allowing the UE115-a to receive the CSI-RS310 without collision. The base station 105-a may be aware of the suppression of the uplink data 325 and may transmit the CSI-RS 310. In addition, the base station 105-a may determine that it will not receive or decode any uplink data corresponding to the uplink grant 320 during time slot n +3 based on the suppression of the uplink data 325. The base station 105-a may send a signal (e.g., a Negative Acknowledgement (NACK) signal) to the UE115-a indicating that the uplink data was not successfully transmitted to request retransmission of the uplink data 325. In some examples, the base station 105-a may refrain from transmitting the CSI-RS310, allowing the UE115-a to send uplink data 325 during slot n +3 without collision. In such an example, the UE115-a may determine suppression of the CSI-RS310 and may not desire to receive the CSI-RS 310.

In some examples, the UE115-a and the base station 105-a may dynamically determine whether to suppress the CSI-RS310 or the uplink data 325. In some examples, the UE115-a and the base station 105-a may select which transmission to suppress based on which transmission is configured later. For example, if the CSI-RS trigger 305 is received first (e.g., during slot n) at the UE115-a and the uplink grant 320 is received later (e.g., during slot n +1) at the UE115-a, the base station 105-a may suppress the CSI-RS 310. Alternatively, the UE115-a may suppress the uplink data 325 if the CSI-RS trigger 305 is received later than the uplink grant 320. In some examples, the rules may be predefined such that both UE115-a and base station 105-a are aware of the rules. Alternatively, base station 105-a may determine which transmission to suppress and may indicate to UE115-a which transmission to suppress. For example, the base station 105-a may send an indicator (e.g., in the CSI-RS trigger 305, the uplink grant 320, or a separate Downlink Control Information (DCI) transmission) that includes one or two bits indicating which transmission is to be suppressed.

In some examples, transmission backoff may be applied to one of CSI-RS310 or uplink data 325. That is, one of the transmissions may be rolled back and the other transmission allowed to be sent without collision. In some examples, the UE115-a may determine and apply the backoff period 335 to the uplink data 325. The backoff period 335 may be equal to a number of slots (e.g., at least one slot), or a set of amounts of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). Applying the backoff period 335 to the uplink data 325 may allow the base station 105-a to transmit the CSI-RS310 during time slot n +3 without colliding with the uplink data 325, and may allow the UE115-a to transmit the uplink data 325 at a later time (e.g., after the backoff period 335 during time slot n + 4). Alternatively, the base station 105-a may determine the backoff period 335 and apply it to the CSI-RS 310. In such an example, the UE115-a may transmit the uplink data 325 during slot n +3, and the base station 105-b may transmit the CSI-RS310 after the backoff period 335 during a later slot (e.g., slot n + 4).

In some examples, the UE115-a and the base station 105-a may dynamically determine whether to apply the backoff period 335 to the CSI-RS310 or the uplink data 325. In some examples, the UE115-a and the base station 105-a may select to which transmission to apply the backoff period 335 based on which transmission is configured later. For example, if the CSI-RS trigger 305 is received first (e.g., during slot n) at the UE115-a and the uplink grant 320 is received later (e.g., during slot n +1) at the UE115-a, the base station 105-a may apply a backoff period 335 to the CSI-RS 310. Alternatively, if the CSI-RS trigger 305 is received later than the uplink grant 320, the UE115-a may apply a backoff period 335 to the uplink data 325. In some examples, the rules may be predefined such that both UE115-a and base station 105-a are aware of the rules. Alternatively, base station 105-a may determine to apply a backoff period 335 to one of the transmissions and may indicate the determination to UE 115-a. For example, the base station 105-a may transmit DCI that includes one or two bits indicating to which transmission the backoff period 335 is to be applied.

The backoff period 335 may be predetermined and known to the base station 105-a and the UE 115-a. Alternatively, base station 105-a or another network entity may configure the backoff period 335. In some examples, the base station 105-a may configure the set of backoff periods 335 and may transmit the set to the UE115-a via an RRC signal or a MAC CE. In such an example, the base station 105-a may send an indication to the UE115-a as to which backoff period 335 to select from the set. For example, the indication may be included in DCI associated with CSI-RS trigger 305, or in DCI associated with uplink grant 320, or by DCI not associated with either CSI-RS trigger 305 or uplink grant 320. In some examples, the UE115-a may determine the backoff period 335 from the set of backoff periods 335 by identifying a field in one of the DCIs mentioned above.

In some examples, the UE115-a and the base station 105-a may reconfigure the slot in which the collision is set to occur (e.g., slot n +3) such that both the CSI-RS310 and the uplink data 325 can be successfully transmitted. For example, the UE115-a or the base station 105-a may determine a number of symbols for uplink transmission and may perform rate matching based on the total amount of CSI-RS resources. For example, in a configuration including 32 ports, slot n +3 may be configured to have three symbols corresponding to PDCCH, four symbols for CSI-RS310, one symbol for the gap period, and the remaining six symbols may be reserved for PUSCH, SRS, PUCCH, and uplink DMRS. The configuration may be indicated by a downlink control signal (e.g., DCI). The downlink signal containing an indication of the configuration may be determined based on which signal is received later. For example, if the UE115-a receives the aperiodic CSI-RS trigger 305 before receiving the uplink grant 320, an indication of the slot configuration may be included in the DCI corresponding to the uplink grant 320. Similarly, if the CSI-RS310 may be semi-persistently scheduled and configured prior to the uplink grant 320, an indication of the slot configuration may be included in the DCI corresponding to the uplink grant 320. Alternatively, if the UE115-a receives the uplink grant 320 before receiving the semi-persistent CSI-RS trigger 305, an indication of the slot configuration may be included in the DCI corresponding to the semi-persistent CSI-RS trigger 305. In some cases, the base station 105-a may transmit DCI or other downlink control signal that includes an indication of a slot configuration that does not correspond to either the uplink grant 320 or the CSI-RS trigger 305. Such a separate DCI or downlink control signal may be transmitted without determining which of the CSI-RS trigger 305 and the uplink grant 320 was first received by the UE 115-a.

In some examples, CSI-RS310 may be multiplexed into a first portion of a slot (e.g., slot n +3) in which collisions are set to occur. For example, the CSI-RS310 may be multiplexed with the PDCCH portion of slot n +3 using frequency division multiplexing, FDM, TDM, or Code Division Multiplexing (CDM). In some cases, the resource configuration for multiplexing the CSI-RS310 may be received in a downlink control signal (e.g., DCI). For example, if the UE115-a receives the CSI-RS trigger 305 before receiving the uplink grant 320, the PDCCH configuration may be included in the DCI corresponding to the uplink grant 320. Alternatively, if the UE115-a receives the uplink grant 320 before receiving the CSI-RS trigger 305, the PDCCH configuration may be included in the DCI corresponding to the CSI-RS trigger 305. In some cases, the base station 105-a may transmit DCI or other downlink control signal that includes a PDCCH configuration that does not correspond to either the uplink grant 320 or the CSI-RS trigger 305. Such a separate DCI or downlink control signal may be transmitted without determining which of the CSI-RS trigger 305 and the uplink grant 320 was first received by the UE 115-a.

Fig. 4 illustrates an example of a wireless communication timing configuration 400 that supports a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the disclosure. In some examples, the wireless communication timing configuration 400 may implement aspects of the wireless communication system 100. The wireless communication timing configuration 400 may relate to aspects of the techniques described with reference to fig. 1-3 and may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1-3).

In some examples, the base station 105-a and the UE115-a may be configured to utilize periodic CSI-RS. In such a case, the base station 105-a may transmit the CSI-RS at regular intervals. For example, the base station 105-a may transmit the CSI-RS405 during a time slot (e.g., time slot n) and may transmit the CSI-RS 410 at another time slot (e.g., time slot n +3) after a time period (e.g., time period 415). The period 415 may be equal to a number of time slots (e.g., 3 time slots) or a set amount of time independent of the number of time slots. The CSI-RS405 may be a first instance of a periodic CSI-RS and the CSI-RS 410 may be a second instance of a periodic CSI-RS. The periodic CSI-RS may be initiated by a trigger received in a downlink control signal (e.g., a higher layer signal such as an RRC signal or MAC CE) and may be automatically transmitted at each time period 415 until disabled.

In some examples, the base station 105-a and the UE115-a may be configured to utilize semi-persistent CSI-RS. In such a case, the base station 105-a may transmit the CSI-RS at regular intervals. However, the base station 105-a may turn on and off the periodic CSI-RS transmission more frequently than the periodic CSI-RS, for example. Similar to the periodic CSI-RS, the base station 105-a may transmit the CSI-RS405 in slot n, and after a period 415 (e.g., 3 slots), the base station 105-a may then transmit the CSI-RS 410 in slot n + 3. In a semi-persistent CSI-RS configuration, the base station 105-a may send a semi-persistent CSI-RS trigger 440 in a previous slot. The first instance of the CSI-RS405 after the CSI-RS trigger 440 may occur after a time delay X after the CSI-RS trigger 440, and subsequent instances of the CSI-RS 410 may occur periodically according to a time period 415 until a subsequent semi-persistent CSI-RS trigger or indicator turns off the semi-persistent CSI-RS transmission.

