阅读说明：本技术 通过不同模式中的dmrs/pbch的定时指示 (Timing indication by DMRS/PBCH in different modes ) 是由 N·阿贝迪尼 M·N·*** S·苏布拉玛尼安 B·萨第齐 骆涛 于 2018-05-02 设计创作，主要内容包括：本公开内容的某些方面涉及用于传送定时信息的方法和装置,所述定时信息跨越物理广播信道(PBCH)的多个冗余版本在其中被发送的传输时间间隔(TTI)进行改变。(Certain aspects of the present disclosure relate to methods and apparatus for communicating timing information that varies across Transmission Time Intervals (TTIs) in which multiple redundancy versions of a Physical Broadcast Channel (PBCH) are transmitted.)

1. A method for wireless communications by a base station, comprising:

determining a first set of one or more bits in a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI;

transmitting a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, the plurality of versions comprising a second set of bits of the timing reference number that do not change for the duration of the TTI; and

providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

2. The method of claim 1, wherein the timing reference number comprises at least one of: a System Frame Number (SFN), an indication of subframe level, an indication of symbol level timing, a Synchronization Signal Block (SSB) index, or an indication of a field.

3. The method of claim 1, wherein different synchronization patterns have different durations of the TTI.

4. The method of claim 3, wherein different synchronization patterns comprise at least two of: initial acquisition in standalone mode, initial acquisition in non-standalone mode, synchronization in idle mode, synchronization provided to another base station in backhaul network or connected mode.

5. The method of claim 1, wherein the indication is provided via at least one of: a synchronization signal, a Master Information Block (MIB), or a demodulation reference signal (DMRS).

6. The method of claim 1, wherein:

the indication is provided via at least one of a redundancy version or a scrambling sequence of the PBCH transmission; and

different values of the first set of bits are mapped to different redundancy versions.

7. The method of claim 1, wherein the indication is provided via at least two of:

a mapping of different values of the first set of synchronization signals, a Master Information Block (MIB), a demodulation reference signal (DMRS), a scrambling sequence, or bits to different redundancy versions of the PBCH.

8. The method of claim 7, wherein both the DMRS and the scrambling sequence carry a portion of a Synchronization Signal Block (SSB) index.

9. The method of claim 7, wherein:

for a first set of PBCH TTIs, the design of the DMRS and the scrambling sequence is the same for each PBCH TTI; and

for a second set of PBCH TTIs, the design of the DMRS and the scrambling sequence is PBCH TTI dependent.

10. The method of claim 7, wherein both the DMRS and the MIB carry part of an indication of a field.

11. The method of claim 1, further comprising: transmitting information regarding the PBCH period and/or TTI duration to a wireless device.

12. The method of claim 11, wherein the information is communicated via at least one of: master Information Block (MIB), System Information Block (SIB), or Radio Resource Control (RRC) signaling.

13. The method of claim 11, wherein:

the information is transmitted via a first Radio Access Technology (RAT) network; and

the PBCH is transmitted via a second RAT network.

14. A method for wireless communications by a wireless device, comprising:

determining a first set of one or more bits in a timing reference number that change over a duration of a Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI;

decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein the plurality of versions comprise a second set of bits of the timing reference number that do not change for the duration of the TTI; and

obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

15. The method of claim 14, wherein the timing reference number comprises at least one of: a System Frame Number (SFN), an indication of subframe level, an indication of symbol level timing, a Synchronization Signal Block (SSB) index, or an indication of a field.

16. The method of claim 14, wherein different synchronization patterns have different durations of the TTI.

17. The method of claim 16, wherein different synchronization patterns comprise at least two of: initial acquisition in standalone mode, initial acquisition in non-standalone mode, synchronization in idle mode, synchronization provided to another base station in backhaul network or connected mode.

18. The method of claim 14, wherein the indication is provided via at least one of: a synchronization signal, a Master Information Block (MIB), or a demodulation reference signal (DMRS).

19. The method of claim 14, wherein:

the indication is provided via at least one of a redundancy version or a scrambling sequence of the PBCH transmission; and

different values of the first set of bits are mapped to different redundancy versions.

20. The method of claim 14, wherein the indication is provided via at least two of:

a mapping of different values of the first set of synchronization signals, a Master Information Block (MIB), a demodulation reference signal (DMRS), a scrambling sequence, or bits to different redundancy versions of the PBCH.

21. The method of claim 20, wherein both the DMRS and the scrambling sequence carry a portion of a Synchronization Signal Block (SSB) index.

22. The method of claim 20, wherein:

for a first set of PBCH TTIs, the design of the DMRS and the scrambling sequence is the same for each PBCH TTI; and

for a second set of PBCH TTIs, the design of the DMRS and the scrambling sequence is PBCH TTI dependent.

23. The method of claim 20, wherein both the DMRS and the MIB carry a portion of an indication of a field.

24. The method of claim 14, further comprising: obtaining information regarding the PBCH period and/or TTI duration from another wireless device.

25. The method of claim 24, wherein the information is obtained via at least one of: master Information Block (MIB), System Information Block (SIB), or Radio Resource Control (RRC) signaling.

26. The method of claim 24, wherein:

the information is obtained from a first base station; and

the PBCH is transmitted by a second base station.

27. The method of claim 24, wherein:

the information is obtained via a first Radio Access Technology (RAT) network; and

the PBCH is transmitted via a second RAT network.

28. The method of claim 14, further comprising:

deriving, at least in part, information regarding the periodicity of the PBCH TTI by detection of multiple instances of a demodulation reference Signal (DMRS); and

subsequent PBCH processing is performed using the derived information.

29. An apparatus for wireless communications by a base station, comprising:

means for determining a first set of one or more bits of a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI;

means for transmitting, within the TTI, a plurality of versions of a Physical Broadcast Channel (PBCH) that includes a second set of bits of the timing reference number that do not change for the duration of the TTI; and

means for providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

30. An apparatus for wireless communications by a wireless device, comprising:

means for determining a first set of one or more bits in a timing reference number that change over a duration of a Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI;

means for decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein the plurality of versions comprise a second set of bits of the timing reference number that do not change for the duration of the TTI; and

means for obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

31. An apparatus for wireless communications by a base station, comprising:

at least one processor coupled with the memory and configured to: determining a first set of one or more bits in a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; and

a transceiver configured to: transmitting a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, the plurality of versions comprising a second set of bits of the timing reference number that do not change for the duration of the TTI; and providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

32. An apparatus for wireless communications by a wireless device, comprising:

at least one processor coupled with the memory and configured to: determining a first set of one or more bits in a timing reference number that change over a duration of a Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; and

a decoder configured to: decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein the plurality of versions comprise a second set of bits of the timing reference number that do not change for the duration of the TTI; and obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

Technical Field

The present disclosure relates generally to wireless communication systems, and more particularly to methods and apparatus for transmitting timing information.

Background

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasting. Typical wireless communication systems may employ multiple-access techniques capable of supporting communication with multiple users by sharing the available system resources (e.g., bandwidth, transmit power). Examples of such multiple-access techniques include Long Term Evolution (LTE) systems, Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems.

