Reporting number of transmit antennas for wireless communication

Abstract

Methods, systems, and devices for wireless communication are described. In some systems, a user equipment (UE) may receive control signaling indicating a number of transmit antennas at a network entity. The number of transmit antennas may include antennas that are activated for downlink transmissions to the UE. The UE may transmit a channel state information (CSI) report indicating a set of one or more CSI parameters. The set of one or more CSI parameters may be based on the number of transmit antennas at the network entity indicated via the control signaling. After sending the CSI report, the UE may communicate with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

Description

Cross - Reference to Related Applications

[0001] This patent application claims priority to U.S. Patent Application No. 18 / 052,873, titled "REPORTING QUANTITY OF TRANSMIT ANTENNAS FOR WIRELESS COMMUNICATIONS", filed on November 4, 2022, by Pick et al., which is assigned to the assignee of the present application and is hereby incorporated by reference in its entirety. Technical Field

[0002] The following relates to wireless communications, including reporting the quantity of transmit antennas for wireless communications. Background Art

[0003] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, and so on. These systems may be capable of supporting 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 (such as Long - Term Evolution (LTE) systems, LTE - Advanced (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 FDMA (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, each of which supports wireless communication for communication devices, which may be referred to as User Equipment (UE).

[0004] In some systems, a UE may measure reference signals from network entities to determine Channel State Information (CSI) parameters. The UE may send a CSI report to a network entity to indicate the CSI parameters, and the network entity may perform a downlink transmission to the UE based on the reported CSI parameters. Summary of the Invention

[0005] The described techniques relate to improved methods, systems, devices, and apparatuses for supporting reporting of the number of transmit antennas for wireless communication. For example, the described techniques enable a network entity to send control signaling to a user equipment (UE) to indicate the number of transmit antennas at the network entity. The number of transmit antennas can include antennas (e.g., antenna elements, antenna arrays, antenna ports, etc.) that are activated at the network entity for downlink communication with the UE. The UE can determine a set of one or more channel state information (CSI) parameters based on the number of transmit antennas at the network entity. For example, the UE can determine a precoding matrix indicator (PMI), a rank, a modulation and coding scheme (MCS), or any combination thereof for receiving a downlink transmission based on the number of transmit antennas. Additionally or alternatively, the UE can select a demodulator to be used for demodulating a downlink transmission based on the number of transmit antennas. The UE can send a CSI report to the network entity to indicate the set of one or more CSI parameters. The UE and the network entity can communicate according to the CSI parameters indicated via the CSI report.

[0006] A method for wireless communication at a UE is described. The method can include: receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas that are activated for downlink transmission to the UE; sending a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0007] An apparatus for wireless communication at a UE is described. The apparatus can include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions can be executable by the processor to cause the apparatus to: receive control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas that are activated for downlink transmission to the UE; send a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and communicate with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0008] Describes another apparatus for wireless communication at a UE. The apparatus may include: means for receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE; means for transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and means for communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0009] 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: receive control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE; transmit a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and communicate with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0010] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving control signaling may include operations, features, means, or instructions for: receiving a set of multiple control messages, where a first control message in the set of multiple control messages indicates the number of transmit antennas that may be activated at a network entity at a first time, and where one or more other control messages in the set of multiple control messages indicate one or more other numbers of transmit antennas that may be activated at the network entity at one or more other times different from the first time.

[0011] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving a set of multiple control messages may include operations, features, means, or instructions for: receiving the set of multiple control messages periodically, where each of the set of multiple control messages indicates the corresponding number of transmit antennas that may be activated at the network entity during a corresponding time period associated with the periodicity of the set of multiple control messages.

[0012] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving a set of multiple control messages may include operations, features, means, or instructions for: receiving the set of multiple control messages non-periodically or periodically, where one or more of the set of multiple control messages indicate corresponding changes in the number of transmit antennas that may be activated at the network entity.

[0013] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving control signaling may include operations, features, components, or instructions for: receiving downlink control information (DCI) indicating the number of transmit antennas.

[0014] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, receiving control signaling may include operations, features, components, or instructions for: receiving radio resource control (RRC) signaling indicating the number of transmit antennas.

[0015] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: switching from a first demodulator in a set of multiple demodulators of a UE to a second demodulator in the set of multiple demodulators based on the indicated number of transmit antennas.

[0016] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: identifying the number of spatial streams associated with a downlink transmission; selecting a second demodulator from a set of multiple demodulators of a UE for demodulating the downlink transmission based on a relationship between the indicated number of transmit antennas and the number of spatial streams associated with the downlink transmission, wherein switching from the first demodulator to the second demodulator may be based on the selection of the second demodulator; receiving the downlink transmission; and demodulating the downlink transmission using the selected demodulator.

[0017] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, each demodulator in a set of multiple demodulators of a UE may be associated with a respective demodulation complexity, and the methods, apparatuses, and non-transitory computer-readable media may include further operations, features, components, or instructions for: determining that the indicated number of transmit antennas may be at least a threshold number or a threshold ratio greater than the number of spatial streams associated with a downlink transmission; and selecting a second demodulator associated with a second complexity based on the determination, the second complexity being less than a first complexity associated with the first demodulator and one or more other complexities associated with one or more other demodulators in the set of multiple demodulators, wherein switching from the first demodulator to the second demodulator may be based on the selection of the second demodulator.

[0018] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: detecting a change in one or more channel parameters associated with communication between a UE and a network entity; and transmitting a second CSI report in response to detecting the change to indicate a second set of one or more CSI parameters, wherein a difference between the set of one or more CSI parameters and the second set of one or more CSI parameters may be based on the number of indicated antennas at the network entity and the change in the one or more channel parameters.

[0019] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: determining the set of one or more CSI parameters based on conditions at the UE and the number of indicated transmit antennas at the network entity, wherein a value of each CSI parameter in the set of one or more CSI parameters may be related to the number of transmit antennas at the network entity.

[0020] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the set of one or more CSI parameters includes a PMI, a rank, an MCS, or any combination thereof for receiving a downlink transmission.

[0021] A method for wireless communication at a network entity is described. The method may include: transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE; receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the number of indicated transmit antennas at the network entity; and communicating with the UE based on the set of one or more CSI parameters indicated via the CSI report.

[0022] An apparatus for wireless communication at a network entity is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: transmit control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE; receive a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the number of indicated transmit antennas at the network entity; and communicate with the UE based on the set of one or more CSI parameters indicated via the CSI report.

[0023] Describes another apparatus for wireless communication at a network entity. The apparatus may include: means for sending control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE; means for receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and means for communicating with the UE based on the set of one or more CSI parameters indicated via the CSI report.

[0024] Describes a non-transitory computer-readable medium storing code for wireless communication at a network entity. The code may include instructions executable by a processor to: send control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE; receive a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity; and communicate with the UE based on the set of one or more CSI parameters indicated via the CSI report.

[0025] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, sending the control signaling may include operations, features, means, or instructions for: sending a set of multiple control messages, wherein a first control message in the set of multiple control messages indicates the number of transmit antennas that may be activated at the network entity at a first time, and wherein one or more other control messages in the set of multiple control messages indicate one or more other numbers of transmit antennas that may be activated at the network entity at one or more other times different from the first time.

[0026] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, sending the set of multiple control messages may include operations, features, means, or instructions for: periodically sending the set of multiple control messages, wherein each of the set of multiple control messages indicates the corresponding number of transmit antennas that may be activated at the network entity during a corresponding time period associated with the periodicity of the set of multiple control messages.