In some examples, the UE115-a may perform measurements corresponding to the periodic or aperiodic CSI-RS405, 410 and may send CSI reports 430 associated with the measurements. CSI reporting 430 may be configured to occur periodically, and the periodicity for CSI reporting 430 may be different from CSI-RS period 415. Alternatively, CSI reporting 430 may be configured to occur after CSI-RS transmission 405, 410. For example, the UE115-a may determine a timing delay Y435 between receiving the CSI report trigger 465 and sending the CSI report 430. The timing delay Y435 may be equal to a number of slots (e.g., at least one slot) and may be configured via a downlink control signal (e.g., the CSI-RS trigger 440 or a higher layer signal such as an RRC signal or a MAC CE). In some cases, timing delay Y435 may be equal to an amount of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). Alternatively, the UE115-a may receive a separate downlink control signal, which may include a CSI reporting trigger that initiates the CSI report 430. Thus, if UE115-a receives CSI report trigger 465 in slot n +4 and Y435 is equal to one slot, UE115-a may send CSI report 430 in slot n + 5.

In some examples, the base station 105-a may transmit the uplink grant 445 during a time slot (e.g., time slot n + 1). The uplink grant 445 may indicate resources on which the UE115-a may transmit uplink data 450. UE115-a may send uplink data 450 after timing delay K2455. The timing delay K2455 may be equal to a number of slots (e.g., one or more slots) following the slot in which the uplink grant 445 is received (e.g., slot n + 1). In some cases, timing delay K2455 may be equal to an amount of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). Thus, if UE115-a receives uplink grant 445 in time slot n +1 and timing delay K2455 equals two time slots, UE115-a may transmit uplink data 450 at time slot n + 3. The timing delay K2455 may be included in a downlink control signal (e.g., uplink grant 445 or a higher layer signal such as an RRC signal or MAC CE).

As described above, the uplink data 450 and the CSI-RS 410 may collide in a single slot (e.g., slot n + 3). For example, as described above with respect to fig. 3, the UE115-a may identify a pending conflict and may determine a communication configuration to resolve the conflict. For example, the UE115-a may refrain from transmitting the uplink data 450, allowing the UE115-a to receive the CSI-RS 410 without collision. The base station 105-a may send a NACK signal to the UE115-a requesting retransmission of the uplink data 450. In some examples, the base station 105-a may refrain from transmitting any colliding instances of the periodic or semi-persistent CSI-RS405, 410, allowing the UE115-a to transmit uplink data 450 during slot n +3 without collision. In such an example, the UE115-a may determine suppression of the CSI-RS 410 and may not desire to receive the CSI-RS 410.

In some examples, the UE115-a and the base station 105-a may dynamically determine whether to suppress the CSI-RS 410 or the uplink data 450. In some examples, the UE115-a and the base station 105-a may select which transmission to suppress based on which transmission is configured later. For example, the base station 105-a may suppress the CSI-RS 410 if the semi-persistent CSI-RS trigger 440 is received at the UE115-a before the uplink grant 445 (e.g., during a time slot before n +1) and the uplink grant 445 is received at the UE115-a later (e.g., during time slot n + 1). Alternatively, the UE115-a may suppress the uplink data 450 if the semi-periodic CSI-RS trigger 440 is received later than the uplink grant 420. In some examples, the rules may be predefined such that both UE115-a and base station 105-a are aware of the rules. Alternatively, base station 105-a may determine which transmission to suppress and may indicate to UE115-a which transmission to suppress. For example, the base station 105-a may send an indicator (e.g., in the uplink grant 445, CSI-RS trigger 440, or in a separate DCI message) that includes one or two bits to indicate which transmission is to be suppressed.

In some examples, transmission backoff may be applied to one of CSI-RS 410 or uplink data 450. That is, one of the transmissions may be rolled back and the other transmission allowed to be sent within a time slot (e.g., time slot n +3) without collision. In some examples, the UE115-a may determine and apply the backoff period 460 to the uplink data 450, allowing the base station 105-a to transmit the CSI-RS310 during slot n +3 without colliding with the number of uplinks 450. Alternatively, base station 105-a may determine backoff period 460 and apply it to CSI-RS 410. In such an example, the UE115-a may transmit uplink data 450 during slot n +3, and the base station 105-b may transmit the CSI-RS 410 after the backoff period 460 during a later slot (e.g., slot n + 4).

In some examples, the UE115-a and the base station 105-a may dynamically determine whether to apply the backoff period 460 to the CSI-RS 410 or the uplink data 450. In some examples, the UE115-a and the base station 105-a may select to which transmission to apply the backoff period 460 based on which transmission is configured later. For example, if the semi-persistent CSI-RS trigger 440 is received first (e.g., during slot n) at the UE115-a and the uplink grant 445 is received later (e.g., during slot n +1) at the UE115-a, the base station 105-a may apply a backoff period 460 to the semi-persistent CSI-RS 410. In some examples, the base station 105-a may apply a backoff period 460 to each instance of the periodic or semi-persistent CSI-RS following the time slot in which the collision occurred. Alternatively, if the semi-persistent CSI-RS trigger 440 is received later than the uplink grant 445, the UE115-a may apply a backoff period 460 to the uplink data 450.

In some examples, the rules may be predefined such that both UE115-a and base station 105-a are aware of the rules. Alternatively, base station 105-a may determine to apply backoff period 460 to one of the transmissions and may indicate the determination to UE 115-a. For example, the base station 105-a may send an indicator (e.g., in the uplink grant 445, CSI-RS trigger 440, or in a separate DCI message) that includes one or two bits to indicate to which transmission the backoff period 460 is to be applied.

The backoff period 460 may be predetermined and known to the base station 105-a and the UE 115-a. Alternatively, base station 105-a or another network entity may configure the backoff period 335. In some examples, the base station 105-a may configure the set of backoff periods (e.g., via a downlink control signal such as an RRC signal or MAC CE). In such an example, the base station 105-a may send an indication to the UE115-a as to which backoff period 460 to select from the set. For example, the indication may be included in signaling associated with a semi-persistent or periodic CSI-RS configuration, in DCI associated with a semi-persistent CSI-RS trigger 440, in DCI associated with an uplink grant 450, or by DCI not associated with either a semi-persistent CSI-RS trigger 440 or an uplink grant 445. In some examples, the UE115-a may determine the backoff period 460 from the set of backoff periods 460 by identifying a field in one of the DCIs mentioned above.

In some examples, the UE115-a and the base station 105-a may reconfigure the slot in which the collision is set to occur (e.g., slot n +3) such that both the CSI-RS 410 and the uplink data 450 can be successfully transmitted. For example, the UE115-a or the base station 105-a may determine a number of symbols for uplink transmission and may perform rate matching based on the total amount of CSI-RS resources. For example, in a configuration including 32 ports, then slot n +3 may be configured to have three symbols corresponding to PDCCH, four symbols for CSI-RS 410, one symbol for the gap period, and the remaining six symbols may be reserved for PUSCH, SRS, PUCCH, and uplink DMRS. The configuration may be indicated by a downlink control signal (e.g., DCI). The downlink signal containing an indication of the configuration may be determined based on which signal is received later. For example, if the UE115-a receives the semi-persistent CSI-RS trigger 440 before receiving the uplink grant 445, an indication of the slot configuration may be included in the DCI corresponding to the uplink grant 445. Alternatively, if the UE115-a receives the uplink grant 445 before receiving the semi-persistent CSI-RS trigger 440, an indication of the slot configuration may be included in the DCI corresponding to the semi-persistent CSI-RS trigger 440. In some cases, the base station 105-a may transmit DCI or other downlink control signal that includes an indication of a slot configuration that does not correspond to either the uplink grant 445 or the semi-persistent CSI-RS trigger 440. Such a separate DCI or downlink control signal may be transmitted without determining which of the semi-persistent CSI-RS trigger 440 and the uplink grant 450 was first received by the UE 115-a.

In some examples, CSI-RS 410 may be multiplexed into a first portion of a slot (e.g., slot n +3) in which collisions are set to occur. For example, the CSI-RS 410 may be multiplexed with the PDCCH portion of slot n +3 using frequency division multiplexing, FDM, TDM, or CDM. In some cases, the resource configuration for multiplexing the CSI-RS 410 may be received in a downlink control signal (e.g., DCI). For example, if the UE115-a receives the semi-persistent CSI-RS trigger 440 before receiving the uplink grant 445, the PDCCH configuration may be included in the DCI corresponding to the uplink grant 445. Alternatively, if the UE115-a receives the uplink grant 445 before receiving the semi-persistent CSI-RS trigger 440, the PDCCH configuration may be included in the DCI corresponding to the semi-persistent CSI-RS trigger 440. In some cases, the base station 105-a may transmit DCI or other downlink control signal that includes a PDCCH configuration that does not correspond to either the uplink grant 445 or the semi-persistent CSI-RS trigger 440. Such a separate DCI or downlink control signal may be transmitted without determining which of the CSI-RS trigger 445 and the uplink grant 440 was first received by the UE 115-a.

