Control Information for Sidelink Spatial Domain Multiplexing from Multiple Transmit Receive Points (TRPs)

Abstract

Methods, systems, and devices for wireless communication at a user equipment (UE) are described. A first user equipment (UE) may send sidelink control information (SCI) to a second UE that includes an indication of resources and the number of spatial layers for sidelink transmission. The first UE may perform spatial domain multiplexing (SDM) between the spatial layers. The first UE may send a first data packet associated with a first spatial layer from a first transmit receive point (TRP) and may send a second data packet associated with a second spatial layer from a second TRP. In some examples, the first UE may include a first phase and a second phase of the SCI such that the first SCI corresponds to shared information for all spatial layers and the second phase of the SCI corresponds to separate information for each spatial layer.

Description

Technical Field

[0001] The following relates to wireless communication at a user equipment (UE), including control information for sidelink spatial domain multiplexing from multiple transmit receive points (TRPs). Background Art

[0002] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, etc. These systems can support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multi-access systems include fourth generation (4G) systems (e.g., Long Term Evolution (LTE) systems, enhanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as New Radio (NR) systems). These systems may employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multi-access communication system may include one or more base stations or one or more network access nodes, each of which simultaneously supports communication for multiple communication devices (which may also be referred to as user equipment (UE)).

[0003] Some wireless communication systems may support a UE having multiple transmit / receive points (TRPs) that may be spatially separated. In some cases, a multi-TRP UE may use each TRP to transmit and receive in different directions, and transmissions from different TRPs may have different directional characteristics. Summary of the Invention

[0004] The described techniques relate to improved methods, systems, devices, and apparatuses for supporting control information for sidelink spatial domain multiplexing from multiple transmit receive points (TRPs). Generally, the described techniques enable a multi-TRP user equipment (UE) to communicate with other UEs on a sidelink connection using spatial domain multiplexing (SDM). A multi-TRP UE (such as a vehicle) may use common control information to schedule sidelink packets for simultaneous transmission by spatially separated TRPs. For example, a multi-TRP UE may determine that two data packets may be spatially multiplexed and may select overlapping sidelink resources (e.g., time resources, frequency resources, etc.) for transmitting the two data packets to one or more other UEs. Different spatial layers may be mapped to each data packet. In some examples, the multi-TRP UE may select resources such that the SDM transmission is scheduled on the same transmission time interval (TTI) or subframe. The multi-TRP UE may send sidelink control information, which may include common and individual parameters for each spatial layer and / or data packet. Simultaneous SDM transmissions using the same control channel and set of resources for joint transmission may result in throughput gains, lower latency communication, and more efficient use of channel resources.

[0005] A method for wireless communication at a UE is described. The method may include: sending sidelink control information that signals a set of resources and a number of spatial layers for a sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; using the set of resources and based on the indication of spatial domain multiplexing to send a first data packet from a first TRP on the first spatial layer of the sidelink transmission; and using the set of resources and based on the indication of spatial domain multiplexing to send a second data packet from a second TRP on the second spatial layer of the sidelink transmission.

[0006] An apparatus for wireless communication at a UE is described. The apparatus may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: send sidelink control information that signals a set of resources and a number of spatial layers for a sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; use the set of resources and based on the indication of spatial domain multiplexing to send a first data packet from a first TRP on the first spatial layer of the sidelink transmission; and use the set of resources and based on the indication of spatial domain multiplexing to send a second data packet from a second TRP on the second spatial layer of the sidelink transmission.

[0007] Describes another apparatus for wireless communication at a UE. The apparatus may include: a unit for transmitting sidelink control information, the sidelink control information signaling a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; a unit for transmitting a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing; and a unit for transmitting a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0008] Describes a non-transitory computer-readable medium storing code for wireless communication at a UE. The code may include instructions executable by a processor to perform the following operations: transmit sidelink control information, the sidelink control information signaling a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; transmit a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing; and transmit a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0009] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, units, or instructions for performing the following: assign a first hybrid automatic repeat request (HARQ) process identifier to the first spatial layer and assign a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0010] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the indication of spatial domain multiplexing includes using a shared first phase of the sidelink control information and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

[0011] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning a common modulation and coding scheme to a first spatial layer and a second spatial layer, wherein a first shared phase of sidelink control information signals the common modulation and coding scheme.

[0012] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning the common modulation and coding scheme may be based on the size of a first data packet and the size of a second data packet relative to a resource set.

[0013] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the common modulation and coding scheme corresponds to a subchannel size available for sidelink transmission.

[0014] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode a first data packet and a second data packet respectively, wherein sidelink control information signals the separate modulation and coding schemes.

[0015] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting sidelink control information may include operations, features, units, or instructions for: transmitting a first shared phase of sidelink control information, the first shared phase indicating separate modulation and coding schemes for the first spatial layer and the second spatial layer.

[0016] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting sidelink control information may include operations, features, units, or instructions for: transmitting a second separate phase of sidelink control information for the first spatial layer and the second spatial layer using the respective separate modulation and coding schemes.

[0017] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the transmit-side link control information may include operations, features, units, or instructions for performing the following: a first shared phase of the transmit-side link control information, the first shared phase indicating a common modulation and coding scheme for respective separate second phases for decoding a first spatial layer and a second spatial layer; and respective separate second phases of the transmit-side link control information using the common modulation and coding scheme, wherein a second phase of the side-link control information for the first spatial layer indicates one of the separate modulation and coding schemes for decoding a first data packet, and wherein a second phase of the side-link control message for the second spatial layer indicates one of the separate modulation and coding schemes for decoding a second data packet.

[0018] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, units, or instructions for performing the following: assigning the separate modulation and coding schemes may be based on the sizes of the first data packet and the second data packet relative to a resource set.

[0019] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, units, or instructions for performing the following: assigning different demodulation reference signal ports to the first spatial layer and the second spatial layer, wherein the side-link control information signals the different demodulation reference signal ports.

[0020] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the side-link control information signals a shared reservation priority for the first spatial layer and the second spatial layer.

[0021] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the side-link control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

[0022] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, units, or instructions for performing the following: assigning separate destination identifiers to the first spatial layer and the second spatial layer, wherein the side-link control information signals the separate destination identifiers.

[0023] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, units, or instructions for performing the following: assigning separate broadcast types to the first spatial layer and the second spatial layer, wherein the side-link control information signals the separate broadcast types.

[0024] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning separate new data indicators to a first spatial layer and a second spatial layer, wherein the sidelink control information signals the separate new data indicators.

[0025] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning separate communication range indicators to a first spatial layer and a second spatial layer, wherein the sidelink control information includes the separate communication range indicators.

[0026] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: determining a set of resources for sidelink transmission based on the measured signal strength associated with each of a first TRP and a second TRP.

[0027] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the set of resources includes the same transmission time interval for the first TRP and the second TRP.

[0028] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, determining the set of resources may include operations, features, units, or instructions for: selecting a reservation size of the set of resources based on the larger of a first data packet or a second data packet.

[0029] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, determining the set of resources may include operations, features, units, or instructions for: adjusting a resource exclusion signal strength threshold to enable transmission of a first spatial stream at a first TRP and transmission of a second spatial stream at a second TRP.

[0030] A method for wireless communication at a UE is described. The method may include: receiving sidelink control information that signals a set of resources for sidelink transmission and a number of spatial layers, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; receiving a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing; and receiving a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0031] Describes an apparatus for wireless communication at a UE. The apparatus may include a processor, a memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to perform the following operations: receive sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; receive a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing; and receive a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0032] Describes another apparatus for wireless communication at a UE. The apparatus may include: a unit for receiving sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; a unit for receiving a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing; and a unit for receiving a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0033] Describes a non-transitory computer-readable medium storing code for wireless communication at a UE. The code may include instructions executable by a processor to perform the following operations: receive sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; receive a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing; and receive a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0034] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning a first HARQ process identifier to a first spatial layer and assigning a second HARQ process identifier to a second spatial layer, wherein an indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0035] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, an indication of spatial domain multiplexing includes using a shared first phase of sidelink control information and a separate second phase of sidelink control information for the first spatial layer and the second spatial layer.

[0036] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: determining a common modulation and coding scheme for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the common modulation and coding scheme.

[0037] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: determining separate modulation and coding schemes for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate modulation and coding schemes.

[0038] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: determining different demodulation reference signal ports for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

[0039] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the sidelink control information signals a shared reservation priority for the first spatial layer and the second spatial layer.

[0040] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the sidelink control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

[0041] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: determining respective destination identifiers for a first spatial layer and a second spatial layer, wherein the sidelink control information signals separate destination identifiers.

[0042] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: determining respective broadcast types for a first spatial layer and a second spatial layer, wherein the sidelink control information signals the respective broadcast types.

[0043] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving sidelink control information may include operations, features, units, or instructions for: receiving new data indicators for a first spatial layer and a second spatial layer, wherein the sidelink control information signals separate new data indicators.

[0044] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, units, or instructions for: assigning separate communication range indicators to a first spatial layer and a second spatial layer, wherein the sidelink control information includes the separate communication range indicators. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 FIG. 4C illustrates an example of a wireless communication system supporting control information for sidelink spatial domain multiplexing from multiple transmit receive points (TRPs) in accordance with aspects of the present disclosure.

[0046] Figure 2 FIG. 4D illustrates an example of a wireless communication system supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure.

[0047] Figure 3 and 4A FIG. 4C illustrates an example of a communication scheme supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure.

[0048] Figure 5 FIG. 4E illustrates an example of a process flow supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure.

[0049] Figure 6 and 7Block diagram of a device showing control information that supports sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure.

[0050] Figure 8 Block diagram of a communication manager showing control information that supports sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure.

[0051] Figure 9 Diagram of a system including a device showing control information that supports sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure.

[0052] Figures 10 to 13 Flowchart illustrating a method showing control information that supports sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure. Detailed Description

[0053] In some examples, a wireless communication system (e.g., a vehicle-to-everything (V2X) system) may support one or more user equipment (UEs) (e.g., UEs associated with a vehicle) equipped with two or more transmit receive points (TRPs). Such UEs may communicate with each other using sidelink communication. The TRPs on the same vehicle may be separated by a distance, which may be limited by the size of the vehicle. For example, a first TRP may be located at the front of the vehicle, and a second TRP may be located at the rear of the vehicle. Due to factors such as the use of line-of-sight (LoS) channels versus non-line-of-sight (NLoS) channels, blockages, etc., the spatial separation of the transmitting TRPs may introduce differences in how the different receiving TRPs view the channel. Additionally, the packets transmitted or received by each TRP may have different direction requirements. The direction requirements may be based on the direction of the received transmission, application instructions, network configuration, etc.

[0054] To overcome channel differences and account for the directional requirements of packets, a multi-TRP UE (such as a vehicle) can use spatial domain multiplexing (SDM) to simultaneously transmit or receive multiple data packets in a directional manner. For example, a multi-TRP UE can use SDM to simultaneously transmit two or more data packets using two or more TRPs. When preparing for an SDM transmission, the multi-TRP UE can utilize a common control channel to signal the simultaneous transmission and determine the resources for the data packets. In some cases, the data packets can be transmitted on the same or overlapping sets of frequency resources. The data packets can be transmitted during the same transmission time interval (TTI). The data packets can include the same information (e.g., having the same payload) or can be different. In some cases, the multi-TRP UE can map the simultaneous SDM transmissions to different spatial layers and determine a common control information message, such as a sidelink control information (SCI) message. The multi-TRP UE can map the SDM transmission to two (or more) spatial layers. For example, the multi-TRP UE can map the first transmission to spatial layer 1 and the second transmission to spatial layer 2. The mapped transmissions can correspond to different application data, destinations, etc. In some examples, in the common SCI message, the multi-TRP UE can include an indication of whether the two transmissions are mapped to the same layer or different layers.

[0055] In some other examples, the multi-TRP UE can assign a common phase 1 control (SCI-1) message and a separate phase 2 control (SCI-2) message to the data packets. The SCI-1 and SCI-2 messages can each include an indication of parameters for one or two data packets. For example, SCI-1 can indicate whether multiple MCSs can be used for different spatial layers. When multiple MCSs can be used, the multi-TRP UE can encode each transmission separately and provide a list of the MCSs for the corresponding decoding for each spatial layer in SCI-2. Additionally or alternatively, the multi-TRP UE can indicate different HARQ process identifiers for each spatial layer, an indication of the priority for each data packet, a DMRS port indication, a transmission destination identifier, etc.

[0056] In some examples, a multi-TRP UE may indicate priorities for each spatial layer. In some cases, a multi-TRP UE may use the SCI to reserve future resources for upcoming transmissions. In such cases, the priority indication may also affect the reserved future resources. That is, a multi-TRP UE may indicate the highest priority of the spatial layer in SCI-1, where future reservations may be excluded based on the indicated highest priority. For example, if the first data packet has priority 1 and the second data packet has priority 2 (e.g., a priority lower than priority 1), the multi-TRP UE may indicate priority 1 in SCI-1 and may exclude future resources according to priority 1. Alternatively, the multi-TRP UE may indicate the highest priority among data packets in SCI-1, but future reservations may be configured by separate priorities. For example, each future reservation may have an additional field including a priority. The exclusion or preemption of each future resource may be evaluated on a per-packet basis.

[0057] The receiving UE may determine whether the receiving UE should decode one or both of the SDM transmissions. The receiving UE may use common control information (e.g., SCI-1) to decode one or all of the multiplexed data packets. Determining whether the UE should decode the transmission may be based on identifying the HARQ process ID and the source and destination IDs as provided in the common control message. If the receiving UE identifies the HARQ process ID, source ID, or destination ID associated with it, it may decode the transmission corresponding to that ID. The receiving UE may ignore all transmissions specified by source or destination IDs that do not correspond to the receiving UE.

[0058] Simultaneous SDM transmissions using the same control channel and resource set for joint transmission may result in throughput gains, lower latency communication, and more efficient use of channel resources.

[0059] Aspects of the present disclosure are first described in the context of a wireless communication system. Then, aspects of the present disclosure are illustrated by communication schemes and process flows. Aspects of the present disclosure are further illustrated and described with reference to diagrams of apparatuses, system diagrams, and flowcharts related to control information for sidelink spatial domain multiplexing from multiple transmit receive points (TRPs).