In some examples, a wireless multiple-access communication system may include multiple base stations, each supporting communication for multiple communication devices (otherwise referred to as User Equipment (UE)) simultaneously. In an LTE or LTE-a network, a set of one or more base stations may define an evolved node b (enb). In other examples (e.g., in a next generation or 5 th generation (5G) network), a wireless multiple-access communication system may include a plurality of Distributed Units (DUs) (e.g., Edge Units (EUs), Edge Nodes (ENs), Radio Heads (RHs), intelligent radio heads (SRHs), Transmission Reception Points (TRPs), etc.) in communication with a plurality of Central Units (CUs) (e.g., Central Nodes (CNs), Access Node Controllers (ANCs), etc.), wherein a set of one or more distributed units in communication with a central unit may define an access node (e.g., a new radio base station (NR BS), a new radio node b (NR NB), a network node, a 5G NB, an eNB, etc.). A base station or DU may communicate with a set of UEs on downlink channels (e.g., for transmissions from the base station to the UEs) and uplink channels (e.g., for transmissions from the UEs to the base station or distributed units).

These multiple access techniques have been employed in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate on a city, country, region, and even global level. An example of an emerging telecommunications standard is New Radio (NR), e.g., 5G radio access. NR generally refers to an enhanced set of LTE mobile standards promulgated by the third generation partnership project (3 GPP). It is designed to better integrate with other open standards by improving spectral efficiency, reducing costs, improving services, utilizing new spectrum, and using OFDMA with Cyclic Prefix (CP) on Downlink (DL) and on Uplink (UL), thereby better supporting mobile broadband internet access, as well as supporting beamforming, Multiple Input Multiple Output (MIMO) antenna technology, and carrier aggregation.

However, as the demand for mobile broadband access continues to grow, there is a desire for further improvements in NR technology. Preferably, these improvements should be applicable to other multiple access techniques and telecommunications standards employing these techniques.

Disclosure of Invention

The systems, methods, and devices of the present disclosure each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of the present disclosure as expressed by the claims that follow, some features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled "detailed description" one will understand how the features of this disclosure provide advantages that include improved communication between access points and stations in a wireless network.

Certain aspects provide techniques for communicating timing indications through a demodulation reference signal (DMRS) and a Physical Broadcast Channel (PBCH) in different modes, as described herein.

Certain aspects provide a method for wireless communications by a Base Station (BS). In summary, the method comprises: determining a first set of one or more bits in a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; transmitting multiple versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein each version of the PBCH has identical content comprising a second set of bits of the timing reference number that do not change for the duration of the TTI; and providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

Certain aspects provide a method for wireless communications by a User Equipment (UE). In summary, the method comprises: determining a first set of one or more bits in a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein each version of the PBCH has identical content comprising a second set of bits of the timing reference number that do not change for the duration of the TTI; and obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

Certain aspects provide an apparatus for wireless communications by a Base Station (BS). In summary, the apparatus comprises: means for determining a first set of one or more bits of a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; means for transmitting, within the TTI, a plurality of versions of a Physical Broadcast Channel (PBCH) that includes a second set of bits of the timing reference number that do not change for the duration of the TTI; and means for providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

Certain aspects provide an apparatus for wireless communications by a wireless device. In summary, the apparatus comprises: means for determining a first set of one or more bits in a timing reference number that change over a duration of a Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; means for decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein the plurality of versions comprise a second set of bits of the timing reference number that do not change for the duration of the TTI; and means for obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

Certain aspects provide an apparatus for wireless communications by a wireless device. In summary, the apparatus comprises: at least one processor coupled with the memory and configured to: determining a first set of one or more bits in a timing reference number transmitted in a Physical Broadcast Channel (PBCH) that change over a duration of a PBCH Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; and a transceiver configured to: transmitting a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, the plurality of versions comprising a second set of bits of the timing reference number that do not change for the duration of the TTI; and providing an indication of the first set of bits in the timing reference number with each PBCH transmission.

Certain aspects provide an apparatus for wireless communications by a wireless device. In summary, the apparatus comprises: at least one processor coupled with the memory and configured to: determining a first set of one or more bits in a timing reference number that change over a duration of a Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) based on a PBCH transmission period and the duration of the TTI; and a decoder configured to: decoding at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, wherein the plurality of versions comprise a second set of bits of the timing reference number that do not change for the duration of the TTI; and obtaining an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

Aspects generally include methods, apparatus, systems, computer-readable media, and processing systems substantially as described herein with reference to and as illustrated by the accompanying drawings.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed and the description is intended to include all such aspects and their equivalents.

Drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects.

Fig. 1 is a block diagram conceptually illustrating an example telecommunications system in accordance with certain aspects of the present disclosure.

Fig. 2 is a block diagram illustrating an example logical architecture of a distributed RAN in accordance with certain aspects of the present disclosure.

Fig. 3 is a diagram illustrating an example physical architecture of a distributed RAN in accordance with certain aspects of the present disclosure.

Fig. 4 is a block diagram conceptually illustrating a design of an example BS and User Equipment (UE), in accordance with certain aspects of the present disclosure.

Fig. 5 is a diagram illustrating an example for implementing a communication protocol stack in accordance with certain aspects of the present disclosure.

Fig. 6 illustrates an example of a downlink-centric (DL-centric) subframe in accordance with certain aspects of the present disclosure.

Fig. 6A illustrates an example of an uplink-centric (UL-centric) subframe in accordance with certain aspects of the present disclosure.

Fig. 7 illustrates an example Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) and transmission period.

Fig. 8 illustrates an example transmission timeline for a synchronization signal for a new radio telecommunication system, in accordance with aspects of the present disclosure.

Fig. 9 illustrates an example resource mapping for an example Synchronization Signal (SS) block (SSB), in accordance with aspects of the present disclosure.

Fig. 10 illustrates example operations for wireless communications by a base station in accordance with certain aspects of the present disclosure.

Fig. 11 illustrates example operations for wireless communications by a User Equipment (UE) in accordance with certain aspects of the present disclosure.

Fig. 12 shows another example Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) and transmission period.

Fig. 13 shows how timing information for the configuration of fig. 12 may be communicated.

Figure 14 shows yet another example Physical Broadcast Channel (PBCH) Transmission Time Interval (TTI) and transmission period.

Fig. 15 shows how timing information for the configuration of fig. 14 may be communicated.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized on other aspects without specific recitation.

Detailed Description

Aspects of the present disclosure relate to methods and apparatus for communicating timing information that may change, for example, within a transmission time interval within which a redundancy version of a PBCH is transmitted.

Aspects of the present disclosure provide apparatuses, methods, processing systems, and computer-readable media for a New Radio (NR) (new radio access technology or 5G technology).

NR may support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidths (e.g., over 80MHz), millimeter wave (mmW) targeting high carrier frequencies (e.g., 60GHz), massive MTC (MTC) targeting non-backward compatible MTC technologies, and/or mission critical targeting ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different Transmission Time Intervals (TTIs) to meet corresponding quality of service (QoS) requirements. In addition, these services may coexist in the same subframe.