Fig. 5 illustrates an example of a wireless communication timing configuration 500 that supports a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the disclosure. In some examples, the wireless communication timing configuration 500 may implement aspects of the wireless communication system 100. The wireless communication timing configuration 500 may relate to aspects of the techniques described with reference to fig. 1-4 and may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1-4).

In some examples, the base station 105-a may transmit the downlink signal 515. The downlink signal 515 may be an aperiodic CSI-RS trigger. The aperiodic CSI-RS trigger may initiate transmission of CSI-RS505 (which may be an aperiodic CSI-RS). Alternatively, the downlink signal 515 may be a periodic CSI-RS. The periodic CSI-RS may be transmitted at a given periodicity (e.g., every 3 slots), and thus CSI-RS505 may be one example of a periodic CSI-RS. In some examples, downlink signal 515 may be a semi-persistent CSI-RS trigger that may turn on periodic transmission of CSI-RS such that CSI-RS505 is periodically received starting with a particular slot (e.g., slot n + 3). In some examples, the base station 105-a may transmit an uplink grant 516 indicating the resources on which the UE115-a may transmit uplink data 510. The uplink grant 516 may include information about the timing after which the UE115-a will send uplink data 510. In some cases, CSI-RS505 (corresponding to downlink signal 515) and uplink data 510 (corresponding to uplink grant 516) may be configured such that a collision occurs in a given time slot (e.g., time slot n + 3).

In some examples, the base station 105-a and the UE115-a may determine a pending conflict in a time slot (e.g., time slot n + 3). In such a case, the base station 105-a and the UE115-a may determine a communication configuration to resolve the conflict, as described in more detail with reference to fig. 3 and 4. Upon receiving the CSI reporting trigger 540, the UE115-a may determine whether to send the CSI report 520 and the timing for sending the CSI report 520. For example, UE115-a may perform measurements corresponding to CSI-RS505 and may send CSI report 520 associated with the measurements. The UE115-a may determine a timing delay Y525 between receiving the CSI report trigger 540 and sending the CSI report 520. The timing delay Y525 may be equal to a number of slots (e.g., at least one slot) and may be configured by a downlink control signal (e.g., CSI-RS trigger 515, CSI report trigger 540, or a higher layer signal such as an RRC signal or MAC CE). In some cases, timing delay Y525 may be equal to an amount of time independent of the number of slots (e.g., a number of symbol periods or microseconds, etc.). Thus, if UE115-a receives CSI report trigger 540 in slot n +4 and Y525 equals one slot, UE115-a may send CSI report 520 in slot n + 5.

In some examples, CSI-RS505 may be aperiodic and base station 105-a may suppress CSI-RS 505. In some examples, CSI-RS505 may be a periodic or semi-persistent CSI-RS, and base station 105-a may suppress one or more instances of CSI-RS505 that are scheduled to collide with uplink data 510. In such a case, the UE115-a may refrain from sending the CSI-RS report 520. In addition, the base station 105-a may avoid detecting the CSI-RS report in a previously scheduled timing (e.g., slot n + 5). Alternatively, if the base station 105-a suppresses the CSI-RS505, the UE115-a may perform CSI measurements on a CSI-RS configuration that does not include the CSI-RS 505. For example, the UE115-a may determine the most recent instance of the CSI-RS. If the downlink signal 515 corresponds to an aperiodic CSI-RS transmission, the UE115-a may determine whether the aperiodic CSI-RS transmission has similar characteristics (e.g., ports, frequency bands, etc.), and may send the CSI report 520 based on measurements made at the previous instance of the CSI-RS. In such an example, the base station 105-a may receive the CSI report 520 relative to the current reference slot.

In some examples, CSI-RS505 may be a semi-persistent CSI-RS or an aperiodic CSI-RS, and one or more instances may be suppressed or ignored. However, the UE115-a may receive one or more other instances of the periodic or semi-persistent CSI-RS 505. In such an example, the UE115-a may have performed CSI measurements corresponding to instances previously received within the current periodic or semi-persistent CSI-RS configuration. For example, the downlink signal 515 may be a first instance of a currently configured CSI-RS configuration. UE115-a may determine that CSI-RS505 has been suppressed to avoid collision with uplink data 510, but may perform CSI measurements corresponding to periodic or semi-persistent CSI-RS instances received in downlink signal 515 and may send CSI report 520 in slot n +5 as scheduled. Alternatively, in some examples, the periodic or semi-persistent CSI-RS configuration may include six instances of CSI-RS (not shown), and instances four and five may collide with uplink data 510. In such an example, the UE115-a may ignore CSI-RS instances four and five (e.g., not perform measurements for CSI-RS instances four and five), but may perform CSI measurements corresponding to instances one, two, three, and six. In such a case, the payload for CSI-RS report 520 may remain unchanged, and base station 105-a may expect, receive, and decode CSI report 520 at the scheduled timing (e.g., slot n + 5).

In some examples, the aperiodic, periodic, or semi-persistent CSI-RS505 may be delayed for the first backoff period 530, as discussed with reference to fig. 3 and 4. In such an example, the UE115-a may delay the CSI report 520 by applying the second backoff period 535. The second backoff period 535 may be based at least in part on the first backoff period 530 and may be additionally based on some additional timing offset. The second backoff period 530 and/or the additional timing offset may be predetermined values known to both the UE115-a and the base station 105-a. Alternatively, base station 105-a may configure the second backoff period 530 and/or additional timing offsets. In some examples, the base station 105-a may indicate the second set of backoff periods 535 to the UE115-a via MAC CE or RRC signaling. The base station 105-a may select one of the set and may indicate the selected backoff period 535 to the UE115-a via a downlink control signal, such as DCI corresponding to the CSI reporting trigger 540, DCI corresponding to the CSI-RS trigger, DCI associated with the uplink grant 516, or DCI not associated with either the CSI reporting trigger 540, the CSI-RS trigger, or the uplink grant 516. In some examples, applying the second timing offset 535 to the CSI report 520 may offset the CSI report 520 by the second timing offset from slot n +5 (e.g., to slot n +6 if the second timing offset 535 is equal to one slot). Additionally, in some examples, subsequent CSI-RS transmissions and CSI reports may also be delayed by the first timing offset 530 and the second timing offset 535, respectively.

Fig. 6 illustrates an example of a wireless communication timing configuration 600 that supports a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the disclosure. In some examples, the wireless communication timing configuration 600 may implement aspects of the wireless communication system 100. The wireless communication timing configuration 600 may relate to aspects of the techniques described with reference to fig. 1-5 and may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1-5). In some examples, the base station 105-a and the UE115-a may be configured to communicate in a carrier aggregation mode. Thus, a base station 105-a and a UE115-a may communicate via more than one Component Carrier (CC), such as CC1-CC 6.

In some examples, the base station 105-a may transmit a downlink signal 615. Base station 105-a may transmit downlink signals 615 via one or more of CCs 1-CC 6. The downlink signal 615 may be an aperiodic CSI-RS trigger. The aperiodic CSI-RS trigger may initiate transmission of CSI-RS605 (which may be an aperiodic CSI-RS). Alternatively, the downlink signal 615 may be a periodic CSI-RS. The periodic CSI-RS may be transmitted at a given periodicity (e.g., every 3 slots), and thus CSI-RS605 may be another example of a periodic CSI-RS. In some examples, the downlink signal 615 may be a semi-persistent CSI-RS trigger that may turn on periodic transmission of CSI-RS such that the CSI-RS605 is received after a given period in a particular slot (e.g., slot n + 3). In some examples, the base station 105-a may transmit an uplink grant 616 indicating resources on which the UE115-a may transmit uplink data 610. The uplink grant 616 may include information about the timing after which the UE115-a will transmit uplink data 610. In some cases, CSI-RS605 (corresponding to downlink signal 615) and uplink data 610 (corresponding to uplink grant 616) may be configured such that a collision occurs in a given time slot (e.g., time slot n + 3).