[0027] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, sending a set of multiple control messages may include operations, features, components, or instructions for: determining a change in the number of transmit antennas that can be activated at the network entity and sending a control message in the set of multiple control messages to indicate the change in the number of transmit antennas, wherein the set of multiple control messages may be sent aperiodically or periodically, and wherein one or more of the set of multiple control messages indicate corresponding changes in the number of transmit antennas at the network entity.

[0028] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, sending control signaling may include operations, features, components, or instructions for: sending DCI indicating the number of transmit antennas.

[0029] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, sending control signaling may include operations, features, components, or instructions for: sending RRC signaling indicating the number of transmit antennas.

[0030] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may further include operations, features, components, or instructions for: receiving a second CSI report indicating a second set of one or more CSI parameters after receiving a CSI report, wherein the difference between the set of one or more CSI parameters indicated via the CSI report and the second set of one or more CSI parameters indicated via the second CSI report may be based on a change in the number of antennas at the network entity and one or more channel parameters associated with the communication between the network entity and the UE; and sending a second downlink transmission based on the second set of one or more CSI parameters indicated via the second CSI report.

[0031] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the value of each CSI parameter in the set of one or more CSI parameters may be related to the number of transmit antennas at the network entity.

[0032] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the set of one or more CSI parameters includes a PMI, rank, MCS, or any combination thereof for sending a downlink transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 Examples of wireless communication systems that illustrate support for reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure are shown.

[0034] Figure 2Illustrates an example of a network architecture that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0035] Figure 3 Illustrates an example of a wireless communication system that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0036] Figure 4 Illustrates an example of a process flow that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0037] Figure 5 and Figure 6 Illustrates a block diagram of a device that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0038] Figure 7 Illustrates a block diagram of a communication manager that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0039] Figure 8 Illustrates a diagram of a system that includes a device that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0040] Figure 9 and Figure 10 Illustrates a block diagram of a device that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0041] Figure 11 Illustrates a block diagram of a communication manager that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0042] Figure 12 Illustrates a diagram of a system that includes a device that supports reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure.

[0043] Figures 13 to 16 Shows a flowchart of a method that illustrates supporting reporting the number of transmit antennas for wireless communication according to one or more aspects of the present disclosure. Detailed Description

[0044] In some wireless communication systems, a UE may measure reference signals from network entities to determine channel state information (CSI) parameters. The CSI parameters may include modulation and coding schemes (MCSs) supported by the UE, ranks (e.g., number of beams) supported by the UE, precoding matrix indicators (PMIs), or any combination thereof. In some examples, the UE may send a CSI report indicating the CSI parameters, and the network entity may perform a downlink transmission to the UE based on the reported CSI parameters. Thus, the UE may determine the number of downlink beams (also referred to as spatial streams) for sending a given downlink message to the UE. However, the UE may not know the number of transmit antennas at the network entity that may be used to send the downlink message to the UE.

[0045] The techniques described herein enable a network entity to indicate, via control signaling, the number of transmit antennas at the network entity that are used to send a downlink message to a UE. In some cases, the control signaling may be downlink control information (DCI), radio resource control (RRC) configuration, or some other control signaling. The number of antennas indicated via the control signaling may correspond to the number of transmit antenna elements, arrays, or sub-arrays of an antenna panel at the network entity that may be activated for downlink transmission to the UE. Thereby, the UE may use the indicated number of antennas to reduce power consumption and improve CSI report accuracy.

[0046] The UE may additionally or alternatively use the indicated number of transmit antennas to reduce the complexity associated with demodulating the downlink transmission, improve CSI report accuracy, or both. For example, the UE may select one demodulator from a plurality of demodulators at the UE based on the number of transmit antennas. In cases where the number of transmit antennas may be relatively high, the UE may select a demodulator associated with relatively low complexity to reduce power consumption while maintaining throughput. Additionally or alternatively, the UE may calculate and report a rank, MCS, or PMI based on the number of transmit antennas at the network entity, which may improve accuracy and reliability.

[0047] Aspects of the present disclosure are first described in the context of a wireless communication system. Additional aspects of the present disclosure are described with reference to wireless communication systems and process flows. The various aspects of the present disclosure are further illustrated and described by and with reference to apparatus diagrams, system diagrams, and flowcharts related to reporting the number of transmit antennas for wireless communication.

[0048] Figure 1An example of a wireless communication system 100 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 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 LTE-Advanced (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating in accordance with other systems and radio technologies including future systems and radio technologies not explicitly mentioned herein.

[0049] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100 and may include devices in various forms or having different capabilities. In various examples, the network entities 105 may be referred to as network elements, mobility elements, radio access network (RAN) nodes, or network equipment, among other designations. In some examples, the network entities 105 and the UEs 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UEs 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UEs 115 may support signal communication in accordance with one or more radio access technologies (RATs).

[0050] 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 stationary and mobile at different times. The UEs 115 may be devices in various forms or having different capabilities. Figure 1 Some example UEs 115 are illustrated. The UEs 115 described herein may be capable of supporting communication with various types of devices, such as other UEs 115 or network entities 105, as Figure 1 shown.

[0051] As described herein, a node of the wireless communication system 100 (which may be referred to as a network node or a wireless node) may be a network entity 105 (e.g., any network entity described herein), a UE 115 (e.g., any UE described herein), a network controller, a device, an equipment, a computing system, one or more components, or another suitable processing entity configured to perform any of the techniques described herein. For example, the node may be a UE 115. As another example, the node may be a network entity 105. As yet another example, a first node may be configured to communicate with a second node or a third node. In one aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a UE 115. In another aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a network entity 105. In other aspects of this example, the first node, the second node, and the third node may be different from these examples. Similarly, references to UE 115, network entity 105, device, equipment, computing system, etc. may include the disclosure of UE 115, network entity 105, device, equipment, computing system, etc. as nodes. For example, the disclosure that a UE 115 is configured to receive information from a network entity 105 also discloses that a first node is configured to receive information from a second node.

[0052] In some examples, the network entity 105 may communicate with the core network 130 or with each other or both. For example, the network entity 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3, or other interface protocols). In some examples, the network entity 105 may communicate with each other directly (e.g., directly between the network entities 105) or indirectly (e.g., via the core network 130) via the backhaul communication links 120 (e.g., according to X2, Xn, or other interface protocols). In some examples, the network entity 105 may communicate with each other via a midhaul communication link 162 (e.g., according to a midhaul interface protocol) or a fronthaul communication link 168 (e.g., according to a fronthaul interface protocol) or any combination thereof. The backhaul communication link 120, the midhaul communication link 162, or the fronthaul communication link 168 may be or include one or more wired links (e.g., electrical links, optical fiber links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. The UE 115 may communicate with the core network 130 via a communication link 155.

[0053] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., transceiver base station, radio base station, NR base station, access point, radio transceiver, Node B, evolved Node B (eNB), next generation Node B or gigabit Node B (either of which may be referred to as gNB), 5G NB, next generation eNB (ng-eNB), home Node B, home evolved Node B or other suitable terms). In some examples, the network entity 105 (e.g., base station 140) may be implemented in an integrated (e.g., monolithic, stand-alone) base station architecture that may be configured to utilize a protocol stack physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as base station 140).