The following description provides examples, but does not limit the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For example, the described methods may be performed in an order different than that described, and various steps may be added, omitted, or combined. Furthermore, features described with respect to some examples may be combined into some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. Moreover, the scope of the present disclosure is intended to cover such an apparatus or method implemented with other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. The word "exemplary" is used herein to mean "serving as an example, instance, or illustration. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects.

The techniques described herein may be used for various wireless communication networks, such as LTE, CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and others. The terms "network" and "system" are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), CDMA2000, etc. UTRA includes wideband CDMA (wcdma) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. TDMA networks may implement radio technologies such as global system for mobile communications (GSM). An OFDMA network may implement radio technologies such as NR (e.g., 5G RA), evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11(Wi-Fi), IEEE 802.16(WiMAX), IEEE802.20, flash-OFDM, etc. UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). NR is an emerging wireless communication technology under development that incorporates the 5G technology forum (5 GTF). 3GPP Long Term Evolution (LTE) and LTE-advanced (LTE-A) are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE-A, 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 wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. For clarity, although aspects may be described herein using terms commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure may be applied to other generation-based communication systems (e.g., 5G and beyond technologies, including NR technologies).

Example Wireless communication System

Fig. 1 illustrates an example wireless network 100, e.g., a New Radio (NR) or 5G network, in which aspects of the disclosure may be performed.

As shown in fig. 1, wireless network 100 may include multiple BSs 110 and other network entities. The BS may be a station communicating with the UE. Each BS 110 may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to a coverage area of a node B and/or a node B subsystem serving that coverage area, depending on the context in which the term is used. In an NR system, the term "cell" and eNB, node B, 5G NB, AP, NR BS or TRP may be interchanged. In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of the mobile base station. In some examples, the base stations may be interconnected with each other and/or with one or more other base stations or network nodes (not shown) in wireless network 100 by various types of backhaul interfaces (e.g., interfaces that are directly physically connected, virtual networks, or use any suitable transport networks).

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular Radio Access Technology (RAT) and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, air interface, etc. The frequencies may also be referred to as carriers, frequency channels, etc. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks having different RATs. In some cases, NR or 5G RAT networks may be deployed.

The BS may provide communication coverage for a macrocell, picocell, femtocell, and/or other type of cell. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a residence) and may allow 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 residence, etc.). The BS for the macro cell may be referred to as a macro BS. The BS for the pico cell may be referred to as a pico BS. The BS for the femto cell may be referred to as a femto BS or a home BS. In the example shown in fig. 1, BSs 110a, 110b, and 110c may be macro BSs for macro cells 102a, 102b, and 102c, respectively. BS 110x may be a pico BS for pico cell 102 x. BSs 110y and 110z may be femto BSs for femtocells 102y and 102z, respectively. A BS may support one or more (e.g., three) cells.

Wireless network 100 may also include relay stations. A relay station is a station that receives data transmissions and/or other information from an upstream station (e.g., a BS or a UE) and transmits data transmissions and/or other information to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that relays transmissions for other UEs. In the example shown in fig. 1, relay 110r may communicate with BS 110a and UE120r to facilitate communication between BS 110a and UE120 r. The relay station may also be referred to as a relay BS, a relay, etc.

The wireless network 100 may be a heterogeneous network including different types of BSs (e.g., macro BSs, pico BSs, femto BSs, repeaters, etc.). These different types of BSs may have different transmit power levels, different coverage areas, and different effects on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 20 watts), while pico BSs, femto BSs, and repeaters may have a lower transmit power level (e.g., 1 watt).

Wireless network 100 may support synchronous or asynchronous operation. For synchronous operation, BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timings, and transmissions from different BSs may not be aligned in time. The techniques described herein may be used for both synchronous and asynchronous operations.

Network controller 130 may couple to a set of BSs and provide coordination and control for these BSs. Network controller 130 may communicate with BS 110 via a backhaul. BSs 110 may also communicate with each other, either directly or indirectly, e.g., via a wireless or wired backhaul.

UEs 120 (e.g., 120x, 120y, etc.) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as a mobile station, a terminal, an access terminal, a subscriber unit, a station, a Customer Premises Equipment (CPE), a cellular telephone, a smartphone, a Personal Digital Assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop, a cordless telephone, a Wireless Local Loop (WLL) station, a tablet device, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or medical apparatus, a biometric sensor/device, a wearable device (e.g., a smartwatch, a smart garment, smart glasses, a smart wristband, smart jewelry (e.g., a smart ring, a smart bracelet, etc.)), an entertainment device (e.g., a music device, a video device, a satellite radio, etc.), a vehicle component or sensor, a smart meter/sensor, an industrial manufacturing device, a global positioning system device, a satellite radio, etc, Or any other suitable device configured to communicate via a wireless or wired medium. Some UEs may be considered evolved or Machine Type Communication (MTC) devices or evolved MTC (emtc) devices. MTC and eMTC UEs include, for example, a robot, a drone, a remote device, a sensor, a meter, a monitor, a location tag, etc., which may communicate with a BS, another device (e.g., a remote device), or some other entity. The wireless nodes may provide connectivity, for example, to or from a network (e.g., a wide area network such as the internet or a cellular network) via wired or wireless communication links. Some UEs may be considered internet of things (IoT) devices. In fig. 1, a solid line with double arrows indicates desired transmissions between a UE and a serving BS, which is a BS designated to serve the UE on the downlink and/or uplink. The dashed line with double arrows indicates interfering transmissions between the UE and the BS.

Some wireless networks (e.g., LTE) utilize Orthogonal Frequency Division Multiplexing (OFDM) on the downlink and single carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, and so on. Each subcarrier may be modulated with data. Typically, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may depend on the system bandwidth. For example, the spacing of the subcarriers may be 15kHz and the minimum resource allocation (referred to as a "resource block") may be 12 subcarriers (or 180 kHz). Thus, for a system bandwidth of 1.25, 2.5, 5,10, or 20 megahertz (MHz), the nominal FFT size may be equal to 128, 256, 512, 1024, or 2048, respectively. The system bandwidth may also be divided into subbands. For example, a sub-band may cover 1.08MHz (i.e., 6 resource blocks), and there may be 1, 2, 4, 8, or 16 sub-bands for a system bandwidth of 1.25, 2.5, 5,10, or 20MHz, respectively.