[0060] Figure 1An example of a wireless communication system 100 that supports control information for sidelink spatial domain multiplexing from multiple transmit receive points (TRPs) in accordance with aspects of the present disclosure is shown. The wireless communication system 100 may include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an enhanced LTE (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communication, ultra-reliable (e.g., mission-critical) communication, low-latency communication, or communication with low-cost and low-complexity devices, or any combination thereof.

[0061] The base stations 105 may be dispersed throughout a geographic area to form the wireless communication system 100 and may be devices of different forms or having different capabilities. The base stations 105 and the UEs 115 may communicate wirelessly via one or more communication links 125. Each base station 105 may provide a coverage area 110, and the UEs 115 and the base stations 105 may establish one or more communication links 125 over the coverage area 110. The coverage area 110 may be an example of a geographic area over which the base stations 105 and the UEs 115 may support the transmission of signals according to one or more radio access technologies.

[0062] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices of different forms or having different capabilities. In Figure 1 Some example UEs 115 are shown. The UEs 115 described herein are capable of communicating with various types of devices, such as other UEs 115, base stations 105, or network devices (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network devices), as Figure 1 shown in.

[0063] The base stations 105 may communicate with the core network 130, or with each other, or both. For example, the base stations 105 may interface with the core network 130 via one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). The base stations 105 may communicate with each other directly (e.g., directly between the base stations 105) or indirectly (e.g., via the core network 130) via the backhaul links 120 (e.g., via X2, Xn, or other interfaces), or both. In some examples, the backhaul links 120 may be or include one or more wireless links.

[0064] One or more of the base stations 105 described herein may include or may be referred to by those skilled in the art as a base station transceiver, radio base station, access point, radio transceiver, Node B, evolved Node B (eNB), next-generation Node B, or Gigabit Node B (either may be referred to as a gNB), home Node B, home evolved Node B, or some other suitable term.

[0065] The UE 115 may include or may be referred to as a mobile device, wireless device, remote device, handheld device, or subscriber device, or some other suitable term, where the "device" may also be referred to as a unit, station, terminal, or client, etc. The UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, personal digital assistant (PDA), tablet computer, laptop computer, or personal computer. In some examples, the UE 115 may include or be referred to as a wireless local loop (WLL) station, Internet of Things (IoT) device, Internet of Everything (IoE) device, or machine type communication (MTC) device, etc., which may be implemented in various items such as appliances, or vehicles, meters, etc.

[0066] The UE 115 described herein is capable of communicating with various types of devices, such as other UE 115s that can sometimes act as relays, as well as base stations 105 and network devices, including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, etc., as Figure 1 shown.

[0067] The UE 115 and the base station 105 may communicate wirelessly with each other via one or more communication links 125 on one or more carriers. The term "carrier" may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication link 125. For example, a carrier for the communication link 125 may include a portion of a radio frequency spectrum band (e.g., a bandwidth part (BWP), which operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating the operation of the carrier, user data, or other signaling. The wireless communication system 100 may support communication with the UE 115 using carrier aggregation or multi-carrier operation. According to a carrier aggregation configuration, the UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used with both frequency division duplex (FDD) component carriers and time division duplex (TDD) component carriers.

[0068] The communication link 125 shown in the wireless communication system 100 may include an uplink transmission from the UE 115 to the base station 105, or a downlink transmission from the base station 105 to the UE 115. A carrier may carry downlink or uplink communications (e.g., in FDD mode) or may be configured to carry both downlink and uplink communications (e.g., in TDD mode).

[0069] A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or the wireless communication system 100. For example, the carrier bandwidth may be one of several defined bandwidths for a carrier of a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz)). Devices of the wireless communication system 100 (e.g., the base station 105, the UE 115, or both) may have a hardware configuration that supports communication on a particular carrier bandwidth or may be configurable to support communication on one of a set of carrier bandwidths. In some examples, the wireless communication system 100 may include a base station 105 or a UE 115 that supports simultaneous communication via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate on a portion (e.g., a subband, a BWP) or all of the carrier bandwidth.

[0070] The signal waveform transmitted on a carrier may be composed of multiple subcarriers (e.g., using a multi-carrier modulation (MCM) technique such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system employing an MCM technique, a resource element may include a symbol period (e.g., the duration of one modulation symbol) and one subcarrier, where the symbol period and the subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both). Thus, the more resource elements the UE 115 receives and the higher the order of the modulation scheme, the higher the data rate for the UE 115 can be. Wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial layers may further increase the data rate or data integrity for communication with the UE 115.

[0071] It may be in a basic time unit, which may, for example, refer to T s = 1 / (Δf max ·N f ) seconds of sampling period, where Δf max may represent the maximum supported subcarrier spacing, and N fThe time intervals for the base station 105 or the UE 115 can be represented as multiples of the maximum supported discrete Fourier transform (DFT) size. The time intervals of communication resources can be organized according to radio frames, each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame can be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0072] Each frame can include a plurality of consecutively numbered subframes or time slots, and each subframe or time slot can have the same duration. In some examples, a frame can be divided (e.g., in the time domain) into subframes, and each subframe can be further divided into a number of time slots. Alternatively, each frame can include a variable number of time slots, and the number of time slots can depend on the subcarrier spacing. Each time slot can include a number of symbol periods (e.g., depending on the length of the cyclic prefix added before each symbol period). In some wireless communication systems 100, a time slot can be further divided into a plurality of mini-slots each containing one or more symbols. Excluding the cyclic prefix, each symbol period can contain one or more (e.g., N f ones) sampling periods. The duration of a symbol period can depend on the subcarrier spacing or the operating frequency band.

[0073] A subframe, time slot, mini-slot, or symbol can be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and can be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) can be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 can be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

[0074] Physical channels can be multiplexed on a carrier according to various techniques. For example, one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques can be used to multiplex physical control channels and physical data channels on a downlink carrier. A control region for a physical control channel (e.g., a control resource set (CORESET)) can be defined by the number of symbol periods and can extend across the system bandwidth of the carrier or a subset of the system bandwidth. One or more control regions (e.g., CORESETs) can be configured for a group of UEs 115. For example, one or more of the UEs 115 can monitor or search a control region for control information according to one or more search space sets, and each search space set can include one or more control channel candidates at one or more aggregation levels arranged in a cascaded manner. The aggregation level for a control channel candidate can refer to the number of control channel resources (e.g., control channel elements (CCEs)) associated with the coded information for a control information format having a given payload size. The search space set can include a common search space set configured to send control information to multiple UEs 115 and a UE-specific search space set for sending control information to a particular UE 115.

[0075] Each base station 105 can provide communication coverage via one or more cells (e.g., macro cells, small cells, hotspots, or other types of cells, or any combination thereof). The term "cell" can refer to a logical communication entity for communicating with a base station 105 (e.g., via a carrier) and can be associated with an identifier for distinguishing adjacent cells (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other identifier). In some examples, a cell can also refer to a geographic coverage area 110 or a portion of the geographic coverage area 110 (e.g., a sector) on which the logical communication entity operates. Depending on various factors (such as the capabilities of the base station 105), the range of such a cell can vary from a relatively small area (e.g., a building, a subset of a building) to a relatively large area. For example, a cell can be or include a building, a subset of a building, or an external space between or overlapping the geographic coverage areas 110, etc.

[0076] Macro cells typically cover a relatively large geographical area (e.g., with a radius of several kilometers) and can allow unrestricted access by UEs 115 having a service subscription with the network provider that supports the macro cell. In comparison with macro cells, small cells can be associated with lower-power base stations 105, and small cells can operate in the same or different (e.g., licensed, unlicensed) frequency bands as macro cells. Small cells can provide unrestricted access to UEs 115 having a service subscription with the network provider, or can provide restricted access to UEs 115 associated with the small cell (e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associated with users in a residence or office). A base station 105 can support one or more cells and can also support communication on one or more cells using one or more component carriers.

[0077] In some examples, a carrier can support multiple cells and can be configured with different cells according to different protocol types that can provide access for different types of devices (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)).

[0078] In some examples, the base station 105 can be movable and, thus, provide communication coverage for a mobile geographical coverage area 110. In some examples, different geographical coverage areas 110 associated with different technologies can overlap, but different geographical coverage areas 110 can be supported by the same base station 105. In other examples, overlapping geographical coverage areas 110 associated with different technologies can be supported by different base stations 105. The wireless communication system 100 can include, for example, a heterogeneous network where different types of base stations 105 use the same or different radio access technologies to provide coverage for respective geographical coverage areas 110.

[0079] The wireless communication system 100 can support synchronous or asynchronous operation. For synchronous operation, the base stations 105 can have similar frame timings, and transmissions from different base stations 105 can be approximately aligned in time. For asynchronous operation, the base stations 105 can have different frame timings, and in some examples, transmissions from different base stations 105 can not be aligned in time. The techniques described herein can be used for synchronous operation or asynchronous operation.

[0080] Some UEs 115 (e.g., MTC or IoT devices) can be low-cost or low-complexity devices and can provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC can refer to data communication technologies that allow devices to communicate with each other or with the base station 105 without human intervention. In some examples, M2M communication or MTC can include communication from devices integrated with sensors or meters to measure or capture information and relay such information to a central server or application, where the application utilizes the information or presents the information to a human who interacts with the application. Some UEs 115 can be designed to collect information or implement automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, device monitoring, healthcare monitoring, wildlife monitoring, climate and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business billing.

[0081] Some UEs 115 can be configured to operate in a power-reduced mode of operation, such as half-duplex communication (e.g., a mode that supports one-way communication via transmission or reception rather than simultaneous transmission and reception). In some examples, half-duplex communication can be performed at a reduced peak rate. Other power-saving techniques for UEs 115 include entering a power-saving deep sleep mode when not participating in active communication, operating on a limited bandwidth (e.g., according to narrowband communication), or a combination of these techniques. For example, some UEs 115 can be configured for operation using a narrowband protocol type associated with a defined portion or range within a carrier, within a guard band of the carrier, or external to the carrier (e.g., a set of subcarriers or resource blocks (RBs)).

[0082] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication, or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC) or mission-critical communication. The UE115 can be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission-critical functions). Ultra-reliable communication can include private communication or group communication and can be supported by one or more mission-critical services such as mission-critical push-to-talk (MCPTT), mission-critical video (MCVideo), or mission-critical data (MCData). Support for mission-critical functions can include prioritization of services, and mission-critical services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission-critical, and ultra-reliable low-latency can be used interchangeably herein.

[0083] In some examples, UE 115 is also capable of communicating directly with other UEs 115 via a device-to-device (D2D) or sidelink communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115 utilizing D2D communication may be within the geographic coverage area 110 of the base station 105. Other UEs 115 in such a group may be outside the geographic coverage area 110 of the base station 105 or otherwise unable to receive transmissions from the base station 105. In some examples, groups of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system, where each UE 115 transmits to each other UE 115 in the group. In some examples, the base station 105 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without involving the base station 105.

[0084] In some systems, the sidelink communication link 135 may be an example of a communication channel (such as a sidelink communication channel) between vehicles (e.g., UE 115). In some examples, vehicles may communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination of these. Vehicles may signal information related to traffic conditions, signal scheduling, weather, safety, emergencies, or any other information related to the V2X system. In some examples, vehicles in a V2X system may communicate with roadside infrastructure (such as a roadside unit), or communicate with a network via one or more network nodes (e.g., the base station 105) using vehicle-to-network (V2N) communication, or perform both operations.

[0085] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) and at least one user plane entity that routes packets to or interconnects with an external network (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)). The control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management for a UE 115 served by a base station 105 associated with the core network 130. User IP packets may be transmitted through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, an intranet, an IP multimedia subsystem (IMS), or packet-switched streaming services.

[0086] Some network devices in the network equipment (e.g., the base station 105) may include sub-components such as an access network entity 140, which may be an example of an access node controller (ANC). Each access network entity 140 may communicate with a UE 115 through one or more other access network transmission entities 145 (which may be referred to as radio heads, intelligent radio heads, or transmit / receive points (TRPs)). Each access network transmission entity 145 may include one or more antenna panels. In some configurations, the various functions of each access network entity 140 or the base station 105 may be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., the base station 105).

[0087] The wireless communication system 100 may operate using one or more frequency bands (generally in the range of 300 megahertz (MHz) to 300 gigahertz (GHz)). Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or the decimeter band because the wavelength range is approximately from one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features, but these waves can penetrate buildings sufficiently to enable a macro cell to serve a UE 115 located indoors. Compared to the transmission of smaller frequencies and longer waves using the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz, the transmission of UHF waves may be associated with smaller antennas and shorter distances (e.g., less than 100 kilometers).

[0088] The wireless communication system 100 may also operate in the super high frequency (SHF) region using a frequency band from 3 GHz to 30 GHz (also referred to as the centimeter band) or in the extremely high frequency (EHF) region of the spectrum (e.g., from 30 GHz to 300 GHz) (also referred to as the millimeter band). In some examples, the wireless communication system 100 may support millimeter wave (mmW) communication between the UE 115 and the base station 105, and the EHF antennas of the corresponding devices may be even smaller and more closely spaced compared to UHF antennas. In some examples, this may facilitate the use of antenna arrays within the device. However, the propagation of EHF transmissions may suffer even greater atmospheric attenuation and shorter distances compared to SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions using one or more different frequency regions, and the designation of the frequency bands across these frequency regions may vary according to the country or regulatory body.

[0089] The wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 may employ licensed assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed frequency band such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in an unlicensed radio frequency spectrum band, devices such as the base station 105 and the UE 115 may employ carrier sensing for collision detection and avoidance. In some examples, operation in the unlicensed frequency band may be based on carrier aggregation configurations (e.g., LAA) that combine with component carriers operating in the licensed frequency band. Operations in the unlicensed spectrum may include downlink transmissions, uplink transmissions, peer-to-peer (P2P) transmissions, or device-to-device (D2D) transmissions, etc.

[0090] The base station 105 or the UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. The antennas of the base station 105 or the UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operation or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, the antennas or antenna arrays associated with the base station 105 may be located at different geographical locations. The base station 105 may have an antenna array having a number of rows and columns of antenna ports that the base station 105 may use to support beamforming for communication with the UE 115. Similarly, the UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted via the antenna ports.