[0054] In some examples, the network entity 105 may be implemented in a disaggregated architecture (e.g., disaggregated base station architecture, disaggregated RAN architecture) that may be configured to utilize a protocol stack physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or virtualized RAN (vRAN) (e.g., cloud RAN (C-RAN)). For example, the network entity 105 may include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., near real-time RIC (near RT RIC), non-real-time RIC (non RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, intelligent radio head, remote radio head (RRH), remote radio unit (RRU), or transmit receive point (TRP). One or more components of the network entity 105 in a disaggregated RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some examples, one or more network entities 105 of a disaggregated RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0055] The functional split between the CU 160, DU 165, and RU 170 is flexible and can support different functions, depending on which functions are performed at the CU 160, DU 165, or RU 170 (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof). For example, a functional split of the protocol stack can be employed between the CU 160 and the DU 165 such that the CU 160 can support one or more layers of the protocol stack and the DU 165 can support one or more different layers of the protocol stack. In some examples, the CU 160 can host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functions and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 can be connected to one or more DU 165s or RU 170s, and one or more DU 165s or RU 170s can host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, media access control (MAC) layer) functions and signaling, and can each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack can be employed between the DU 165 and the RU 170 such that the DU 165 can support one or more layers of the protocol stack and the RU 170 can support one or more different layers of the protocol stack. The DU 165 can support one or more different cells (e.g., via one or more RU 170s). In some cases, the functional split between the CU 160 and the DU 165 or between the DU 165 and the RU 170 can be within a protocol layer (e.g., some functions of a protocol layer can be performed by one of the CU 160, DU 165, or RU 170, while other functions of that protocol layer are performed by a different one of the CU 160, DU 165, or RU 170). The CU 160 can be further functionally split into a CU control plane (CU-CP) and a CU user plane (CU-UP) function. The CU 160 can be connected to one or more DU 165s via an intermediate transport communication link 162 (e.g., F1, F1-c, F1-u), and the DU 165 can be connected to one or more RU 170s via a fronthaul communication link 168 (e.g., open fronthaul (FH) interface). In some examples, the intermediate transport communication link 162 or the fronthaul communication link 168 can be implemented according to the interfaces (e.g., channels) between the layers of the protocol stack, which are supported by the corresponding network entities 105 communicating via such communication links.

[0056] In some wireless communication systems (e.g., wireless communication system 100), the infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement a wired backhaul connection, thereby providing an IAB network architecture (e.g., to a core network 130). In some cases, in an IAB network, one or more network entities 105 (e.g., IAB node 104) may be partially controlled by each other. One or more IAB nodes 104 may be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 may be partially controlled by one or more CUs 160 associated with a donor network entity 105 (e.g., donor base station 140). One or more donor network entities 105 (e.g., IAB donors) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via the supported access and backhaul links (e.g., backhaul communication link 120). An IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a DU 165 of a coupled IAB donor. The IAB-MT may include a separate antenna set for relaying communication with a UE 115 or may share the same antenna (e.g., of an RU 170 of the IAB node 104) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some examples, the IAB node 104 may include a DU 165 that supports communication links with additional entities (e.g., IAB nodes 104, UEs 115) within a relay chain or configuration (e.g., downstream) of the access network. In such cases, one or more components of a split RAN architecture (e.g., one or more IAB nodes 104 or components of an IAB node 104) may be configured to operate according to the techniques described herein.

[0057] For example, the access network (AN) or RAN may include communication between an access node (e.g., an IAB donor), an IAB node 104, and one or more UEs 115. The IAB donor may facilitate a connection between the core network 130 and the AN (e.g., via a wired or wireless connection to the core network 130). That is, the IAB donor may refer to a RAN node having a wired or wireless connection to the core network 130. The IAB donor may include a CU 160 and at least one DU 165 (e.g., and an RU 170), where the CU 160 may communicate with the core network 130 via an interface (e.g., a backhaul link). The IAB donor and the IAB node 104 may communicate via an F1 interface according to a protocol that defines signaling messages (e.g., the F1 AP protocol). Additionally or alternatively, the CU 160 may communicate with the core network via an interface (which may be an example of a part of the backhaul link), and may communicate with other CUs 160 (e.g., CUs 160 associated with alternative IAB hosts) via an Xn-C interface (which may be an example of a part of the backhaul link).

[0058] The IAB node 104 may refer to a RAN node that provides IAB functionality (e.g., access for the UE 115, wireless self-backhaul capabilities, etc.). The DU 165 may act as a distributed scheduling node towards the child nodes associated with the IAB node 104, and the IAB-MT may act as a scheduled node towards the parent node associated with the IAB node 104. That is, the IAB donor may be referred to as a parent node that communicates with one or more child nodes (e.g., the IAB donor may relay transmissions for the UE through one or more other IAB nodes 104). Additionally or alternatively, depending on the relay chain or configuration of the AN, the IAB node 104 may also be referred to as a parent node or a child node of other IAB nodes 104. Thus, the IAB-MT entity of the IAB node 104 may provide a Uu interface for the child IAB node 104 to receive signaling from the parent IAB node 104, and the DU interface (e.g., DU 165) may provide a Uu interface for the parent IAB node 104 to signal to the child IAB node 104 or the UE 115.

[0059] For example, the IAB node 104 may be referred to as a parent node that supports communication for a child IAB node or as a child node associated with an IAB donor or both. The IAB donor may include a CU 160 having a wired or wireless connection to the core network 130 (e.g., a fronthaul communication link 120) and may act as the parent node of the IAB node 104. For example, the DU 165 of the IAB donor may relay transmissions to the UE 115 via the IAB node 104, or may signal transmissions directly to the UE 115, or both. The CU 160 of the IAB donor may signal communication link establishment to the IAB node 104 via the F1 interface, and the IAB node 104 may schedule transmissions (e.g., transmissions relayed from the IAB donor to the UE 115) via the DU 165. That is, data may be relayed to and from the IAB node 104 via signaling over the NR Uu interface to the MT of the IAB node 104. Communication with the IAB node 104 may be scheduled by the DU 165 of the IAB donor, and communication with the IAB node 104 may be scheduled by the DU 165 of the IAB node 104.

[0060] In the context where the techniques described herein are applied to a split RAN architecture, one or more components of the split RAN architecture may be configured to support reporting the number of transmit antennas for wireless communication as described herein. For example, some operations described as being performed by the UE 115 or the network entity 105 (e.g., the base station 140) may additionally or alternatively be performed by one or more components of the split RAN architecture (e.g., the IAB node 104, the DU 165, the CU 160, the RU 170, the RIC 175, the SMO 180).

[0061] The UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device or some other suitable term, where "device" may also be referred to as a unit, a station, a terminal, or a client, etc. The UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, the UE 115 may include or may be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in various objects such as appliances or vehicles, meters, etc.

[0062] The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115 that may sometimes act as relays, as well as network entities 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, relay base stations, etc., asFigure 1 as shown

[0063] UE 115 and network entity 105 may communicate wirelessly with each other via one or more communication links 125 (e.g., access links) using resources associated with one or more carriers. The term "carrier" may refer to a set of RF spectrum resources having a defined physical layer structure for supporting communication link 125. For example, a carrier for communication link 125 may include a portion (e.g., bandwidth part (BWP)) of an RF spectrum band operating 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 carrier operation, user data, or other signaling. Wireless communication system 100 may support communication with UE 115 using carrier aggregation or multi-carrier operation. According to a carrier aggregation configuration, UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between network entity 105 and other devices may refer to communication between these devices and any part (e.g., entity, sub-entity) of network entity 105. For example, the terms "transmit", "receive", or "communicate" when referring to network entity 105 may refer to any part of network entity 105 of the RAN (e.g., base station 140, CU 160, DU 165, RU 170) communicating with another device (e.g., directly or via one or more other network entities 105).

[0064] In some examples, such as in a carrier aggregation configuration, a carrier may also have acquisition signaling or control signaling for coordinating the operation of other carriers. A carrier may be associated with a frequency channel (e.g., evolved universal mobile telecommunications system terrestrial radio access (E-UTRA) absolute RF channel number (EARFCN)) and may be identified according to a channel raster for discovery by UE 115. A carrier may operate in independent mode, in which case initial acquisition and connection may be performed by UE 115 via the carrier, or a carrier may operate in non-independent mode, in which case the connection is anchored using a different carrier (e.g., different carriers of the same or different radio access technologies).