Although aspects of the examples described herein may be associated with LTE technology, aspects of the disclosure may be applied with other wireless communication systems (e.g., NRs). NR may utilize OFDM with CP on the uplink and downlink, and may include support for half-duplex operation using Time Division Duplex (TDD). A single component carrier bandwidth of 100MHz may be supported. The NR resource block may span 12 subcarriers having a subcarrier bandwidth of 75kHz in 0.1ms duration. Each radio frame may consist of 50 subframes, having a length of 10 ms. Thus, each subframe may have a length of 0.2 ms. Each subframe may indicate a link direction (i.e., DL or UL) for data transmission, and the link direction for each subframe may be dynamically switched. Each subframe may include DL/UL data as well as DL/UL control data. The UL and DL subframes for NR may be described in more detail below with respect to fig. 6 and 7. Beamforming may be supported and beam directions may be dynamically configured. MIMO transmission with precoding may also be supported. A MIMO configuration in the DL may support up to 8 transmit antennas, with a multi-layer DL transmitting up to 8 streams and up to 2 streams per UE. Multi-layer transmission with up to 2 streams per UE may be supported. Aggregation of multiple cells with up to 8 serving cells may be supported. Alternatively, the NR may support a different air interface than the OFDM-based air interface. The NR network may comprise entities such as CUs and/or DUs.

In some examples, access to the air interface may be scheduled, where a scheduling entity (e.g., a base station) allocates resources for communication among some or all of the devices and apparatuses within its service area or cell. Within this disclosure, the scheduling entity may be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more subordinate entities, as discussed further below. That is, for scheduled communications, the subordinate entity utilizes the resources allocated by the scheduling entity. The base station is not the only entity that can be used as a scheduling entity. That is, in some examples, a UE may serve as a scheduling entity that schedules resources for one or more subordinate entities (e.g., one or more other UEs). In this example, the UE is acting as a scheduling entity, while other UEs utilize the resources scheduled by the UE for wireless communication. The UE may serve as a scheduling entity in a peer-to-peer (P2P) network and/or in a mesh network. In the mesh network example, in addition to communicating with the scheduling entity, the UEs may optionally communicate directly with each other.

Thus, in a wireless communication network having scheduled access to time-frequency resources and having a cellular configuration, a P2P configuration, and a mesh configuration, a scheduling entity and one or more subordinate entities may communicate utilizing the scheduled resources.

As mentioned above, the RAN may include CUs and DUs. An NR BS (e.g., eNB, 5G node B, transmission reception point (TPR), Access Point (AP)) may correspond to one or more BSs. The NR cell may be configured as an access cell (ACell) or a data cell only (DCell). For example, a RAN (e.g., a central unit or a distributed unit) may configure a cell. The DCell may be a cell for carrier aggregation or dual connectivity, but not for initial access, cell selection/reselection, or handover. In some cases, the DCell may not transmit synchronization signals — in some cases, the DCell may transmit SSs. The NRBS may transmit a downlink signal indicating a cell type to the UE. Based on the cell type indication, the UE may communicate with the NR BS. For example, the UE may determine the NR BSs to consider for cell selection, access, handover, and/or measurement based on the indicated cell type.

Fig. 2 illustrates an example logical architecture of a distributed Radio Access Network (RAN)200 that may be implemented in the wireless communication system shown in fig. 1. The 5G access node 206 may include an Access Node Controller (ANC) 202. ANC may be a Central Unit (CU) of the distributed RAN 200. The backhaul interface to the next generation core network (NG-CN)204 may terminate at the ANC. The backhaul interface to the neighboring next generation access node (NG-AN) may terminate at the ANC. An ANC may include one or more TRPs 208 (which may also be referred to as a BS, NR BS, node B, 5G NB, AP, or some other terminology). As described above, TRP may be used interchangeably with "cell".

TRP208 may be a DU. A TRP may be attached to one ANC (ANC 202) or more than one ANC (not shown). For example, for RAN sharing, radio as a service (RaaS), AND service-specific AND deployments, a TRP may be connected to more than one ANC. The TRP may include one or more antenna ports. The TRP may be configured to provide services to the UE either individually (e.g., dynamic selection) or jointly (e.g., joint transmission).

The local architecture 200 may be used to illustrate the fronthaul definition. The architecture may be defined to support a fronthaul scheme across different deployment types. For example, the architecture may be based on the transmitting network capabilities (e.g., bandwidth, latency, and/or jitter).

The architecture may share features and/or components with LTE. According to aspects, the next generation AN (NG-AN)210 may support dual connectivity with NRs. The NG-ANs may share a common fronthaul for LTE and NR.

The architecture may enable cooperation between and among TRPs 208. For example, cooperation may be pre-configured within and/or across the TRP via the ANC 202. According to aspects, no inter-TRP interface may be required/present.

According to aspects, there may be a dynamic configuration of split logic functionality in the architecture 200. As will be described in more detail with reference to fig. 5, a Radio Resource Control (RRC) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Link Control (RLC) layer, a Medium Access Control (MAC) layer, and a Physical (PHY) layer may be adaptively placed at a DU or a CU (e.g., TRP or ANC, respectively). According to certain aspects, a BS may include a Central Unit (CU) (e.g., ANC 202) and/or one or more distributed units (e.g., one or more TRPs 208).

Fig. 3 illustrates an example physical architecture of a distributed RAN 300, in accordance with aspects of the present disclosure. A centralized core network unit (C-CU)302 may host core network functions. The C-CU may be deployed centrally. The C-CU functions may be offloaded (e.g., to Advanced Wireless Services (AWS)) to handle peak capacity.

A centralized RAN unit (C-RU)304 may host one or more ANC functions. Alternatively, the C-RU may locally host the core network functions. The C-RU may have a distributed deployment. The C-RU may be closer to the network edge.

DU 306 may host one or more TRPs (edge node (EN), Edge Unit (EU), Radio Head (RH), Smart Radio Head (SRH), etc.). The DU may be located at the edge of a Radio Frequency (RF) enabled network.

Fig. 4 illustrates example components of BS 110 and UE120 shown in fig. 1 that may be used to implement aspects of the present disclosure. As described above, the BS may include TRP. One or more components in BS 110 and UE120 may be used to implement aspects of the present disclosure. For example, antennas 452, Tx/Rx 222, processors 466, 458, 464, and/or controller/processor 480 of UE120, and/or antennas 434, processors 460, 420, 438, and/or controller/processor 440 of BS 110 may be used to perform the operations described herein and shown with reference to fig. 8-11.

Fig. 4 shows a block diagram of a design of BS 110 and UE120 (which may be one of the BSs and one of the UEs in fig. 1). For the restricted association scenario, base station 110 may be macro BS 110c in fig. 1, and UE120 may be UE120 y. The base station 110 may also be some other type of base station. Base station 110 may be equipped with antennas 434a through 434t, and UE120 may be equipped with antennas 452a through 452 r.

At base station 110, a transmit processor 420 may receive data from a data source 412 and control information from a controller/processor 440. The control information may be for a Physical Broadcast Channel (PBCH), a Physical Control Format Indicator Channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a Physical Downlink Control Channel (PDCCH), etc. The data may be for a Physical Downlink Shared Channel (PDSCH), etc. Processor 420 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. Processor 420 may also generate reference symbols, e.g., for PSS, SSS, and cell-specific reference signals. A Transmit (TX) multiple-input multiple-output (MIMO) processor 430 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to Modulators (MODs) 432a through 432 t. For example, TX MIMO processor 430 may perform certain aspects described herein for RS multiplexing. Each modulator 432 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 432 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from modulators 432a through 432t may be transmitted via antennas 434a through 434t, respectively.