[0091] Base station 105 or UE 115 can use MIMO communication to utilize multipath signal propagation and improve spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such a technique can be referred to as spatial multiplexing. For example, a transmitting device can transmit multiple signals via different antennas or different combinations of antennas. Similarly, a receiving device can receive multiple signals via different antennas or different combinations of antennas. Each of the multiple signals can be referred to as a separate spatial stream and can carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers can be associated with different antenna ports for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) (where multiple spatial layers are transmitted to the same receiving device) and multi-user MIMO (MU-MIMO) (where multiple spatial layers are transmitted to multiple devices).

[0092] Beamforming (which can also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting device or a receiving device (e.g., base station 105, UE 115) to shape and direct an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming can be achieved by combining signals transmitted via the antenna elements of an antenna array such that some signals propagating in a particular orientation relative to the antenna array experience constructive interference while other signals experience destructive interference. The adjustment of the signals transmitted via the antenna elements can include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to the signals carried via the antenna elements associated with the device. The adjustment associated with each of the antenna elements can be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device, or relative to some other orientation).

[0093] As part of the beamforming operation, base station 105 or UE 115 can use beam scanning techniques. For example, base station 105 can use multiple antennas or an antenna array (e.g., an antenna panel) to perform beamforming operations for directional communication with UE 115. Base station 105 can transmit some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) multiple times in different directions. For example, base station 105 can transmit signals according to different sets of beamforming weights associated with different transmission directions. Transmissions in different beam directions can be used (e.g., by the transmitting device such as base station 105 or by the receiving device such as UE 115) to identify the beam direction for subsequent transmissions or receptions performed by base station 105.

[0094] Base station 105 may transmit some signals (e.g., data signals associated with a particular receiving device (e.g., UE 115)) in a single beam direction (e.g., the direction associated with a particular receiving device). In some examples, the beam direction associated with transmission along a single beam direction may be determined based on signals transmitted in one or more beam directions. For example, UE 115 may receive one or more of the signals transmitted by base station 105 in different directions and may report to base station 105 an indication of the signal received by UE 115 having the highest signal quality or otherwise acceptable signal quality.

[0095] In some examples, multiple beam directions may be used to perform transmissions by a device (e.g., by base station 105 or UE 115), and the device may use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmission (e.g., from base station 105 to UE 115). UE 115 may report feedback indicating precoding weights for one or more beam directions, and the feedback may correspond to a configured number of beams across the system bandwidth or one or more subbands. Base station 105 may transmit reference signals (e.g., cell-specific reference signal (CRS), channel state information reference signal (CSI-RS)) that may or may not be precoded. UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., multi-panel type codebook, linear combination type codebook, port selection type codebook). Although these techniques are described with reference to signals transmitted by base station 105 in one or more directions, UE 115 may employ similar techniques to transmit signals multiple times in different directions (e.g., for identifying beam directions for subsequent transmissions or receptions by UE 115) or to transmit signals in a single direction (e.g., for transmitting data to a receiving device).

[0096] A receiving device (e.g., UE 115) may attempt multiple receive configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from base station 105. For example, the receiving device may receive by receiving via different antenna sub-arrays, by processing received signals according to different antenna sub-arrays, by receiving according to different sets of receive beamforming weights (e.g., different sets of directional listening weights) applied to signals received at multiple antenna elements of the antenna array, or by processing received signals according to different sets of receive beamforming weights applied to signals received at multiple antenna elements of the antenna array (any of the above operations may be referred to as "listening" according to different receive configurations or receive directions), thereby attempting multiple receive directions. In some examples, the receiving device may use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal). The single receive configuration may be aligned in a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have the highest signal strength, the highest signal-to-noise ratio (SNR), or otherwise acceptable signal quality based on listening according to multiple beam directions).

[0097] Wireless communication system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communication at the bearer or packet data convergence protocol (PDCP) layer may be IP-based. The radio link control (RLC) layer may perform packet segmentation and reassembly for transmission over logical channels. The media access control (MAC) layer may perform priority handling and multiplexing of logical channels to transport channels. The MAC layer may also use error detection techniques, error correction techniques, or both to support retransmission at the MAC layer to improve link efficiency. In the control plane, the radio resource control (RRC) protocol layer may provide establishment, configuration, and maintenance of an RRC connection between UE 115 and base station 105 or core network 130, thereby supporting radio bearers for user plane data. At the physical layer, transport channels may be mapped to physical channels.

[0098] UE 115 and base station 105 may support retransmission of data to increase the likelihood that the data is successfully received. Hybrid Automatic Repeat reQuest (HARQ) feedback is a technique for increasing the likelihood that data is correctly received over communication link 125. HARQ may include a combination of error detection (e.g., using Cyclic Redundancy Check (CRC)), forward error correction (FEC), and retransmission (e.g., Automatic Repeat reQuest (ARQ)). HARQ can improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions). In some examples, a device may support HARQ feedback in the same time slot, where the device may provide HARQ feedback for data received in previous symbols in that time slot. In other cases, the device may provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0099] In some cases, UE 115 in wireless communication system 100 may have multiple TRPs that are spatially separated. A multi-TRP UE 115 may use Spatial Domain Multiplexing (SDM) to simultaneously transmit or receive multiple sidelink data packets (e.g., over sidelink communication link 135) from two or more TRPs. A multi-TRP UE 115 may map each data packet to a different spatial layer and may determine overlapping resources for transmitting two data packets. A multi-TRP UE may send sidelink control information (SCI) to other UEs. In some cases, the SCI may be common for two data packets. In other cases, a multi-TRP UE may send common SCI and separate SCI for each data packet. In any case, the SCI may include common and separate parameters for each spatial layer and / or data packet.

[0100] Figure 2 An example of a wireless communication system 200 that supports control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure is shown. In some examples, wireless communication system 200 may implement aspects of wireless communication system 100. Wireless communication system 200 may include multiple UEs 205, which may be examples of the UEs 115 described Figure 1 above. As Figure 2 shown, UE 205 may be an example of a vehicle.

[0101] The wireless communication system 200 may include UEs 205-a, 205-b, UE 205-c, UE 205-d, and UE 205-e. In some examples, the UEs 205 may communicate with each other (e.g., within a V2X system, a D2D system, etc.), and may employ sidelink transmissions to save power, reduce latency, and ensure reliable communication. For example, the wireless communication system 200 may support V2X communication between UE205-a and UEs 205-b, 205-c, and 205-d, and the V2X communication may include sidelink communication.

[0102] Although the access link is not depicted in the Figure 2 example, it can be understood that the wireless communication system 200 may support an access link and a sidelink for communication between one or more communication devices. The access link may refer to a communication link between a UE (such as UE 205-a, 205-b, 205-c, or 205-d) and a base station. The sidelink may refer to any communication link between similar wireless devices (e.g., a communication link between UEs, or a backhaul communication link between base stations). Note that although the various examples provided herein are discussed with respect to UE sidelink devices, such sidelink technologies may be used for any type of wireless device that uses sidelink communication. For example, the sidelink may support one or more of D2D communication, V2X or V2V communication, message relaying, discovery signaling, beacon signaling, or other signals sent from one UE to one or more other UEs over the air.

[0103] UE 205-a may be a multi-TRP UE that includes TRPs 210-a-1 and 210-a-2. In some aspects, each of TRPs 210-a-1 and 210-a-2 may be configured to receive and transmit signals. TRPs 210-a-1 and 210-a-2 may be configured to transmit signals in combination with each other, individually (e.g., separately from each other), or both. In this regard, the TRPs 210 may include, but are not limited to, antennas, antenna panels, etc. In some examples, a device that supports sidelink communication (e.g., a vehicle) may include a front antenna panel and a rear antenna panel. Subsequently, larger vehicles (such as trucks and trailers) may include multiple TRPs. In such a case, each TRP of the multi-TRP UE may be associated with one or more TCI states, and the TCI state may be indicated in transmissions from the TRP.

[0104] In some cases, the TRPs 210 of the UE 205-a can be placed close to each other (e.g., near). In other cases, the TRPs 210 of the UE 205-a can be physically separated from each other by a certain distance. For example, the TRP 210-a-1 can be placed near the front of the vehicle, and the TRP 210-a-2 can be placed at or near the rear of the vehicle. In this example, the TRP 210-a-1 (e.g., including the first antenna panel) and the TRP 210-a-2 (e.g., including the second antenna panel) can be separated from each other by several meters. In the case of a larger vehicle such as a semi-truck, this physical separation may even be greater, where multiple TRPs 210 of the UE 205-a can be physically separated from each other by twenty meters or more.

[0105] The TRPs 210 on the same vehicle can be different radio frequency (RF) modules with shared hardware, shared software controllers, or a combination of both. Due to the TRP separation, the TRPs 210 on the same vehicle may view the communication channel in different ways. Due to factors such as the use of line-of-sight (LoS) channels versus non-line-of-sight (NLoS) channels, blockages, etc., the spatial separation of the TRPs may introduce differences in how different TRPs view the channel. The LoS channel may be different from the NLoS channel. A first vehicle can use the LoS channel to directly send a message to a second vehicle. In Figure 2 the example of, the UE 205-d uses the LoS channel to transmit from the TRP 210-d to the TRP 210-a-2 of the UE 205-a via the communication link 210-d-2. Alternatively, a first vehicle can use the NLoS channel, which may depend on reflections from surrounding objects, to send a signal to a second vehicle. As shown, the UE 205-d uses the NLoS channel to transmit from the TRP 210-d to the TRP 210-a-1 of the UE 205-a via the communication link 215-d-1. This NLoS channel relies on the communication link 215-d-1 to reflect on the object 220 to complete the transmission path.

[0106] In some cases, due to an obstacle (e.g., another vehicle) on the LoS channel, the UE 205-b can use the NLoS channel instead of the LoS channel. For example, as Figure 2As shown, UE 205-b experiences a blockage caused by UE 205-e in the path of LoS communication link 215-b-2. Thus, UE 205-b uses the NLoS channel to transmit from TRP 210-b to TRP 210-a-1 of UE 205-a via communication link 215-b-1, where the NLoS channel relies on reflections from object 220 to reach TRP 210-a-1. In some examples, the NLoS channel may correspond to a transmission path length different from that of the LoS channel, resulting in propagation loss along the NLoS channel. Thus, UE 205-a is able to utilize spatial domain multiplexing (SDM) to counteract the channel differences. UE 205-a is able to simultaneously and directionally transmit or receive multiple data packets, resulting in more efficient and robust communication.

[0107] Additionally or alternatively, UE 205-a may experience a change in channel conditions due to the spatial separation of the TRPs. For example, TRP 210-a-1 may receive a signal from UE 205-b via communication link 215-b-1, and TRP 210-b-2 may receive a signal from UE 205-d via communication link 215-d-2. In this example, the signal received at TRP 210-a-1 may have traveled a greater distance compared to the signal received at TRP 210-a-2. The varying propagation distance may result in varying parameters (e.g., characteristics) associated with the signals received by the respective TRPs 210. For example, due to the difference in propagation distance, the signal received at TRP 210-a-1 may exhibit lower signal quality (e.g., lower reference signal received power, lower reference signal received quality, higher signal-to-noise ratio, higher signal-to-interference-plus-noise ratio) compared to the signal received at TRP 210-a-2. Additionally, the signal received at TRP 210-a-1 may be received later in time compared to the signal received at TRP 210-a-2. These differences in signal parameters (e.g., reference signal received power, reference signal received quality, signal-to-noise ratio, signal-to-interference-plus-noise ratio, reception time) may occur even though the respective signals are actually transmitted by UE 205-b and UE 205-d at the same time and with the same transmit power.

[0108] In some cases, different TRPs 210 of the UE 205-a may include different numbers of other wireless devices to which they are connected (e.g., more traffic in front of the vehicle may result in the front TRP 210 having more wireless connections compared to the rear TRP 210). Additionally, radio conditions and physical obstacles may cause one TRP 210 to have a lower quality link quality compared to another TRP 210. In some cases, the UE 205-a may send transmissions of the same packet from different TRPs 210. Each transmission may be associated with one or more transmission configuration indicator (TCI) states. The UE 205-a may reserve transmission resources for future transmissions by signaling sidelink control information. Multi-TRP sidelink communication may enhance the coverage for communication between the UE 205-a and other UEs. Additionally, multiple TRPs 210 may improve reliability, coverage, and capacity performance through flexible deployment scenarios. More specifically, multiple TRPs 210 equipped in different components of the vehicle may improve the reliability of safety and other applications that require high robustness. In some cases, from a transmission perspective, data coverage may be biased. For example, side coverage may not be important for certain cases (e.g., a TRP located on the side of the vehicle may not provide much value), and the forward or backward or 360-degree coverage around the vehicle may depend on the packet content or type. From a receiver perspective, multiple TRPs 210 at the vehicle may desire 360-degree coverage. Therefore, the UE 205-a may use two TRPs 210 to receive packets from other UEs 205.

[0109] As shown in the figure, UE 205-a may include TRP 210-a-1 at the front of the vehicle and TRP 210-a-2 at the rear of the vehicle. Thus, UE 205-a may receive packets from UE 205-b and UE 205-c via TRP 210-a-1, and may receive packets from UE 205-c and UE 205-d via TRP 210-a-2. Using each TRP 210, UE 205-a may establish corresponding communication links with each sending UE 205. For example, UE 205-a may establish a first communication link 215-b-1 with UE 205-b via TRP 210-a-1 and TRP 210-b, a second communication link 215-c-2 with UE 205-c via TRP 210-a-1 and TRP 210-c, and a third communication link 215-d-1 with UE 205-d via TRP 210-a-1 and TRP 210-d. Similarly, UE 205-a may establish a fourth communication link 215-c-1 with UE 205-c via TRP 210-a-2 and TRP 210-c, and a fifth communication link 215-d-2 with UE 205-d via TRP 210-a-2 and TRP 210-d. As Figure 2 shown, UE 205-b may attempt an additional communication link 215-b-2 with TRP 210-a-2 of UE 205-a, but the channel may be blocked by UE 205-e.