[0065] The communication link 125 shown in the wireless communication system 100 may include a downlink transmission (e.g., forward link transmission) from the network entity 105 to the UE 115, an uplink transmission (e.g., reverse link transmission) from the UE 115 to the network entity 105, or other transmission configurations such as both. A carrier may carry downlink communication or uplink communication (e.g., in FDD mode), or may be configured to carry both downlink communication and uplink communication (e.g., in TDD mode).

[0066] A carrier may be associated with a specific bandwidth of the RF 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 a set of bandwidths of carriers of a particular radio access technology (e.g., 1.4 megahertz (MHz), 3 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, or 80 MHz). Devices of the wireless communication system 100 (e.g., the network entity 105, the UE 115, or both) may have a hardware configuration that supports communication using a particular carrier bandwidth, or may be configurable to support communication using one of a set of carrier bandwidths. In some examples, the wireless communication system 100 may include a network entity 105 or a UE 115 that supports concurrent communication using carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate using a portion (e.g., subband, BWP) or all of the carrier bandwidth.

[0067] The signal waveform transmitted via a carrier may include multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques 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 refer to the resource of one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, in which case the symbol period and the subcarrier spacing may be 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 decoding rate of the modulation scheme, or both), such that a relatively high number of resource elements (e.g., during the transmission duration) and a relatively high-order modulation scheme may correspond to a relatively high communication rate. Wireless communication resources may refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layer or beam), and the use of multiple spatial resources may increase the data rate or data integrity for communication with the UE 115.

[0068] One or more parameter sets may be supported for a carrier, and the parameter set may include a subcarrier spacing ( ( ) and a cyclic prefix. A carrier can be divided into one or more BWPs with the same or different parameter sets. In some examples, UE 115 can be configured with multiple BWPs. In some examples, a single BWP of a carrier can be active at a given time, and the communication of UE 115 can be restricted to one or more active BWPs.

[0069] A time interval for a network entity 105 or UE 115 can be expressed as a multiple of a basic time unit, and the basic time unit can refer to, for example, a sampling period seconds, for which can represent the supported subcarrier spacing, and can represent the 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).

[0070] 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 certain 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 certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended to each symbol period). In some wireless communication systems 100, a time slot can be further divided into a plurality of mini-slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period can be associated with one or more (e.g., number of) sampling periods. The duration of a symbol period can depend on the subcarrier spacing or the operating frequency band.

[0071] A subframe, time slot, mini-slot or symbol can be the smallest scheduling unit of the wireless communication system 100 (e.g., in the time domain), 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 a burst of shortened TTIs (sTTIs)).

[0072] According to various techniques, carriers can be used to multiplex physical channels for communication. 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 for signaling via a downlink carrier. The control region of a physical control channel (e.g., a control resource set (CORESET)) can be defined by a set of symbol periods and can extend across the system bandwidth of a carrier or a subset of that system bandwidth. One or more control regions (e.g., CORESETs) can be configured for a set 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 in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate can refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with the coded information for a control information format with a given payload size. The search space sets can include: a common search space set configured to transmit control information to a plurality of UEs 115, and a UE-specific search space set for transmitting control information to a specific UE 115.

[0073] The network entity 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 the network entity 105 (e.g., using 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 cell identifier). In some examples, a cell can also refer to a coverage area 110 or a portion of the coverage area 110 (e.g., a sector) on which the logical communication entity operates. Depending on various factors such as the capabilities of the network entity 105, the range of such cells can be from a smaller area (e.g., a structure, a subset of a structure) to a larger area. For example, a cell can be or can include a building, a subset of a building, or an external space between or overlapping with the coverage areas 110, etc.

[0074] Macro cells generally cover a relatively large geographical area (e.g., with a radius of several kilometers) and can allow unrestricted access to UEs 115 that have a service subscription with the network provider that supports the macro cell. Compared to macro cells, small cells can be associated with lower power network entities 105 (e.g., lower power base stations 140), and small cells can operate using the same or different (e.g., licensed, unlicensed) frequency bands as macro cells. Small cells can provide unrestricted access to UEs 115 that have a service subscription with the network provider, or can provide restricted access to UEs 115 that are associated with the small cell (e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 associated with users in a home or office). The network entity 105 can support one or more cells and can also use one or more component carriers to support communication via the one or more cells.

[0075] 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)).

[0076] In some examples, the network entity 105 (e.g., base station 140, RU 170) can be movable and thus provide communication coverage for a moving coverage area 110. In some examples, different coverage areas 110 associated with different technologies can overlap, but different coverage areas 110 can be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies can be supported by different network entities 105. The wireless communication system 100 can include, for example, a heterogeneous network in which different types of network entities 105 use the same or different radio access technologies to provide coverage for various coverage areas 110.

[0077] The wireless communication system 100 can support synchronous or asynchronous operation. For synchronous operation, the network entities 105 (e.g., base stations 140) can have similar frame timings, and transmissions from different network entities 105 can be approximately aligned in time. For asynchronous operation, the network entities 105 can have different frame timings, and in some examples, transmissions from different network entities 105 can be misaligned in time. The techniques described herein can be used for synchronous operation or asynchronous operation.

[0078] Some UEs 115 (such as 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 network entity 105 (e.g., base station 140) without human intervention. In some examples, M2M communication or MTC can include communication from devices integrated with sensors or meters to measure or acquire information and relay such information to a central server or application that uses the information or presents the information to a person interacting 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, equipment monitoring, healthcare monitoring, wildlife monitoring, weather and geographical event monitoring, queue management and tracking, remote security sensing, physical access control, and transaction-based commercial charging.

[0079] Some UEs 115 can be configured to operate in an operation mode that reduces power consumption, such as half-duplex communication (e.g., a mode that supports one-way communication via transmission or reception but does not transmit and receive concurrently). In some examples, half-duplex communication can be performed at a reduced peak rate. Other energy-saving technologies for UEs 115 include: entering a power-saving deep sleep mode when not participating in active communication, operating using limited bandwidth (e.g., according to narrowband communication), or a combination of these technologies. For example, some UEs 115 can be configured to operate using a narrowband protocol type that is associated with a defined portion or range within a carrier, within a guard band of the carrier, or outside the carrier (e.g., a set of subcarriers or resource blocks (RBs)).

[0080] Wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC). UEs 115 can be designed to support ultra-reliable or low-latency or critical functions. Ultra-reliable communication can include private communication or group communication and can be supported by one or more services (such as push-to-talk, video, or data). Support for ultra-reliable, low-latency functions can include prioritizing services, and such services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency can be used interchangeably herein.

[0081] In some examples, the UE 115 may be configured to support direct communication with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P), D2D, or sidelink protocol). In some examples, one or more UEs 115 performing D2D communication in a group may be within the coverage area 110 of a network entity 105 (e.g., base station 140, RU 170), and this network entity may support aspects of such D2D communication configured (e.g., scheduled) by the network entity 105. In some examples, one or more UEs 115 in such a group may be outside the coverage area 110 of the network entity 105, or may otherwise be unable or not configured to receive transmissions from the network entity 105. In some examples, a group of UEs 115 communicating via D2D communication may support a one-to-many (1:M) system, where each UE 115 transmits to each of the other UEs 115 in the group. In some examples, the network entity 105 may facilitate the scheduling of resources for D2D communication. In some other examples, D2D communication may be performed between UEs 115 without involving the network entity 105.

[0082] In some systems, the D2D 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 roadside units), or communicate with the network via one or more network nodes (e.g., network entity 105, base station 140, RU 170) using vehicle-to-network (V2N) communication, or both.

