WO2021120083A1

WO2021120083A1 - Beam indication for downlink control information scheduled sidelink transmission

Info

Publication number: WO2021120083A1
Application number: PCT/CN2019/126521
Authority: WO
Inventors: Qiaoyu Li; Chao Wei; Min Huang; Jing Dai; Hao Xu; Huilin Xu; Wanshi Chen
Original assignee: Qualcomm Inc
Current assignee: Qualcomm Inc
Priority date: 2019-12-19
Filing date: 2019-12-19
Publication date: 2021-06-24
Anticipated expiration: 2022-06-19

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a remote user equipment (UE) may receive downlink control information indicating a beam to be used for a physical sidelink control channel carrying sidelink control information on a sidelink between the remote UE and a set of relay UEs. The remote UE may communicate with the set of relays UEs using the indicated beam. Numerous other aspects are provided.

Description

[Title established by the ISA under Rule 37.2] BEAM INDICATION FOR DOWNLINK CONTROL INFORMATION SCHEDULED SIDELINK TRANSMISSION

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for beam indication for a downlink control information (DCI) scheduled sidelink transmission.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and/or the like) . Examples of such multiple-access technologies 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 a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) . A user equipment (UE) may communicate with a base station (BS) via the downlink and 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 more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP) , a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New Radio (NR) , which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP) . NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL) , using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the uplink (UL) , 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 increase, there exists a need for further improvements in LTE and NR technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies.

SUMMARY

In some aspects, a method of wireless communication, performed by a base station, may include identifying a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote UE and a set of relay UEs; and transmitting downlink control information (DCI) indicating the beam to be used for the PSCCH carrying the SCI.

In some aspects, a method of wireless communication, performed by a remote UE, may include receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE and a set of relay UEs; and communicating with the set of relays UEs using the indicated beam.

In some aspects, a method of wireless communication, performed by a relay UE, may include receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and the relay UE; and communicating with the remote UE using the indicated beam.

In some aspects, a base station for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to identify a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and a set of relay UEs; and transmit DCI indicating the beam to be used for the PSCCH carrying the SCI.

In some aspects, a remote UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE and a set of relay UEs; and communicate with the set of relays UEs using the indicated beam.

In some aspects, a relay UE for wireless communication may include memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and the relay UE; and communicate with the remote UE using the indicated beam.

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 one or more processors of a base station, may cause the one or more processors to: identify a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and a set of relay UEs; and transmit DCI indicating the beam to be used for the PSCCH carrying the SCI.

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 one or more processors of a remote UE, may cause the one or more processors to: receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE and a set of relay UEs; and communicate with the set of relays UEs using the indicated beam.

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 one or more processors of a relay UE, may cause the one or more processors to: receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and the relay UE; and communicate with the remote UE using the indicated beam.

In some aspects, an apparatus for wireless communication may include means for identifying a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and a set of relay UEs; and means for transmitting DCI indicating the beam to be used for the PSCCH carrying the SCI.

In some aspects, an apparatus for wireless communication may include means for receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the apparatus and a set of relay UEs; and means for communicating with the set of relays UEs using the indicated beam.

In some aspects, an apparatus for wireless communication may include means for receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and the apparatus; and means for communicating with the remote UE using the indicated beam.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the 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. Characteristics of the concepts disclosed herein, both 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 purposes of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that 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. 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 in communication with a UE in a wireless communication network, in accordance with various aspects of the present disclosure.

Figs. 3A and 3B are diagrams illustrating examples of beam indication for a DCI scheduled sidelink transmission, in accordance with various aspects of the present disclosure.

Fig. 4 is a diagram illustrating an example process performed, for example, by a base station, in accordance with various aspects of the present disclosure.

Fig. 5 is a diagram illustrating an example process performed, for example, by a remote user equipment, in accordance with various aspects of the present disclosure.

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

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This 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 disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using 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.

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

It should be noted that while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, 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. The wireless network 100 may include a number of 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 (UEs) and may also be referred to as a base station, a NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , and/or the like. 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 this 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 subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in Fig. 1, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (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, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, 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 a transmission of the data to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in Fig. 1, a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 Watts) .

