阅读说明：本技术 可变随机接入信道（rach）签名映射 (Variable Random Access Channel (RACH) signature mapping ) 是由 S·朴 M·P·约翰威尔逊 V·钱德 骆涛 J·孙 张晓霞 A·钱达马拉卡纳 W·南 于 2020-02-20 设计创作，主要内容包括：本公开的各个方面一般涉及无线通信。在一些方面中,用户装备(UE)可从与同步信号块(SSB)相关联的一个或多个随机接入信道(RACH)签名中选择RACH签名。UE可使用所选RACH签名向基站(BS)传送RACH通信。提供了众多其他方面。(Various aspects of the present disclosure generally relate to wireless communications. In some aspects, a User Equipment (UE) may select a Random Access Channel (RACH) signature from one or more RACH signatures associated with a Synchronization Signal Block (SSB). The UE may transmit RACH communications to a Base Station (BS) using the selected RACH signature. Numerous other aspects are provided.)

1. A method of wireless communication performed by a User Equipment (UE), comprising:

selecting a Random Access Channel (RACH) signature from one or more RACH signatures associated with a Synchronization Signal Block (SSB),

wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB; and

transmitting a RACH communication to a Base Station (BS) using the selected RACH signature.

2. The method of claim 1, wherein the beam type associated with the SSB comprises one of a plurality of beam types, each of the plurality of beam types associated with a beam width that is different from a beam width associated with any other of the plurality of beam types.

3. The method of claim 2, wherein the plurality of beam types comprises: a narrow beam having a beam width in a given dimension, a wider beam having a beam width in the given dimension that is greater than the beam width of the narrow beam in the given dimension, and a widest beam having a beam width in the given dimension that is greater than the beam width of the wider beam in the given dimension.

4. The method of claim 2, wherein the plurality of beam types comprises: at least one vertical beam having a relatively large elevation beamwidth and having a relatively small azimuth beamwidth, at least one horizontal beam having a relatively small elevation beamwidth and having a relatively large azimuth beamwidth, and/or at least one symmetric beam having equal elevation and azimuth beamwidths.

5. The method of claim 1, wherein a number of the one or more RACH signatures is based at least in part on a tier associated with a plurality of beam types associated with the SSB.

6. The method of claim 1, wherein the number of one or more RACH signatures comprises a first RACH signature number if the beam type associated with the SSB comprises a wide beam;

wherein the number of one or more RACH signatures comprises a second RACH signature number if the beam type associated with the SSB comprises a narrow beam; and

wherein the first RACH signature number is different from the second RACH signature number.

7. The method of claim 6, wherein the first number of RACH signatures is greater than the second number of RACH signatures.

8. The method of claim 1, wherein the selected RACH signature comprises:

RACH opportunity and RACH preamble; and

wherein selecting the selected RACH signature comprises:

identifying an SSB index associated with the SSB;

selecting the RACH opportunity based at least in part on the SSB index; and

selecting the RACH preamble for the RACH opportunity from one or more RACH preambles.

9. The method of claim 8, wherein identifying the SSB index comprises:

identifying the SSB index based at least in part on a bitmap included in a signaling communication transmitted from the BS.

10. The method of claim 9, wherein the signaling communication comprises at least one of:

a Radio Resource Control (RRC) communication,

a Master Information Block (MIB),

a System Information Block (SIB),

communication of Remaining Minimum System Information (RMSI), or

Other System Information (OSI) communications.

11. The method of claim 9, wherein the number of RACH opportunities associated with the SSB is indicated by a bit position in the bit map associated with the SSB index.

12. The method of claim 9, wherein the beam type associated with the SSB is indicated by a bit position in the bitmap associated with the SSB index.

13. A method of wireless communication performed by a Base Station (BS), comprising:

transmitting a plurality of Synchronization Signal Blocks (SSBs); and

transmitting a signaling communication indicating respective sets of one or more Random Access Channel (RACH) signatures associated with the plurality of SSBs,

wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

14. The method of claim 13, wherein the signaling communication comprises at least one of:

a Radio Resource Control (RRC) communication,

a Master Information Block (MIB),

a System Information Block (SIB),

communication of Remaining Minimum System Information (RMSI), or

Other System Information (OSI) communications.

15. The method of claim 13, wherein the beam type associated with the SSB comprises one of a plurality of beam types, each of the plurality of beam types associated with a different beam width than a beam width associated with any other of the plurality of beam types.

16. The method of claim 15, wherein the plurality of beam types comprises: a narrow beam having a beam width in a given dimension, a wider beam having a beam width in the given dimension that is greater than the beam width of the narrow beam in the given dimension, and a widest beam having a beam width in the given dimension that is greater than the beam width of the wider beam in the given dimension.

17. The method of claim 15, wherein the plurality of beam types comprises: at least one vertical beam having a relatively large elevation beamwidth and having a relatively small azimuth beamwidth and/or at least one horizontal beam having a relatively small elevation beamwidth and having a relatively large azimuth beamwidth.

18. The method of claim 13, wherein a number of the one or more RACH signatures is based at least in part on a level associated with a plurality of beam types associated with the SSB.

19. The method of claim 13, wherein the number of the one or more RACH signatures associated with the SSB comprises a first RACH signature number if the beam type associated with the SSB comprises a wide beam;

wherein the number of the one or more RACH signatures associated with the SSB comprises a second RACH signature number if the beam type associated with the SSB comprises a narrow beam; and

wherein the first RACH signature number is different from the second RACH signature number.

20. The method of claim 19, wherein the first RACH signature number is greater than the second RACH signature number.

21. The method of claim 13, wherein the one or more RACH signatures associated with the SSB comprise:

a corresponding RACH opportunity and a corresponding RACH preamble,

wherein the respective RACH opportunity is indicated by a bitmap in the signaling communication.

22. The method of claim 21, wherein the respective RACH opportunity is based at least in part on a bit position in the bit map associated with an SSB index associated with the SSB.

23. The method of claim 21, wherein a number of RACH opportunities included in the respective RACH opportunity is based at least in part on a bit position in the bit map associated with an SSB index associated with the SSB.

24. The method of claim 21, wherein the beam type associated with the SSB is indicated by a bit position in the bitmap associated with an SSB index associated with the SSB.

25. A User Equipment (UE) for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

selecting a Random Access Channel (RACH) signature from one or more RACH signatures associated with a Synchronization Signal Block (SSB),

wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB; and

transmitting a RACH communication to a Base Station (BS) using the selected RACH signature.

26. The UE of claim 25, wherein the number of one or more RACH signatures comprises a first RACH signature number if the beam type associated with the SSB comprises a wide beam;

wherein the number of one or more RACH signatures comprises a second RACH signature number if the beam type associated with the SSB comprises a narrow beam; and

wherein the first RACH signature number is different from the second RACH signature number.

27. The UE of claim 26, wherein the first RACH signature number is greater than the second RACH signature number.

28. A Base Station (BS) for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

transmitting a plurality of Synchronization Signal Blocks (SSBs); and

transmitting a signaling communication indicating respective sets of one or more Random Access Channel (RACH) signatures associated with the plurality of SSBs,

wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

29. The BS of claim 28, wherein the number of the one or more RACH signatures associated with the SSB comprises a first RACH signature number if the beam type associated with the SSB comprises a wide beam;

wherein the number of the one or more RACH signatures associated with the SSB comprises a second RACH signature number if the beam type associated with the SSB comprises a narrow beam; and

wherein the first RACH signature number is different from the second RACH signature number.