[0083] The core network 130 can provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 can be an evolved packet core (EPC) or a 5G core (5GC), which can include at least one control plane entity for managing access and mobility (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) and at least one user plane entity for routing packets or interconnecting to external networks (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 can manage non-access stratum (NAS) functions, such as the mobility, authentication, and bearer management of the UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets can be passed through the user plane entity, which can provide IP address allocation and other functions. The user plane entity can be connected to the IP services 150 of one or more network operators. The IP services 150 can include access to the Internet, an intranet, an IP multimedia subsystem (IMS), or packet switched streaming services.

[0084] The wireless communication system 100 can operate using one or more frequency bands that can be 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, in terms of length, the wavelength range is from approximately one decimeter to one meter. UHF waves can be blocked or redirected by buildings and environmental features (which can be referred to as clusters), but these waves can be sufficient to penetrate structures so that a macro cell can serve a UE 115 located indoors. Compared to communication using smaller frequencies and longer wavelengths in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz, communication using UHF waves can be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers).

[0085] The wireless communication system 100 may also operate using the Super High Frequency (SHF) region (also known as the centimeter band) in the range of 3 GHz to 30 GHz or using the Extremely High Frequency (EHF) region of the spectrum (e.g., 30 GHz to 300 GHz) (also known as the millimeter band). In some examples, the wireless communication system 100 may support millimeter wave (mmW) communication between the UE 115 and network entities 105 (e.g., base station 140, RU 170), and the EHF antennas of the corresponding devices may be smaller and closer spaced than UHF antennas. In some examples, such techniques may facilitate the use of antenna arrays within a device. However, the propagation of EHF transmissions may be affected by greater attenuation and shorter range than SHF or UHF transmissions. The techniques disclosed herein may be employed across transmissions using one or more different frequency regions, and the use of frequency bands designated across these frequency regions may vary by country or regulatory body.

[0086] The wireless communication system 100 may utilize licensed and unlicensed RF spectrum bands. For example, the wireless communication system 100 may use an unlicensed band (such as the 5 GHz Industrial, Scientific and Medical (ISM) band) to employ Licensed-Assisted Access (LAA), Long-Term Evolution Unlicensed (LTE-U) radio access technology, or NR technology. When operating using an unlicensed RF spectrum band, devices such as network entities 105 and UE 115 may employ carrier sensing for collision detection and avoidance. In some examples, the operation using an unlicensed band may be combined with a component carrier operating using a licensed band based on a carrier aggregation configuration (e.g., LAA). The operation using unlicensed spectrum may include downlink transmissions, uplink transmissions, peer-to-peer (P2P) transmissions, device-to-device (D2D) transmissions, and so on.

[0087] The network entity 105 (e.g., base station 140, RU 170) or 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 network entity 105 or 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 network entity 105 may be located at different geographical locations. The network entity 105 may include an antenna array having a set of antenna ports arranged in multiple rows and columns that the network entity 105 may use to support beamforming for communication with the UE 115. Similarly, the UE 115 may include one or more antenna arrays, which may support various MIMO or beamforming operations. Additionally or alternatively, an antenna panel may support RF beamforming for signals transmitted via an antenna port.

[0088] Network entity 105 or UE 115 may use MIMO communication to utilize multipath signal propagation and improve spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may be transmitted, for example, by the transmitting device via different antennas or different combinations of antennas. Similarly, the multiple signals may be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry information associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). The different spatial layers may 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.

[0089] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., network entity 105, UE 115) to shape or steer an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals conveyed via the antenna elements of an antenna array such that some signals propagating along a particular direction relative to the antenna array experience constructive interference while other signals experience destructive interference. The adjustment of the signals conveyed via the antenna elements may 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 these antenna elements may be defined by a set of beamforming weights associated with a particular direction (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other direction).

[0090] Network entity 105 or UE 115 may use beam scanning techniques as part of a beamforming operation. For example, network entity 105 (e.g., base station 140, RU 170) may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted by network entity 105 multiple times in different directions. For example, network entity 105 may transmit signals according to different sets of beamforming weights associated with different transmission directions. The transmissions along different beam directions may be used to identify (e.g., by the transmitting device such as network entity 105, or by the receiving device such as UE 115)) the beam directions for later transmission or reception by network entity 105.

[0091] Some signals, such as data signals associated with a particular receiving device, may be transmitted by a transmitting device (e.g., transmitting network entity 105, transmitting UE 115) along a single beam direction (e.g., a direction associated with a receiving device such as receiving network entity 105 or receiving UE 115). In some examples, the beam direction associated with transmission along a single beam direction may be determined based on signals transmitted along one or more beam directions. For example, UE 115 may receive one or more of the signals transmitted by network entity 105 in different directions, and may report to network entity 105 an indication of the signal that UE 115 receives with the highest signal quality or other acceptable signal quality.

[0092] In some examples, transmissions performed by a device (e.g., by network entity 105 or UE 115) may be carried out using multiple beam directions, and the device may use a combination of digital precoding or beamforming to generate a combined beam for transmission (e.g., from network entity 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 set of beams across the system bandwidth or one or more sub-bands. Network entity 105 may transmit reference signals (e.g., cell-specific reference signal (CRS), CSI reference signal (CSI-RS)), which may or may not be precoded. UE 115 may provide feedback for beam selection, which may be 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 network entity 105 (e.g., base station 140, RU 170) in one or more directions, UE 115 may use similar techniques for transmitting signals multiple times in different directions (e.g., for identifying beam directions used by UE 115 for subsequent transmission or reception), or for transmitting signals in a single direction (e.g., for transmitting data to a receiving device).

[0093] A receiving device (e.g., UE 115) may perform receiving operations according to multiple receiving configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from a receiving device (e.g., network entity 105). For example, the receiving device may perform receiving according to multiple receiving directions by: receiving via different antenna sub-arrays, processing the received signals according to different antenna sub-arrays, receiving according to different sets of receive beamforming weights (e.g., different directional listening weight sets) applied to the signals received at multiple antenna elements of an antenna array, or processing the received signals according to different sets of receive beamforming weights applied to the signals received at multiple antenna elements of an antenna array, any of which may be referred to as "listening" according to different receiving configurations or receiving directions. In some examples, the receiving device may use a single receiving configuration to receive along a single beam direction (e.g., when receiving a data signal). The single receiving configuration may be aligned along a beam direction determined based on listening according to different receiving configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0094] The wireless communication system 100 may be a packet-based network operating according to a hierarchical protocol stack. In the user plane, communication at the bearer or PDCP layer may be IP-based. The RLC layer may perform packet segmentation and reassembly for conveyance via logical channels. The MAC layer may perform priority handling and multiplexing from logical channels into transport channels. The MAC layer may also implement error detection techniques, error correction techniques, or both to support retransmission to improve link efficiency. In the control plane, the RRC layer may provide establishment, configuration, and maintenance of an RRC connection that supports radio bearers for user plane data between the UE 115 and the network entity 105 or the core network 130. The PHY layer may map transport channels to physical channels.

[0095] UE 115 and network entity 105 may support retransmission of data to increase the likelihood of successful data reception. Hybrid Automatic Repeat reQuest (HARQ) feedback is a technique for increasing the likelihood of correctly receiving data via a communication link (e.g., communication link 125, D2D communication link 135). 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 under poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, the device may support same-slot HARQ feedback, in which case the device may provide HARQ feedback in a particular slot for data received in previous symbols in that slot. In some other examples, the device may provide HARQ feedback in a subsequent slot or according to some other time interval.