In some examples, the base station 105-a and the UE115-a may determine a pending conflict in a time slot (e.g., time slot n + 3). In such a case, the base station 105-a and the UE115-a may determine a communication configuration to resolve the conflict, as described in more detail with reference to fig. 3-5. In such an example, the UE115-a may determine whether to send the CSI report 620 and the timing for sending the CSI report 620. For example, the UE115-a may perform measurements corresponding to the CSI-RS605 and may send a CSI report 620 associated with the measurements. The UE115-a may determine a timing delay Y625 between receiving the CSI report trigger 640 and sending the CSI report 620. The timing delay Y625 may be equal to several time slots (e.g., one time slot) and may be configured by a downlink control signal. In some cases, timing delay Y625 may be equal to an amount of time independent of the number of slots. Alternatively, the UE115-a may receive a separate downlink control signal, which may include a CSI reporting trigger that initiates the CSI report 620. Thus, if UE115-a receives CSI report trigger 640 in slot n +4 and Y625 equals one slot, UE115-a may send CSI report 620 in slot n + 5.

In some examples, the CSI-RS605 may be aperiodic and the base station 105-a may suppress the CSI-RS 605. In some examples, CSI-RS505 may be a periodic or semi-persistent CSI-RS, and base station 105-a may suppress one or more instances of CSI-RS505 that are scheduled to collide with uplink data 510. If the CSI-RS605 is aperiodic, the UE115-a may ignore the CSI-RS605 on the first CC group (e.g., CC1) and perform CSI measurements and send CSI reports 620 on the second CC group (e.g., CC 2). UE115-a may ignore one or more instances of semi-persistent CSI-RS605 on a third CC set (e.g., CC3) and may perform CSI measurements and send CSI reports 620 on a fourth CC set (e.g., CC 4). UE115-a may ignore one or more instances of periodic CSI-RS605 on a fifth CC set (e.g., CC5) and may perform CSI measurements and send CSI reports 620 on a sixth CC set (e.g., CC 6). Thus, UE115-a may not make CSI measurements and send CSI reports 620 for CC1, CC3, and CC5, and may perform CSI measurements and send CSI reports 620 for CC2, CC4, and CC 6. In such an example, the payload of CSI report 620 may be reduced according to the number of CCs on which CSI measurements are received, and base station 105-a may expect, receive, and decode CSI report 620 according to the reduced payload size. In some examples, the UE115-a may perform CSI measurements and send CSI reports 620 on CCs 1, CC3, and CC5 corresponding to the most recent CSI-RS configuration relative to the current slot (e.g., slot n + 3). In such a case, the base station 105-a may detect the CSI report 620 according to the most recent CSI-RS configuration relative to slot n + 3.

In some examples, CSI-RS605 may be one of a periodic CSI-RS or a semi-persistent CSI-RS. The UE115-a may ignore one or more instances of the CSI-RS605 on one or more CCs (or the base station 105-a may suppress one or more instances of the CSI-RS 605) and may receive one or more instances of the semi-persistent or aperiodic CSI-RS605 via one or more CCs. For example, UE115-a may receive CSI-RS605 on CC2, CC4, and CC 6. UE115-a may ignore one or more instances of CSI-RS605 on CC1, CC3, and CC 5. Thus, on CC1, CC3, and CC5, UE115-a may perform CSI measurements corresponding to instances previously received within the current CSI-RS configuration and send CSI reports 620 corresponding to these instances.

As discussed with respect to fig. 5, the aperiodic, periodic, or semi-persistent CSI-RS605 may be delayed for a first backoff period 630. In such an example, the UE115-a may delay the CSI report 620 by applying the second backoff period 635. The second backoff period 635 may be based, at least in part, on the first backoff period 630, and may be additionally based on some additional timing offset. The second backoff period 630 and/or additional timing offsets may be predetermined values known to both the UE115-a and the base station 105-a. Alternatively, the base station 105-a may configure the second backoff period 630 and/or additional timing offsets. In some examples, the base station 105-a may indicate the second set of backoff periods 635 to the UE115-a via MAC CE or RRC signaling. The base station 105-a may select one of the set and may indicate the selected backoff period 635 to the UE115-a via a downlink control signal, such as DCI corresponding to a CSI reporting trigger, DCI associated with an uplink grant 616, or DCI not associated with any of a CSI reporting trigger, a CSI-RS trigger, or an uplink grant 616. In such a case, a second timing offset 635 may be applied to CC 1. Additionally, a second timing offset 635 may be applied to CC2-CC6 such that CSI reports 620 are delayed for all CCs by timing offset 635.

In the example timing configurations shown in fig. 3-6, an example timing delay X, Y, K2 and backoff period are given for ease of illustration. It should be appreciated that these timing delays may be defined in any number of ways (e.g., slots, microseconds, or symbol periods) and may be of any duration. Each of these timing delays may be predetermined or configurable via control signaling (e.g., RRC signaling, MAC CE signaling, etc.).

Fig. 7 illustrates an example of a process flow 700 supporting a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the present disclosure. In some examples, the process flow 700 may implement aspects of the wireless communication system 100. The wireless communication timing configuration 700 may relate to aspects of the techniques described with reference to fig. 1-6 and may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1-6).

At 705, a wireless communication device (e.g., UE115-a and/or base station 105-a) may determine configured timing for receiving CSI-RS and sending CSI reports. That is, the wireless communication device may determine a first time slot (in which to trigger the CSI-RS), a second time slot (in which to receive the CSI-RS), and a third time slot (in which to transmit the CSI-RS). The wireless communication device can also determine a CSI-RS resource configuration (e.g., a number of CSI-RS symbols) and a traffic load (e.g., a number of PUSCH symbols) of the colliding uplink data and CSI-RS. At 710, the wireless communication device can determine whether a reporting delay initiated from the CSI-RS trigger exceeds the second time slot by at least a threshold number of time slots. If the reporting delay exceeds a threshold, the wireless communication device may determine that the wireless communication device will have sufficient time to perform CSI measurements and send CSI reports at the scheduled timing even if the CSI-RS is delayed by the first timing offset. Thus, if the reporting delay exceeds the threshold, the wireless communication device can back off one of the CSI-RS or uplink data transmission by the first timing offset and can send the CSI report on schedule at 715.

Alternatively, if the reporting delay does not exceed the threshold, the wireless communication device can determine a number of CSI-RS symbols in the CSI-RS at 720. At 725, the wireless communication device can determine whether the number of CSI-RS symbols exceeds a threshold. If the number of CSI-RS symbols does not exceed a certain threshold, the wireless communication device may multiplex the CSI-RS with a PDCCH region of an uplink-centric slot in which uplink data is scheduled to collide with the CSI-RS at 730. In such a case, the wireless communication device may transmit or receive CSI reports on a schedule. If the number of CSI-RS symbols exceeds the threshold, the wireless communication device may determine the number of PUSCH symbols in uplink data scheduled for a slot in which the CSI-RS is also scheduled 735. At 740, the wireless communication device can determine whether the number of PUSCH symbols exceeds a certain threshold. If the number of PUSCH symbols does not exceed the threshold, the wireless communication device may dynamically configure the slot in which the collision is pending such that both CSI-RS and uplink data may be transmitted without collision. That is, if the number of PUSCH symbols does not exceed the threshold, the uplink-centric slot may be configured with fewer PUSCH symbols and the downlink portion of the slot may be reconfigured to carry CSI-RS. In such a case, the wireless communication device may transmit or receive CSI reports on a schedule.

Alternatively, if the number of PUSCH symbols does not exceed the threshold, the wireless communication device may refrain from transmitting or receiving CSI reports corresponding to the previous CSI-RS, or refrain from transmitting or receiving CSI reports, or apply a first timing offset to the CSI-RS and a second timing offset to the CSI reports. For example, a monitoring window (e.g., a number of slots before and/or after a scheduled slot) may be defined such that the wireless communication device may determine whether the CSI-RS is transmitted or suppressed and, if the CSI-RS is transmitted, whether it is transmitted after the first timing offset or whether it is transmitted on a schedule. If the wireless communication device monitors the CSI-RS during the window, the wireless communication device may determine whether to send the CSI report or send the CSI report after the second timing backoff without receiving additional indication from the network.

Fig. 8 illustrates an example of a process flow 800 supporting a collision handling mechanism for a dynamic TDD system in accordance with various aspects of the present disclosure. In some examples, the process flow 800 may implement aspects of the wireless communication system 100. The wireless communication timing configuration 800 may relate to aspects of the techniques described with reference to fig. 1-7 and may be implemented by a base station 105-a and a UE115-a (which may be examples of corresponding devices described with reference to fig. 1-7).

At 805, the base station 115-b may send a CSI-RS trigger. At 810, the base station 105-b may transmit an uplink grant. In some cases, the UE 115-b may receive a downlink control signal separate from an uplink grant or CSI-RS trigger. The CSI-RS trigger may be configured independently of the uplink grant, or the CSI-RS trigger and the uplink grant may be received in the same time slot or different time slots. At 813, the base station 105-b may send a CSI reporting trigger to the UE 115-b. The CSI reporting trigger may be configured independently of the CSI-RS trigger transmitted at 805 or the uplink grant transmitted at 810. Alternatively, the CSI reporting trigger may be configured and/or received according to the CSI-RS trigger transmitted at 805 and/or the uplink grant transmitted at 810.