A network controller 130 may couple to a set of BSs and may provide coordination and control for these BSs. Network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with one another, e.g., directly or indirectly via a wireless or wireline 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, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., a smart phone) , a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, 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, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) 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 a Customer Premises Equipment (CPE) . UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like.

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, an air interface, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. Each frequency may support a single RAT in a given geographic area in order 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 using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another) . For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like) , a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.

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

Fig. 2 shows a block diagram of a design 200 of base station 110 and UE 120, which may be one of the base stations and one of the UEs in Fig. 1. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.

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 (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS (s) 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) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS) ) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (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 and/or the like) 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, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252a through 252r may receive the 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 and/or the like) 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. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , and/or 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 (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. 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 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , 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 the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Network controller 130 may include communication unit 294, controller/processor 290, and 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 beam indication for a DCI scheduled sidelink transmission, 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 400 of Fig. 4, process 500 of Fig. 5, process 600 of Fig. 6, and/or other processes as described herein.

Memories

242 and 282 may store data and program codes for base station 110 and UE 120, respectively. In some aspects, memory 242 and/or memory 282 may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed by one or more processors of the base station 110 and/or the UE 120, may perform or direct operations of, for example, process 400 of Fig. 4, process 500 of Fig. 5, process 600 of Fig. 6, and/or other processes as described herein. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, a remote UE 120 may include means for receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE 120 and a set of relay UEs 120; means for communicating with the set of relays UEs 120 using the indicated beam; and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with Fig. 2, such as controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.

In some aspects, relay UE 120 may include means for receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE 120 and the relay UE 120; means for communicating with the remote UE 120 using the indicated beam; and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with Fig. 2, such as controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.

In some aspects, base station 110 may include means for identifying a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE 120 and a set of relay UEs 120; means for transmitting DCI indicating the beam to be used for the PSCCH carrying the SCI; and/or the like. In some aspects, such means may include one or more components of base station 110 described in connection with Fig. 2, such as antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, and/or the like.

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

In an NR network, it may be desirable to support so-called mid-tier NR functionality (referred to herein as NR-Light) that can be used, for example, to enable UEs of relatively low cost and/or low complexity to utilize the NR network. Such a UE may include, for example, a high-end MTC device (e.g., a security camera, a wearable device, and/or the like) , a high-end IoT device, or a relatively low cost 5G device. NR-Light may enable a UE to communicate using a reduced transmit power (e.g., uplink transmit power of an NR-Light UE may be up to 10 decibels (dB) less than that used by a conventional NR UE) , using a single transmit antenna, using a reduced amount of bandwidth (e.g., 5 megahertz (MHz) to 20 MHz both transmit and receive) , using a reduced number of receive antennas (e.g., a single receive antenna) , and with reduced computational complexity.

Further, a UE may be capable of maintaining two links in some cases: a link to a base station via a cellular air interface (e.g., a Uu interface) , and a sidelink to one or more other devices (e.g., one or more other UEs) . Here, the sidelink may support direct device-to-device communication (e.g., rather than communication via a base station) . Sidelink communications operate using a physical sidelink control channel (PSCCH) that is to carry sidelink control information (SCI) . The SCI may be used to schedule a physical sidelink shared channel (PSSCH) for carrying device-to-device communications.

In some cases, a UE can use a sidelink to extend communication coverage and/or increase channel throughput to the cellular network. In such a case, a UE that uses the sidelink to achieve extended coverage and/or increased throughput may be referred to as a remote UE, while a UE that enables extended coverage and/or increased throughput for the remote UE can be referred to as a relay UE. The remote UE can maintain both the Uu link (with a base station) and the sidelink (with a set of relay UEs) because coverage of the cellular network is broader than that of the sidelink, and because sidelink communication has a relatively low power consumption. In some cases, a capacity of a sidelink (e.g., via frequency range 2 (FR2) ) may be relatively large (e.g., approximately 10 megabits per second (Mbps) ) due to a relatively close distance between the remote UE and the set of relay UEs, while a Uu capacity for a given relay UE may be relatively small (e.g., approximately 2.5 Mbps per relay UE, since each relay UE needs other remaining capacity for its own usage) . Typically, Uu capacity for the remote UE is even smaller (e.g., approximately 500 kilobits per second (Kbps) ) due to fewer antennas and/or the use of lower transmit power by the remote UE. In some cases, multiple relay UEs can jointly assist the remote UE in order to achieve increased throughput.