At UE120, antennas 452a through 452r may receive downlink signals from base station 110 and may provide received signals to demodulators (DEMODs) 454a through 454r, respectively. Each demodulator 454 may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator 454 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 456 may obtain received symbols from all demodulators 454a through 454r, perform MIMO detection on the received symbols (if applicable), and provide detected symbols. For example, MIMO detector 456 provides detected RSs that are transmitted using the techniques described herein. A receive processor 458 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE120 to a data sink 460, and provide decoded control information to a controller/processor 480. According to one or more scenarios, the CoMP aspects may include providing antennas and some Tx/Rx functionality such that they are located in a distributed unit. For example, some Tx/Rx processing may be done in a central unit, while other processing may be done at distributed units. For example, BS modulator/demodulator 432 may be in a distributed unit in accordance with one or more aspects as illustrated in the figures.

On the uplink, at UE120, a transmit processor 464 may receive and process data from a data source 462 (e.g., for a Physical Uplink Shared Channel (PUSCH)) and control information from a controller/processor 480 (e.g., for a Physical Uplink Control Channel (PUCCH)). The transmit processor 464 may also generate reference symbols for a reference signal. The symbols from transmit processor 464 may be precoded by a TX MIMO processor 466 if applicable, further processed by demodulators 454a through 454r (e.g., for SC-FDM, etc.), and transmitted to base station 110. At BS 110, the uplink signals from UE120 may be received by antennas 434, processed by modulators 432, detected by a MIMO detector 436 (if applicable), and further processed by a receive processor 438 to obtain decoded data and control information sent by UE 120. A receive processor 438 may provide decoded data to a data sink 439 and decoded control information to a controller/processor 440.

Controllers/processors 440 and 480 may direct the operation at base station 110 and UE120, respectively. Processor 440 and/or other processors and modules at base station 110 may perform or direct the execution of functional blocks such as those shown in fig. 8-11 and/or other processes for the techniques described herein. Processor 480 and/or other processors and modules at UE120 may also perform or direct processes for the techniques described herein. Memories 442 and 482 may store data and program codes for BS 110 and UE120, respectively. A scheduler 444 may schedule UEs for data transmission on the downlink and/or uplink.

Fig. 5 shows a diagram 500 depicting an example for implementing a communication protocol stack, in accordance with aspects of the present disclosure. The illustrated communication protocol stack may be implemented by a device operating in a 5G system (e.g., a system supporting uplink-based mobility). Diagram 500 shows a communication protocol stack that includes a Radio Resource Control (RRC) layer 510, a Packet Data Convergence Protocol (PDCP) layer 515, a Radio Link Control (RLC) layer 520, a Medium Access Control (MAC) layer 525, and a Physical (PHY) layer 530. In various examples, the layers of the protocol stack may be implemented as separate software modules, portions of a processor or ASIC, portions of non-co-located devices connected by a communications link, or various combinations thereof. The collocated and non-collocated implementations may be used, for example, in a protocol stack for a network access device (e.g., AN, CU, and/or DU) or UE.

A first option 505-a illustrates a split implementation of a protocol stack, where the implementation of the protocol stack is split between a centralized network access device (e.g., ANC 202 in fig. 2) and a distributed network access device (e.g., DU 208 in fig. 2). In the first option 505-a, the RRC layer 510 and the PDCP layer 515 may be implemented by a central unit, while the RLC layer 520, the MAC layer 525 and the physical layer 530 may be implemented by DUs. In various examples, a CU and a DU may be co-located or non-co-located. The first option 505-a may be useful in a macrocell, microcell, or picocell deployment.

A second option 505-b illustrates a unified implementation of a protocol stack, wherein the protocol stack is implemented in a single network access device (e.g., Access Node (AN), new radio base station (NR BS), new radio node b (nrnb), Network Node (NN), etc.). In a second option, the RRC layer 510, PDCP layer 515, RLC layer 520, MAC layer 525, and physical layer 530 may all be implemented by AN. The second option 505-b may be useful in femtocell deployments.

Regardless of whether the network access device implements part or all of the protocol stack, the UE may implement the entire protocol stack (e.g., RRC layer 510, PDCP layer 515, RLC layer 520, MAC layer 525, and physical layer 530).

Fig. 6 is a diagram 600 illustrating an example of a DL-centric subframe. The DL-centric subframe may include a control portion 602. The control portion 602 may exist at an initial or beginning portion of a subframe centered on the DL. The control portion 602 may include various scheduling information and/or control information corresponding to various portions of a DL-centric subframe. In some configurations, the control portion 602 may be a Physical DL Control Channel (PDCCH), as indicated in fig. 6. The DL centric sub-frame may also include a DL data portion 604. The DL data portion 604 may sometimes be referred to as the payload of a DL-centric subframe. The DL data portion 604 may include communication resources for transmitting DL data from a scheduling entity (e.g., a UE or BS) to a subordinate entity (e.g., a UE). In some configurations, the DL data portion 604 may be a Physical DL Shared Channel (PDSCH).

The DL-centric sub-frame may also include a common UL portion 606. Common UL portion 606 may sometimes be referred to as an UL burst, a common UL burst, and/or various other suitable terms. The common UL portion 606 may include feedback information corresponding to various other portions of the DL-centric sub-frame. For example, the common UL portion 606 may include feedback information corresponding to the control portion 602. Non-limiting examples of feedback information may include ACK signals, NACK signals, HARQ indicators, and/or various other suitable types of information. The common UL portion 606 may include additional or alternative information, such as information related to Random Access Channel (RACH) procedures, Scheduling Requests (SRs), and various other suitable types of information. As shown in fig. 6, the end of the DL data portion 604 may be separated in time from the beginning of the common UL portion 606. Such temporal separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. This separation provides time for switching from DL communications (e.g., receive operations by a subordinate entity (e.g., a UE)) to UL communications (e.g., transmissions by a subordinate entity (e.g., a UE)). Those skilled in the art will appreciate that the foregoing is merely one example of a DL-centric subframe and that alternative structures with similar features may exist without necessarily departing from aspects described herein.

Fig. 6A is a diagram 650 illustrating an example of a UL-centric subframe. The UL-centric sub-frame may include a control portion 652. Control portion 652 may reside in an initial or beginning portion of a UL-centric subframe. The control portion 652 in fig. 6A may be similar to the control portion described above with reference to fig. 6. The UL-centric sub-frame may also include an UL data portion 654. UL data portion 654 may sometimes be referred to as the payload of a UL-centric subframe. The UL data portion may refer to a communication resource for transmitting UL data from a subordinate entity (e.g., a UE) to a scheduling entity (e.g., a UE or a BS). In some configurations, control portion 652 may be a Physical DL Control Channel (PDCCH).