At 815, the UE 115-b may identify a pending conflict during the TDD time slot between uplink data associated with the uplink grant received at 810 and CSI-RS associated with the CSI-RS trigger received at 805.

At 820, the UE115-a may determine a communication configuration for the CSI-RS and the uplink data. In some cases, the wireless device (UE 115-b and/or base station 105-b) may refrain from transmitting uplink data for the time slot in which the CSI-RS is transmitted, and the base station 105-b may send a NACK indicating that an uplink grant is not transmitted and requesting the UE 115-b to retransmit the uplink data. In some examples, refraining from transmitting uplink data may be based on determining that the CSI-RS trigger is transmitted after an uplink grant or based on a refraining indication transmitted in a downlink control signal.

In some examples, the base station 105-b may refrain from transmitting the CSI-RS for the time slot, and may transmit an uplink grant in the time slot. In some examples, refraining from transmitting the CSI-RS may be based on determining that the uplink grant is transmitted after the CSI-RS or based on a refraining indication transmitted in a downlink control signal. In addition, the base station 105-b and the UE 115-b may monitor the CSI-RS within a set of slots prior to the slot; and determining whether to report measurements for the CSI-RS based at least in part on the monitoring.

In some examples, the UE 115-b and/or the base station 105-b may determine a backoff period comprising one or more time slots. The base station 105-a may transmit one of the CSI-RS or uplink data in the slot, and may transmit the other of the CSI-RS or uplink data in a second slot determined by applying a backoff period from the slot. In some examples, transmitting one of the CSI-RS or uplink data is based on determining which of the CSI-RS and uplink grant is transmitted after the other, or based on a backoff selection indication transmitted in a downlink control signal. Determining the backoff period may include: transmitting a set of backoff periods via a first downlink control signal; and transmitting a second downlink control signal corresponding to the CSI-RS, the uplink data, or neither the uplink grant nor the CSI-RS; and selecting one of a set of backoff periods based at least in part on the transmitted second downlink control signal. In some cases, the first downlink control signal and the second downlink control signal may include DCI, a medium access control, MAC, CE, or an RRC message. In some cases, the backoff selection indication and the index indicating the backoff period from the set of backoff periods may be transmitted together.

In some cases, one or both of the base station 105-b and the UE 115-b may determine an amount of CSI-RS resources and may adapt a communication configuration for transmitting CSI-RS and uplink data within the time slot. Adapting the configuration may include: determining a number of downlink symbols and a number of uplink symbols within the slot for transmitting the CSI-RS and uplink data in the slot; performing rate matching for uplink data based at least in part on the number of uplink symbols; and transmitting the CSI-RS using the downlink symbol in the slot and transmitting the uplink data using the uplink symbol in the slot.

In some examples, one or both of the UE 115-b and the base station 105-b may determine whether the CSI-RS trigger or the uplink grant is to be transmitted later, and transmitting the CSI-RS and transmitting the uplink data may be based at least in part on the determination. In some examples, transmitting the CSI-RS and transmitting the uplink data in the slot is based at least in part on receiving a downlink control signal separate from an uplink grant or a CSI-RS trigger.

One or both of the UE 115-b and the base station 105-b may determine whether to adapt the communication configuration based at least in part on the amount of resources for uplink data being below a threshold or the amount of frequency resources for CSI-RS and the amount of frequency resources for uplink data.

One or both of the UE 115-b and the base station 105-b may determine whether to multiplex the CSI-RS into the first portion of the slot based at least in part on the amount of resources for the CSI-RS being less than a threshold or the amount of frequency resources for the CSI-RS and the amount of frequency resources for the uplink data.

In some examples, the base station 105-b and the UE 115-b may determine that the CSI-RS is one of a periodic CSI-RS or a semi-persistent CSI-RS, and may determine a backoff period for the CSI-RS. The device may also offset all subsequent transmissions to the CSI-RS by the backoff period.

At 825, the UE 115-b and the base station 105-b may transmit CSI-RS and/or uplink data according to the determined communication configuration. In some examples, one of the devices may identify a downlink control channel transmitted via the first portion of the timeslot and multiplex the CSI-RS into the first portion of the timeslot using one of FDM, CDM, or TDM. The base station 105-b or the UE 115-b may determine an order of transmission of CSI-RS triggers and uplink grants, wherein multiplexing the CSI-RS into the first portion of the slot is based at least in part on the determination. One of the base station 105-b and the UE 115-b may determine that the CSI-RS trigger is transmitted prior to an uplink grant and transmit a downlink control signal corresponding to the uplink grant, wherein multiplexing the CSI-RS into the first portion of the slot is based at least in part on the downlink control signal. Alternatively, the base station 105-b or the UE 115-b may determine that the uplink grant is transmitted prior to the CSI-RS trigger and may transmit a downlink control signal corresponding to the CSI-RS trigger, wherein multiplexing the CSI-RS into the first portion of the slot is based at least in part on the downlink control signal.

At 830, UE 115-b may determine a reporting configuration. The UE 115-b may receive a reporting trigger, which may be received in one of: a downlink control signal corresponding to a CSI-RS trigger, a downlink control signal corresponding to an uplink grant, or a downlink control signal not corresponding to either a CSI-RS trigger or a downlink control signal. In some examples, the UE115-a may refrain from performing measurements corresponding to CSI-RS for a slot on a TDD carrier. In some examples, one of the UE 115-b and the base station 105-b may determine that the TDD carrier is one of a plurality of configured component carriers and may perform measurements of CSI-RSs received in time slots on at least a second component carrier of the plurality of component carriers. In such an example, the UE 115-b may transmit a CSI report for the second component carrier based at least in part on measurements for CSI-RSs received in a slot on the second component carrier. In some examples, the base station 105-b or the UE 115-b may determine that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS for a first backoff period, and may perform measurements of the CSI-RS received in a second slot corresponding to the first backoff period from the slot.

In some cases, the UE 115-b or the base station 105-b may determine that the reporting delay initiated from the CSI-RS trigger does not exceed the second time slot by at least a threshold number of time slots. In such a case, the device may also determine a second backoff period comprising the first backoff period or the reporting delay, and may transmit the CSI report in a third time slot corresponding to the second backoff period from the time slot in which the CSI report was triggered. The second backoff period may be predefined. Alternatively, base station 105-b may transmit a second set of backoff periods in the first downlink control signal and may transmit a second downlink control signal, wherein the second downlink control signal corresponds to one of: an uplink grant, a CSI-RS trigger, or a downlink control signal separate from the uplink grant and the CSI-RS trigger. One of the devices may then select one of a second set of backoff periods based at least in part on the transmitted second downlink signal. In some cases, the first downlink control signal includes a DCI, MAC-CE, or RRC message.

In some cases, one of the base station 105-b and the UE 115-b may determine that a reporting delay initiated from the CSI-RS trigger exceeds the second slot by at least a threshold number of slots, and may transmit the CSI report in a third slot corresponding to the timing delay indicated in the CSI report trigger. In some examples, one of the base station 105-b and the UE 115-b may determine that the TDD carrier is one of a plurality of configured component carriers, may perform measurements of CSI-RS received in a time slot on at least a second component carrier of the plurality of component carriers, and may transmit a CSI report that includes measurements for CSI-RS received in a time slot on at least the second component carrier. The CSI-RS trigger may be configured independently of the uplink grant, or the CSI-RS trigger and the uplink grant may be received in the same time slot or different time slots.

At 835, in some examples, the UE 115-b may send a CSI report corresponding to the CSI-RS that may have been received at 825. In some examples, the UE 115-b or the base station 105-b may refrain from transmitting the CSI report associated with the CSI report trigger. In some examples, the UE115-a may transmit a CSI report associated with a CSI reporting trigger for the TDD carrier based at least in part on measurements of CSI-RSs performed prior to the time slot. The CSI-RS may include an instance of a semi-persistent or periodically configured CSI-RS, and wherein transmitting the CSI report is based at least in part on determining that at least one other instance of the semi-persistent or periodically configured CSI-RS occurs before a reporting slot for the semi-persistent or periodically configured CSI-RS.

Fig. 9 illustrates a block diagram 900 of a wireless device 905 supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The wireless device 905 may be an example of aspects of a User Equipment (UE)115 or a base station 105 as described herein. The wireless device 905 may include a receiver 910, a communication manager 915, and a transmitter 920. The wireless device 905 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

Receiver 910 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to collision handling mechanisms for dynamic TDD systems, etc.). Information may be passed to other components of the device. The receiver 910 may be an example of aspects of the transceiver 1235 described with reference to fig. 12. Receiver 910 can utilize a single antenna or a group of antennas. The communication manager 915 may be an example of aspects of the communication manager 1215 described with reference to fig. 12.

The communication manager 915 and/or at least some of its various subcomponents may be implemented in hardware, software executed by a processor, firmware or any combination thereof. If implemented in software executed by a processor, the functions of the communication manager 915 and/or at least some of its various subcomponents may be performed by a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in this disclosure.