However, a manner in which a set of relay UEs is selected for supporting a remote UE via a sidelink (e.g., when multiple sets or relay UEs may be available for supporting the remote UE) , as well as a manner in which the remote UE and the set of relay UEs determine beams to be used for the sidelink, must be defined in order to enable a sidelink to be used for extending communication coverage and/or increasing channel throughput to the cellular network for a remote UE.

Some aspects described herein provide techniques and apparatuses for beam indication for a downlink control information (DCI) scheduled sidelink transmission. In some aspects, sidelink beam determination, and therefore relay UE selection, may be performed by a base station, and the base station may transmit information associated with the sidelink beams to the remote UE and the set of relay UEs.

In some aspects, performance of sidelink beam determination and relay UE selection by a base station may eliminate a need for information exchange between the remote UE and relay UEs in association with determining relay UE grouping, thereby conserving network resources, UE power, and preventing an increase in signaling overhead. Similarly, performance of sidelink beam determination and relay UE selection by the base station may be beneficial since the base station has access to information (e.g., information related to Uu capacities) based on which such relay UE selection and/or sidelink beam determination is performed, thereby conserving network resources and preventing an increase in signaling overhead.

Figs. 3A and 3B are diagrams illustrating examples associated with beam indication for a DCI scheduled sidelink transmission, in accordance with various aspects of the present disclosure.

As shown in Fig. 3A by reference 305, a base station (e.g., base station 110) may identify a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE (e.g., a remote UE 120) and a set of relay UEs (e.g., a set of relay UEs 120) .

In some aspects, the base station may identify the beam based at least in part on capacity information associated with the set of relay UEs. An example associated with identifying the beam based at least in part on capacity information associated with the set of relay UEs is provided in Fig. 3B. As illustrated in Fig. 3B, the base station may have access to information indicating that a sidelink capacity of a first potential set of relay UEs (e.g., the left set of relay UEs in Fig. 3B) is 12.9 Mbps, and that a total relay capacity of the first potential set of relay UEs is 6.3 Mbps (e.g., 1.7 Mbps + 1.7 Mbps + 1.6 Mbps + 1.3 Mbps = 6.3 Mbps) . The base station may also have access to information indicating that a sidelink capacity of a second potential set of relay UEs (e.g., the right set of relay UEs in Fig. 3B) is 10.5 Mbps, and that a total relay capacity of the second potential set of relay UEs is 12.4 Mbps (e.g., 2.9 Mbps + 3.3 Mbps + 3.0 Mbps + 3.2 Mbps = 12.4 Mbps) . In this case, as indicated in Fig. 3B, 10 Mbps of capacity is needed between the remote UE and the base station (which is greater than the 500 Kbps provided by a Uu link between the remote UE and the base station) . Therefore, as indicated in Fig. 3B, the base station may identify the beam to be used for the PSCCH as the beam associated with the second potential set of relay UEs (e.g., since the sidelink capacity and the relay capacity are both greater than 10 Mbps) .

Returning to Fig. 3A, and as shown by reference 310, the base station may transmit DCI indicating the beam to be used for the PSCCH carrying the SCI. In some aspects, the DCI may be transmitted to the remote UE. In some aspects, the DCI may be transmitted to the set of relay UEs associated with the identified beam. In some aspects, the base station may transmit the DCI to a given UE (e.g., a remote UE and/or a given one of the set of relay UEs) via a Uu link between the base station and the given UE.