[0110] As described herein, to effectively use sidelink resources (e.g., time and frequency resources allocated for sidelink communication), UE 205 may use spatial domain multiplexing (SDM) to send or receive simultaneous transmissions. For example, UE 205 may use SDM for transmissions with different direction requirements. In some cases, UE 205 may use SDM for the directional retransmission of broadcast messages. For example, UE 205-a may receive a negative acknowledgment (NACK) for a first packet from a first direction and a NACK for a second packet from a second direction. UE 205-a may simultaneously retransmit the first data packet in the first direction and the second data packet in the second direction. In some cases, UE 205 may use SDM for directional transmissions indicated by the application layer. For example, an application generating a packet may require the packet to be sent in a specific direction. The directional requirement may be based on network configuration, etc. As described herein, enhancements to control information and resource determination for sidelink communication may enable multi-TRP UEs to simultaneously send and receive multiple packets via SDM.

[0111] For example, UE 205-a may use SDM to simultaneously send two or more data packets of a sidelink transmission to UE 205-d via both TRP 210-a-1 and 210-a-2 over a sidelink communication link. Additionally or alternatively, UE 205-a may use SDM to simultaneously send a first data packet to UE 205-c via TRP 210-a-1 and a second data packet to UE 205-d via TRP 210-a-2. In either case, the data packets may be sent on the same or overlapping sets of time and frequency resources. To enable such SDM transmissions, UE 205-a may send sidelink control information (SCI) to UE 205-c and / or UE 205-d. The SCI may include an indication of SDM between the first and second (or more) spatial layers of the sidelink transmission. Additionally, the SCI may indicate the set of resources to be used for the sidelink transmission. The set of resources may be determined based on the signal strength of each TRP, the size of one or more of the data packets in the data packet, or other parameters. Thus, UE 205-a may send the first data packet of the two or more data packets from TRP 210-a-1 on the first spatial layer, and send the second data packet of the two or more data packets from TRP 210-b-2 on the second spatial layer. In some examples, UE 205-a may also include an indication of the HARQ process identifier (ID) to be used for each spatial layer (e.g., in the SDM indication, SCI, etc.).

[0112] In some examples, UE 205-a may send multiple phases of SCI to schedule simultaneous or overlapping data transmissions from TRP 210-a-1 and TRP 210-a-2. The SCI phases may include shared SCI (e.g., SCI associated with both the data packet and / or the spatial layer), individual SCI (e.g., individual SCI associated with the respective data packet and / or spatial layer), or both. For example, UE 205-a may use a first phase of SCI (e.g., SCI-1) to indicate SCI shared between two data packets and / or spatial layers, and may use two second phases of SCI (e.g., SCI-2) for each of the data packet and / or spatial layer, respectively. The shared SCI-1 may include an indication of the common MCS for the two spatial layers, the reservation priority for the two spatial layers, etc. The SCI-2 for each spatial layer may include an individual reservation priority, an individual MCS, a broadcast type, a destination identifier, a communication range indicator, or a DMRS port, etc., for each respective layer.

[0113] A receiving UE (e.g., UE 205-b, UE 205-c, or UE 205-d) can use the SCI to determine whether the receiving UE is to decode one or both of the SDM transmissions. The SCI can be used by the receiving UE to decode one or more data packets in the spatially multiplexed data packets. Determining whether the receiving UE is to decode a transmission can be based on identifying the HARQ process ID and the source and destination IDs as provided in the SCI. For example, if the receiving UE identifies the HARQ process ID, source ID, or destination ID associated with it, the receiving UE can decode the transmission corresponding to that ID. The receiving UE can ignore all transmissions specified by IDs not corresponding to the receiving UE.

[0114] Figure 3 FIG. 300 illustrates an example of a communication scheme that supports control information for sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure. In some examples, communication scheme 300 may implement aspects of wireless communication system 100 or wireless communication system 200. Communication scheme 300 may include a UE 305 having multiple TRPs 310, and UE 305 may be an example of UE 115 or UE 205 as described with reference to Figure 1 and 2 FIGs. In some examples, communication scheme 300 may implement aspects of wireless communication system 100 or wireless communication system 200. Communication scheme 300 may include a UE 305 having multiple TRPs 310, and UE 305 may be an example of UE 115 or UE 205 as described with reference to FIGS.

[0115] UE 305 may include a first TRP 305-a and a second TRP 305-b different from the first TRP 305-a. TRPs 305-a and 305-b may be configured to transmit signals in combination with each other, transmit signals separately (e.g., apart from each other), or perform both operations. In this regard, TRP 305 may include, but is not limited to, antennas, antenna panels, etc. As depicted herein, UE 305 may support techniques for sidelink SDM transmissions from multiple TRPs. In particular, the multi-TRP UE 305 may configure SCI transmissions to indicate SDM between two or more spatial layers of a sidelink transmission. In some examples, the sidelink control information transmission may also reserve resources for the sidelink transmission. In some examples, the sidelink control information transmission may include an indication of a set of resources for the sidelink transmission, and other parameters corresponding to one or more of the spatial layers.

[0116] As shown in the figure, the UE 305 may send a sidelink transmission including a common SCI 320, a first data packet 315-a, and a second data packet 315-b. Each data packet may be sent on a subchannel 325 and within a resource set 330. For example, at time t1, the UE 305 may send the common SCI 320 from both the TRP 310-a and 310-b on subchannels 325-a and 325-b respectively. The UE 305 may send the first data packet 315-a from the TRP 310-a on subchannel 325-a using the resource set 330-a. At the same time, the UE 305 may send the second data packet 315-b from the TRP 310-b on subchannel 325-b using the resource set 330-b. In some cases, the data packets 315 may be the same (e.g., may have the same payload), while in other cases, the data packets 315 may be different.

[0117] When preparing for an SDM sidelink transmission, the UE 305 may determine the resources 330 and use the common SCI 320 to signal the simultaneous transmission and the determined resources. Each TRP 310 may maintain a separate resource map, and the UE 305 may consider each resource map to jointly select the TTI and the resources 330. The UE 305 may consider resource availability and timing deadlines when determining the resources 330. For example, the UE 305 may determine the resources 330 that are available for the two data packets 315 and support the timing constraints of each data packet 315. In some examples, the resources 330 may be selected such that they are on the same TTI and / or subframe. As Figure 3 shown, the resources 330 are on the same TTI because they are sent between time t1 and time t2.

[0118] The UE 305 may determine the resources 330 considering the size differences of each data packet 315. For example, if the data packet 315-a has a larger size compared to the data packet 315-b, the UE 305 may select the resources that can accommodate the packet 315-a. Additionally or alternatively, the UE 305 may select the resources 330 based on the MCS of one or both of the data packets 315. For example, the data packet 315-a may be larger than the data packet 315-b, and the data packet 315-a may be encoded using a higher MCS. The UE 305 may increase the MCS of the data packet 315-a (e.g., up to a threshold) to fit the larger data packet 315-a within the available resources. However, if the UE 305 determines that increasing the MCS may not enable the data packet 315-a to fit within the available resources, the UE 305 may not perform SDM on the data packet 315.

[0119] The UE 305 may map simultaneous SDM transmissions to different spatial layers. For example, the UE 305 may map a first data packet 315-a to layer 1 and a second data packet 315-b to layer 2. The mapped transmissions may correspond to different application data, destinations, etc. In some examples, the UE 305 may select reference signals for each spatial layer such that the reference signals may be decoded orthogonally. In some examples, the data packets 315 may be sent as hierarchical transmissions.

[0120] In some examples, in the common SCI 320, the UE 305 may include an indication of SDM between spatial layers. In some cases, depending on using the shared first phase of the SCI (e.g., SCI-1) for spatial layers and the separate second phase of the SCI (e.g., SCI-2) for individual spatial layers, the indication of SDM between spatial layers may be implicit. In such cases, SCI-1 and SCI-2 may each carry information for the two data packets 315, and the information may be applied to the two data packets 315 or applied separately to each respective data packet 315. For example, SCI-1 may include information shared between two spatial layers, and the first SCI-2 may include information for the first spatial layer, and the second SCI-2 may contain information for the second spatial layer. In some cases, SCI-2 may indicate the rank of the data packet 315 associated with the corresponding spatial layer. In some cases, SCI-2 may indicate whether two SDM transmissions are mapped to the same data packet 315 or are mapped to different data packets 315. For example, the UE 305 may assign a HARQ process ID to each spatial layer, and the SCI-2 for each spatial layer may include an indication of the corresponding HARQ process ID.

[0121] The UE 305 can determine the MCS for each spatial layer for transmitting the data packet 315. In some examples, the UE 305 can assign the MCS to each spatial layer individually, while in other examples, the UE 305 can assign a common MCS that is shared between two spatial layers. In any case, the MCS for the spatial layer can be used to encode the data packet 315 mapped to the corresponding spatial layer. The MCS for each layer can be indicated in SCI-1, SCI-2, or both. For example, if the MCS is shared (e.g., is common) for two spatial layers (e.g., and two corresponding data packets 315-a and 315-b), the UE 305 can indicate the common MCS in SCI-1. Alternatively, if each spatial layer (e.g., and each data packet 315) is assigned a separate MCS, the UE 305 can indicate each separate MCS in SCI-1. As another example, the UE 305 can use the assigned corresponding MCS to send a separate SCI-2 for each corresponding spatial layer. Alternatively, the UE 305 can send an indication of the common MCS in SCI-1, where the common MCS will be used to transmit and decode the corresponding separate SCI-2, but each SCI-2 can also indicate a separate (e.g., different from the common) MCS for each corresponding data packet 315.

[0122] The UE 305 may determine an appropriate MCS based on the size of each data packet 315 (e.g., relative to the determined set of resources 330) or the size of the subchannel 325 available for SDM transmission. For example, if the UE 305 determines that sufficient resources are available, the UE 305 may select the lowest MCS associated with the data packet 315. If the UE 305 determines that there are not enough available resources, the UE 305 may select an MCS based on the size of the subchannel 325. The UE 305 may select a reserved size for SDM transmission such that the larger of the two data packets 315 can be accommodated. In some examples, when multiple MCSs can be used for SDM transmission, resources that are suitable for the smaller data packet 315 but not for the larger data packet 315 may be available. In such a case, the UE 305 may utilize a higher MCS to encode the larger data packet 315 and may indicate the corresponding MCS (e.g., in SCI-2). In some examples, the UE 305 may determine to send a first data packet 315 on a first TRP 310 (e.g., TRP 310-a). The UE 305 may increase the resource exclusion reference signal received power (RSRP) threshold until a preconfigured limit is reached, such that the second data packet 315 can be sent on a second TRP 310 (e.g., TRP 310-b). The preconfigured limit may be set to mitigate transmission interference. If the UE 305 determines that the two data packets 315 cannot be spatially multiplexed based on RSRP measurements, the UE 305 may send the packets separately.

[0123] In some examples, in the common SCI 320 (e.g., SCI-1), the UE 305 may include one or more bits of DMRS port indication to indicate one or more ports corresponding to each spatial layer. For example, the UE 305 may use one-bit DMRS and may limit the use of two ports on the TRP 310. Alternatively, the UE 305 may use a multi-bit indication to indicate the DMRS ports, such as a 3-bit indication (e.g., to signal 8 possible combinations of DMRS ports). The UE 305 may also indicate (e.g., in SCI-2) one or more DMRS ports corresponding to each TRP.

[0124] The UE 305 may include an indication of the priority level for each data packet 315. Each data packet 315 may have a different or the same priority level. In some examples, the UE 305 may perform SDM transmission on data packets 315 having the same priority level. In other cases, if the data packets 315 each have a different priority level, the UE 305 may include (e.g., in SCI-1) an indication of the highest priority level of the data packets 315. For example, if data packet 315-a has a priority level of 1 (e.g., a higher priority level) and data packet 315-b has a priority level of 0 (e.g., a lower priority level), the common SCI 320 (e.g., SCI-1) may indicate that the SDM transmission has a priority level of 1. In some other cases, the UE 305 may indicate (e.g., in SCI-1) the corresponding priority level for each data packet 315.

[0125] In some cases, the SCI (e.g., the common SCI 320) may include resource information for the current data packet (e.g., data packet 315) and resource reservation information for future transmissions (such as retransmissions of the current data packet). In such a case, the UE 305 may include resource reservation information according to the priority level. For example, at a later time (e.g., after time t2), SDM may be used to retransmit data packet 315. The SCI-1 included in the common SCI 320 transmitted at time t1 may include resource reservation for future retransmissions and an indication of the highest available priority of data packet 315. Alternatively, if data packet 315 is to be retransmitted individually (e.g., without using SDM) at a later time (e.g., after time t2), the SCI-1 included in the common SCI 320 may include resource reservation for the retransmission of each individual data packet 315 and an indication of the priority associated with each data packet 315.

[0126] In some examples, in a common SCI 320 (e.g., SCI-1), the UE 305 may indicate a transmission destination ID for each spatial layer. For example, when using unicast or a mix of unicast, broadcast, or multicast links, the UE 305 may include a list of destination IDs associated with each spatial layer. Additionally or alternatively, the UE 305 may include an indication of the broadcast type for each data packet 315 (e.g., in an SCI-2 of one or more values). The broadcast type may indicate whether the data packet 315-a is a broadcast transmission, unicast transmission, multicast transmission, or some combination thereof. For example, the common SCI 320 may include a multicast broadcast type indication for the data packet 315-a, which indicates that the data packet 315-a is for a group to which the receiving UE does not belong, and the receiving UE may choose to avoid decoding the data packet 315-a. In some examples, if the data packet 315 is not a retransmission, the UE 305 may (e.g., in the SCI-2) include a new data indicator (e.g., a set of new data indicator bits) associated with the corresponding spatial layer. In some examples, the UE 305 may signal a set of one or more communication ranges for each data packet 315 such that the range of a given transmission channel must meet a threshold value for each data packet 315 to be sent. For example, if the SDM transmission includes a mix of broadcast and multicast transmissions, the multicast transmission may have a communication range requirement, but the broadcast transmission may not.

[0127] A receiving UE may receive the common SCI 320 associated with the SDM transmission on a sidelink channel. The common control information may be used by the receiving UE to decode one or all of the array packets in the multiplexed data packets 315. Determining whether the receiving UE should decode the transmission may be based on identifying the HARQ process ID, destination ID, communication range indicator, and broadcast type as provided in the common SCI 320. If the receiving UE identifies the HARQ process ID, destination ID, or other parameter associated with it, the receiving UE may decode the data packet 315 corresponding to that ID. The receiving UE may ignore all transmissions specified by IDs not corresponding to the receiving UE.