[0096] In some examples of the wireless communication system 100, UE 115 may measure reference signals from network entity 105 to determine CSI parameters. The CSI parameters may include the MCS supported by UE 115, the rank supported by UE 115 (e.g., the number of beams), PMI, or any combination thereof. In some examples, UE 115 may send a CSI report indicating the CSI parameters, and network entity 105 may perform a downlink transmission to UE 115 based on the reported CSI parameters. Thus, UE 115 may determine the number of downlink beams (also referred to as spatial streams) for sending a given downlink message to UE 115. However, UE 115 may not know the number of transmit antennas at network entity 105 that may be used to send the downlink message to the UE.

[0097] The techniques described herein enable network entity 105 to indicate, via control signaling, the number of transmit antennas at the network entity for sending a downlink message to the UE. In some cases, the control signaling may be DCI, RRC configuration, or some other control signaling. The number of transmit antennas indicated via the control signaling may correspond to the number of transmit antenna elements, arrays, or sub-arrays of an antenna panel at the network entity that may be activated for downlink transmission to UE 115. Thereby, UE 115 may use the indicated number of antennas to reduce power consumption and improve CSI report accuracy.

[0098] The UE 115 may additionally or alternatively use the indicated number of transmit antennas to reduce the complexity associated with demodulating downlink transmissions, improve CSI reporting accuracy, or both. For example, the UE 115 may select one demodulator from a plurality of demodulators at the UE 115 based on the number of transmit antennas. In cases where the number may be relatively high, the UE 115 may select a demodulator associated with relatively low complexity to reduce power consumption while maintaining throughput. Additionally or alternatively, the UE 115 may calculate and report a rank, MCS, or PMI based on the number of transmit antennas at the network entity 105, which may improve the accuracy and reliability of communication between the UE 115 and the network entity 105.

[0099] Figure 2 An example of a network architecture 200 (e.g., a split base station architecture, a split RAN architecture) that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure is illustrated. The network architecture 200 may illustrate an example for implementing one or more aspects of the wireless communication system 100. The network architecture 200 may include one or more CUs 160-a, which may communicate directly with the core network 130-a via a fronthaul communication link 120-a, or indirectly with the core network 130-a through one or more split network entities 105 (e.g., a near RT RIC 175-b via an E2 link or a non-RT RIC 175-a associated with an SMO 180-a (e.g., an SMO framework) or both). The CU 160-a may communicate with one or more DUs 165-a via a respective midhaul communication link 162-a (e.g., an F1 interface). The DU 165-a may communicate with one or more RUs 170-a via a respective fronthaul communication link 168-a. The RU 170-a may be associated with a respective coverage area 110-a and may communicate with the UE 115-a via one or more communication links 125-a. In some implementations, the UE 115-a may be served by multiple RUs 170-a simultaneously.

[0100] Each network entity 105 in the network entity 105 of the network architecture 200 (e.g., CU 160-a, DU 165-a, RU 170-a, non-RT RIC 175-a, near-RT RIC 175-b, SMO 180-a, Open Cloud (O-Cloud) 205, Open eNB (O-eNB) 210) may include one or more interfaces or may be coupled to one or more interfaces configured to receive or transmit signals (e.g., data, information) via a wired or wireless transmission medium. Each network entity 105 or an associated processor (e.g., a controller) that provides instructions to the interfaces of the network entity 105 may be configured to communicate with one or more of the other network entities 105 via the transmission medium. For example, these network entities 105 may include a wired interface configured to receive signals on a wired transmission medium or transmit signals to one or more of the other network entities 105 on the wired transmission medium. Additionally or alternatively, the network entity 105 may include a wireless interface, which may include a receiver, a transmitter, or a transceiver (e.g., an RF transceiver), configured to receive signals on a wireless transmission medium, transmit signals to one or more of the other network entities 105 on the wireless transmission medium, or both.

[0101] In some examples, CU 160-a may host one or more higher-layer control functions. Such control functions may include RRC, PDCP, SDAP, etc. Each control function may be implemented with an interface configured to communicate signals with other control functions hosted by CU 160-a. CU 160-a may be configured to handle user plane functions (e.g., CU-UP), control plane functions (e.g., CU-CP), or a combination thereof. In some examples, CU 160-a may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP units may communicate bidirectionally with the CU-CP units via an interface such as an E1 interface. As needed, CU 160-a may be implemented to communicate with DU 165-a for network control and signaling.

[0102] The DU 165-a may correspond to a logical unit that includes one or more functions (e.g., base station functions, RAN functions) for controlling the operation of one or more RUs 170-a. In some examples, the DU 165-a may at least partially host one or more aspects of the RLC layer, MAC layer, and PHY layer (e.g., high PHY layer, such as modules for FEC encoding and decoding, scrambling, modulation, and demodulation, etc.), at least partially depending on the functional split, such as those defined by the 3rd Generation Partnership Project (3GPP). In some examples, the DU 165-a may also host one or more low PHY layers. Each layer may be implemented using an interface configured to communicate signals with other layers hosted by the DU 165-a or with control functions hosted by the CU 160-a.

[0103] In some examples, the lower layer functions may be implemented by one or more RUs 170-a. For example, an RU 170-a controlled by the DU 165-a may correspond to a logical node that hosts RF processing functions or low PHY layer functions (e.g., performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.) or both, at least partially based on a functional split (such as a lower layer functional split). In such an architecture, the RU 170-a may be implemented to handle over-the-air (OTA) communication with one or more UEs 115-a. In some embodiments, the real-time and non-real-time aspects of the control plane and user plane communication with the RU 170-a may be controlled by the corresponding DU 165-a. In some examples, such a configuration may enable the DU 165-a and CU 160-a to be implemented in a cloud-based RAN architecture (such as a vRAN architecture).

[0104] The SMO 180-a can be configured to support the RAN deployment and provisioning of non-virtualized and virtualized network entities 105. For non-virtualized network entities 105, the SMO 180-a can be configured to support the deployment of dedicated physical resources for RAN coverage requirements, and these dedicated physical resources can be managed via an operation and maintenance interface (e.g., the O1 interface). For virtualized network entities 105, the SMO 180-a can be configured to interact with a cloud computing platform (e.g., the O-Cloud 205) via a cloud computing platform interface (e.g., the O2 interface) to perform network entity lifecycle management (e.g., to instantiate the virtualized network entity 105). Such virtualized network entities 105 can include, but are not limited to, the CU 160-a, the DU 165-a, the RU 170-a, and the near RT RIC 175-b. In some specific implementations, the SMO 180-a can communicate with components configured according to 4G RAN (e.g., via the O1 interface). Additionally or alternatively, in some specific implementations, the SMO 180-a can directly communicate with one or more RUs 170-a via the O1 interface. The SMO 180-a can also include a non-RT RIC 175-a, which is configured to support the functionality of the SMO 180-a.

[0105] The non-RT RIC 175-a can be configured to include logic functions that implement non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI) or machine learning (ML) workflows (including model training and updating, or policy-based steering of applications / features in the near RT RIC 175-b). The non-RT RIC 175-a can be coupled to or communicate with the near RT RIC 175-b (e.g., via the A1 interface). The near RT RIC 175-b can be configured to include logic functions that implement near-real-time control and optimization of RAN elements and resources via data collection and actions on an interface (e.g., via the E2 interface) that connects one or more CUs 160-a, one or more DUs 165-a, or both, and the O-eNB 210 to the near RT RIC 175-b.

[0106] In some examples, to generate an AI / ML model to be deployed in the near-RT RIC 175-b, the non-RT RIC 175-a may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 175-b and may be received at the SMO 180-a or the non-RT RIC 175-a from a non-network data source or from a network function. In some examples, the non-RT RIC 175-a or the near-RT RIC 175-b may be configured to tune RAN behavior or performance. For example, the non-RT RIC 175-a may monitor long-term trends and patterns of performance and employ an AI model or an ML model to perform corrective actions via the SMO 180-a (e.g., via reconfiguration of O1) or via the generation of a RAN management policy such as an A1 policy.