The communication manager 915 and/or at least some of its various subcomponents may be physically located at various locations, including being distributed such that some of the functionality is implemented by one or more physical devices at different physical locations. In some examples, the communication manager 915 and/or at least some of its various subcomponents may be separate and distinct components in accordance with various aspects of the present disclosure. In other examples, the communication manager 915 and/or at least some of its various subcomponents may be combined with one or more other hardware components (including, but not limited to, an I/O component, a transceiver, a network server, another computing device, one or more other components described in this disclosure, or a combination thereof), in accordance with various aspects of the present disclosure.

The communication manager 915 may perform the following operations: identifying, for a time slot of a TDD carrier, a pending collision between a channel state information reference signal (CSI-RS) corresponding to a CSI-RS trigger and uplink data corresponding to an uplink grant; determining a communication configuration for the CSI-RS and uplink data based on the pending conflict; and determining a CSI reporting configuration based on the communication configuration.

Transmitter 920 may transmit signals generated by other components of the device. In some examples, the transmitter 920 may be collocated with the receiver 910 in a transceiver module. For example, the transmitter 920 may be an example of aspects of the transceiver 1235 described with reference to fig. 12. Transmitter 920 may utilize a single antenna or a group of antennas.

Fig. 10 shows a block diagram 1000 of a wireless device 1005 supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The wireless device 1005 may be an example of aspects of the wireless device 905 or the UE115 or base station 105 as described with reference to fig. 9. The wireless device 1005 may include a receiver 1010, a communication manager 1015, and a transmitter 1020. The wireless device 1005 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

Receiver 1010 can receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to collision handling mechanisms for dynamic TDD systems, etc.). Information may be passed to other components of the device. The receiver 1010 may be an example of aspects of the transceiver 1235 described with reference to fig. 12. Receiver 1010 may utilize a single antenna or a group of antennas.

The communication manager 1015 may be an example of aspects of the communication manager 1215 described with reference to fig. 12. The communication manager 1015 may also include a conflict identification component 1025, a communication configuration component 1030, and a reporting component 1035.

The collision identification component 1025 can identify a pending collision between the CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant for a time slot of the TDD carrier.

Communication configuration component 1030 may determine a communication configuration for the CSI-RS and uplink data based on the pending conflict. The communication configuration component 1030 may receive a CSI reporting trigger, wherein the CSI reporting trigger is received in one of: a downlink control signal corresponding to a CSI-RS trigger, a downlink control signal corresponding to an uplink grant, or a downlink control signal not corresponding to either a CSI-RS trigger or a downlink control signal. The communication configuration component 1030 may transmit a NACK indicating that the uplink grant was not transmitted and requesting retransmission of the uplink data. Communication configuration component 1030 may transmit an uplink grant in the time slot, transmit one of CSI-RS or uplink data in the time slot, transmit the other of CSI-RS or uplink data in a second time slot determined by applying a backoff period from the time slot, and/or determine an amount of CSI-RS resources corresponding to the CSI-RS. Based on the determined amount of CSI-RS resources, communication configuration component 1030 may transmit CSI-RS using downlink symbols in the slot and uplink data using uplink symbols in the slot.

Communication configuration component 1030 may transmit a downlink control signal separate from an uplink grant or CSI-RS trigger, wherein transmitting CSI-RS and transmitting uplink data in the time slot is based on the downlink control signal. Communication configuration component 1030 may determine whether to adapt a communication configuration based on the amount of resources for uplink data being below a threshold or the amount of frequency resources for CSI-RS and the amount of frequency resources for uplink data. Communication configuration component 1030 may identify a downlink control channel transmitted via the first portion of the time slot, transmit a CSI report associated with a CSI report trigger for the TDD carrier based on measurements of the CSI-RS performed prior to the time slot, and/or transmit the CSI-RS in the time slot. Communication configuration component 1030 may transmit a CSI report for the second component carrier based on measurements for CSI-RSs received in a slot on the second component carrier.

Communication configuration component 1030 may determine that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period, determine that a reporting delay from the CSI-RS trigger does not exceed a second slot by at least a threshold number of slots, and/or transmit the CSI report in a third slot corresponding to a second backoff period from a slot in which the CSI report is triggered. The communication configuration component 1030 may transmit a second downlink control signal, wherein the second downlink control signal corresponds to one of: an uplink grant, a CSI-RS trigger, or a downlink control signal separate from the uplink grant and the CSI-RS trigger.

In some examples, communication configuration component 1030 may determine that the TDD carrier is one component carrier of a set of configured component carriers, determine that the CSI-RS is one of a periodic CSI-RS or a semi-persistent CSI-RS, and offset all subsequent transmissions of the CSI-RS by a backoff period. In some cases, the first downlink control signal and the second downlink control signal include DCI, a MAC Control Element (CE), or a Radio Resource Control (RRC) message. In some cases, adapting the communication configuration for transmitting the CSI-RS and the uplink data within the time slot comprises: a number of downlink symbols and a number of uplink symbols are determined for transmitting CSI-RS and uplink data in the slot within the slot. In some cases, the first downlink control signal includes a DCI, a MAC CE, or an RRC message. In some cases, the CSI-RS trigger is configured independently of the uplink grant. In some cases, the CSI-RS trigger and the uplink grant are received in the same time slot. In some cases, the CSI-RS trigger and the uplink grant are received in different time slots. In some cases, the CSI-RS is one of a periodic CSI-RS, an aperiodic CSI-RS, or a semi-persistent CSI-RS, and the CSI-RS trigger is included in one of a downlink control signal, a MAC CE, or an RRC signal.

Reporting component 1035 may determine a CSI reporting configuration based on the communication configuration and determine whether to report measurements for the CSI-RS based on the monitoring. Reporting component 1035 may determine that a reporting delay initiated from the CSI-RS trigger exceeds the second slot by at least a threshold number of slots, transmit a CSI report in a third slot corresponding to the timing delay indicated in the CSI reporting trigger, and transmit a CSI report including measurements for the CSI-RS received in the slot over at least the second component carrier.

The transmitter 1020 may transmit signals generated by other components of the device. In some examples, the transmitter 1020 may be collocated with the receiver 1010 in a transceiver module. For example, the transmitter 1020 may be an example of aspects of the transceiver 1235 described with reference to fig. 12. The transmitter 1020 may utilize a single antenna or a group of antennas.

Fig. 11 shows a block diagram 1100 of the communication manager 1115 supporting a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The communication manager 1115 may be an example of aspects of the communication manager 915, the communication manager 1015, or the communication manager 1215 described with reference to fig. 9, 10, and 12. The communication manager 1115 may include a conflict identification component 1120, a communication configuration component 1125, a reporting component 1130, a suppression component 1135, a monitoring component 1140, a fallback component 1145, a ranking component 1150, a rate matching component 1155, a multiplexing component 1160, and a measurement component 1165. Each of these modules may communicate with each other directly or indirectly (e.g., via one or more buses).

Collision identification component 1120 may identify a pending collision between the CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant for a time slot of the TDD carrier.

The communication configuration component 1125 can determine a communication configuration for the CSI-RS and the uplink data based on the pending conflict. The communication configuration component 1125 may transmit a CSI reporting trigger, wherein the CSI reporting trigger is transmitted in one of: a downlink control signal corresponding to a CSI-RS trigger, a downlink control signal corresponding to an uplink grant, or a downlink control signal not corresponding to either a CSI-RS trigger or a downlink control signal. The communication configuration component 1125 may transmit a NACK indicating that the uplink grant was not transmitted and requesting retransmission of the uplink data, or may transmit the uplink grant in the time slot. The communication configuration component 1125 may transmit one of CSI-RS or uplink data in the time slot and the other of CSI-RS or uplink data in a second time slot determined by applying a backoff period from the time slot.

The communication configuration component 1125 may determine an amount of CSI-RS resources in which to transmit CSI-RS using downlink symbols and to transmit uplink data using uplink symbols in the slot, and/or transmit downlink control signals separate from uplink grants or CSI-RS triggers, wherein transmitting CSI-RS and transmitting uplink data in the slot is based on downlink control signals. The communication configuration component 1125 may determine whether to adapt a communication configuration identifying a downlink control channel transmitted via the first portion of the time slot based on the amount of resources for uplink data being below a threshold or the amount of frequency resources for CSI-RS and the amount of frequency resources for uplink data.

The communication configuration component 1125 may transmit a CSI report associated with a CSI report trigger for a TDD carrier based on measurements of CSI-RSs performed prior to the time slot, and/or transmit CSI-RSs in the time slot. The communication configuration component 1125 may transmit a CSI report for a second component carrier based on measurements for CSI-RSs received in a slot on the second component carrier. The communication configuration component 1125 may also determine that the communication configuration for the CSI-RS corresponds to a delay of the CSI-RS that is a first backoff period.