[0128] Figures 4A to 4C Examples of communication schemes supporting the communication of control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure are shown. In some examples, the communication schemes 401, 402, and 403 may implement aspects of the wireless communication systems 100, 200, or 300. For example, the communication schemes 401, 402, and 403 may be examples of communication schemes for sending SDM sidelink transmissions between multi-TRP UEs, as Figure 2 and 3 described in.

[0129] As described herein, a multi-TRP UE may use SDM for sidelink communication to simultaneously transmit or receive an SCI and two or more data packets. In some examples of sidelink communication, the TRP may reserve resources for upcoming transmissions via the SCI. For example, a transmitter UE may include one or more SCIs for reserving resources for future retransmissions and an SCI for the current packet (to be used by the receiver for decoding the packet). The receiver UE may determine that the SCI reserves time and frequency resources for future sidelink data transmissions. In some cases, the transmitting UE may reserve resources for SDM retransmissions of a set of data packets transmitted by a previous SDM. In some examples, the transmitting UE may reserve future resources for each data packet being transmitted (e.g., if SDM transmission is not possible for retransmission). In some examples, if SDM is possible at a later time, the transmitting UE may reserve future resources for two non-SDM transmissions.

[0130] Figure 4A Includes an SCI 405-a and two data packets 410-a and 415-a that may be transmitted using SDM. For example, as described herein, a multi-TRP UE may determine that packets 410-a and 415-a may be transmitted using SDM from two TRPs of the multi-TRP UE. The SCI 405-a may be transmitted at time t0 and may include a reservation indication for reserving resources for future transmissions. As shown, the SCI 405-a may reserve resources for a second SCI 405-b transmission and a second set of packets 410-b and 415-b that may be transmitted at time t1. Each of time t0 and t1 may be an example of the start time of a transmission time interval (TTI). Thus, the SCI 405-a may indicate a reservation for a set of future SDM transmissions.

[0131] Figure 4B Includes an SCI 405-a and two data packets 410-a and 415-a that may be transmitted using SDM from two TRPs of a multi-TRP UE. The SCI 405-a may be transmitted at a TTI starting at time t0 and may include a reservation indication for reserving resources for future transmissions. Contrary to Figure 4A Instead, Figure 4B the SCI 405-a in Figure 4BIn the example of, the multi-TRP UE can use SDM to send the first instance of SCI 405-a and packets 410-a and 415-a, but it can be determined that future retransmissions of packets 410-a and 415-a may not be able to utilize SDM. For example, the UE can determine that at time t0, data packet 410-a and data packet 415-a can each have different direction requirements and can be candidates for SDM transmission. However, based on the sensing information, the UE can determine that simultaneously retransmitting data packets 410 and 415 may result in performance degradation (e.g., due to network congestion, increased interference, latency constraints, etc.). Therefore, the UE can use SCI 405-a to reserve resources for future individual retransmissions of data packets 410 and 415. The UE can send a retransmission of data packet 410 (e.g., data packet 410-b) and SCI 405-b at time t1 based on the resource reservation indicated in SCI 405-a, and can send a retransmission of data packet 415 (e.g., data packet 415-b) and SCI 405-c at time t2.

[0132] Figure 4C Including SCI 405-a and packet 410-a sent at time t0 and SCI 405-b and data packet 415-a sent at time t1. As shown, SCI 405-a and 405-b can reserve resources for future SDM transmissions. For example, the UE can determine that individual transmissions of data packets 410 and 415 can be candidates for SDM transmission at time t2. Therefore, each individual SCI 405-a and 405-b can reserve the same resources for a single future SDM transmission that can include SCI 405-c and for the SDM transmission of data packets 410-b and 415-b.

[0133] Figure 5 An example of a process flow 500 that supports control information for sidelink spatial domain multiplexing from multiple TRPs according to aspects of the present disclosure is shown. In some examples, process flow 500 can implement aspects of wireless communication system 100 or 200 or any combination thereof. For example, process flow 500 can show that a first UE 115-a including two or more TRPs uses SDM to send common sidelink control information and one or more data packets to a second UE 115-b and a third UE 115-c.

[0134] In some cases, process flow 500 can include a first UE 115-a, a second UE 115-b, and a third UE 115-c, which can be examples of corresponding devices as described herein. Figure 5 The UE 115 shown in can be respectively referred to Figure 2 and3 Examples of the described vehicle UEs 205 and 305. In some aspects, Figure 5 the corresponding UEs 115 shown in may communicate with each other via sidelink communication links (such as Figure 2 the communication link 215 shown in).

[0135] In some examples, the operations shown in process flow 500 may be performed by hardware (e.g., including circuits, processing blocks, logic components, and other components), code executed by a processor (e.g., software or firmware), or any combination thereof. Alternative examples may be implemented, where some steps are performed in a different order than described or not at all. In some cases, steps may include additional features not mentioned below, or additional steps may be added.

[0136] At 505, UE 115-a may determine two or more data packets that two or more TRPs of UE 115-a may send using SDM. UE 115-a may determine that the data packets are candidates for sidelink SDM transmission. For example, the data packets may have different directional requirements. As an example, UE 115-a may determine that the data packets are directed retransmissions (e.g., of a broadcast transmission) or transmissions indicated as directed by the application layer (e.g., in cases where the application generating the packet has directional requirements). UE 115-a may determine that a first TRP may be used to send a first data packet and a second TRP may be used to send a second data packet. In some examples, the data packets may include the same payload, while in other examples, each data packet may have a unique payload. UE 115-a may assign each determined data packet to a spatial layer of the sidelink transmission. For example, the first data packet may be mapped to a first spatial layer of the sidelink transmission, and the second data packet may be mapped to a second spatial layer of the sidelink transmission.

[0137] At 510, UE 115-a may assign a hybrid automatic repeat request (HARQ) process identifier to each spatial layer.

[0138] At 515, UE 115-a may assign a modulation and coding scheme (MCS) to each spatial layer. In some cases, UE 115-a may assign a common MCS such that each spatial layer shares the same MCS. The common MCS may be assigned based on the size of each data packet (e.g., relative to a determined resource set for each packet). Additionally or alternatively, the common MCS may correspond to the subchannel size available for sidelink transmission. In other cases, UE 115-a may assign a separate MCS to each spatial layer such that each data packet corresponding to the spatial layer can be decoded using the corresponding MCS. For example, UE 115-a may assign a first MCS to the first layer for the first data packet and a second MCS to the second layer for the second data packet. In some examples, the separate MCS may be assigned based on the size of each data packet (e.g., relative to a determined resource set for each packet).

[0139] At 520, UE 115-a may assign additional parameters to one or more of the data packet and / or the corresponding spatial layer. Such additional parameters may include, but are not limited to, demodulation reference signal (DMRS) ports, reservation priorities, destination identifiers, broadcast types, new data indicators, communication range indicators, etc. For example, UE 115-a may assign different DMRS ports to each spatial layer. Similarly, UE 115-a may assign separate destination identifiers, broadcast types, new data indicators, and / or communication range indicators to the first spatial layer and the second spatial layer. Additionally or alternatively, UE 115-a may determine the reservation priority individually and assign it to each spatial layer, or may assign a shared reservation priority to the two spatial layers.

[0140] At 525, UE 115-a may determine a resource set for sidelink transmission. The resource set may be determined based on the measured signal strength associated with each TRP used for transmitting the sidelink transmission. In some examples, the resource set may include the same transmission time interval (TTI) for both the first TRP and the second TRP. UE 115-a may select the reservation size of the resource set based on the maximum data packet. In some cases, UE 115-a may adjust the resource exclusion signal strength threshold to enable transmission of the first spatial layer at the first TRP and transmission of the second spatial layer at the second TRP.

[0141] At 530, UE 115-a may send an SCI to UE 115-b. At 535, UE 115-a may send an SCI to UE 115-c. The SCI may include an indication of using SDM for the first and second spatial layers of the sidelink transmission. In some cases, the SDM indication may include a first phase of the SCI (e.g., SCI-1) and one or more second phases of the SCI (e.g., SCI-2). For example, the SDM indication may include a shared SCI-1 for two spatial layers and separate SCI-2s for each respective spatial layer.

[0142] The SDM indication and / or the SCI may also include one or more additional indications, such as an indication of a parameter assigned at any one of 510 to 520. The additional indications may be provided separately for each spatial layer or may be shared between the two spatial layers. For example, the SDM indication may include an indication of a first HARQ process identifier for the first spatial layer and an indication of a second HARQ process identifier for the second spatial layer. Additionally or alternatively, the SCI may signal different DMRS ports, destination identifiers, broadcast types, new data indicators, communication range indicators, or other examples for each spatial layer. In some cases, the SCI may indicate a shared reservation priority for two spatial layers or may indicate separate reservation priorities for each spatial layer.

[0143] In some examples, the shared additional indication may be signaled through the shared first phase of the SCI, and the separate additional indication may be signaled through the separate second phase of the SCI. For example, if UE 115-a determines at 515 that the spatial layers may share a common MCS, SCI-1 may indicate the common MCS. Alternatively, if UE 115-a determines that separate MCSs may be assigned to each spatial layer, the SCI-2s for each respective spatial layer may indicate the corresponding assigned MCSs. In other examples, UE 115-a may include separate additional indications for each spatial layer in the shared first phase of the SCI. For example, SCI-1 may include an indication of a separate MCS for each of the first and second spatial layers.

[0144] In some cases, the corresponding assigned MCS can be used to transmit the SCI-2 for each respective spatial layer. Additionally or alternatively, UE 115a can transmit a shared SCI-1 that includes an indication of a common MCS to be used to decode the individual SCI-2s, where the SCI-2s can be transmitted using the common MCS. In this case, each SCI-2 can also include an indication of an individual MCS to be used to decode each data packet. For example, the SCI-2 for the first spatial layer can include an indication of a first MCS to be used to decode the first data packet, and the SCI-2 for the second spatial layer can include an indication of a second MCS to be used to decode the second data packet.

[0145] At 540, UE 115-b can assign a first HARQ process identifier to the first spatial layer (e.g., indicated in the SCI received at 530), and assign a second HARQ process identifier to the second spatial layer (e.g., indicated in the SCI received at 530). The HARQ process identifier can be assigned by UE 115-b based on the SDM indication received at 530.

[0146] At 545, UE 115-c can assign a first HARQ process identifier to the first spatial layer (e.g., indicated in the SCI received at 535), and assign a second HARQ process identifier to the second spatial layer (e.g., indicated in the SCI received at 535). The HARQ process identifier can be assigned by UE 115-c based on the SDM indication received at 535.

[0147] At 550, UE 115-b can determine the MCS for each spatial layer based on the indication received in the SCI at 530. For example, based on the SCI, UE 115-b can determine that the two spatial layers can be decoded using a shared MCS, or that each spatial layer can be decoded using a separate respective MCS.

[0148] At 555, UE 115-c can determine the MCS for each spatial layer based on the indication received in the SCI at 535. For example, based on the SCI, UE 115-c can determine that the two spatial layers can be decoded using a shared MCS, or that each spatial layer can be decoded using a separate respective MCS.

[0149] At 560, UE 115-b may determine additional parameters corresponding to each spatial layer. The additional parameters may be determined based on additional indications received at 530. For example, UE 115-b may determine DMRS ports, reservation priorities, destination identifiers, broadcast types, new data indicators, communication range indicators, or any other parameters for each spatial layer. In some examples, one or more parameters determined at 545 may be shared between two spatial layers.

[0150] At 565, UE 115-c may determine additional parameters corresponding to each spatial layer. The additional parameters may be determined based on additional indications received at 535. For example, UE 115-c may determine DMRS ports, reservation priorities, destination identifiers, broadcast types, new data indicators, communication range indicators, or any other parameters for each spatial layer. In some examples, one or more parameters determined at 565 may be shared between two spatial layers.

[0151] At 570, UE 115-a may use a resource set (e.g., determined at 525) to transmit a first data packet on a first spatial layer, and UE 115-b may use the resource set (e.g., determined at 525) to receive the first data packet on the first spatial layer. UE 115-a may use SDM to transmit the first data packet from a first TRP on the first spatial layer.

[0152] At 575, UE 115-a may use a resource set (e.g., determined at 525) to transmit a second data packet on a second spatial layer, and UE 115-c may use the resource set (e.g., determined at 525) to receive the second data packet on the second spatial layer. UE 115-a may use SDM to transmit the second data packet from a second TRP on the second spatial layer.

[0153] Figure 6 Block diagram 600 shows a device 605 that supports control information for sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure. Device 605 may be an example of aspects of UE 115 as described herein. Device 605 may include a receiver 610, a transmitter 615, and a communication manager 620. Device 605 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0154] The receiver 610 can provide a unit for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to control information for sidelink spatial domain multiplexing from multiple TRPs). The information can be passed to other components of the device 605. The receiver 610 can utilize a single antenna or an array of multiple antennas.

[0155] The transmitter 615 can provide a unit for transmitting signals generated by other components of the device 605. For example, the transmitter 615 can transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to control information for sidelink spatial domain multiplexing from multiple TRPs). In some examples, the transmitter 615 can be co-located with the receiver 610 in a transceiver module. The transmitter 615 can utilize a single antenna or an array of multiple antennas.

[0156] The communication manager 620, the receiver 610, the transmitter 615, or various combinations or various components thereof can be examples of units for performing various aspects of the control information for sidelink spatial domain multiplexing from multiple TRPs as described herein. For example, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof can support methods for performing one or more of the functions described herein.

[0157] In some examples, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof can be implemented in hardware (e.g., with communication management circuitry). The hardware can include a processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured to or otherwise supporting the units for performing the functions described in this disclosure. In some examples, the processor and the memory coupled to the processor can be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0158] Additionally or alternatively, in some examples, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented with code executed by a processor (e.g., as communication management software or firmware). If implemented with code executed by a processor, the functions of the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a central processing unit (CPU), an ASIC, an FPGA, or any combination of these or other programmable logic devices (e.g., configured or otherwise supporting units for performing the functions described in this disclosure).