[0107] In some cases, the network architecture 200 may support techniques for a network entity 105 to send control signaling to a UE 115-a to indicate the number of transmit antennas that are activated for downlink communication with the UE 115-a. The number of transmit antennas may include antenna elements, antenna ports, antenna arrays, antenna sub-arrays, or some other type of antenna used by the network entity 105. These amounts of antennas may include antennas located on the same physical component (e.g., the same transmit / receive point (TRP)) of the network entity 105. Additionally or alternatively, these amounts of antennas may be distributed across one or more TRPs, radio heads, or other components of the network entity 105. The UE 115-a may determine one or more CSI parameters (e.g., CSI, rank, PMI, MCS) based on the indicated number of transmit antennas, which may improve the accuracy and reliability of the selected and reported CSI parameters and the corresponding communication. In some examples, the UE 115-a may select one demodulator from a plurality of demodulators at the UE 115-a based on the indicated number of antennas. Thereby, the UE 115-a may reduce power consumption while maintaining the throughput and reliability of the communication. Refer to Figure 3 and Figure 4 , techniques and methods for a network entity 105 to indicate the number of transmit antennas are described in more detail elsewhere in this document.

[0108] Figure 3 FIG. illustrates an example of a wireless communication system 300 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. In some examples, the wireless communication system 300 may implement aspects of the wireless communication system 100 or the network architecture 200, or may be implemented by aspects of such wireless communication systems and network architectures, as referenced in Figure 1 and Figure 2As described. For example, the wireless communication system 300 may include UEs 115-b, 115-c, and network entity 105-a, which may represent examples of the corresponding devices described herein. In this example, network entity 105-a may send an indication of the number of antennas at network entity 105-a, which may improve communication reliability and coordination among the devices in wireless communication system 300.

[0109] Network entity 105-a may include antenna panel 305. Antenna panel 305 may include one or more antennas 310. Antennas 310 may be combined into an antenna array or subarray of antenna panel 305. For example, one or more of antennas 310 may be an example of a portion within antenna panel 305, such as a subarray or array of antennas 310. Antennas 310 may be used by network entity 105-a for transmission, reception, or both for wireless communication. Figure 3 Each of antennas 310 illustrated herein may represent an example of an antenna element, an antenna port, a group of antenna elements, an antenna element array, an antenna element subarray, or any combination thereof, and may be referred to as transmit antennas 310 in some aspects described herein.

[0110] Network entity 105-a may use antennas 310 within antenna panel 305 to transmit and receive wireless communication. When network entity 105-a transmits a downlink transmission 325, antennas 310 of antenna panel 305 may be used to generate or produce one or more beams 315 (e.g., spatial streams), such as beams 315-a, 315-b, 315-c, 315-d, and 315-e. In some examples, a single antenna 310 may produce a single corresponding beam 315, or multiple antennas 310 may produce a single beam 315, or any number of antennas 310 may be used to produce a single beam 315. In some examples, beam 315 may be an example of a spatial stream. For example, antennas 310 at the network entity may produce or generate separately decoded data signals, which may be referred to as spatial streams. Accordingly, network entity 105-a may communicate with UEs 115-b and 115-c via one or more sets of beams 315 via communication links 320-a and 320-b, respectively.

[0111] In some examples, network entity 105-a may use different sets of beams 315 to communicate with different devices. For example, network entity 105-a may use a first set of beams 315 including beams 315-a, 315-b, and 315-c to communicate with UE 115-b via communication link 320-a, and network entity 105-a may use a second set of beams 315 including beams 315-d and 315-e to communicate with UE 115-c via communication link 320-b. To perform communication with network entity 105-a, UEs 115-a and 115-b may know or be aware of the number of beams 315 used for communication. For example, UE 115-b may receive a message (e.g., RRC configuration or some other control message) indicating how many beams 315 (e.g., spatial streams) will be used to receive downlink transmission 325-a (e.g., three in the example of Figure 3 ). UE 115 may receive and measure downlink transmission 325 based on the number of beams 315 to determine CSI parameter 340 for CSI report 335. However, in some cases, UE 115 may not know the number of antennas 310 that network entity 105-a uses for communication.

[0112] The techniques, systems, and devices described herein enable network entity 105-a to indicate to UE 115 the number of antennas 310 that are activated at network entity 105-a for downlink transmission 325 to UE 115. UE 115 may use the indicated number of antennas 310 to improve the estimation or calculation of CSI parameter 340, improve demodulation at UE 115, or both. Network entity 105-a may indicate the number of antennas 310 via control signaling 330 (e.g., control signaling 330-a or control signaling 330-b). The control signaling may include, for example, one or more DCI messages, one or more RRC messages, other types of control messages, or any combination thereof. Control signaling 330 may include one or more bits in a field configured to indicate the number of antennas 310.

[0113] The number of antennas 310 indicated to a given UE 115 via control signaling 330 may indicate the transmit antennas 310 that are activated for downlink transmission 325 to that respective UE 115. The network entity 105-a may use different sets of antennas 310 to communicate with different devices. For example, the network entity 105-a may utilize a first set of one or more antennas 310 of the antenna panel 305 and corresponding beams 315 to send a downlink transmission 325-a to UE 115-b (e.g., and one or more other UEs 115 included in the same UE group or sector), and the network entity 105-a may utilize a second set of one or more antennas 310 of the antenna panel 305 and corresponding beams 315 to send a downlink transmission 325-b to UE 115-c (e.g., and one or more other UEs 115 included in the same UE group or sector). Thus, the control signaling 330-a sent to UE 115-b may indicate the number of activated antennas 310 from the first set, and the control signaling 330-b sent to UE 115-c may indicate the number of activated antennas 310 from the second set.

[0114] In some examples, the network entity 105-a may periodically send control signaling 330 during communication with the UE 115. For example, after establishing a connection with UE 115-b, the network entity 105-a may send two or more DCI messages to UE 115-b according to the configured periodicity to indicate the number of antennas 310 that are activated at the network entity 105-a. The number of antennas 310 may be the same over time or may change dynamically such that each periodic message may indicate the same or a different number. Additionally or alternatively, the network entity 105-a may dynamically send control signaling 330 in response to a trigger. The trigger may be, for example, a change in the number of antennas 310 that are activated at the network entity 105-a, or some other trigger (e.g., a change in communication parameters, etc.). In such cases, each control message sent by the network entity 105-a may indicate an updated (e.g., different, new) number of activated antennas 310. The network entity 105-a may thus send control signaling 330 periodically, aperiodically, or semi-statically.

[0115] The UE 115 (e.g., UE 115-b or UE 115-c) as described herein may receive control signaling 330 and use the indicated number of antennas 310 to determine communication parameters, which may improve accuracy, coordination between devices, communication reliability, etc. For example, UE 115-b may determine (e.g., generate, select, adapt) CSI parameters 340 based on the number of antennas 310 indicated via control signaling 330-a. The CSI parameters 340 may include a CSI rank for communication (e.g., the number of spatial streams or beams 315), a PMI for communication, an MCS for communication, one or more other CSI parameters 340, or any combination thereof.