In some aspects, as indicated above, the beam indicated by the DCI is a beam that is to be used for a PSCCH that is to carry SCI associated with the sidelink between the remote UE and the set of relay UEs. In some aspects, the beam may also be a beam that is to be used for a physical sidelink shared channel (PSSCH) scheduled by the SCI. That is, in some aspects, a PSSCH scheduled by the SCI may be assumed to use the same beam that is to be used for the PSCCH.

In some aspects, the beam may be a transmit beam for the remote UE and a receive beam for the set of relay UEs. That is, the beam indicated by the DCI may be a transmit beam from the perspective of the remote UE, and a receive beam from the perspective of the set of relay UEs. In some aspects, when the beam is to be a transmit beam for the remote UE, the beam may be indicated using a sounding reference signal (SRS) resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE. That is, in some aspects, an SRS resource indicator associated with a previous SRS resource set (e.g., used to track different relay UEs) may be used for indicating a transmit beam to the remote UE (and for indicating a receive beam to the set of relay UEs) . In some aspects, when the beam is to be a transmit beam for the remote UE, the beam may be indicated using a synchronization signal block (SSB) index corresponding to a sidelink SSB transmitted by the remote UE. That is, in some aspects, an SSB index of the remote UE may be used for indicating a transmit beam to the remote UE (and for indicating a receive beam to the set of relay UEs) .

In some aspects, the beam may be a receive beam for the remote UE and a transmit beam for the set of relay UEs. That is, the beam indicated by the DCI may be a receive beam from the perspective of the remote UE, and a transmit beam from the perspective of the set of relay UEs. In some aspects, when the beam is to be a receive beam for the remote UE, the beam may be indicated using a sidelink quasi co-location (QCL) indication associated with a reference signal. That is, in some aspects, a sidelink QCL configuration/indication scheme may be used in association with indicating the beam (and for indicating a transmit beam to the set of relay UEs) . In some aspects, when the beam is to be a receive beam for the remote UE, the beam may be indicated using an SSB index corresponding to an SSB. That is, in some aspects, an SSB index of the remote UE may be used for indicating a receive beam to the remote UE (and for indicating a transmit beam to the set of relay UEs) .

As further shown in Fig. 3A, and by reference 315, the remote UE and/or a relay UE, included in the set of relay UEs, may receive the DCI indicating the beam to be used for the PSCCH carrying the SCI on the sidelink, and may communicate using the indicated beam. For example, when the indicated beam is a transmit beam for the remote UE, the remote UE may transmit, and one or more of the set of relay UEs may receive, a sidelink communication (e.g., a PSCCH communication, a PSSCH communication, and/or the like) using the beam. As another example, when the indicated beam is a receive beam for the remote UE, one or more of the set of relay UEs may transmit, and the remote UE may receive, a sidelink communication (e.g., a PSCCH communication, a PSSCH communication, and/or the like) using the beam.

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

Fig. 4 is a diagram illustrating an example process 400 performed, for example, by a base station, in accordance with various aspects of the present disclosure. Example process 400 is an example where the base station (e.g., base station 110 and/or the like) performs operations associated with beam indication for a DCI scheduled sidelink transmission.

As shown in Fig. 4, in some aspects, process 400 may include identifying a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and a set of relay UEs (block 410) . For example, the base station (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, and/or the like) may identify a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE (e.g., a remote UE 120) and a set of relay UEs (e.g., a set of relay UEs 120) , as described above.

As further shown in Fig. 4, in some aspects, process 400 may include transmitting DCI indicating the beam to be used for the PSCCH carrying the SCI (block 420) . For example, the base station (e.g., using transmit processor 220, controller/processor 240, memory 242, and/or the like) may transmit DCI indicating the beam to be used for the PSCCH carrying the SCI, as described above.

Process 400 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, the beam is to be used for a PSSCH scheduled by the SCI.

In a second aspect, alone or in combination with the first aspect, the DCI is transmitted to the remote UE.

In a third aspect, alone or in combination with one or more of the first and second aspects, the DCI is transmitted to the set of relay UEs.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the beam is to be a transmit beam for the remote UE and a receive beam for the set of relay UEs.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the beam is indicated using an SRS resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the beam is indicated using an SSB index corresponding to a sidelink SSB transmitted by the remote UE.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the beam is to be a receive beam for the remote UE and a transmit beam for the set of relay UEs.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the beam is indicated using a sidelink quasi co-location indication associated with a reference signal.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the beam is indicated using an SSB index corresponding to an SSB.