[0159] In some examples, the communication manager 620 may be configured to use the receiver 610, the transmitter 615, or both, or otherwise cooperate with the receiver 610, the transmitter 615, or both, to perform various operations (e.g., receive, monitor, transmit). For example, the communication manager 620 may receive information from the receiver 610, send information to the transmitter 615, or integrate with the receiver 610, the transmitter 615, or both to receive information, send information, or perform various other operations as described herein.

[0160] According to examples disclosed herein, the communication manager 620 may support wireless communication at the UE. For example, the communication manager 620 may be configured or otherwise support a unit for transmitting sidelink control information, the sidelink control information signaling a set of resources and the number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. The communication manager 620 may be configured or otherwise support a unit for transmitting a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing. The communication manager 620 may be configured or otherwise support a unit for transmitting a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0161] Additionally or alternatively, according to examples as disclosed herein, the communication manager 620 may support wireless communication at a UE. For example, the communication manager 620 may be configured to or otherwise support a unit for receiving sidelink control information that signals a set of resources and the number of spatial layers for sidelink transmission, where the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. The communication manager 620 may be configured to or otherwise support a unit for receiving a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing. The communication manager 620 may be configured to or otherwise support a unit for receiving a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0162] By including or configuring the communication manager 620 according to examples as described herein, a device 605 (e.g., a processor that controls or is otherwise coupled to the receiver 610, transmitter 615, communication manager 620, or a combination thereof) may support more efficient sidelink transmissions from multiple TRPs. For example, by providing control information that enables simultaneous SDM sidelink transmissions, the number of sidelink transmissions and retransmissions may be reduced, thereby reducing network overhead and improving efficiency. Additionally, implementing SDM sidelink transmissions according to the techniques described herein may reduce the frequency at which the processor of a multi-TRP UE 115 must be boosted to handle signal transmissions or retransmissions and receptions, thereby reducing processing resources at the multi-TRP UE 115 and the receiver UE 115, reducing power consumption, and improving battery performance.

[0163] Figure 7 FIG. 700 is a block diagram illustrating a device 705 that supports control information for sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure. The device 705 may be an example of aspects of the device 605 or UE 115 as described herein. The device 705 may include a receiver 710, a transmitter 715, and a communication manager 720. The device 705 may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0164] The receiver 710 may provide a unit for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., a control channel, a data channel, an information channel associated with control information for sidelink spatial domain multiplexing from multiple TRPs). The information may be passed to other components of the device 705. The receiver 710 may utilize a single antenna or an array of multiple antennas.

[0165] The transmitter 715 can provide a unit for transmitting signals generated by other components of the device 705. For example, the transmitter 715 can transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to control information for sidelink spatial domain multiplexing from multiple TRPs). In some examples, the transmitter 715 can be co-located with the receiver 710 in a transceiver module. The transmitter 715 can utilize a single antenna or an array of multiple antennas.

[0166] The device 705 or its various components can be examples of units for performing various aspects of control information for sidelink spatial domain multiplexing from multiple TRPs as described herein. For example, the communication manager 720 can include a sidelink control information transmitter 725, a data transmitter 730, a sidelink control information receiver 735, a data receiver 740, or any combination thereof. The communication manager 720 can be an example of aspects of the communication manager 620 as described herein. In some examples, the communication manager 720 or its various components can be configured to perform various operations (e.g., receive, monitor, transmit) using the receiver 710, the transmitter 715, or both, or otherwise cooperate with the receiver 710, the transmitter 715, or both. For example, the communication manager 720 can receive information from the receiver 710, send information to the transmitter 715, or integrate with the receiver 710, the transmitter 715, or both to receive information, send information, or perform various other operations as described herein.

[0167] According to examples disclosed herein, the communication manager 720 can support wireless communication at the UE. The sidelink control information transmitter 725 can be configured to or otherwise support a unit for transmitting sidelink control information, where the sidelink control information signals a set of resources and the number of spatial layers for sidelink transmission by the UE, and where the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer and a second spatial layer of the sidelink transmission. The data transmitter 730 can be configured to or otherwise support a unit for transmitting a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing. The data transmitter 730 can be configured to or otherwise support a unit for transmitting a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0168] Additionally or alternatively, according to an example as disclosed herein, a communication manager 720 may support wireless communication at a UE. A sidelink control information receiver 735 may be configured to or otherwise support a unit for receiving sidelink control information, which signals a set of resources and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. A data receiver 740 may be configured to or otherwise support a unit for receiving a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing. The data receiver 740 may be configured to or otherwise support a unit for receiving a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0169] Figure 8 FIG. 800 is a block diagram illustrating a communication manager 820 that supports control information for sidelink spatial domain multiplexing from multiple TRPs, in accordance with aspects of the present disclosure. The communication manager 820 may be an example of aspects of the communication manager 620, the communication manager 720, or both as described herein. The communication manager 820 or its various components may be examples of units for performing various aspects of the control information for sidelink spatial domain multiplexing from multiple TRPs as described herein. For example, the communication manager 820 may include a sidelink control information transmitter 825, a data transmitter 830, a sidelink control information receiver 835, a data receiver 840, a HARQ process identifier component 845, an MCS component 850, a DMRS component 855, a destination identifier component 860, a broadcast type component 865, a new data indicator component 870, a communication range indicator component 875, a resource determination component 880, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0170] According to an example as disclosed herein, a communication manager 820 may support wireless communication at a UE. A sidelink control information transmitter 825 may be configured to or otherwise support a unit for transmitting sidelink control information, which signals a set of resources and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission.

[0171] The data transmitter 830 may be configured to or otherwise support a unit for transmitting a first data packet from a first TRP on a first spatial layer for sidelink transmission using a resource set and based on an indication of spatial domain multiplexing. In some examples, the data transmitter 830 may be configured to or otherwise support a unit for transmitting a second data packet from a second TRP on a second spatial layer for sidelink transmission using a resource set and based on an indication of spatial domain multiplexing.

[0172] In some examples, the HARQ process identifier component 845 may be configured to or otherwise support a unit for assigning a first HARQ process identifier to the first spatial layer and a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0173] In some examples, the indication of spatial domain multiplexing includes using a shared first phase of sidelink control information and a separate second phase of sidelink control information for the first spatial layer and the second spatial layer.

[0174] In some examples, the MCS component 850 may be configured to or otherwise support a unit for assigning a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein the shared first phase of sidelink control information signals the common modulation and coding scheme. In some examples, the assignment of the common modulation and coding scheme is based on the size of the first data packet and the size of the second data packet with respect to the resource set. In some examples, the common modulation and coding scheme corresponds to the subchannel size available for sidelink transmission.

[0175] In some examples, the MCS component 850 may be configured to or otherwise support a unit for assigning separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode the first data packet and the second data packet respectively, wherein the sidelink control information signals the separate modulation and coding schemes.

[0176] In some examples, to support the transmission of sidelink control information, the sidelink control information transmitter 825 may be configured to or otherwise support a unit for transmitting the shared first phase of sidelink control information, the shared first phase indicating separate modulation and coding schemes for the first spatial layer and the second spatial layer.

[0177] In some examples, to support the transmission of sidelink control information, the sidelink control information transmitter 825 may be configured to or otherwise support units for a separate second phase for transmitting sidelink control information for a first spatial layer and a second spatial layer using respective separate modulation and coding schemes.

[0178] In some examples, to support the transmission of sidelink control information, the sidelink control information transmitter 825 may be configured to or otherwise support units for a shared first phase for transmitting sidelink control information, where the shared first phase indicates a common modulation and coding scheme for decoding respective separate second phases for a first spatial layer and a second spatial layer. In some examples, to support the transmission of sidelink control information, the sidelink control information transmitter 825 may be configured to or otherwise support units for respective separate second phases for transmitting sidelink control information using a common modulation and coding scheme, where the second phase of the sidelink control information for the first spatial layer indicates one of the separate modulation and coding schemes for decoding a first data packet, and where the second phase of the sidelink control message for the second spatial layer indicates one of the separate modulation and coding schemes for decoding a second data packet.

[0179] In some examples, the assignment of the separate modulation and coding schemes is based on the size of the first data packet and the size of the second data packet relative to a resource set.

[0180] In some examples, the DMRS component 855 may be configured to or otherwise support units for assigning different demodulation reference signal ports to a first spatial layer and a second spatial layer, where the sidelink control information signals the different demodulation reference signal ports.

[0181] In some examples, the sidelink control information signals a shared reservation priority for a first spatial layer and a second spatial layer. In some examples, the sidelink control information signals respective reservation priorities for each of a first spatial layer and a second spatial layer.

[0182] In some examples, the destination identifier component 860 may be configured to or otherwise support units for assigning separate destination identifiers to a first spatial layer and a second spatial layer, where the sidelink control information signals the separate destination identifiers.

[0183] In some examples, the broadcast type component 865 may be configured to or otherwise support units for assigning separate broadcast types to a first spatial layer and a second spatial layer, where the sidelink control information signals the separate broadcast types.

[0184] In some examples, the new data indicator component 870 may be configured to or otherwise support a unit for assigning separate new data indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate new data indicators.

[0185] In some examples, the communication range indicator component 875 may be configured to or otherwise support a unit for assigning separate communication range indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information includes the separate communication range indicators.

[0186] In some examples, the resource determination component 880 may be configured to or otherwise support a unit for determining a set of resources for sidelink transmission based on the measured signal strength associated with each of the first TRP and the second TRP. In some examples, the set of resources includes the same transmission time interval for the first TRP and the second TRP.

[0187] In some examples, to support determining the set of resources, the resource determination component 880 may be configured to or otherwise support a unit for selecting the reservation size of the set of resources based on the larger of the first data packet or the second data packet. In some examples, to support determining the set of resources, the resource determination component 880 may be configured to or otherwise support a unit for adjusting the resource exclusion signal strength threshold to enable transmission of the first spatial stream at the first TRP and transmission of the second spatial stream at the second TRP.

[0188] Additionally or alternatively, according to examples disclosed herein, the communication manager 820 may support wireless communication at the UE. The sidelink control information receiver 835 may be configured to or otherwise support a unit for receiving sidelink control information, the sidelink control information signaling a set of resources for sidelink transmission and the number of spatial layers, wherein the sidelink control information includes an indication of spatial domain multiplexing between the first spatial layer of the sidelink transmission and the second spatial layer of the sidelink transmission. The data receiver 840 may be configured to or otherwise support a unit for receiving the first data packet from the first TRP on the first spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing. The data receiver 840 may be configured to or otherwise support a unit for receiving the second data packet from the second TRP on the second spatial layer of the sidelink transmission using the set of resources and based on the indication of spatial domain multiplexing.

[0189] In some examples, the HARQ process identifier component 845 may be configured to or otherwise support a unit for assigning a first HARQ process identifier to a first spatial layer and a second HARQ process identifier to a second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0190] In some examples, the indication of spatial domain multiplexing includes using a shared first phase of the sidelink control information and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

[0191] In some examples, to support receiving sidelink control information, the MCS component 850 may be configured to or otherwise support a unit for determining a common modulation and coding scheme for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the common modulation and coding scheme.

[0192] In some examples, to support receiving sidelink control information, the MCS component 850 may be configured to or otherwise support a unit for determining separate modulation and coding schemes for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate modulation and coding schemes.

[0193] In some examples, to support receiving sidelink control information, the DMRS component 855 may be configured to or otherwise support a unit for determining different demodulation reference signal ports for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

[0194] In some examples, the sidelink control information signals a shared reservation priority for the first spatial layer and the second spatial layer. In some examples, the sidelink control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

[0195] In some examples, to support receiving sidelink control information, the destination identifier component 860 may be configured to or otherwise support a unit for determining respective destination identifiers for the first spatial layer and the second spatial layer, wherein the sidelink control information signals separate destination identifiers.

[0196] In some examples, to support receiving sidelink control information, the broadcast type component 865 may be configured to or otherwise support a unit for determining respective broadcast types for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the respective broadcast types.

[0197] In some examples, to support receiving sidelink control information, the new data indicator component 870 may be configured to or otherwise support units for receiving new data indicators for a first spatial layer and a second spatial layer, where the sidelink control information signals separate new data indicators.

[0198] In some examples, the communication range indicator component 875 may be configured to or otherwise support units for assigning separate communication range indicators to a first spatial layer and a second spatial layer, where the sidelink control information includes separate communication range indicators.

[0199] Figure 9 FIG. showing a system 900 including a device 905 supporting control information for sidelink spatial domain multiplexing from multiple TRPs, according to aspects of the present disclosure. The device 905 may be an example of or include components of the device 605, the device 705, or the UE 115 as described herein. The device 905 may wirelessly communicate with one or more base stations 105, UEs 95, or any combination thereof. The device 905 may include components for two-way voice and data communication, including components for sending and receiving communications, such as a communication manager 920, an input / output (I / O) controller 910, a transceiver 915, an antenna 925, a memory 930, code 935, and a processor 940. These components may be electronically communicatively or otherwise (e.g., operably, communicatively, functionally, electronically, electrically) coupled via one or more buses (e.g., bus 945).

[0200] The I / O controller 910 may manage input and output signals for the device 905. The I / O controller 910 may also manage peripheral devices not integrated into the device 905. In some cases, the I / O controller 910 may represent a physical connection or port to an external peripheral device. In some cases, the I / O controller 910 may utilize an operating system, such as or another known operating system. Additionally or alternatively, the I / O controller 910 may represent or interact with a modem, a keyboard, a mouse, a touch screen, or similar devices. In some cases, the I / O controller 910 may be implemented as part of a processor (such as the processor 940). In some cases, a user may interact with the device 905 via the I / O controller 910 or via hardware components controlled by the I / O controller 910.

[0201] In some cases, device 905 may include a single antenna 925. However, in some other cases, device 905 may have more than one antenna 925 that can simultaneously transmit or receive multiple wireless transmissions. Transceiver 915 can communicate bidirectionally via one or more antennas 925, wired or wireless links as described herein. For example, transceiver 915 can represent a wireless transceiver and can communicate bidirectionally with another wireless transceiver. Transceiver 915 can also include a modem for modulating packets to provide the modulated packets to one or more antennas 925 for transmission and demodulating packets received from one or more antennas 925. Transceiver 915 or transceiver 915 and one or more antennas 925 can be examples of transmitter 615, transmitter 715, receiver 610, receiver 710, or any combination thereof or components thereof as described herein.