As shown in fig. 6A, the end of control portion 652 may be separated in time from the beginning of UL data portion 654. Such temporal separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. This separation provides time for switching from DL communications (e.g., receive operations by the scheduling entity) to UL communications (e.g., transmissions by the scheduling entity). The UL-centric sub-frame may also include a common UL portion 656. The common UL portion 656 in fig. 6A may be similar to the common UL portion 656 described above with reference to fig. 6A. Common UL portion 656 may additionally or alternatively include Channel Quality Indicators (CQIs), Sounding Reference Signals (SRS), and various other suitable types of information. Those skilled in the art will appreciate that the foregoing is merely one example of a UL-centric subframe and that alternative structures having similar features may exist without necessarily departing from aspects described herein.

In some cases, two or more subordinate entities (e.g., UEs) may communicate with each other using sidelink signals. Real-life applications of such sidelink communications may include public safety, proximity services, UE-to-network relays, vehicle-to-vehicle (V2V) communications, internet of everything (IoE) communications, IoT communications, mission critical meshes, and/or various other suitable applications. In general, sidelink signals may refer to signals transmitted from one subordinate entity (e.g., UE1) to another subordinate entity (e.g., UE2) without the need to relay the communication through a scheduling entity (e.g., UE or BS), even though the scheduling entity may be used for scheduling and/or control purposes. In some examples, the sidelink signals may be transmitted using licensed spectrum (as opposed to wireless local area networks that typically use unlicensed spectrum).

The UE may operate in various radio resource configurations including configurations associated with transmitting pilots using a set of dedicated resources (e.g., Radio Resource Control (RRC) dedicated state, etc.), or configurations associated with transmitting pilots using a set of common resources (e.g., RRC common state, etc.). When operating in the RRC dedicated state, the UE may select a dedicated set of resources for transmitting pilot signals to the network. When operating in the RRC common state, the UE may select a common set of resources for transmitting pilot signals to the network. In either case, the pilot signal transmitted by the UE may be received by one or more network access devices (e.g., AN or DU or portions thereof). Each receiving network access device may be configured to receive and measure pilot signals transmitted on a common set of resources, and also receive and measure pilot signals transmitted on a set of dedicated resources allocated to UEs for which the network access device is a member of the set of network access devices monitoring for the UE. CUs receiving one or more of the network access devices, or receiving measurements to which the network access devices send pilot signals, may use the measurements to identify serving cells for the UEs, or initiate changes to serving cells for one or more of the UEs.

Example PBCH TTI

In some cases, control information may be "bundled" into multiple transmissions within a time period referred to as a Transmission Time Interval (TTI). For example, different "redundancy" versions of the same information may be sent periodically within a TTI, allowing a receiver to combine multiple instances of information for better decoding performance.

For example, as shown in fig. 7, in LTE, PBCH may be transmitted with a periodicity of 10msec within a 40msec BCH TTI. Each instance 702 of PBCH within BCH TTI is one RV (redundancy version) of the coded block (RV0, RV1, RV2, RV 3). The UE may combine multiple instances 702 of the PBCH within the BCH TTI before decoding for better performance. However, the UE needs to blindly decode the redundancy versions to perform the combining, since the encoded information in the subsequent instance 704 of the PBCH may change in the next TTI.

MIB (master information block) is transmitted through PBCH. The MIB carries SFN (system frame number) bits as timing reference. The MIB carries all SFN bits except the two LSBs (least significant bits). The two LSBs may be obtained by the UE through PBCH decoding.

In other words, since four 10msec frames fit within a 40msec TTI, only these 2 LSBs of the SFN will change within the TTI. Thus, other bits may be included in different redundancy versions while maintaining the same content, which allows for combining.

In some cases, a first radio frame structure (referred to as type 1) is for FDD (for both full-duplex and half-duplex operation) and has a duration of 10ms and comprises 20 slots, with a slot duration of 0.5 ms. In this case, two adjacent slots form one subframe having a length of 1 ms. A second radio frame structure (referred to as type 2) is used for TDD and is formed of two half-frames each having a duration of 5 ms. Each half-frame includes 10 slots of length 0.5ms, or 8 slots of length 0.5ms and three special fields (DwPTS, GP and UpPTS) of configurable individual length and total length 1ms, supporting both 5ms and 10ms downlink to uplink switch point periods.

Example synchronization Signal Block design

According to the 5G wireless communication standard of 3GPP, a structure has been defined for NR synchronization (synch) signals (NR-SS), also referred to as NR synchronization channels. According to 5G, a set of consecutive OFDM symbols carrying different types of synchronization signals (e.g., Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Time Synchronization Signal (TSS), and PBCH) form an SS block. In some cases, a set of one or more SS blocks may form an SS burst. In addition, different SS blocks may be transmitted on different beams to enable beam scanning for synchronization signals, which may be used by the UE to quickly identify and acquire cells. Further, one or more of the channels in the SS block may be used for measurements. Such measurements may be used for various purposes, e.g., Radio Link Measurements (RLM), beam management, and so on. For example, the UE may measure the cell quality and report back the quality in the form of a measurement report, which may be used by the base station for beam management and other purposes.

Fig. 8 shows an example transmission timeline 800 for a synchronization signal for a new radio telecommunication system, in accordance with aspects of the present disclosure. In accordance with certain aspects of the present disclosure, a BS (e.g., BS 110 shown in fig. 1) may transmit SS burst 802 during period 806 having Y μ sec. SS burst 802 may include N SS blocks 804 with indices of zero to N-1, and the BS may transmit different SS blocks of the burst using different transmit beams (e.g., for beam scanning). As mentioned above, each SS block may include, for example, PSS, SSs, and one or more PBCH. The BS may periodically transmit SS bursts with a period 808 of X msec.

Fig. 9 illustrates an example resource mapping 900 for an example SS block 902, in accordance with aspects of the present disclosure. An exemplary SS block includes a PSS 910, a SSs 912, and two PBCHs 920 and 922, but the disclosure is not limited thereto, and an SS block may include more or less synchronization signals and synchronization channels. As shown, the transmission bandwidth of the PBCH (B1) may be different from the transmission bandwidth of the synchronization signal (B2). For example, the transmission bandwidth of PBCH may be 288 tones, while the transmission bandwidth of PSS and SSS may be 127 tones. As shown in fig. 9, PSS, SSs, and PBCH within an SS block (and DMRS for PBCH) are multiplexed in the time domain.

There are different synchronization modes: initial acquisition in standalone mode, initial acquisition in non-standalone mode, and synchronization in idle or connected mode. As will be described herein, these different synchronization patterns may have different PBCH TTIs and PBCH transmission periods. Thus, different SFN bits can change within a TTI, posing a challenge to keep the same content in each redundancy version.

Example timing indication through MIB

Certain aspects of the present disclosure relate to methods and apparatus for communicating timing information that varies across Transmission Time Intervals (TTIs) in which multiple redundancy versions of a Physical Broadcast Channel (PBCH) are transmitted.

Fig. 10 illustrates example operations 1000 for transmitting timing information by a Base Station (BS) (e.g., BS 110 shown in fig. 1) (or some other type of network entity), in accordance with aspects of the present disclosure.