Although Fig. 4 shows example blocks of process 400, in some aspects, process 400 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 4. Additionally, or alternatively, two or more of the blocks of process 400 may be performed in parallel.

Fig. 5 is a diagram illustrating an example process 500 performed, for example, by a remote UE, in accordance with various aspects of the present disclosure. Example process 500 is an example where the remote UE (e.g., UE 120 and/or the like) performs operations associated with beam indication for a DCI scheduled sidelink transmission.

As shown in Fig. 5, in some aspects, process 500 may include receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE and a set of relay UEs (block 510) . For example, the UE (e.g., using receive processor 258, controller/processor 280, memory 282, and/or the like) may receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between the remote UE and a set of relay UEs (e.g., a set of relay UEs 120) , as described above.

As further shown in Fig. 5, in some aspects, process 500 may include communicating with the set of relays UEs using the indicated beam (block 520) . For example, the remote UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may communicate with the set of relays UEs using the indicated beam, as described above.

Process 500 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, the beam is to be used for a PSSCH scheduled by the SCI.

In a second aspect, alone or in combination with the first aspect, the beam is to be a transmit beam for the remote UE and a receive beam for the set of relay UEs.

In a third aspect, alone or in combination with one or more of the first and second aspects, the beam is indicated using an SRS resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the beam is indicated using an SSB index corresponding to a sidelink SSB transmitted by the remote UE.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the beam is to be a receive beam for the remote UE and a transmit beam for the set of relay UEs.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the beam is indicated using a sidelink quasi co-location indication associated with a reference signal.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the beam is indicated using a synchronization signal block (SSB) index corresponding to an SSB.

Although Fig. 5 shows example blocks of process 500, in some aspects, process 500 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 5. Additionally, or alternatively, two or more of the blocks of process 500 may be performed in parallel.

Fig. 6 is a diagram illustrating an example process 600 performed, for example, by a relay UE, in accordance with various aspects of the present disclosure. Example process 600 is an example where the relay UE (e.g., UE 120 and/or the like) performs operations associated with beam indication for a DCI scheduled sidelink transmission.

As shown in Fig. 6, in some aspects, process 600 may include receiving DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE and the relay UE (block 610) . For example, the relay UE (e.g., using receive processor 258, controller/processor 280, memory 282, and/or the like) may receive DCI indicating a beam to be used for a PSCCH carrying SCI on a sidelink between a remote UE (e.g., a UE 120) and the relay UE, as described above.

As further shown in Fig. 6, in some aspects, process 600 may include communicating with the remote UE using the indicated beam (block 620) . For example, the relay UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may communicate with the remote UE using the indicated beam, as described above.

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

In a first aspect, the beam is to be used for a PSSCH scheduled by the SCI.

In a second aspect, alone or in combination with the first aspect, the beam is to be a transmit beam for the remote UE and a receive beam for the relay UE.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the beam is to be a receive beam for the remote UE and a transmit beam for the relay UE.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the beam is indicated using an SSB index corresponding to an SSB.

Although Fig. 6 shows example blocks of process 600, in some aspects, 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 of the blocks of process 600 may be performed in parallel.

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

As used herein, the term “component” is intended to be broadly construed 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.

As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

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

Even though 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 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 dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. A phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, 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. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , 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 “has, ” “have, ” “having, ” and/or 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.