30. The BS of claim 29, wherein the first RACH signature number is greater than the second RACH signature number.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure relate generally to wireless communications, and more specifically to techniques and apparatus for variable Random Access Channel (RACH) signature mapping.

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, etc.). Examples of such multiple-access techniques include 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, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE). LTE/LTE-advanced is an enhanced set of Universal Mobile Telecommunications System (UMTS) mobile standards promulgated by the third generation partnership project (3 GPP).

A wireless communication network may include a number of Base Stations (BSs) capable of supporting communication for a number of User Equipments (UEs). A User Equipment (UE) may communicate with a Base Station (BS) via a downlink and an uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in greater detail herein, a BS may be referred to as a node B, a gNB, an Access Point (AP), a radio head, a Transmission Reception Point (TRP), a New Radio (NR) BS, a 5G B node, and so on.

The above multiple access techniques have been adopted in various telecommunications standards to provide a common protocol that enables different user equipment to communicate on a city, country, region, and even global level. New Radios (NR), which may also be referred to as 5G, are an enhanced set of LTE mobile standards promulgated by the third generation partnership project (3 GPP). NR is designed to better support mobile broadband internet access by improving spectral efficiency, reducing costs, improving services, utilizing new spectrum, and better integrating with the use of Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) (CP-OFDM) on the Downlink (DL), the use of CP-OFDM and/or SC-FDM on the Uplink (UL) (e.g., also known as discrete fourier transform spread OFDM (DFT-s-OFDM), and other open standards that support beamforming, Multiple Input Multiple Output (MIMO) antenna technology, and carrier aggregation.

SUMMARY

In some aspects, a method of wireless communication performed by a User Equipment (UE) may include: selecting a Synchronization Signal Block (SSB) from one or more Random Access Channel (RACH) signatures associated with the SSB, wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB. The method can comprise the following steps: transmitting a RACH communication to a Base Station (BS) using the selected RACH signature.

In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: a RACH signature is selected from one or more RACH signatures associated with an SSB, wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB. The memory and the one or more processors may be configured to: the RACH communication is transmitted to the BS using the selected RACH signature.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by the one or more processors of the UE, may cause the one or more processors to: a RACH signature is selected from one or more RACH signatures associated with an SSB, wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB. The one or more instructions, when executed by the one or more processors, may cause the one or more processors to transmit a RACH communication to a BS using the selected RACH signature.

In some aspects, an apparatus for wireless communication may comprise: means for selecting a RACH signature from one or more RACH signatures associated with an SSB, wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB. The apparatus may include: means for transmitting a RACH communication to the BS using the selected RACH signature.

In some aspects, a method of wireless communication performed by a BS may comprise: multiple SSBs are transmitted. The method can comprise the following steps: transmitting a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

In some aspects, a BS for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to: multiple SSBs are transmitted. The memory and the one or more processors may be configured to: transmitting a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by the one or more processors of the BS, may cause the one or more processors to: multiple SSBs are transmitted. The one or more instructions, when executed by the one or more processors, may cause the one or more processors to transmit a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in the set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based, at least in part, on a beam type associated with the SSB.

In some aspects, an apparatus for wireless communication may comprise: means for transmitting a plurality of SSBs. The apparatus may include: means for transmitting a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

Aspects generally include methods, devices, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, wireless communication devices, and processing systems substantially as described herein with reference to and as illustrated by the accompanying figures and description.

The foregoing has outlined rather broadly the features and technical advantages of an example in accordance with the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. The features of the concepts disclosed herein, both as to their organization and method of operation, together with associated advantages, will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purpose of illustration and description, and not for the purpose of defining the limits of the claims.

Brief Description of Drawings

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, 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. The same reference numbers in different drawings may identify the same or similar elements.

Fig. 1 is a block diagram conceptually illustrating an example of a wireless communication network in accordance with various aspects of the present disclosure.

Fig. 2 is a block diagram conceptually illustrating an example of a Base Station (BS) in communication with a User Equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 3A is a block diagram conceptually illustrating an example of a frame structure in a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 3B is a block diagram conceptually illustrating an example synchronous communication hierarchy in a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 4 is a block diagram conceptually illustrating an example slot format with a normal cyclic prefix, in accordance with various aspects of the present disclosure.

Fig. 5A-5D are diagrams illustrating one or more examples of variable Random Access Channel (RACH) signature mapping in accordance with various aspects of the present disclosure.

Fig. 6 is a diagram illustrating an example process performed, for example, by a UE, in accordance with various aspects of the present disclosure.

Fig. 7 is a diagram illustrating an example process performed, for example, by a BS, in accordance with various aspects of the present disclosure.

Detailed Description

Various aspects of the disclosure are described more fully below with reference to the accompanying drawings. The present disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein one skilled in the art should appreciate that the scope of the present disclosure is intended to cover any aspect of the present disclosure disclosed herein, whether implemented independently or in combination with any other aspect of the present disclosure. 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 as practiced using other structure, functionality, or structure and functionality in addition to or in addition to the various aspects of the present disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be implemented by one or more elements of a claim.

Several aspects of telecommunications systems will now be presented with reference to various devices and techniques. These apparatus and techniques are described in the following detailed description and are illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

It is noted that 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 in other generation-based communication systems (such as 5G and progeny, including NR technologies).

Fig. 1 is a diagram illustrating a wireless network 100 in which aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. Wireless network 100 may include several BSs 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with User Equipment (UE) and may also be referred to as a base station, NR BS, node B, gNB, 5G B Node (NB), access point, Transmission Reception Point (TRP), and so on. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to a coverage area of a BS and/or a BS subsystem serving that coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another 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. Picocells may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscriptions. A femtocell may cover a relatively small geographic area (e.g., a residence) and may allow restricted access by UEs associated with the femtocell (e.g., UEs in a Closed Subscriber Group (CSG)). The BS for the macro cell may be referred to as a macro BS. A BS for a picocell may be referred to as a pico BS. The BS for the femtocell may be referred to as a femto BS or a home BS. In the example shown in fig. 1, BS 110a may be a macro BS for macro cell 102a, BS 110b may be a pico BS for pico cell 102b, and BS 110c may be a femto BS for femto cell 102 c. A BS may support one or more (e.g., three) cells. The terms "eNB", "base station", "NR BS", "gNB", "TRP", "AP", "node B", "5G NB", and "cell" may be used interchangeably herein.

In some aspects, the cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of the mobile BS. In some aspects, BSs may be interconnected to each other and/or to one or more other BSs or network nodes (not shown) in wireless network 100 by various types of backhaul interfaces, such as direct physical connections, virtual networks, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send the transmission of the data to a downstream station (e.g., the UE or the BS). The relay station may also be a UE that can relay transmissions for other UEs. In the example shown in fig. 1, relay 110d may communicate with macro BS 110a and UE 120d to facilitate communication between BS 110a and UE 120 d. The relay station may also be referred to as a relay BS, a relay base station, 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, relay BSs, 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, a macro BS may have a high transmit power level (e.g., 5 to 40 watts), while a pico BS, a femto BS, and a relay BS may have a lower transmit power level (e.g., 0.1 to 2 watts).

Network controller 130 may be coupled to a set of BSs and may provide coordination and control for these BSs. The network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with each other, directly or indirectly, e.g., via a wireless or wired backhaul.

UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, mobile station, subscriber unit, station, etc. A UE may be a cellular phone (e.g., a smartphone), a Personal Digital Assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop, a cordless phone, a Wireless Local Loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor/device, a wearable device (a smartwatch, a smartgarment, smartglasses, a smartwristband, smartjewelry (e.g., a smartring, a smartband)), an entertainment device (e.g., a music or video device, or a satellite radio), a vehicle component or sensor, a smartmeter/sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

Some UEs may be considered Machine Type Communication (MTC) UEs, or evolved or enhanced machine type communication (eMTC) UEs. 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 base station, another device (e.g., a remote device), or some other entity. A wireless node may provide connectivity for or to a network, e.g., a wide area network such as the internet or a cellular network, e.g., via a wired or wireless communication link. Some UEs may be considered internet of things (IoT) devices and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered Customer Premise Equipment (CPE). UE 120 may be included within a housing that houses components of UE 120, such as a processor component, a memory component, and so forth.

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. A frequency may also be referred to as a carrier, a frequency channel, etc. Each frequency may support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly (e.g., without using base station 110 as an intermediary to communicate with each other) using one or more sidelink channels. For example, the UE 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, a vehicle networking (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, etc.), a mesh network, and so forth. In this case, UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by base station 110.

As indicated above, fig. 1 is provided as an example. Other examples may differ from what is described with respect to fig. 1.

Fig. 2 shows a block diagram of a design 200 of base station 110 and UE 120, where base station 110 and UE 120 may be one of the base stations and one of the UEs in fig. 1. The base station 110 may be equipped with T antennas 234a through 234T, while the UE 120 may be equipped with R antennas 252a through 252R, where T ≧ 1 and R ≧ 1 in general.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more Modulation and Coding Schemes (MCSs) for each UE based at least in part on a Channel Quality Indicator (CQI) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-Static Resource Partitioning Information (SRPI), etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS)) and synchronization signals (e.g., Primary Synchronization Signals (PSS) and Secondary Synchronization Signals (SSS)). A Transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T Modulators (MODs) 232a through 232T. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232T may be transmitted via T antennas 234a through 234T, respectively. According to various aspects described in more detail below, a synchronization signal may be generated utilizing position coding to convey additional information.

At UE 120, antennas 252a through 252r may receive downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254R, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. The channel processor may determine Reference Signal Received Power (RSRP), Received Signal Strength Indicator (RSSI), Reference Signal Received Quality (RSRQ), Channel Quality Indicator (CQI), and the like. In some aspects, one or more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller/processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by Modulators (MODs) 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to base station 110. At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide decoded data to a data sink 239 and decoded control information to controller/processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. Network controller 130 may include a communication unit 294, a controller/processor 290, and a memory 292.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of fig. 2 may perform one or more techniques associated with variable Random Access Channel (RACH) signature mapping, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component(s) of fig. 2 may perform or direct operations of, for example, process 600 of fig. 6, process 700 of fig. 7, and/or other processes as described herein. As such, the memory 282 of the UE may include a non-transitory computer-readable medium storing one or more instructions for wireless communication, wherein the one or more instructions include one or more instructions that, when executed by one or more processors (e.g., the receive processor 258, the transmit processor 264, and/or the controller/processor 280) of the UE 120, cause the one or more processors to perform a method described in more detail with reference to fig. 5A-5D, 6, and/or 6. Further, memory 242 of BS may include a non-transitory computer-readable medium storing one or more instructions for wireless communication, wherein the one or more instructions comprise one or more instructions that, when executed by one or more processors of BS 110 (e.g., transmit processor 220, receive processor 238, and/or controller/processor 240), cause the one or more processors to perform a method described in more detail with reference to fig. 5A-5D, 6, and/or 6. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include: means for selecting a RACH signature from one or more RACH signatures associated with a Synchronization Signal Block (SSB), wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB (e.g., using the receive processor 258, the transmit processor 264, the controller/processor 280, the memory 282, etc.); means for communicating RACH communications to BS 110 using the selected RACH signature (e.g., using memory 282, controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, etc.), and/or the like.

In some aspects, base station 110 may include: means for transmitting a plurality of SSBs (e.g., using memory 242, controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antennas 234, etc.); means for transmitting a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB (e.g., using memory 242, controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, etc.) and/or the like.

As indicated above, fig. 2 is provided as an example. Other examples may differ from what is described with respect to fig. 2.

Fig. 3A illustrates an example frame structure 300 for Frequency Division Duplexing (FDD) in a telecommunication system (e.g., NR). The transmission timeline for each of the downlink and uplink may be partitioned into units of radio frames (sometimes referred to as frames). Each radio frame may have a predetermined duration (e.g., 10 milliseconds (ms)) and may be divided into a set of Z (Z ≧ 1) subframes (e.g., with indices of 0 through Z-1). Each subframe may have a predetermined duration (e.g., 1ms) and may include a set of slots (e.g., 2 per subframe is shown in fig. 3A)^mTime slots, where m is a parameter design for transmission, such as 0, 1,2, 3, 4, etc.). Each slot may include a set of L symbol periods. For example, each slot may include fourteen symbol periods (e.g., as shown in fig. 3A), seven symbol periods, or another number of symbol periods. In the case where a subframe includes two slots (e.g., when m ═ 1), the subframe may include 2L symbol periods, where the 2L symbol periods in each subframe may be assigned indices 0 through 2L-1. In some aspects, the scheduling units for FDD may be frame-based, subframe-based, slot-based, symbol-based, and so on.

Although some techniques are described herein in connection with frames, subframes, slots, etc., the techniques may be equally applicable to other types of wireless communication structures that may be referred to in the 5G NR using terms other than "frame," "subframe," "slot," etc. In some aspects, a wireless communication structure may refer to a periodic time-bounded communication unit defined by a wireless communication standard and/or protocol. Additionally or alternatively, wireless communication fabric configurations other than those shown in fig. 3A may be used.

In some telecommunications (e.g., NR), a base station may transmit a Synchronization (SYNC) signal. For example, a base station may transmit a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and so on the downlink for each cell supported by the base station. The PSS and SSS may be used by the UE for cell search and acquisition. For example, PSS may be used by a UE to determine symbol timing, while SSS may be used by a UE to determine a physical cell identifier associated with a base station and frame timing. The base station may also transmit a Physical Broadcast Channel (PBCH). The PBCH may carry some system information, such as system information supporting initial access of the UE.

In some aspects, a base station may transmit a PSS, an SSs, and/or a PBCH according to a synchronization communication hierarchy (e.g., Synchronization Signal (SS) hierarchy) that includes multiple synchronization communications (e.g., SS blocks), as described below in connection with fig. 3B.

Fig. 3B is a block diagram conceptually illustrating an example SS hierarchy, which is an example of a synchronous communication hierarchy. As shown in fig. 3B, the SS tier may include a set of SS bursts, which may include a plurality of SS bursts (identified as SS burst 0 through SS burst B-1, where B is the maximum number of repetitions of an SS burst that may be transmitted by a base station). As further shown, each SS burst may include one or more SS blocks (identified as SS block 0 through SS block (b)_{Max _ SS-1}) Wherein b is_{Max _ SS-1}Is the maximum number of SS blocks that can be carried by an SS burst). In some aspects, different SS blocks may be beamformed differently. The set of SS bursts may be transmitted periodically by the wireless node, such as every X milliseconds, as shown in fig. 3B. In some aspects, the set of SS bursts may have a fixed or dynamic length, as shown as Y milliseconds in fig. 3B.