[0202] Memory 930 can include random access memory (RAM) and read-only memory (ROM). Memory 930 can store computer-readable, computer-executable code 935 that includes instructions that, when executed by processor 940, cause device 905 to perform the various functions described herein. Code 935 can be stored in a non-transitory computer-readable medium (such as system memory or another type of memory). In some cases, code 935 may not be directly executable by processor 940 but can cause a computer (e.g., when compiled and executed) to perform the functions described herein. In some cases, in addition, memory 930 may also contain a basic input / output system (BIOS) that can control basic hardware or software operations, such as interactions with peripheral components or devices.

[0203] Processor 940 can include intelligent hardware devices (e.g., a general-purpose processor, DSP, CPU, microcontroller, ASIC, FPGA, programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 940 can be configured to operate a memory array using a memory controller. In some other cases, the memory controller can be integrated into processor 940. Processor 940 can be configured to execute computer-readable instructions stored in a memory (e.g., memory 930) to cause device 905 to perform various functions (e.g., functions or tasks supporting control information for sidelink spatial domain multiplexing from multiple TRPs). For example, device 905 or components of device 905 can include processor 940 and memory 930 coupled to processor 940, and processor 940 and memory 930 are configured to perform the various functions described herein.

[0204] According to examples disclosed herein, communication manager 920 may support wireless communication at a UE. For example, communication manager 920 may be configured to or otherwise support a unit for transmitting sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, where the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. Communication manager 920 may be configured to or otherwise support a unit for transmitting a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing. Communication manager 920 may be configured to or otherwise support a unit for transmitting a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0205] Additionally or alternatively, according to examples disclosed herein, communication manager 920 may support wireless communication at a UE. For example, communication manager 920 may be configured to or otherwise support a unit for receiving sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, where the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. Communication manager 920 may be configured to or otherwise support a unit for receiving a first data packet from a first TRP on a first spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing. Communication manager 920 may be configured to or otherwise support a unit for receiving a second data packet from a second TRP on a second spatial layer of the sidelink transmission using the resource set and based on the indication of spatial domain multiplexing.

[0206] By including or configuring communication manager 920 according to examples described herein, device 905 may support improved techniques for directed sidelink transmission in the context of a multi-TRP UE 115. For example, by implementing sidelink control information that supports simultaneous SDM sidelink transmission, the number of sidelink transmissions and retransmissions may be reduced, thereby reducing network overhead, increasing the coverage area, and improving efficiency. Additionally, by implementing simultaneous SDM sidelink transmission, aspects of the present disclosure provide a reduced number of sidelink transmissions and retransmissions, thereby reducing processing resources at the multi-TRP UE 115 and the receiver UE 115, reducing power consumption, and improving battery performance.

[0207] In some examples, the communication manager 920 may be configured to perform various operations (e.g., receive, monitor, transmit) using the transceiver 915, one or more antennas 925, or any combination thereof, or in cooperation with the transceiver 915, one or more antennas 925, or any combination thereof. Although the communication manager 920 is shown as a separate component, in some examples, one or more of the functions described with reference to the communication manager 920 may be supported or performed by the processor 940, the memory 930, the code 935, or any combination thereof. For example, the code 935 may include instructions executable by the processor 940 to cause the device 905 to perform various aspects of the control information for sidelink spatial domain multiplexing from multiple TRPs as described herein, or the processor 940 and the memory 930 may otherwise be configured to perform or support such operations.

[0208] Figure 10 FIG. 1000 is a flow diagram illustrating a method 1000 for supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure. The operations of method 1000 may be implemented by a UE or its components as described herein. For example, the operations of method 1000 may be performed by the UE 115 as described with reference to Figures 1 to 9 In some examples, the UE may execute an instruction set to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functions.

[0209] At 1005, the method may include: transmitting sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. The operation of 1005 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1005 may be performed by the sidelink control information transmitter 825 as described with reference to Figure 8 At 1010, the method may include: transmitting a first data packet on a first spatial layer of the sidelink transmission from a first TRP using the resource set and based on the indication of spatial domain multiplexing. The operation of 1010 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1010 may be performed by the data transmitter 830 as described with reference to

[0210] At 1010, the method may include: transmitting a first data packet on a first spatial layer of the sidelink transmission from a first TRP using the resource set and based on the indication of spatial domain multiplexing. The operation of 1010 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1010 may be performed by the data transmitter 830 as described with reference to Figure 8 At 1010, the method may include: transmitting a first data packet on a first spatial layer of the sidelink transmission from a first TRP using the resource set and based on the indication of spatial domain multiplexing. The operation of 1010 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operation of 1010 may be performed by the data transmitter 830 as described with reference to

[0211] At 1015, the method may include: using a resource set and transmitting a second data packet from a second TRP on a second spatial layer of a sidelink transmission based on an indication of spatial domain reuse. The operations of 1015 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1015 may be performed by a data transmitter 830 as described with reference to Figure 8 described.

[0212] Figure 11 FIG. 1100 is a flow diagram illustrating a method for supporting control information for sidelink spatial domain reuse from multiple TRPs in accordance with aspects of the present disclosure. The operations of method 1100 may be implemented by a UE or components thereof as described herein. For example, the operations of method 1100 may be performed by a UE 115 as described with reference to Figures 1 to 9 described. In some examples, the UE may execute an instruction set to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functions.

[0213] At 1105, the method may include: transmitting sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain reuse between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. The operations of 1105 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1105 may be performed by a sidelink control information transmitter 825 as described with reference to Figure 8 described.

[0214] At 1110, the method may include: assigning a first HARQ process identifier to the first spatial layer and assigning a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain reuse includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer. The operations of 1110 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1110 may be performed by a HARQ process identifier component 845 as described with reference to Figure 8 described.

[0215] At 1115, the method may include: assigning a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein a first shared phase of the sidelink control information signals the common modulation and coding scheme. The operations of 1115 may be performed according to the examples disclosed herein. In some examples, aspects of the operations of 1115 may be performed by a Figure 8be performed by the described MCS component 850.

[0216] At 1120, the method may include: using a resource set and transmitting a first data packet from a first TRP on a first spatial layer of a sidelink transmission based on an indication of spatial domain multiplexing. The operations of 1120 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1120 may be performed by the data transmitter 830 as described with reference to Figure 8 the described data transmitter 830.

[0217] At 1125, the method may include: using a resource set and transmitting a second data packet from a second TRP on a second spatial layer of a sidelink transmission based on an indication of spatial domain multiplexing. The operations of 1125 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1125 may be performed by the data transmitter 830 as described with reference to Figure 8 the described data transmitter 830.

[0218] Figure 12 FIG. 1200 is a flow chart illustrating a method for supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure. The operations of method 1200 may be implemented by a UE or its components as described herein. For example, the operations of method 1200 may be performed by the UE 115 as described with reference to Figures 1 to 9 the described UE 115. In some examples, the UE may execute an instruction set to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functions.

[0219] At 1205, the method may include: receiving sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission. The operations of 1205 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1205 may be performed by the sidelink control information receiver 835 as described with reference to Figure 8 the described sidelink control information receiver 835.

[0220] At 1210, the method may include: using a resource set and receiving a first data packet from a first TRP on a first spatial layer of a sidelink transmission based on an indication of spatial domain multiplexing. The operations of 1210 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1210 may be performed by the data receiver 840 as described with reference to Figure 8 the described data receiver 840.

[0221] At 1215, the method may include: using a resource set and receiving, on a second spatial layer of a sidelink transmission and based on an indication of spatial domain multiplexing, a second data packet from a second TRP. The operations of 1215 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operations of 1215 may be performed by a data receiver 840 as described with reference to Figure 8 .

[0222] Figure 13 FIG. 1300 is a flow diagram illustrating a method for supporting control information for sidelink spatial domain multiplexing from multiple TRPs in accordance with aspects of the present disclosure. The operations of method 1300 may be implemented by a UE or components thereof as described herein. For example, the operations of method 1300 may be performed by a UE 115 as described with reference to Figures 1 to 9 . In some examples, the UE may execute an instruction set to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functions.

[0223] At 1305, the method may include: receiving sidelink control information that signals a resource set and a number of spatial layers for a sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer and a second spatial layer of the sidelink transmission. The operations of 1305 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operations of 1305 may be performed by a sidelink control information receiver 835 as described with reference to Figure 8 .

[0224] At 1310, the method may include: assigning a first HARQ process identifier to the first spatial layer and assigning a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer. The operations of 1310 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operations of 1310 may be performed by a HARQ process identifier component 845 as described with reference to Figure 8 .

[0225] At 1315, the method may include: determining a common modulation and coding scheme for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the common modulation and coding scheme. The operations of 1315 may be performed in accordance with the examples disclosed herein. In some examples, aspects of the operations of 1315 may be performed by an MCS component 850 as described with reference to Figure 8 .

[0226] At 1320, the method may include: using a resource set and receiving a first data packet from a first TRP on a first spatial layer of a sidelink transmission based on an indication of spatial domain multiplexing. The operations of 1320 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1320 may be performed by a data receiver 840 as described with reference to Figure 8 the data receiver 840 described.

[0227] At 1325, the method may include: using a resource set and receiving a second data packet from a second TRP on a second spatial layer of a sidelink transmission based on an indication of spatial domain multiplexing. The operations of 1325 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1325 may be performed by a data receiver 840 as described with reference to Figure 8 the data receiver 840 described.

[0228] Aspects of the present disclosure are summarized below:

[0229] Aspect 1: A method for wireless communication at a UE, including: transmitting sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; using the resource set and transmitting a first data packet from a first transmit / receive point (TRP) on the first spatial layer of the sidelink transmission at least in part based on the indication of spatial domain multiplexing; and using the resource set and transmitting a second data packet from a second TRP on the second spatial layer of the sidelink transmission at least in part based on the indication of spatial domain multiplexing.

[0230] Aspect 2: The method according to aspect 1, further including: assigning a first HARQ process identifier to the first spatial layer and assigning a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0231] Aspect 3: The method according to any one of aspects 1 to 2, wherein the indication of spatial domain multiplexing includes using a shared first phase of the sidelink control information and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

[0232] Aspect 4: The method according to any one of aspects 1 to 3, further including: assigning a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein the shared first phase of the sidelink control information signals the common modulation and coding scheme.

[0233] Aspect 5: The method according to aspect 4, wherein assigning a common modulation and coding scheme is at least partially based on the size of the first data packet and the size of the second data packet with respect to the resource set.

[0234] Aspect 6: The method according to any one of aspects 4 to 5, wherein the common modulation and coding scheme corresponds to the sub-channel size available for sidelink transmission.

[0235] Aspect 7: The method according to any one of aspects 1 to 3, further comprising: assigning separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode the first data packet and the second data packet respectively, wherein the sidelink control information signals the separate modulation and coding schemes.

[0236] Aspect 8: The method according to aspect 7, wherein transmitting the sidelink control information includes: transmitting a shared first phase of the sidelink control information, the shared first phase indicating the separate modulation and coding schemes for the first spatial layer and the second spatial layer.

[0237] Aspect 9: The method according to aspect 8, wherein transmitting the sidelink control information includes: transmitting a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer using the respective separate modulation and coding schemes.

[0238] Aspect 10: The method according to any one of aspects 7 to 9, wherein transmitting the sidelink control information includes: transmitting a shared first phase of the sidelink control information, the shared first phase indicating a common modulation and coding scheme for the respective separate second phases of decoding the first spatial layer and the second spatial layer; and transmitting the respective separate second phases of the sidelink control information using the common modulation and coding scheme, wherein the second phase of the sidelink control information for the first spatial layer indicates one of the separate modulation and coding schemes for decoding the first data packet, and wherein the second phase of the sidelink control message for the second spatial layer indicates one of the separate modulation and coding schemes for decoding the second data packet.

[0239] Aspect 11: The method according to any one of aspects 7 to 10, wherein assigning the separate modulation and coding schemes is at least partially based on the size of the first data packet and the size of the second data packet with respect to the resource set.

[0240] Aspect 12: The method according to any one of Aspects 1 to 11 further includes: assigning different demodulation reference signal ports to a first spatial layer and a second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

[0241] Aspect 13: The method according to any one of Aspects 1 to 12, wherein the sidelink control information signals a shared reservation priority for the first spatial layer and the second spatial layer.

[0242] Aspect 14: The method according to any one of Aspects 1 to 13, wherein the sidelink control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

[0243] Aspect 15: The method according to any one of Aspects 1 to 14 further includes: assigning separate destination identifiers to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate destination identifiers.

[0244] Aspect 16: The method according to any one of Aspects 1 to 15 further includes: assigning separate broadcast types to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate broadcast types.

[0245] Aspect 17: The method according to any one of Aspects 1 to 16 further includes: assigning separate new data indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate new data indicators.

[0246] Aspect 18: The method according to any one of Aspects 1 to 17 further includes: assigning separate communication range indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information includes the separate communication range indicators.

[0247] Aspect 19: The method according to any one of Aspects 1 to 18 further includes: determining a resource set for sidelink transmission at least in part based on the measured signal strength associated with each of a first TRP and a second TRP.

[0248] Aspect 20: The method according to Aspect 19, wherein the resource set includes the same transmission time interval for the first TRP and the second TRP.

[0249] Aspect 21: The method according to any one of Aspects 19 to 20, wherein determining the resource set includes: selecting a reservation size of the resource set at least in part based on the larger of a first data packet or a second data packet.

[0250] Aspect 22: The method according to any one of aspects 19 to 21, wherein determining the resource set includes: adjusting a resource exclusion signal strength threshold to enable transmission of a first spatial stream at a first TRP and transmission of a second spatial stream at a second TRP.

[0251] Aspect 23: A method for wireless communication at a UE, comprising: receiving sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; using the resource set and receiving a first data packet from a first transmit / receive point (TRP) on the first spatial layer of the sidelink transmission at least partially based on the indication of spatial domain multiplexing; and using the resource set and receiving a second data packet from a second TRP on the second spatial layer of the sidelink transmission at least partially based on the indication of spatial domain multiplexing.

[0252] Aspect 24: The method according to aspect 23, further comprising: assigning a first HARQ process identifier to the first spatial layer and assigning a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer.