In some cases, communication configuration component 1125 may determine that a reporting delay from a CSI-RS trigger does not exceed a second time slot by at least a threshold number of time slots, and may transmit a CSI report in a third time slot corresponding to a second backoff period from the time slot in which the CSI report is triggered. The communication configuration component 1125 may transmit a second downlink control signal, wherein the second downlink control signal corresponds to one of: an uplink grant, a CSI-RS trigger, or a downlink control signal separate from the uplink grant and the CSI-RS trigger.

The communication configuration component 1125 may determine that the TDD carrier is one of a set of configured component carriers, determine that the CSI-RS is one of a periodic CSI-RS or a semi-persistent CSI-RS, and offset all subsequent transmissions of the CSI-RS by a backoff period. In some cases, the first downlink control signal and the second downlink control signal include DCI, MAC CE, or RRC messages. In some cases, adapting a communication configuration for transmitting CSI-RS and uplink data within the time slot, wherein adapting the communication configuration comprises: a number of downlink symbols and a number of uplink symbols are determined for transmitting CSI-RS and uplink data in the slot within the slot. In some cases, the first downlink control signal includes a DCI, a MAC CE, or an RRC message. In some cases, the CSI-RS trigger is configured independently of the uplink grant. In some cases, the CSI-RS trigger and the uplink grant are received in the same time slot. In some cases, the CSI-RS trigger and the uplink grant are received in different time slots. In some cases, the CSI-RS is one of a periodic CSI-RS, an aperiodic CSI-RS, or a semi-persistent CSI-RS, and the CSI-RS trigger is included in one of a downlink control signal, a MAC CE, or an RRC signal.

Reporting component 1130 may determine a CSI reporting configuration based on the communication configuration, determine whether to report measurements for the CSI-RS based on the monitoring, determine that a reporting delay initiated from the CSI-RS trigger exceeds the second slot by at least a threshold number of slots, transmit a CSI report in a third slot corresponding to a timing delay indicated in the CSI reporting trigger, and transmit a CSI report including measurements for the CSI-RS received in the slots on at least the second component carrier.

Suppression component 1135 may suppress transmission of uplink data within the time slot, suppress transmission of CSI-RS within the time slot, and suppress transmission of CSI reports associated with the CSI reporting trigger. In some cases, suppressing transmission of uplink data is based on determining that the CSI-RS trigger is transmitted after an uplink grant or based on a suppression indication transmitted in a downlink control signal. In some cases, suppressing transmission of the CSI-RS is based on determining that the uplink grant is transmitted after the CSI-RS or based on a suppression indication transmitted in a downlink control signal.

Monitoring component 1140 may monitor the CSI-RS in a set of slots preceding the slot. Backoff component 1145 may determine a backoff period comprising one or more time slots and may transmit a second downlink control signal corresponding to the CSI-RS, the uplink data, or neither the uplink grant nor the CSI-RS. A backoff component 1145 may select one of a set of backoff periods based on the transmitted second downlink control signal, and may determine a second backoff period comprising the first backoff period or the reporting delay, and may select one of the second set of backoff periods based on the transmitted second downlink control signal. Backoff component 1145 may determine a backoff period for the CSI-RS. In some cases, determining the backoff period further comprises: a set of backoff periods is transmitted via a first downlink control signal. In some cases, the backoff selection indication and an index indicating a backoff period from the set of backoff periods are transmitted together. In some cases, the second backoff period is predefined. In some cases, determining the second backoff period further comprises: transmitting a second set of backoff periods in the first downlink control signal.

Ordering component 1150 may transmit one of CSI-RS or uplink data based on determining which of the CSI-RS and uplink grant is transmitted after the other, or based on a backoff selection indication transmitted in a downlink control signal. Ordering component 1150 may determine whether the CSI-RS trigger or the uplink grant is transmitted later, wherein transmitting the CSI-RS and transmitting the uplink data is based on the determination. Ordering component 1150 may determine an order of transmission of CSI-RS triggers and uplink grants, wherein multiplexing CSI-RS into the first portion of the slot is based on the determination. Ordering component 1150 may determine that the CSI-RS trigger is transmitted before the uplink grant or that the uplink grant is transmitted before the CSI-RS trigger. In some cases, the CSI-RS may include an instance of a semi-persistent or periodically configured CSI-RS, and wherein transmitting the CSI report is based on determining that at least one other instance of the semi-persistent or periodically configured CSI-RS occurs before a reporting slot for the semi-persistent or periodically configured CSI-RS.

The rate matching component 1155 may perform rate matching for the uplink data based on the number of uplink symbols. Multiplexing component 1160 may multiplex the CSI-RS into the first portion of the slot using one of FDM, code division multiplexed CDM, or time division multiplexed TDM. Multiplexing component 1160 can transmit a downlink control signal corresponding to an uplink grant, wherein multiplexing the CSI-RS into the first portion of the slot is based on the downlink control signal. Multiplexing component 1160 may transmit a downlink control signal corresponding to a CSI-RS trigger, wherein multiplexing the CSI-RS into the first portion of the slot is based on the downlink control signal, and/or transmit a downlink control signal not corresponding to an uplink grant or a CSI-RS trigger, wherein multiplexing the CSI-RS into the first portion of the slot is based on the downlink control signal. Multiplexing component 1160 may determine whether to multiplex the CSI-RS into the first portion of the slot based on the amount of resources for the CSI-RS being less than a threshold or the amount of frequency resources for the CSI-RS and the amount of frequency resources for the uplink data.

Measurement component 1165 may refrain from performing measurements corresponding to CSI-RSs for slots on the TDD carrier. In some examples, measurement component 1165 may perform measurements of CSI-RSs received in a slot on at least a second component carrier of the set of component carriers and perform measurements of CSI-RSs received in a second slot corresponding to a first backoff period from the slot.

Fig. 12 shows a diagram of a system 1200 including a device 1205 that supports a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The device 1205 may be an example of, or a component that includes: wireless device 905, wireless device 1005, or UE115 as described above (e.g., with reference to fig. 9 and 10). Device 1205 may include components for two-way voice and data communications, including components for sending and receiving communications, including: UE communications manager 1215, processor 1220, memory 1225, software 1230, transceiver 1235, antenna 1240, and I/O controller 1245. These components may be in electronic communication via one or more buses, such as bus 1210. The device 1205 may communicate wirelessly with one or more base stations 105.

Processor 1220 may include intelligent hardware devices (e.g., a general purpose processor, a DSP, a Central Processing Unit (CPU), a microcontroller, an ASIC, an FPGA, a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1220 may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into processor 1220. The processor 1220 may be configured to execute computer-readable instructions stored in the memory to perform various functions (e.g., functions or tasks to support a collision handling mechanism for a dynamic TDD system).

The memory 1225 may include Random Access Memory (RAM) and Read Only Memory (ROM). The memory 1225 may store computer-readable, computer-executable software 1230 comprising instructions that, when executed, cause the processor to perform various functions described herein. In some cases, memory 1225 may contain, among other things, a basic input/output system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

Software 1230 may include code for implementing aspects of the present disclosure, including code for supporting a collision handling mechanism for a dynamic TDD system. The software 1230 may be stored in a non-transitory computer-readable medium, such as a system memory or other memory. In some cases, the software 1230 may not be directly executable by a processor, but may cause a computer (e.g., when compiled and executed) to perform functions described herein.

The transceiver 1235 may communicate bi-directionally via one or more antennas, wired or wireless links as described above. For example, the transceiver 1235 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1235 may also include a modem to modulate packets and provide the modulated packets to the antennas for transmission, as well as demodulate packets received from the antennas.

In some cases, a wireless device may include a single antenna 1240. However, in some cases, a device may have more than one antenna 1240, which may be capable of concurrently sending or receiving multiple wireless transmissions.

I/O controller 1245 may manage input and output signals for device 1205. I/O controller 1245 may also manage peripheral devices that are not integrated into device 1205. In some cases, I/O controller 1245 may represent a physical connection or port to an external peripheral device. In some cases, I/O controller 1245 can utilize a processor such as

Or another known operating system. In other cases, I/O controller 1245 can represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I/O controller 1245 may be implemented as part of a processor. In some cases, a user can interact with device 1205 via I/O controller 1245 or via hardware components controlled by I/O controller 1245.

Fig. 13 illustrates a diagram of a system 1300 including a device 1305 that supports a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The device 1305 may be an example of or a component that includes: the wireless device 1005, the wireless device 1105, or the base station 105 as described above (e.g., with reference to fig. 10 and 11). Device 1305 may include components for two-way voice and data communications, including components for sending and receiving communications, including: a base station communications manager 1315, a processor 1320, a memory 1325, software 1330, a transceiver 1335, an antenna 1340, a network communications manager 1345, and an inter-station communications manager 1350. These components may be in electronic communication via one or more buses, such as bus 1310. The device 1305 may communicate wirelessly with one or more UEs 115.