The set of SS bursts shown in fig. 3B is an example of a set of synchronous communications, and other sets of synchronous communications may be used in conjunction with the techniques described herein. Further, the SS blocks shown in fig. 3B are examples of synchronous communications, and other synchronous communications may be used in conjunction with the techniques described herein.

In some aspects, SS blocks include resources that carry a PSS, SSs, PBCH, and/or other synchronization signals (e.g., a Third Synchronization Signal (TSS)) and/or synchronization channels. In some aspects, multiple SS blocks are included in an SS burst, and the PSS, SSs, and/or PBCH may be the same across each SS block of an SS burst. In some aspects, a single SS block may be included in an SS burst. In some aspects, an SS block may be at least four symbol periods in length, with each symbol carrying one or more of PSS (e.g., occupying one symbol), SSs (e.g., occupying one symbol), and/or PBCH (e.g., occupying two symbols).

In some aspects, the symbols of the SS block are consecutive, as shown in fig. 3B. In some aspects, the symbols of the SS block are non-coherent. Similarly, in some aspects, one or more SS blocks of an SS burst may be transmitted in consecutive radio resources (e.g., consecutive symbol periods) during one or more time slots. Additionally or alternatively, one or more SS blocks of an SS burst may be transmitted in non-contiguous radio resources.

In some aspects, an SS burst may have a burst period, whereby each SS block of the SS burst is transmitted by a base station according to the burst period. In other words, the SS blocks may be repeated during each SS burst. In some aspects, the set of SS bursts may have a burst set periodicity, whereby individual SS bursts of the set of SS bursts are transmitted by the base station according to a fixed burst set periodicity. In other words, the SS bursts may be repeated during each set of SS bursts.

The base station may transmit system information, such as System Information Blocks (SIBs), on a Physical Downlink Shared Channel (PDSCH) in certain time slots. The base station may transmit control information/data on a Physical Downlink Control Channel (PDCCH) in C symbol periods of a slot, where B may be configurable for each slot. The base station may transmit traffic data and/or other data on the PDSCH in the remaining symbol periods of each slot.

As indicated above, fig. 3A and 3B are provided as examples. Other examples may differ from the examples described with respect to fig. 3A and 3B.

Fig. 4 shows an example slot format 410 with a normal cyclic prefix. The available time-frequency resources may be divided into resource blocks. Each resource block may cover a set of subcarriers (e.g., 12 subcarriers) in one slot and may include several resource elements. Each resource element may cover one subcarrier in one symbol period (e.g., in time) and may be used to transmit one modulation symbol, which may be a real or complex value.

For FDD in some telecommunication systems (e.g., NR), an interleaving structure may be used for each of the downlink and uplink. For example, Q interlaces may be defined with indices of 0 through Q-1, where Q may be equal to 4, 6, 8, 10, or some other value. Each interlace may include slots spaced Q frames apart. Specifically, interlace Q may include slots Q, Q + Q, Q +2Q, etc., where Q ∈ {0, …, Q-1 }.

The UE may be located within the coverage of multiple BSs. One of the BSs may be selected to serve the UE. The serving BS may be selected based at least in part on various criteria, such as received signal strength, received signal quality, path loss, and so on. The received signal quality may be quantified by a channel interference plus noise ratio (SINR), or a Reference Signal Received Quality (RSRQ), or some other metric. The UE may operate in a dominant interference scenario where the UE may observe high interference from one or more interfering BSs.

Although aspects of the examples described herein may be associated with NR or 5G technologies, aspects of the present disclosure may be applicable to other wireless communication systems. A New Radio (NR) may refer to a radio configured to operate according to a new air interface (e.g., different from an Orthogonal Frequency Division Multiple Access (OFDMA) -based air interface) or a fixed transport layer (e.g., different from the Internet Protocol (IP)). In aspects, NR may utilize OFDM with CP (referred to herein as cyclic prefix OFDM or CP-OFDM) and/or SC-FDM on the uplink and CP-OFDM on the downlink and include support for half-duplex operation using Time Division Duplexing (TDD). In aspects, the NR may utilize OFDM with CP (referred to herein as CP-OFDM) and/or discrete fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM), for example, on the uplink, may utilize CP-OFDM on the downlink, and includes support for half-duplex operation using TDD. NR may include enhanced mobile broadband (eMBB) services targeting wide bandwidths (e.g., 80 megahertz (MHz) and above), millimeter wave (mmW) targeting high carrier frequencies (e.g., 60 gigahertz (GHz)), massive MTC (MTC) targeting non-backward compatible MTC technologies, and/or mission critical targeting ultra-reliable low latency communication (URLLC) services.

In some aspects, a single component carrier bandwidth of 100MHZ may be supported. The NR resource block may span 12 subcarriers having a subcarrier bandwidth of 60 or 120 kilohertz (kHz) over a 0.1 millisecond (ms) duration. Each radio frame may include 40 slots and may have a length of 10 ms. Thus, each slot may have a length of 0.25 ms. Each time slot may indicate a link direction (e.g., DL or UL) for data transmission and the link direction for each time slot may be dynamically switched. Each slot may include DL/UL data as well as DL/UL control data.

Beamforming may be supported and beam directions may be dynamically configured. MIMO transmission with precoding may also be supported. MIMO configuration in DL can support up to 8 transmit antennas (multi-layer DL transmission with up to 8 streams) and up to 2 streams per UE. Multi-layer transmission of up to 2 streams per UE may be supported. Aggregation of multiple cells may be supported using up to 8 serving cells. Alternatively, the NR may support a different air interface than the OFDM based interface. The NR network may comprise entities such as central units or distributed units.

As indicated above, fig. 4 is provided as an example. Other examples may differ from what is described with respect to fig. 4.

The UE may access the wireless network by negotiating a connection with a BS included in the wireless network. During connection establishment, the UE and the BS may synchronize the connection in the downlink direction (i.e., from the BS to the UE) and in the uplink direction (i.e., from the UE to the BS).

In order to synchronize the connection in the downlink direction, the UE may read the SSB including various synchronization signals transmitted from the BS. The synchronization signals may include PSS, SSS, etc. The UE may use the PSS to determine symbol timing in the downlink direction and the SSS to determine a physical cell identifier associated with the BS and frame timing.

To synchronize the connection in the uplink direction, the UE and the BS may perform a RACH procedure. In some aspects, the UE and the BS may perform a four-step RACH procedure. In a four-step RACH procedure, the UE and the BS may exchange four primary RACH communications. The UE may transmit msg1 communications to the BS. The msg1 communication may include a RACH preamble communication. The BS may respond to msg1 communications with msg2 communications, which may include Random Access Response (RAR) communications. The UE may respond to the msg2 communication with msg3 communication, which may include a Radio Resource Control (RRC) connection request communication. The BS may respond to the msg3 communication with msg4 communication, which may include a media access control element (MAC-CE) contention resolution identifier, an RRC setup (RRCSetup) command, and so on.