At 1002, the operations 1000 begin by: a first set of one or more bits in a timing reference number transmitted in a PBCH that change over a duration of a Transmission Time Interval (TTI) is determined based on a Physical Broadcast Channel (PBCH) transmission period and the duration of the TTI. At 1004, the base station transmits, within the TTI, a plurality of versions of a Physical Broadcast Channel (PBCH) that includes a second set of bits in a timing reference number that do not change for the duration of the TTI. At 1006, the base station provides an indication of a first set of bits in a timing reference number with each PBCH transmission.

Fig. 11 illustrates example operations 1100 for wireless communications by a User Equipment (UE), e.g., UE120 shown in fig. 1, or some other type of wireless device, e.g., a wireless device acting as a backhaul relay, in accordance with aspects of the present disclosure. For example, the UE may perform operation 1100 to decode timing information transmitted by the BS in accordance with operation 1000.

At 1102, operations 1100 begin by: a first set of one or more bits in a timing reference number transmitted in a PBCH that change over a duration of a Transmission Time Interval (TTI) is determined based on a Physical Broadcast Channel (PBCH) transmission period and the duration of the TTI. At 1104, the UE decodes at least one of a plurality of versions of a Physical Broadcast Channel (PBCH) within the TTI, the plurality of versions including a second set of bits in a timing reference number that do not change for the duration of the TTI. At 1106, the UE obtains an indication of the first set of bits in the timing reference number with each decoded PBCH transmission.

As mentioned above, due to the different TTI and BCH transmission periods, different SFN bits may change within a TTI, depending on the synchronization pattern.

For example, as shown in fig. 12, during initial acquisition in the standalone synchronization mode, PBCH instance 1202 may have a20 msec transmission period and an 80msec BCH TTI.

Figure 13 shows how the PBCH content can change within a TTI (again assuming a 10msec frame). As shown, in the case of a20 msec transmission period, the LSB (bit b0) will not change in each redundancy version, and bits 3-9 will also not change within the 80msec tti. On the other hand, bits 2 and 1(b2 and b1) will change in each transmission cycle.

Thus, to keep the content in each redundancy version the same and allow combining, bits b0 and b3-b9 may be transmitted in the MIB, while bits b1 and b2 may be transmitted separately.

For example, bits b1 and b2 may be transmitted in a synchronization signal, MIB, or DMRS. In some cases, the values of these bits may be transmitted as burst set index or as PBCH redundancy version. In other words, each of four different values (for a 2-bit combination) may be mapped to four different redundancy versions.

As shown, in some cases, to indicate a 5msec (field) boundary (field boundary) within a frame, additional bits may be transmitted (e.g., as a preamble/midamble). In other words, the extra bit may provide a field indication, e.g., indicating one of two fields within a frame.

In some cases, longer transmission periods (e.g., 40,80, or 160msec) may be used for initial acquisition in idle/connected mode or non-standalone mode. In such cases, to allow PBCH combining, the BCH TTI may be increased accordingly for these modes.

For example, fig. 14 shows an example configuration with 160msec BCH TTI, with a transmission period (within the TTI) of 40msec for each PBCH instance 1402.

Fig. 15 shows how the specific SFN bits of the MIB content can also change accordingly in case of 160msec BCH TTI. In this example, bits b1 and b0 would not change in each redundancy version due to the 40msec period of transmission for each PBCH instance. On the other hand, bits b2 and b3 will change. Thus, bits b0-b1 and bits b4-b9 may be transmitted in the MIB, while bits b3 and b2 may be transmitted in another manner as described above to ensure that the content does not change over a longer TTI and that combining may still be performed to enhance decoding performance.

Of course, various combinations of PBCH periods (e.g., 20msec, 40msec) and BCH TTIs (80msec, 160msec) may be used, and the particular SFN bits transmitted in the MIB, rather than via other mechanisms, may be adjusted accordingly. In some cases, 2 bits may be transmitted via the RV and/or DMRS, while 2 bits may be transmitted by a synchronization signal (e.g., SSS).

As described herein, in some cases, a configuration for carrying timing information in the MIB is determined based on the determined PBCH Tx period and BCH TTI. As mentioned above, these parameters may be determined based on the operating mode (e.g., initial acquisition in standalone, for one or more UEs in RRC idle or RRC connected mode, non-standalone).

As demonstrated in the examples described above, the BCH TTI may be selected as an integer number of PBCH Tx instances (e.g., 4 or 2).

In some cases, such information about the periodicity and BCH TTI may be indicated to the UE. For example, the information may be preconfigured (e.g., in a standard specification) for the same cell or neighboring cells via Master Information Block (MIB), System Information Block (SIB), or Radio Resource Control (RRC) message signaling (in other words, one base station may transmit the information while another base station transmits the PBCH).

In a dual connectivity scenario, where devices communicate via at least two different Radio Access Technologies (RATs), information may be communicated in one RAT while the PBCH is sent in another RAT. For example, in LTE-NR dual connectivity mode, information for NR may be provided via LTE. As another example, for a dual connectivity mode involving two types of new radios (NR1-NR2 dual connectivity mode), less than 6GHz NR1 may provide information for more than 6GHz NR 2.

As mentioned in the above-described examples, the timing information transmitted in this way may refer to an SFN (system frame number). In some cases, the transmitted timing information may refer to subframe level timing (e.g., a midamble/preamble to indicate a 5msec boundary) or symbol level timing (e.g., an SS block index within a set of SS bursts).

In any case, the timing indication configuration is determined in a manner that enables combining multiple instances of PBCH within the BCH TTI. As described above, the portion of the timing information indicating the location of the PBCH instance within the BCH TTI may not be explicitly carried in the MIB content, but may be transmitted via other means (e.g., PBCH RV and/or SSS/DMRS/PSS).

In some cases, this timing information may be carried in both PBCH RV and SSS/DMRS/PSS combinations (which means that there is some redundancy). In this case, if the UE can successfully acquire (part of) this information from the SSS/DMRS/PSS, this may reduce the complexity of PBCH processing by avoiding (part of) RV blind detection.

As described in the above example, if the timing information refers to an X-bit SFN (e.g., where X ═ 10), the b bits of the X bits (e.g., b ═ 2) that identify the location of the PBCH instance within the BCH TTI may not be carried in the MIB, but may be transmitted via other means.

Example timing indication by DMRS/PBCH in different modes

According to certain aspects, the timing indication may also (additionally or alternatively) be provided via demodulation reference signal (DMRS) and Physical Broadcast Channel (PBCH) transmissions in different modes.

As described herein, in some cases, a UE may derive (at least in part) a synchronization period (the period of a synchronization burst) through detection of multiple instances of a DMRS. After deriving such information, the UE may use the derived information for PBCH processing (e.g., combining of multiple PBCH transmissions).

In some cases, the DMRS/PBCH scrambling design (in terms of timing indication scheme) may be the same for a first set of synchronization periods, and may be synchronization period-dependent for a second set (of synchronization periods). In other words, for the first set of PBCH TTIs, the design of the DMRS and the scrambling sequence is the same for each PBCH TTI, while for the second set of PBCH TTIs, the design of the DMRS and the scrambling sequence is PBCH TTI dependent.