[0253] Aspect 25: The method according to any one of aspects 23 to 24, wherein the indication of spatial domain multiplexing includes using a shared first phase of the sidelink control information and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

[0254] Aspect 26: The method according to any one of aspects 23 to 25, wherein receiving the sidelink control information includes: determining a common modulation and coding scheme for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the common modulation and coding scheme.

[0255] Aspect 27: The method according to any one of aspects 23 to 25, wherein receiving the sidelink control information includes: determining separate modulation and coding schemes for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate modulation and coding schemes.

[0256] Aspect 28: The method according to any one of aspects 23 to 27, wherein receiving the sidelink control information includes: determining different demodulation reference signal ports for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

[0257] Aspect 29: The method according to any one of aspects 23 to 28, wherein the sidelink control information signals the shared reservation priorities for the first spatial layer and the second spatial layer.

[0258] Aspect 30: The method according to any one of aspects 23 to 29, wherein the sidelink control information signals the respective reservation priorities for each of the first spatial layer and the second spatial layer.

[0259] Aspect 31: The method according to any one of aspects 23 to 30, wherein receiving the sidelink control information includes: determining respective destination identifiers for the first spatial layer and the second spatial layer, wherein the sidelink control information signals separate destination identifiers.

[0260] Aspect 32: The method according to any one of aspects 23 to 31, wherein receiving the sidelink control information includes: determining the respective broadcast types for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the respective broadcast types.

[0261] Aspect 33: The method according to any one of aspects 23 to 32, wherein receiving the sidelink control information includes: receiving a new data indicator for the first spatial layer and the second spatial layer, wherein the sidelink control information signals a separate new data indicator.

[0262] Aspect 34: The method according to any one of aspects 23 to 33, further comprising: assigning separate communication range indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information includes the separate communication range indicators.

[0263] Aspect 35: An apparatus for wireless communication at a UE, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to any one of aspects 1 to 22.

[0264] Aspect 36: An apparatus for wireless communication at a UE, comprising at least one unit for performing the method according to any one of aspects 1 to 22.

[0265] Aspect 37: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code including instructions executable by a processor to perform the method according to any one of aspects 1 to 22.

[0266] Aspect 38: An apparatus for wireless communication at a UE, comprising: a processor; a memory coupled to the processor; and instructions that are stored in the memory and executable by the processor to cause the apparatus to perform the method according to any of Aspects 23 to 34.

[0267] Aspect 39: An apparatus for wireless communication at a UE, comprising at least one unit for performing the method according to any of Aspects 23 to 34.

[0268] Aspect 40: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method according to any of Aspects 23 to 34.

[0269] It should be noted that the method descriptions herein describe possible implementations, and the operations and steps may be rearranged or otherwise modified, and other implementations are possible. Additionally, aspects from two or more methods may be combined.

[0270] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described by way of example and the LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond the scope of LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to a variety of other wireless communication systems such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0271] The information and signals described herein may be represented using any of a variety of different technologies and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout the specification may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0272] Various illustrative blocks and components described in connection with the present disclosure can be implemented or performed using a general purpose processor, a DSP, an ASIC, a CPU, an FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0273] The functions described herein can be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions can be stored on or transmitted via a computer-readable medium as one or more instructions or code. Other examples and implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein can be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination of these items. Features implementing the functions can also be physically located at various positions, including being distributed such that portions of the functions are implemented at different physical locations.

[0274] A computer-readable medium includes both a non-transitory computer storage medium and a communication medium, where the communication medium includes any medium that facilitates transfer of a computer program from one place to another. The non-transitory storage medium can be any available medium that can be accessed by a general purpose or special purpose computer. By way of example and not limitation, the non-transitory computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc read-only memory (CD-ROM) or other optical disc storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code units in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer, or a general purpose or special purpose processor. Additionally, any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. As used herein, disk and disc include CD, laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray disc, where disks typically reproduce data magnetically, while discs reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable medium.

[0275] As used herein (including in the claims), the "or" as used in a list of items (e.g., a list of items that ends with a phrase such as "at least one of" or "one or more of") indicates an inclusive list, such that a list of at least one of A, B, or C, for example, means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

[0276] Furthermore, as used herein, the phrase "

[0277] based on" should not be construed as a reference to a closed set of conditions. For example, an example step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "at least partially based on".

[0278] In the drawings, similar components or features may have the same reference numeral. Additionally, various components of the same type may be distinguished by following the reference numeral with a dash and a second label used to differentiate among similar components. If only the first reference numeral is used in the specification, the description applies to any one of the similar components having the same first reference numeral, regardless of the second reference numeral or any other subsequent reference numerals.

[0279] The description set forth herein with reference to the drawings describes example configurations and does not represent all examples that may be implemented or are within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration" and not "preferred" or "advantageous over other examples." For the purpose of providing an understanding of the described technology, the detailed description includes specific details. However, the technology may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0280] The present description is provided to enable a person skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for wireless communication at a user equipment (UE), comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: transmit sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer and a second spatial layer of the sidelink transmission; assign a first hybrid automatic repeat request (HARQ) process identifier to the first spatial layer and a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer; use the resource set and at least partially based on the indication of spatial domain multiplexing to transmit a first data packet from a first TRP on the first spatial layer of the sidelink transmission; and use the resource set and at least partially based on the indication of spatial domain multiplexing to transmit a second data packet from a second TRP on the second spatial layer of the sidelink transmission.

2. The device according to claim 1, wherein The indication of spatial domain multiplexing includes using a shared first phase and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

3. The device according to claim 1, wherein, The instructions are further executable by the processor to cause the apparatus to: assign a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein the shared first phase of the sidelink control information signals the common modulation and coding scheme.

4. The apparatus according to claim 3, wherein, Assigning the common modulation and coding scheme is at least partially based on the size of the first data packet and the size of the second data packet relative to the resource set.

5. The apparatus according to claim 3, wherein, The common modulation and coding scheme corresponds to a subchannel size available for the sidelink transmission.

6. The device according to claim 1, wherein The instructions are further executable by the processor to cause the apparatus to: assign separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode the first data packet and the second data packet respectively, wherein the sidelink control information signals the separate modulation and coding schemes.

7. The apparatus according to claim 6, wherein, Instructions for transmitting the sidelink control information are executable by the processor to cause the apparatus to: transmit the shared first phase of the sidelink control information, which indicates the separate modulation and coding schemes for the first spatial layer and the second spatial layer.

8. The apparatus according to claim 7, wherein Instructions for transmitting the sidelink control information are further executable by the processor to cause the apparatus to: A separate second phase of transmitting the sidelink control information for the first spatial layer and the second spatial layer using respective separate modulation and coding schemes.

9. The device according to claim 6, wherein, Instructions for transmitting the sidelink control information may be executed by the processor to cause the device to perform the following operations: Transmit a shared first phase of the sidelink control information, the shared first phase indicating a common modulation and coding scheme for decoding respective separate second phases of the first spatial layer and the second spatial layer; And Transmit the respective separate second phases of the sidelink control information using the common modulation and coding scheme, wherein the second phase of the sidelink control information for the first spatial layer indicates one modulation and coding scheme of the separate modulation and coding schemes for decoding the first data packet, and wherein the second phase of the sidelink control message for the second spatial layer indicates one modulation and coding scheme of the separate modulation and coding schemes for decoding the second data packet.

10. The apparatus according to claim 6, wherein, Assigning the separate modulation and coding schemes is at least partially based on the size of the first data packet and the size of the second data packet relative to the resource set.

11. The device according to claim 1, wherein, The instructions may also be executed by the processor to cause the device to perform the following operations: Assign different demodulation reference signal ports to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

12. The apparatus according to claim 1, wherein The sidelink control information signals a shared reservation priority for the first spatial layer and the second spatial layer.

13. The device according to claim 1, wherein The sidelink control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

14. The device according to claim 1, wherein, The instructions may also be executed by the processor to cause the device to perform the following operations: Assign separate destination identifiers to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate destination identifiers.

15. The device according to claim 1, wherein The instructions may also be executed by the processor to cause the device to perform the following operations: Assign separate broadcast types to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate broadcast types.

16. The device according to claim 1, wherein, The instructions may also be executed by the processor to cause the device to perform the following operations: Assign separate new data indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate new data indicators.

17. The apparatus according to claim 1, wherein The instructions may also be executed by the processor to cause the device to perform the following operations: Assign separate communication range indicators to the first spatial layer and the second spatial layer, wherein the sidelink control information includes the separate communication range indicators.

18. The device according to claim 1, wherein The instructions may also be executed by the processor to cause the device to perform the following operations: Determine the resource set for the sidelink transmission based at least in part on the measurement signal strengths associated with each of the first TRP and the second TRP.

19. The apparatus according to claim 18, wherein, The resource set includes the same transmission time interval for the first TRP and the second TRP.

20. The apparatus according to claim 18, wherein, Instructions for determining the resource set are executable by the processor to cause the device to: Select a reservation size of the resource set based at least in part on the larger of the first data packet or the second data packet.

21. The device according to claim 18, wherein, Instructions for determining the resource set are executable by the processor to cause the device to: Adjust a resource exclusion signal strength threshold to enable transmission on the first spatial layer at the first TRP and transmission on the second spatial layer at the second TRP.

22. A device for wireless communication at a user equipment (UE), comprising: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the device to: Receive sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; Assign a first hybrid automatic repeat request (HARQ) process identifier to the first spatial layer and assign a second HARQ process identifier to the second spatial layer, wherein the indication of spatial domain multiplexing includes an indication of the first HARQ process identifier for the first spatial layer and an indication of the second HARQ process identifier for the second spatial layer; Use the resource set and receive a first data packet from a first TRP on the first spatial layer of the sidelink transmission based at least in part on the indication of spatial domain multiplexing; and Use the resource set and receive a second data packet from a second TRP on the second spatial layer of the sidelink transmission based at least in part on the indication of spatial domain multiplexing.

23. The device according to claim 22, wherein, The indication of spatial domain multiplexing includes using a shared first phase of the sidelink control information and a separate second phase of the sidelink control information for the first spatial layer and the second spatial layer.

24. The device according to claim 22, wherein, Instructions for receiving the sidelink control information are executable by the processor to cause the device to: Determine a common modulation and coding scheme for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the common modulation and coding scheme.

25. The apparatus according to claim 22, wherein, Instructions for receiving the sidelink control information are executable by the processor to cause the device to: Determine separate modulation and coding schemes for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the separate modulation and coding schemes.

26. The device according to claim 22, wherein Instructions for receiving the sidelink control information may be executed by the processor to cause the device to perform the following operations: Determine different demodulation reference signal ports for the first spatial layer and the second spatial layer, wherein the sidelink control information signals the different demodulation reference signal ports.

27. The apparatus according to claim 22, wherein, The sidelink control information signals a shared reservation priority for the first spatial layer and the second spatial layer.

28. The apparatus according to claim 22, wherein, The sidelink control information signals a respective reservation priority for each of the first spatial layer and the second spatial layer.

29. A device for wireless communication at a user equipment (UE), comprising: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the device to perform the following operations: Transmit sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; Assign a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein a shared first phase of the sidelink control information signals the common modulation and coding scheme, wherein assigning the common modulation and coding scheme is at least partially based on a size of a first data packet and a size of a second data packet relative to the resource set; Use the resource set and at least partially based on the indication of spatial domain multiplexing to transmit the first data packet from a first TRP on the first spatial layer of the sidelink transmission; and Use the resource set and at least partially based on the indication of spatial domain multiplexing to transmit the second data packet from a second TRP on the second spatial layer of the sidelink transmission.

30. A device for wireless communication at a user equipment (UE), comprising: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the device to perform the following operations: Transmit sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; Assign a common modulation and coding scheme to the first spatial layer and the second spatial layer, wherein a shared first phase of the sidelink control information signals the common modulation and coding scheme, wherein the common modulation and coding scheme corresponds to a subchannel size available for the sidelink transmission; Transmit a first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and at least partially based on the indication of spatial domain multiplexing; and Transmit a second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and at least partially based on the indication of spatial domain multiplexing.

31. An apparatus for wireless communication at a user equipment (UE), comprising: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the apparatus to perform the following operations: Transmit sidelink control information that signals a resource set and a number of spatial layers for sidelink transmission by the UE, wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer and a second spatial layer of the sidelink transmission; Assign separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode a first data packet and a second data packet respectively, wherein the sidelink control information signals the separate modulation and coding schemes; Transmit the first data packet from a first TRP on the first spatial layer of the sidelink transmission using the resource set and at least partially based on the indication of spatial domain multiplexing; and Transmit the second data packet from a second TRP on the second spatial layer of the sidelink transmission using the resource set and at least partially based on the indication of spatial domain multiplexing; Wherein the instructions for transmitting the sidelink control information are executable by the processor to cause the apparatus to perform the following operations: Transmit a shared first stage of the sidelink control information that indicates a common modulation and coding scheme for respective separate second stages of decoding the first spatial layer and the second spatial layer; and Transmit the respective separate second stages of the sidelink control information using the common modulation and coding scheme, wherein the second stage of the sidelink control information for the first spatial layer indicates one of the separate modulation and coding schemes for decoding the first data packet, and wherein the second stage of the sidelink control message for the second spatial layer indicates one of the separate modulation and coding schemes for decoding the second data packet.

32. An apparatus for wireless communication at a user equipment (UE), comprising: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the apparatus to perform the following operations: Transmit sidelink control information, where the sidelink control information signals a resource set and a number of spatial layers for sidelink transmission by the UE, and wherein the sidelink control information includes an indication of spatial domain multiplexing between a first spatial layer of the sidelink transmission and a second spatial layer of the sidelink transmission; Assign separate modulation and coding schemes to the first spatial layer and the second spatial layer to decode a first data packet and a second data packet respectively, where the sidelink control information signals the separate modulation and coding schemes, and wherein the assignment of the separate modulation and coding schemes is at least partially based on the size of the first data packet and the size of the second data packet relative to the resource set; Use the resource set and transmit the first data packet from a first TRP on the first spatial layer of the sidelink transmission at least partially based on the indication of spatial domain multiplexing; and Use the resource set and transmit the second data packet from a second TRP on the second spatial layer of the sidelink transmission at least partially based on the indication of spatial domain multiplexing.

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