In some cases, the four-step RACH procedure may not meet the low latency requirements of 5G/NR wireless systems. Thus, the UE and the BS may use a two-step RACH procedure to reduce latency for synchronizing connections in the uplink direction. In a two-step RACH procedure, the UE may combine msg1 communication and msg3 communication into a communication called msgA communication. The msg1 portion of the msgA communication may be referred to as the preamble portion of the msgA communication. The msg3 portion of msgA communication may be referred to as the payload portion of msgA. The UE may sequentially transmit the msg1 portion and the msg3 portion before receiving the msg2 communication and the msg4 communication. The BS may receive msgA communications and may transmit msgB communications, which may include msg2 communications and msg4 communications.

In some cases, the UE may transmit uplink RACH communications using a RACH signature (e.g., msg1 communications, preamble portion of msgA communications, etc. in a four-step RACH procedure). The RACH signature may include a combination of RACH preamble (e.g., Zadoff-Chu sequences and/or other types of sequences) and RACH opportunity (e.g., uplink time domain resources and uplink frequency domain resources). The UE may select a RACH signature for transmitting a RACH communication by selecting an SSB associated with a beam transmitted from the BS, selecting a RACH opportunity associated with the SSB, and selecting a RACH preamble from a plurality of available RACH preambles in the RACH opportunity.

In some cases, the BS may transmit various types of beams, such as wide beams, narrow beams, vertical beams (beams having a relatively large elevation width and a relatively small azimuth width), horizontal beams (beams having a relatively large elevation width and a relatively large azimuth width), symmetric beams (beams having similar widths in both elevation and azimuth), wide beams and/or narrow beams of different widths, and so forth. However, the number of RACH signatures associated with the SSB may be the same regardless of the beam type of the beam associated with the SSB, which may result in an inefficient distribution of RACH signatures and/or an increased number of RACH preamble collisions. As an example, a wide beam may serve a greater number of UEs in a cell associated with a BS than a narrow beam due to the directional nature of the narrow beam. If the SSB associated with the wide beam and the SSB associated with the narrow beam are assigned the same number of RACH signatures, the UE served by the wide beam may experience a greater number of RACH preamble collisions because a greater number of UEs are served by the wide beam, and a lower RACH preamble utilization because a lesser number of UEs are served by the narrow beam.

Some aspects described herein provide techniques and apparatus for variable RACH signature mapping. In some aspects, the BS may transmit multiple SSBs. Each SSB may be associated with a respective beam transmitted from the BS. The beam may be associated with a beam type. The BS may transmit a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs. For example, one or more RACH signatures may be defined or determined for a given SSB, such as SSB1, e.g., { RACHsig1_1, RACHsig1_2, …, RACHsig1_ m }, while another SSB, such as SSB2, may be defined or determined, e.g., { RACHsig2_1, RACHsig2_2, …, RACHsig2_ n }, where m and n are integers that may be different. Additionally, for a further given SSB, a respective set of one or more RACH signatures may also be defined or determined. The number of RACH signatures of the one or more RACH signatures associated with the SSB (integers m and n in the examples of SSB1 and SSB2 just discussed) may be based at least in part on the beam type of the beam associated with the SSB. In the example just discussed, the integer value m may be based at least in part on a beam type of a beam associated with the SSB1, and the integer value n may be based at least in part on a beam type of a beam associated with the SSB 2. In this manner, the number of RACH signatures associated with a particular SSB may be variable based at least in part on the beam type of the beam associated with that SSB. This may permit the BS to more flexibly and efficiently assign RACH signatures to SSBs, which may reduce RACH preamble collisions and/or increase RACH preamble utilization.

Fig. 5A-5D are diagrams illustrating an example 500 of variable RACH signature mapping in accordance with various aspects of the present disclosure. As shown in fig. 5A-5D, example 500 may include communication between a user equipment (e.g., UE 120) and a base station (e.g., BS 110). In some aspects, BS 110 and UE 120 may be included in a wireless network (e.g., wireless network 100).

In some aspects, BS 110 and UE 120 may establish a connection using a RACH procedure (such as a four-step RACH procedure, a two-step RACH procedure, etc.). For example, UE 120 may initiate a RACH procedure by transmitting a RACH communication to BS 110. The RACH communications may include msg1 communications in a four-step RACH procedure, msgA communications in a two-step RACH procedure, and so on. In some aspects, UE 120 may select a RACH signature (e.g., a RACH opportunity and a RACH preamble in the RACH opportunity) for RACH communication. The RACH signature may be used to uniquely identify UE 120 during a RACH procedure.

As shown in fig. 5A and by reference numeral 502, BS 110 may transmit multiple SSBs on respective beams (e.g., SSB n 1-SSB n9, SSB w 1-SSB w3, etc.). UE 120 may select one of the SSBs and may select a RACH signature for RACH communication based at least in part on the selected SSB. In some aspects, UE 120 may select an SSB based at least in part on various factors and/or criteria. As an example, UE 120 may perform one or more measurements associated with multiple SSBs and may select the SSB that yields the best measurement, the best combination of measurements, the best average measurement, and so on. The one or more measurements may include a Received Signal Strength Indication (RSSI) measurement, a Reference Signal Received Power (RSRP) measurement, a Reference Signal Received Quality (RSRQ) measurement, a latency measurement, a signal-to-noise ratio (SNR) measurement, a signal-to-interference-plus-noise ratio (SINR) measurement, and/or the like.

The multiple SSBs may each be associated with a respective beam type or set of beam types (e.g., wide beam, narrow beam, vertical beam, horizontal beam, symmetric beam, etc.). In one particular example, the beam type may be one of a plurality of beam types, each of the plurality of beam types associated with a beam width that is different from a beam width associated with any other of the plurality of beam types. As an example, the plurality of beam types may include: a first beam type associated with a narrow beam having a beam width in a given dimension, a second beam type associated with a wider beam having a beam width in the given dimension greater than the beam width of the narrow beam in the given dimension, a third beam type associated with a widest beam having a beam width in the given dimension greater than the beam width of the wider beam in the given dimension. As another example, the plurality of beam types may include a greater or lesser number of beam types associated with varying beamwidths. The different beamwidths may be in a given dimension, e.g., such that each of the plurality of beam types is associated with a beamwidth in the given dimension (e.g., each beam type is associated with a beamwidth in elevation or with a beamwidth in azimuth). Further, different beamwidths may be associated with different numbers of RACH signatures. For example, based on the above example, a beam type associated with a narrow beam may be associated with a first number of RACH signatures (e.g., 4 RACH signatures), a beam type associated with a wider beam may be associated with a second number of RACH signatures (e.g., 5 RACH signatures), a beam type associated with the widest beam may be associated with a third number of RACH signatures (e.g., 6 RACH signatures), and so on. In such examples, the wider beams have more RACH signatures than the narrow beams, such that the third number is greater than the second number and the second number is greater than the first number. In alternative examples, the beam type associated with the narrow beam may be associated with a first number of RACH signatures (e.g., 5 RACH signatures), the beam type associated with the wider beam may be associated with a second number of RACH signatures (e.g., 4 RACH signatures), the beam type associated with the widest beam may be associated with a third number of RACH signatures (e.g., 3 RACH signatures), and so on. In such examples, wider beams have fewer RACH signatures than narrow beams, such that the first number is greater than the second number and the second number is greater than the third number. It should be understood that these examples of RACH signature numbers are merely illustrative.