As described above, the timing information may be provided in MIB (PBCH content), DMRS, SSS, PBCH Redundancy Version (RV). In some cases, the timing information may be provided via a "PBCH scrambling sequence". As one example, instead of (or in addition to) transmitting information via PBCH RV, such information may be transmitted via PBCH scrambling sequences.

Various alternatives exist for communicating timing information via DMRS/PBCH. For example, for the first alternative (Alt 1), in the non-standalone mode or RRC idle/connected mode, the burst set period may take any value of {5,10,20,40,80,160} msec, and DMRS and PBCH scrambling may transmit the same timing information (e.g., b) regardless of the burst set period₂b₁)。

For the second alternative (Alt 2), DMRS and PBCH scrambling may convey different timing information for different burst set periods, e.g.:

5msec period: b₀&1-bit preamble/midamble

10msec period: b₁b₀

20mse period: b₂b₁

40msec period: b₃b₂

80msec period: b₄b₃

160msec period: b₅b₄。

In some cases, in order to enable the UE to acquire timing without ambiguity, a burst set period (3 bits) may also be transmitted in PBCH content.

For the third alternative (Alt 3), DMRS and PBCH scrambling are targeted for signals below a certain threshold (e.g.,<20msec) to transmit the same timing information (e.g., b)₂b₁) And different timing information may be transmitted for larger periods, for example:

40msec period: b₃b₂

80msec period: b₄b₃

160msec period: b₅b₄。

This approach may have certain benefits. For example, using this approach, (1) DMRS and PBCH scrambling randomization may be implemented for all synchronization burst periods below a threshold value (< ═ 20 msec); and (2) PBCH blind decoding may not be required when combining across a burst set.

The methods disclosed herein comprise one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

As used herein, a phrase referring to "at least one of a list of items refers to any combination of those items, including a single member. For example, "at least one of a, b, or c" is intended to encompass any combination of a, b, c, a-b, a-c, b-c, and a-b-c, as well as multiples of the same element (e.g., any other ordering of a, b, and c), a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b-b, b-b-c, c-c, and c-c-c, or a, b, and c).

As used herein, the term "determining" includes a wide variety of actions. For example, "determining" can include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Further, "determining" can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), and so forth. Further, "determining" may include resolving, selecting, establishing, and the like.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more. The term "some" means one or more unless explicitly stated otherwise. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed in accordance with the provisions of 35u.s.c. § 112 clause 6, unless the element is explicitly recited using the phrase "unit for … …", or in the case of a method claim, the element is recited using the phrase "step for … …".

The various operations of the methods described above may be performed by any suitable means that can perform the respective functions. These units may include various hardware and/or software components and/or modules, including but not limited to: a circuit, an Application Specific Integrated Circuit (ASIC), or a processor. Generally, where there are operations shown in the figures, those operations may have corresponding counterpart units plus functional components with similar numbering.

For example, the means for transmitting and/or the means for receiving may include one or more of: a transmit processor 420, a TX MIMO processor 430, a receive processor 438 or antenna 434 of the base station 110, and/or a transmit processor 464, a TX MIMO processor 466, a receive processor 458 or antenna 452 of the user equipment 120. Further, the means for generating, the means for multiplexing, the means for decoding (decoder), and/or the means for applying may comprise one or more processors, e.g., controller/processor 440 of base station 110 and/or controller/processor 480 of user equipment 120.

The various illustrative logical blocks, modules, and circuits described in connection with the disclosure may be implemented or performed with 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 (PLD), 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 commercially available 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.

If implemented in hardware, an example hardware configuration may include a processing system in the wireless node. The processing system may be implemented using a bus architecture. The buses may include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. A bus may connect together various circuits including the processor, the machine-readable medium, and the bus interface. The bus interface may also be used, among other things, to connect a network adapter to the processing system via the bus. The network adapter may be used to implement signal processing functions of the PHY layer. In the case of a user terminal 120 (see fig. 1), a user interface (e.g., keypad, display, mouse, joystick, etc.) may also be connected to the bus. The bus may also connect various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further. The processor may be implemented using one or more general and/or special purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits that can execute software. Those skilled in the art will recognize how best to implement the described functionality for a processing system depending on the particular application and the overall design constraints imposed on the overall system.

If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Software shall be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general processing, including executing software modules stored on a machine-readable storage medium. A computer readable storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. By way of example, the machine-readable medium may include a transmission line, a carrier wave modulated by data, and/or a computer-readable storage medium separate from the wireless node having instructions stored thereon, all of which may be accessed by the processor through a bus interface. Alternatively or in addition, the machine-readable medium or any portion thereof may be integrated into a processor, for example, which may be a cache and/or a general register file. Examples of a machine-readable storage medium may include, by way of example, RAM (random access memory), flash memory, ROM (read only memory), PROM (programmable read only memory), EPROM (erasable programmable read only memory), EEPROM (electrically erasable programmable read only memory), registers, a magnetic disk, an optical disk, a hard drive, or any other suitable storage medium, or any combination thereof. The machine-readable medium may be embodied in a computer program product.

A software module may comprise a single instruction, or many instructions, and may be distributed over several different code segments, among different programs, and across multiple storage media. The computer readable medium may include a plurality of software modules. The software modules include instructions that, when executed by an apparatus, such as a processor, cause a processing system to perform various functions. The software modules may include a sending module and a receiving module. Each software module may be located in a single storage device or distributed across multiple storage devices. For example, when a triggering event occurs, a software module may be loaded from the hard drive into RAM. During execution of the software module, the processor may load some of the instructions into the cache to increase access speed. One or more cache lines may then be loaded into the general register file for execution by the processor. It will be understood that when reference is made below to the functionality of a software module, such functionality is achieved by the processor when executing instructions from the software module.

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 (IR), 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 (disk) and disc (disc), as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy disk andoptical disks, where disks usually reproduce data magnetically, while optical disks reproduce data optically with lasers. Thus, in some aspects, computer-readable media may comprise non-transitory computer-readable media (e.g., tangible)Media). The phrase computer readable medium does not refer to transitory propagating signals. Combinations of the above should also be included within the scope of computer-readable media.

Accordingly, certain aspects may comprise a computer program product for performing the operations presented herein. For example, such a computer program product may include a computer-readable medium having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein.

Further, it should be appreciated that modules and/or other suitable means for performing the methods and techniques described herein can be downloaded and/or otherwise obtained by a user terminal and/or base station as applicable. For example, such a device may be coupled to a server to facilitate communicating means for performing the methods described herein. Alternatively, various methods described herein can be provided via a storage unit (e.g., RAM, ROM, a physical storage medium such as a Compact Disc (CD) or floppy disk, etc.), such that a user terminal and/or base station can obtain the various methods upon coupling or providing the storage unit to the device. Further, any other suitable technique for providing the methods and techniques described herein to a device may be used.

It is to be understood that the claims are not limited to the precise configuration and components shown above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.