Processor 1320 may include intelligent hardware devices (e.g., general purpose processors, DSPs, CPUs, microcontrollers, ASICs, FPGAs, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combinations thereof). In some cases, the processor 1320 may be configured to operate the memory array using a memory controller. In other cases, the memory controller may be integrated into the processor 1320. The processor 1320 may be configured to execute computer readable instructions stored in the memory to perform various functions (e.g., functions or tasks to support a collision handling mechanism for a dynamic TDD system).

Memory 1325 may include RAM and ROM. The memory 1325 may store computer-readable, computer-executable software 1330 comprising instructions that, when executed, cause the processor to perform various functions described herein. In some cases, memory 1325 may contain, among other things, a BIOS that may control basic hardware or software operations (such as interaction with peripheral components or devices).

Software 1330 may include code for implementing aspects of the present disclosure, including code for supporting a collision handling mechanism for a dynamic TDD system. The software 1330 may be stored in a non-transitory computer-readable medium, such as a system memory or other memory. In some cases, the software 1330 may not be directly executable by the processor, but may cause the computer (e.g., when compiled and executed) to perform the functions described herein.

The transceiver 1335 may communicate bi-directionally via one or more antennas, wired or wireless links as described above. For example, the transceiver 1335 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1335 may also include a modem to modulate packets and provide the modulated packets to the antennas for transmission, and to demodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1340. However, in some cases, the device may have more than one antenna 1340, which may be capable of sending or receiving multiple wireless transmissions concurrently.

The network communication manager 1345 may manage communication with the core network (e.g., via one or more wired backhaul links). For example, the network communication manager 1345 may manage the transmission of data communications for client devices (such as one or more UEs 115).

The inter-station communication manager 1350 may manage communications with other base stations 105 and may include a controller or scheduler to control communications with UEs 115 in cooperation with other base stations 105. For example, inter-station communication manager 1350 may coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques, such as beamforming or joint transmission. In some examples, the inter-station communication manager 1350 may provide an X2 interface within Long Term Evolution (LTE)/LTE-a wireless communication network technologies to provide communication between base stations 105.

Fig. 14 shows a flow diagram illustrating a method 1400 for a collision handling mechanism for a dynamic TDD system, in accordance with aspects of the present disclosure. The operations of the method 1400 may be implemented by the UE115 or the base station 105, or components thereof, as described herein. For example, the operations of method 1400 may be performed by the communication manager described with reference to fig. 9-11. In some examples, the UE115 or base station 105 may execute sets of codes to control the functional elements of the device to perform the functions described below. Additionally or alternatively, the UE115 or base station 105 may perform aspects of the functions described below using dedicated hardware.

At block 1405, the UE115 or the base station 105 may identify, for a time slot of the TDD carrier, a pending collision between the CSI-RS corresponding to the CSI-RS trigger and uplink data corresponding to the uplink grant. The operations of block 1405 may be performed according to the methods described herein. In some examples, aspects of the operations of block 1405 may be performed by a conflict identification component as described with reference to fig. 9-11.

At block 1410, the UE115 or the base station 105 may determine a communication configuration for the CSI-RS and the uplink data based at least in part on the pending collision. The operations of block 1410 may be performed according to the methods described herein. In some examples, aspects of the operations of block 1410 may be performed by a communication configuration component as described with reference to fig. 9-11.

At block 1415, the UE115 or the base station 105 may determine a CSI reporting configuration based at least in part on the communication configuration and the CSI reporting trigger. The operations of block 1415 may be performed in accordance with the methods described herein. In some examples, aspects of the operations of block 1415 may be performed by a reporting component as described with reference to fig. 9-11.

It should be noted that the above described methods describe possible implementations and that the operations and steps may be rearranged or otherwise modified and that other implementations are possible. Further, aspects from two or more of these methods may be combined.

The techniques described herein may be used for various wireless communication systems such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), single carrier frequency division multiple access (SC-FDMA), and others. The terms "system" and "network" are often used interchangeably. Code Division Multiple Access (CDMA) systems may implement radio technologies such as CDMA2000, Universal Terrestrial Radio Access (UTRA), and the like. CDMA2000 covers IS-2000, IS-95 and IS-856 standards. The IS-2000 version may be generally referred to as CDMA20001X, 1X, etc. IS-856(TIA-856) IS commonly referred to as CDMA20001xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes wideband CDMA (wcdma) and other variants of CDMA. TDMA systems may implement radio technologies such as global system for mobile communications (GSM).

The OFDMA system may implement radio technologies such as Ultra Mobile Broadband (UMB), evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE)802.11(Wi-Fi), IEEE 802.16(WiMAX), IEEE 802.20, flash OFDM, etc. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE-A, NR, and GSM are described in documents from an organization entitled "third Generation partnership project" (3 GPP). CDMA2000 and UMB are described in documents from an organization named "third generation partnership project 2" (3GPP 2). The techniques described herein may be used for the above-mentioned systems and radio technologies, as well as other systems and radio technologies. Although aspects of an LTE or NR system may be described for purposes of example, and LTE or NR terminology is used in much of the description, the techniques described herein are applicable beyond LTE or NR applications.

In LTE/LTE-a networks (including those described herein), the term evolved node b (enb) may be used generally to describe a base station. One or more wireless communication systems described herein may include heterogeneous LTE/LTE-a or NR networks, where different types of enbs provide coverage for various geographic areas. For example, each eNB, next generation node b (gnb), or base station may provide communication coverage for a macro cell, a small cell, or other type of cell. The term "cell" can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on the context.

A base station may include, or may be referred to by those skilled in the art as, a base transceiver station, a radio base station, an access point, a radio transceiver, a node B, an evolved node B (enb), a gNB, a home node B, a home evolved node B, or some other suitable terminology. The geographic coverage area of a base station can be divided into sectors that form only a portion of the coverage area. One or more wireless communication systems described herein may include different types of base stations (e.g., macro cell base stations or small cell base stations). The UEs described herein may be capable of communicating with various types of base stations and network devices, including macro enbs, small cell enbs, gbbs, relay base stations, and so forth. For different technologies, there may be overlapping geographic coverage areas.

A macro cell typically covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions with the network provider. A small cell is a lower power base station than a macro cell, which may operate in the same or different (e.g., licensed, unlicensed, etc.) frequency bands as the macro cell. According to various examples, the small cells may include pico cells, femto cells, and micro cells. For example, a pico cell may cover a small geographic area and may allow unrestricted access by UEs with service subscriptions with the network provider. A femto cell may also cover a small geographic area (e.g., a home) and may provide restricted access by UEs having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG), UEs for users in the home, etc.). The eNB for the macro cell may be referred to as a macro eNB. An eNB for a small cell may be referred to as a small cell eNB, pico eNB, femto eNB, or home eNB. An eNB may support one or more (e.g., two, three, four, etc.) cells (e.g., component carriers).

One or more of the wireless communication systems described herein may support synchronous or asynchronous operation. For synchronous operation, the base stations may have similar frame timing, and transmissions from different base stations may be approximately aligned in time. For asynchronous operation, the base stations may have different frame timing, and transmissions from different base stations may not be aligned in time. The techniques described herein may be used for synchronous operations or asynchronous operations.

The downlink transmissions described herein may also be referred to as forward link transmissions, while the uplink transmissions may also be referred to as reverse link transmissions. Each of the communication links described herein (including, for example, the wireless communication systems 100 and 200 of fig. 1 and 2) may include one or more carriers, where each carrier may be a signal made up of multiple subcarriers (e.g., waveform signals of different frequencies).

The description set forth herein in connection with the appended drawings describes example configurations and is not intended to represent all examples that may be implemented or within the scope of the claims. The term "exemplary" as used herein means "serving as an example, instance, or illustration," and is not "preferred" or "advantageous over other examples. The detailed description includes specific details for the purpose of providing an understanding of the described technology. However, the techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.

In the drawings, similar components or features may have the same reference numerals. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description may be applied to any one of the similar components having the same first reference label irrespective of the second reference label.

Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection with the disclosure herein may be implemented or performed with a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and implementations are within the scope of the disclosure and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. Features for performing functions may also be physically located at various locations, including being distributed such that portions of functions are performed at different physical locations. Further, as used herein (including in the claims), "or" as used in a list of items (e.g., a list of items ending with a phrase such as "at least one of … …" or "one or more of … …") indicates an inclusive list such that, for example, a list of at least one of A, B or C means a, or B, or C, or AB, or AC, or BC, or ABC (i.e., a and B and C). Further, as used herein, the phrase "based on" should not be construed as a reference to a closed set of conditions. For example, an exemplary step described as "based on condition a" may be based on both condition a and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on" is interpreted.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. Non-transitory storage media may be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer-readable media can comprise RAM, ROM, electrically erasable programmable read-only memory (EEPROM), Compact Disc (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes CD, laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

The description herein is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.