Additionally or alternatively, some of the different beamwidths may be in different dimensions, e.g., such that one beam type may be a horizontal beam that is relatively wide in azimuth and narrow in elevation, while another beam type may be a vertical beam that is wide in elevation to the same extent that the horizontal beam is wide in azimuth and narrow in azimuth to the same extent that the horizontal beam is narrow in elevation. As such, although the horizontal beam and the vertical beam have similar beam widths, they will be considered as two different beam types because they are rotated relative to each other. Rotations other than 90 degrees may be made between the different types of beams (as in the example of vertical beams versus horizontal beams). Additionally, although the above examples of horizontal beam rotation relative to vertical beam are discussed in the context of beams having similar widths but only rotating, it is understood that some beam types may include any combination of different or similar beam widths in different or similar dimensions (e.g., in elevation and/or azimuth).

In some aspects, the SSBs may be associated with beam types of beams on which the SSBs are transmitted. For example, SSB n2 may be transmitted on a narrow beam and may therefore be associated with a beam type of the narrow beam. As another example, SSB w3 may be transmitted over a wide beam and thus may be associated with a beam type of the wide beam. As another example, SSB n3 may be transmitted on beams that are narrow beams and horizontal beams. Thus, SSB n3 may be associated with a narrow horizontal beam type.

In some aspects, such as in a Licensed Assisted Access (LAA) scenario, beams associated with SSBs may have a close relationship between beams associated with other SSBs. For example, the beam associated with SSB w2 may have a high correlation between the beams associated with SSB w1, SSB w3, SSB n4, SSB n5, and SSB n6, which may be referred to as the SSB request group of SSB w 2. In this case, SSB w2 may be associated with a set of beam types including the beam type associated with the beam on which SSB w2 is transmitted and the respective beam type associated with the respective beam on which SSB w1, SSB w3, SSB n4, SSB n5, and SSB n6 are transmitted.

As shown in fig. 5B and by reference numeral 504, BS 110 may transmit a signaling communication indicating a respective set of one or more RACH signatures associated with the plurality of SSBs. In some aspects, the signaling communication may be unicast, broadcast, multicast, etc. to the UE 120. The signaling communications may include Radio Resource Control (RRC) communications, Master Information Blocks (MIB), System Information Blocks (SIB), Remaining Minimum System Information (RMSI) communications, Other System Information (OSI) communications, and so forth.

In some aspects, the number of RACH signatures used for SSB may be based at least in part on a beam type (or set of beam types) associated with the SSB. For example, different beam types (or different combinations of beam types) may correspond to different RACH signature numbers. For example, SSB w1 may be associated with a beam type of a wide beam and thus may be associated with a first RACH signature number, while SSB n6 may be associated with a beam type of a narrow beam and thus may be associated with a second RACH signature number. The first number of RACH signatures may be different from the second number of RACH signatures. For example, the first RACH signature number may be greater or less than the second RACH signature number.

In some aspects, the number of RACH signatures used for SSB may be based at least in part on the level or rank within a particular beam type. For example, SSB w1, SSB w2, and SSBw3 may be associated with a beam type of the wide beam. SSB w1 may be associated with the widest wide beam, SSB w2 may be associated with the second wide beam, and SSB w3 may be associated with the third wide beam. In this case, SSB w1 may be associated with the maximum number of RACH signatures for SSBs associated with the wide beam, SSB w2 may be associated with the second largest number of RACH signatures for SSBs associated with the wide beam, and SSB w3 may be associated with the third largest number of RACH signatures for SSBs associated with the wide beam. Although the above (and subsequent) discussion may be made with reference to a beam type of a narrow beam and a beam type of a wide beam for ease of explanation, it should be understood that other ways of identifying a beam type are possible. For example, the beam types may be identified by indices such that different beam types are identified as beam _ type (1) (first beam type), beam _ type (2) (second beam type), beam _ type (3) (third beam type), etc., or more generally, beam _ type (i), where index i may be one of a plurality of possible integers indicating different beam widths. In another example, to further summarize, a beam type may be identified by two indices, where each of the two indices indicates a different beamwidth in a different dimension (e.g., a first dimension, such as elevation, and a second dimension, such as azimuth). In such examples, the different beam types are identified as beam _ type (1,1) (the first beam type), beam _ type (1,2), beam _ type (1,3), beam _ type (2,1), etc., or more generally, beam _ type (i, j), where each of indices i and j may be one of a plurality of possible integers indicating different beam widths in the respective dimension. Still further, the beam type may also be identified by, for example, three indices, a first index indicating a beam width in a first dimension, a second index indicating a beam width in a second dimension, and a third index indicating a rotation of the beam. As discussed elsewhere herein, the number of RACH signatures may be based on the beam type associated with the SSB, such that different beam types have different numbers of RACH signatures. For example, a first beam type has a first number of RACH signatures, a second beam type has a second number of RACH signatures, and a third beam type has a third number of RACH signatures, wherein the first, second and third RACH numbers are all different numbers.

In some aspects, in the LAA scenario, the number of RACH signatures used for SSBs may be further based at least in part on the number of SSB request groups associated with the SSBs. For example, SSBs associated with four SSB request groups may be associated with a greater number of RACH signatures relative to SSBs associated with three SSB request groups. Moreover, the number of RACH signatures used for SSB may be further based at least in part on a beam type associated with the SSB request group. For example, SSBs associated with two broad beam SSB request groups and one narrow beam SSB request group may be associated with a different number (e.g., more or less) of RACH signatures than SSBs associated with one broad beam SSB request group and two narrow beam SSB request groups.

In some aspects, the number of RACH signatures for an SSB may be further based at least in part on the number of UEs being served by the beam associated with the SSB, at least in part on the number of UEs expected to be served by the beam, and so on. For example, the number of RACH signatures used for SSB may increase as the number of UEs being served by a beam (and/or expected to be served by a beam) increases, and may decrease as the number of UEs being served by a beam (and/or expected to be served by a beam) decreases.

In some aspects, the respective beam types (and thus the respective numbers of RACH signatures) associated with the multiple SSBs may be indicated by a bitmap in the signaling communication. The bitmap may comprise a ssbpotionsinburst (SSB position in burst) bitmap, where each column represents a respective SSB index for multiple SSBs, and the row of the bitmap may indicate which beam type (or set of beam types) is associated with a particular SSB. For example, SSB n8 may correspond to SSB index 8, and a bit having a value of 1 in the first row and the eighth column of the bitmap may indicate that SSB n8 is associated with a type 1 beam type (e.g., which may be a beam type of a narrow beam). The SSB index associated with the SSB may indicate a time domain location and a frequency domain location of the RACH opportunity included in the RACH signature for the SSB in the uplink radio frame.

As shown in fig. 5C, and as indicated by reference numeral 506, the UE 120 may select a RACH signature for the selected SSB among one or more RACH signatures based at least in part on the signaling communication. In some aspects, to select a RACH signature, UE 120 may determine a RACH configuration of an uplink radio frame using a bitmap and a RACH configuration data structure. The RACH configuration of an uplink radio frame may include one or more RACH opportunities distributed across one or more RACH slots in the uplink radio frame. Each RACH opportunity may be located at a particular time domain location and a particular frequency domain location in a RACH slot in an uplink radio frame. The SSB associated with a particular RACH opportunity may be determined based at least in part on the bit map and the RACH configuration data structure.