Claims

A method of wireless communication performed by a base station, comprising:

identifying a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote user equipment (UE) and a set of relay UEs; and

transmitting downlink control information (DCI) indicating the beam to be used for the PSCCH carrying the SCI.
The method of claim 1, wherein the beam is to be used for a physical sidelink shared channel (PSSCH) scheduled by the SCI.
The method of claim 1, wherein the DCI is transmitted to the remote UE.
The method of claim 1, wherein the DCI is transmitted to the set of relay UEs.
The method of claim 1, wherein the beam is to be a transmit beam for the remote UE and a receive beam for the set of relay UEs.
The method of claim 5, wherein the beam is indicated using a sounding reference signal (SRS) resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE.
The method of claim 5, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to a sidelink SSB transmitted by the remote UE.
The method of claim 1, wherein the beam is to be a receive beam for the remote UE and a transmit beam for the set of relay UEs.
The method of claim 8, wherein the beam is indicated using a sidelink quasi co-location indication associated with a reference signal.
The method of claim 8, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to an SSB.
A method of wireless communication performed by a remote user equipment (UE) , comprising:

receiving downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between the remote UE and a set of relay UEs; and

communicating with the set of relays UEs using the indicated beam.
The method of claim 11, wherein the beam is to be used for a physical sidelink shared channel (PSSCH) scheduled by the SCI.
The method of claim 11, wherein the beam is to be a transmit beam for the remote UE and a receive beam for the set of relay UEs.
The method of claim 13, wherein the beam is indicated using a sounding reference signal (SRS) resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE.
The method of claim 13, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to a sidelink SSB transmitted by the remote UE.
The method of claim 11, wherein the beam is to be a receive beam for the remote UE and a transmit beam for the set of relay UEs.
The method of claim 16, wherein the beam is indicated using a sidelink quasi co-location indication associated with a reference signal.
The method of claim 16, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to an SSB.
A method of wireless communication performed by a relay user equipment (UE) , comprising:

receiving downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote UE and the relay UE; and

communicating with the remote UE using the indicated beam.
The method of claim 19, wherein the beam is to be used for a physical sidelink shared channel (PSSCH) scheduled by the SCI.
The method of claim 19, wherein the beam is to be a transmit beam for the remote UE and a receive beam for the relay UE.
The method of claim 21, wherein the beam is indicated using a sounding reference signal (SRS) resource indicator corresponding to one or more SRS resources included in an SRS resource set associated with the remote UE.
The method of claim 21, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to a sidelink SSB transmitted by the remote UE.
The method of claim 19, wherein the beam is to be a receive beam for the remote UE and a transmit beam for the relay UE.
The method of claim 24 wherein the beam is indicated using a sidelink quasi co-location indication associated with a reference signal.
The method of claim 24, wherein the beam is indicated using a synchronization signal block (SSB) index corresponding to an SSB.
A base station 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:

identify a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote user equipment (UE) and a set of relay UEs; and

transmit downlink control information (DCI) indicating the beam to be used for the PSCCH carrying the SCI.
A remote 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:

receive downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between the remote UE and a set of relay UEs; and

communicate with the set of relays UEs using the indicated beam.
A relay 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:

receive downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote UE and the relay UE; and

communicate with the remote UE using the indicated beam.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising:

one or more instructions that, when executed by one or more processors of a base station, cause the one or more processors to:

identify a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote user equipment (UE) and a set of relay UEs; and

transmit downlink control information (DCI) indicating the beam to be used for the PSCCH carrying the SCI.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising:

one or more instructions that, when executed by one or more processors of a remote user equipment (UE) , cause the one or more processors to:

receive downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between the remote UE and a set of relay UEs; and

communicate with the set of relays UEs using the indicated beam.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising:

one or more instructions that, when executed by one or more processors of a relay user equipment (UE) , cause the one or more processors to:

receive downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote UE and the relay UE; and

communicate with the remote UE using the indicated beam.
An apparatus for wireless communication, comprising:

means for identifying a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote user equipment (UE) and a set of relay UEs; and

means for transmitting downlink control information (DCI) indicating the beam to be used for the PSCCH carrying the SCI.
An apparatus for wireless communication, comprising:

means for receiving downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between the apparatus and a set of relay UEs; and

means for communicating with the set of relays UEs using the indicated beam.
An apparatus for wireless communication, comprising:

means for receiving downlink control information (DCI) indicating a beam to be used for a physical sidelink control channel (PSCCH) carrying sidelink control information (SCI) on a sidelink between a remote UE and the apparatus; and

means for communicating with the remote UE using the indicated beam.