For example, the SSB indices may be sequentially assigned to the RACH opportunities included in the uplink radio frame according to one or more RACH configuration parameters specified in the RACH configuration data structure. The RACH configuration data structure may include a table, database, electronic file, etc. received from UE 120 (e.g., from BS 110 and/or from another source in a signaling communication and/or another signaling communication) or configured for UE 120 when UE 120 is deployed in a wireless network. The one or more RACH configuration parameters may include Frequency Division Multiplexing (FDM) parameters, Time Division Multiplexing (TDM) parameters, RACH slot parameters, one or more beam type parameters, and/or the like.

The FDM parameters may specify how the RACH slots are divided in the frequency domain. In the example shown in fig. 5C, an FDM parameter (e.g., "RACH communication-FDM") may specify that for each time domain location, a RACH slot is to be divided into two frequency domain locations. The TDM parameters may specify how the RACH slots are partitioned in the time domain. In the example shown in fig. 5C, a TDM parameter (e.g., "number of time domain RACH opportunities within RACH slot") may specify that a RACH slot is to be divided into three time domain locations. The RACH opportunity may be located at various time domain location and frequency location combinations included in the RACH slot.

The RACH slot parameter may specify the number of RACH slots included in the uplink radio frame. In the example shown in fig. 5C, a RACH slot parameter (e.g., the number of RACH slots per frame) may specify the number of RACH slots per uplink radio frame as 10. For a particular beam type, the beam type parameter may specify the number of RACH opportunities in an uplink radio frame to assign to SSBs of the particular beam type, and the number of RACH preambles available in each RACH opportunity. In the example shown in fig. 5C, for a type 1 beam type, the beam type parameters may specify that the SSB associated with the type 1 beam type is to be assigned four RACH opportunities in an uplink radio frame, and may specify that each RACH opportunity assigned to the SSB is to include 32 RACH preambles.

UE 120 may determine the RACH configuration of the uplink radio frame by sequentially assigning SSBs to RACH opportunities based at least in part on SSB indices associated with the SSBs and based at least in part on one or more parameters specified in a RACH configuration data structure. For example, the UE 120 may determine, based at least in part on the bitmap, that SSB n1 is associated with beam types of SSB index 0 and type 2, and may assign four RACH opportunities to SSB n1 accordingly. In some aspects, UE 120 may assign RACH opportunities first across frequency domain locations and then across time domain locations. For example, in a first RACH slot, UE 120 may assign two RACH opportunities that occupy two frequency domain locations in a first time domain location, and then proceed to the next time domain location to assign RACH opportunities. In some aspects, UE 120 may assign RACH opportunities first across time domain locations and then across frequency domain locations. For example, in a first RACH time slot, UE 120 may assign three RACH opportunities that occupy three of the first frequency-domain locations, and then proceed to the next frequency-domain location to assign RACH opportunities. Once the UE 120 has completed assigning a RACH opportunity to SSB n1, the UE 120 may continue assigning a RACH opportunity to SSB n2, and so on.

UE 120 may select a RACH signature for the selected SSB based at least in part on determining a RACH configuration for the uplink radio frame. For example, the UE 120 may identify an SSB index associated with the selected SSB, which may be associated with a particular column in the bitmap. For example, if the selected SSB is SSB n4, UE 120 may determine that the SSB index associated with SSB n4 (e.g., SSB index 3) corresponds to the fourth column in the bitmap. UE 120 may identify a bit in the fourth column of the bitmap having a value of 1 to determine the beam type associated with the selected SSB. For example, the UE 120 may determine the row in which the bit having a value of 1 is located, which may correspond to the beam type associated with the SSB. In the example illustrated in fig. 5C, a bit having a value of 1 in the fourth column may be located in the first row of the bitmap, which may indicate that SSB n4 is associated with a type 1 beam type (e.g., a narrow beam type).

UE 120 may determine one or more RACH signatures associated with the selected SSB based at least in part on the RACH configuration for the uplink radio frame. For example, UE 120 may determine a location of one or more RACH opportunities associated with the selected SSB based at least in part on the RACH configuration, and may select a RACH opportunity from the one or more RACH opportunities (e.g., the RACH opportunity may be selected randomly, the first available RACH opportunity in the time and frequency domains may be selected, etc.). UE 120 may then select a RACH preamble of the one or more RACH preambles available in the selected RACH opportunity. The combination of the selected RACH opportunity and the selected RACH preamble may be the selected RACH signature.

As shown in fig. 5D and by reference numeral 508, UE 120 may transmit RACH communications using the selected RACH signature. For example, UE 120 may transmit a RACH communication in a RACH opportunity associated with the selected RACH signature and may include a RACH preamble associated with the selected RACH signature in the RACH communication.

In this manner, BS 110 may transmit signaling communications indicating respective sets of one or more RACH signatures associated with multiple SSBs. The number of RACH signatures with respect to one or more RACH signatures associated with an SSB may be based, at least in part, on a beam type of a beam associated with the SSB. In this manner, the number of RACH signatures associated with a particular SSB may be variable based at least in part on the beam type of the beam associated with that SSB. This may permit BS 110 to more flexibly and efficiently assign RACH signatures to SSBs, which may reduce RACH preamble collisions and/or increase RACH preamble utilization.

As indicated above, fig. 5A-5D are provided as examples. Other examples may differ from what is described with respect to fig. 5A-5D.

Fig. 6 is a diagram illustrating an example process 600 performed, for example, by a UE, in accordance with various aspects of the present disclosure. The example process 600 is an example in which a UE (e.g., UE 120) performs operations associated with variable RACH signature mapping.

As shown in fig. 6, in some aspects, process 600 may include selecting a RACH signature from one or more RACH signatures associated with an SSB, wherein a number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB (block 610). For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, etc.) may select a RACH signature from one or more RACH signatures associated with the SSB, as described, for example, with reference to fig. 5A, 5B, 5C, and/or 5D. In some aspects, the number of the one or more RACH signatures is based at least in part on a beam type associated with the SSB.

As further illustrated in fig. 6, in some aspects, process 600 may include transmitting RACH communications to the BS using the selected RACH signature (block 620). For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, etc.) may transmit RACH communications to the BS using the selected RACH signature, as described, for example, with reference to fig. 5A, 5B, 5C, and/or 5D.

Process 600 may include additional aspects, such as any single implementation or any combination of aspects described below and/or in conjunction with one or more other processes described elsewhere herein.

In a first aspect, the beam type associated with the SSB includes one of a plurality of beam types, each of the plurality of beam types associated with a beam width that is different from a beam width associated with any other of the plurality of beam types. In a second aspect, alone or in combination with the first aspect, the plurality of beam types comprises: a narrow beam having a beam width in a given dimension, a wider beam having a beam width in the given dimension that is greater than the beam width of the narrow beam in the given dimension, and a widest beam having a beam width in the given dimension that is greater than the beam width of the wider beam in the given dimension.

In a third aspect, alone or in combination with one or more of the first or second aspects, the plurality of beam types comprises: at least one vertical beam having a relatively large elevation beamwidth and having a relatively small azimuth beamwidth and/or at least one horizontal beam having a relatively small elevation beamwidth and having a relatively large azimuth beamwidth. It should be understood that in the context of vertical or horizontal beams, in some examples, one dimension having a relatively large beamwidth and another dimension having a relatively small beamwidth may refer to the relatively large beamwidth being larger than the relatively small beamwidth, even though it may not be considered large in absolute value. Similarly, in some examples, a relatively small beamwidth may simply mean that it is smaller than a relatively large beamwidth, even though it is not considered small in absolute value. In some cases, the plurality of beam types may include at least one symmetric beam having equal or approximately equal elevation and azimuth beamwidths.

In a fourth aspect, alone or in combination with one or more of the first to third aspects, the number of the one or more RACH signatures is based at least in part on a tier associated with a plurality of beam types associated with the SSB. In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, the number of one or more RACH signatures comprises a first RACH signature number if the beam type associated with the SSB comprises a broad beam. In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, the number of one or more RACH signatures comprises a second number of RACH signatures if the beam type associated with the SSB comprises a narrow beam. In a seventh aspect, the first number of RACH signatures is different from the second number of RACH signatures, alone or in combination with one or more of the first to sixth aspects. In an eighth aspect, the first number of RACH signatures is greater than the second number of RACH signatures, alone or in combination with one or more of the first to seventh aspects.

In a ninth aspect, the RACH signature comprises a RACH opportunity and a RACH preamble, either alone or in combination with one or more of the first to eighth aspects. In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, selecting a RACH signature comprises identifying an SSB index associated with an SSB, the selected RACH opportunity being selected based at least in part on the SSB index; and selecting the selected RACH preamble for the RACH opportunity from the one or more RACH preambles. In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, identifying the SSB index comprises identifying the SSB index based at least in part on a bitmap included in a signaling communication transmitted from the BS. In a twelfth aspect, the signaling communication comprises at least one of an RRC communication, an MIB, an SIB, an RMSI communication, or an OSI communication, alone or in combination with one or more of the first to eleventh aspects.

In a thirteenth aspect, the number of RACH opportunities associated with the SSB is indicated by a bit position in the bit map associated with the SSB index, alone or in combination with one or more of the first to twelfth aspects. In a fourteenth aspect, either alone or in combination with one or more of the first through thirteenth aspects, the beam type associated with the SSB is indicated by a bit position in the bit map associated with the SSB index.

Although fig. 6 shows example blocks of the process 600, in some aspects the process 600 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in fig. 6. Additionally or alternatively, two or more blocks of the process 600 may be performed in parallel.

Fig. 7 is a diagram illustrating an example process 700, e.g., performed by a BS, in accordance with various aspects of the present disclosure. Example process 700 is an example where a BS (e.g., BS 110) performs operations associated with variable RACH signature mapping.

As shown in fig. 7, in some aspects, process 700 may include transmitting a plurality of SSBs (block 710). For example, the BS (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, etc.) may transmit multiple SSBs as described, for example, with reference to fig. 5A, 5B, 5C, and/or 5D.

As further illustrated in fig. 7, in some aspects, process 700 may include transmitting a signaling communication indicating respective sets of one or more RACH signatures associated with the plurality of SSBs, wherein a number of RACH signatures in a set of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB (block 720). For example, the BS (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, etc.) may transmit a signaling communication indicating a respective set of one or more RACH signatures associated with the plurality of SSBs, as described, for example, with reference to fig. 5A, 5B, 5C, and/or 5D. In some aspects, a number of one or more RACH signatures associated with an SSB of the plurality of SSBs is based at least in part on a beam type associated with the SSB.

Process 700 may include additional aspects, such as any single implementation or any combination of aspects described below and/or in conjunction with one or more other processes described elsewhere herein.

In a first aspect, the signaling communication includes at least one of the following. In a second aspect, RRC communication, MIB, SIB, RMSI communication or OSI communication, alone or in combination with the first aspect. In a third aspect, alone or in combination with one or more of the first or second aspects, the beam type associated with the SSB comprises one of a plurality of beam types, each of the plurality of beam types associated with a beam width that is different from a beam width associated with any other of the plurality of beam types.

In a fourth aspect, alone or in combination with one or more of the first to third aspects, the plurality of beam types comprises: a narrow beam having a beam width in a given dimension, a wider beam having a beam width in the given dimension that is greater than the beam width of the narrow beam in the given dimension, and a widest beam having a beam width in the given dimension that is greater than the beam width of the wider beam in the given dimension. In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, the plurality of beam types comprises: at least one vertical beam having a relatively large elevation beamwidth and having a relatively small azimuth beamwidth and/or at least one horizontal beam having a relatively small elevation beamwidth and having a relatively large azimuth beamwidth.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the number of the one or more RACH signatures is based at least in part on a tier associated with a plurality of beam types associated with the SSB. In a seventh aspect, either alone or in combination with one or more of the first through sixth aspects, the number of one or more RACH signatures associated with the SSB comprises a first RACH signature number if the beam type associated with the SSB comprises a broad beam, and the number of one or more RACH signatures associated with the SSB comprises a second RACH signature number if the beam type associated with the SSB comprises a narrow beam. In an eighth aspect, the first number of RACH signatures is different from the second number of RACH signatures, alone or in combination with one or more of the first to seventh aspects. In a ninth aspect, the first number of RACH signatures is greater than the second number of RACH signatures, alone or in combination with one or more of the first to eighth aspects.

In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the one or more RACH signatures associated with the SSB comprise a respective RACH opportunity and a respective RACH preamble. In an eleventh aspect, the respective RACH opportunity is indicated by a bitmap in the signaling communication, alone or in combination with one or more of the first to tenth aspects. In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, the respective RACH opportunity is based at least in part on a bit position in the bit map associated with the SSB index associated with the SSB. In a thirteenth aspect, the number of RACH opportunities included in a respective RACH opportunity is based at least in part on a bit position in the bit map associated with the SSB index associated with the SSB, either alone or in combination with one or more of the first through twelfth aspects. In a fourteenth aspect, either alone or in combination with one or more of the first through thirteenth aspects, the beam type associated with the SSB is indicated by a bit position in the bit map associated with the SSB index associated with the SSB.

Although fig. 7 shows example blocks of the process 700, in some aspects the process 700 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in fig. 7. Additionally or alternatively, two or more blocks of process 700 may be performed in parallel.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit aspects to the precise form disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practicing various aspects.

As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, and/or a combination of hardware and software.

It will be apparent that the systems and/or methods described herein may be implemented in various forms of hardware, firmware, and/or combinations of hardware and software. The actual specialized control hardware or software code used to implement the systems and/or methods is not limiting in every respect. Thus, the operation and behavior of the systems and/or methods were described herein without reference to the specific software code-it being understood that software and hardware may be designed to implement the systems and/or methods based, at least in part, on the description herein.

Although particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of the various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each of the dependent claims listed below may be directly dependent on only one claim, the disclosure of the various aspects includes each dependent claim in combination with each other claim in the set of claims. A phrase referring to "at least one of a list of items" refers to any combination of these items, including a single member. By way of example, "at least one of a, b, or c" is intended to encompass: a. b, c, a-b, a-c, b-c, and a-b-c, and any combination of multiple identical elements (e.g., 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 any other ordering of a, b, and c).

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles "a" and "an" are intended to include one or more items, and may be used interchangeably with "one or more. Further, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, non-related items, combinations of related and non-related items, etc.) and may be used interchangeably with "one or more. Where only one item is intended, the phrase "only one" or similar language is used. Also, as used herein, the terms "having," "containing," "including," and the like are intended to be open-ended terms. Further, the phrase "based on" is intended to mean "based, at least in part, on" unless explicitly stated otherwise.