[0116] The value of each of the CSI parameters may be related to the number of antennas 310 at network entity 105-a. Thus, if UE 115-b knows the number of antennas 310 of the antenna panel 305 to be used for downlink transmission 325-a, UE 115-b may more accurately select or calculate the rank, PMI, or MCS for communicating with network entity 105-a. For example, the MCS complexity may be negatively correlated with the number of antennas 310. For example, if the number of antennas 310 is relatively large, UE 115-b may select a less complex MCS, or alternatively, if the number of antennas 310 is relatively small, UE 115-b may select a more complex MCS. A more complex MCS may improve communication reliability but may increase power consumption. Thus, by balancing the complexity of the MCS with the number of transmit antennas 310 at network entity 105-a, UE 115-b may determine an appropriate tradeoff between power consumption and communication reliability. As the number of transmit antennas 310 used at network entity 105-a increases, the rank and PMI that UE 115-b can support while still reliably decoding the downlink transmission 325 may increase proportionally. Thus, UE 115-b may select more aggressive or less aggressive CSI parameters 340 based on the indicated number of transmit antennas 310, which may improve efficiency while maintaining reliable communication.

[0117] In some examples, the UE 115-b may use that number of antennas 310 to reduce the demodulation complexity associated with demodulating and decoding the downlink transmission 325-a. The UE 115-b may include one or more demodulators 345, including at least a first demodulator 345-a and a second demodulator 345-b. The UE 115-b may use at least one of the demodulators 345 to demodulate each downlink transmission 325 received by the UE 115-b. Each of the demodulators 345 may be associated with a corresponding demodulation complexity. For example, the demodulator 345-a may correspond to a first complexity, and the demodulator 345-b may correspond to a second complexity. In some examples, the second complexity may be associated with a relatively lower complexity than the first complexity. As the demodulator complexity increases, the accuracy or reliability of demodulation may increase, and the power consumption may also increase.

[0118] The UE 115-b may compare the number of antennas 310 at the network entity 105-a with the rank of the downlink transmission 325 to determine which demodulator 345 to use to demodulate the downlink transmission 325. In some examples, the number of antennas 310 being used at the network entity 105-a may be greater than the rank of the downlink transmission 325 (e.g., ). The rank of the downlink transmission 325 may correspond to the number of spatial streams being used for the downlink transmission 325, which may indicate that the beam 315 generated by the network entity 105-a may be relatively more precise. This relationship between a relatively low rank and a relatively high number of transmit antennas 310 may be associated with a relatively low spatial correlation between the spatial streams and a relatively low inter-stream interference (ISI). Thus, this correlation may cause the UE 115-b to select a relatively low-complexity demodulator 345 (e.g., a demodulator 345 that cannot mitigate ISI, such as a demodulator 345 using the minimum mean square error (MMSE) model) to reduce power consumption while maintaining demodulation accuracy and reliability.

[0119] In some specific implementations, UE 115-b may detect that the number of antennas 310 activated at network entity 105-a for downlink transmission 325-a is at least a threshold number or threshold ratio greater than the number of spatial streams (e.g., beam 315) associated with downlink transmission 325-a. This threshold may be configured at UE 115-b or indicated to UE 115-b via a control message. In such cases, UE 115-b may select a demodulator 345 with relatively low demodulation complexity. In one example, the threshold ratio may be equal to 2:1, and the ratio of antennas 310 to beam 315 for downlink transmission 325-a may be 3:1. The ratio of the number of antennas 310 of UE 115-b to the number of beam 315 may be greater than the threshold ratio value (e.g., 3:1 > 2:1), which may trigger UE 115-b to select a less complex demodulator 345. For example, UE 115-b may switch from a first demodulator 345-a associated with a first complexity to a second demodulator 345-b associated with a second complexity based on the second complexity being less complex than the first complexity. In some cases, when initiating communication between network entity 105-a and UE 115-b, the threshold ratio or number for selecting demodulator 345 may be pre-configured, or the threshold may be sent from network entity 105-a to UE 115-b in control signaling 330.

[0120] In one example, 20 antennas 310 (e.g., or some other number of antennas 310) may be activated at network entity 105-a, and three spatial streams may be used for downlink transmission 325-a. UE 115-b may detect this relationship between the rank and antennas 310, and UE 115-b may switch from using demodulator 345-a to using demodulator 345-b, which may be associated with a relatively lower complexity than demodulator 345-a. UE 115-b may thus reduce power consumption, processing complexity, and latency while maintaining communication and demodulation reliability and accuracy.

[0121] In some cases, the performance and accuracy of measurements used to determine the value of CSI parameter 340 can be increased based on the number of antennas 310 indicated by network entity 105-a that are active at network entity 105-a for communication with UE 115-b. For example, if network entity 105-a indicates the number of transmit antennas 310 to UE 115-b, but network entity 105-a does not indicate the number of transmit antennas 310 to UE 115-c, then the CSI report 335 generated by UE 115-b can be more accurate than the CSI report generated by UE 115-c because UE 115-b can use the knowledge of the number of transmit antennas 310 when generating CSI report 335. The number of antennas 310 and the corresponding number of beams 315 generated by network entity 105-a can affect channel parameters, including CSI parameter 340. For example, beams 315 can be associated with different directions and coverage areas from network entity 105-a. Thus, an increase in the number of antennas 310 and beams 315 can increase throughput because network entity 105-a can support an increased number of directions for communication with UE 115-b. Even if the location, rate, and speed of UE 115-b change dynamically, an increase in the number of antennas 310, the number of beams 315, or both can improve communication reliability. For example, if network entity 105-a supports a relatively large coverage area in various different directions due to an increase in the number of antennas 310 and beams 315, then UE 115-b may be able to receive messages and synchronize from network entity 105-a, which can include control signaling 330-a, while changing its location and rate more reliably compared to a situation where the number of antennas 310, the number of beams 315, or both are reduced. Therefore, UE 115-b can select the CSI parameter based on the number of antennas 310 at network entity 105-a, which can improve the accuracy of the CSI report.

[0122] The UE 115 described herein can thus receive control signaling 330 indicating the number of transmit antennas 310 activated at network entity 105-a, and the UE 115 can use the value of the number of the indicated antennas 310 to support reduced power consumption and increased power savings at the UE 115 while maintaining or increasing spectral efficiency. Spectral efficiency can relate to the amount of data transmitted in a given spectrum or frequency bandwidth. Thus, if the UE 115-b determines that there may be a relatively large number of antennas 310 available at network entity 105-a for transmission compared to the number of spatial streams being used for downlink transmission 325-a (e.g., greater than a threshold number or threshold ratio), the UE 115-b can determine that a lower complexity demodulator 345 can be used due to the number of antennas 310 being used for downlink transmission 325-a to maintain spectral efficiency while maintaining throughput and demodulation reliability. Accordingly, the UE 115-b can switch from a higher complexity demodulator (e.g., first demodulator 345-a) to a lower complexity demodulator (e.g., second demodulator 345-b), which can reduce the power consumption of the UE 115-b without reducing spectral efficiency.

[0123] Accordingly, the techniques described herein can support network entity 105-a in sending control signaling 330 to the UE 115 to indicate the number of antennas 310 of antenna panel 305 that are activated for downlink transmission 325. Such control signaling 330 can support reduced power consumption and increased power savings effects while maintaining the spectral efficiency of the communication for the communication.

[0124] Figure 4 An example of a process flow 400 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure is illustrated. In some examples, the process flow 400 can implement aspects of the wireless communication system 100 or 300 or network architecture 200, or can be implemented by aspects of the wireless communication system or the network architecture, as described with reference to Figures 1 to 3 For example, the process flow 400 can include a UE 115-d and a network entity 105-b, which can be examples of the UE 115 and network entity 105 as described with reference to Figures 1 to 3 In this example, the network entity 105-b can indicate to the UE 115-d the number of transmit antennas activated at the network entity 105-b, which can improve communication reliability and coordination between devices.

[0125] In the following description of process flow 400, the operations between UE 115-d and network entity 105-b may be performed in a different order or at different times. Some operations may also be excluded from process flow 400, or additional operations may be added. Although UE 115-d and network entity 105-b are shown as performing the operations of process flow 400, some aspects of some operations may also be performed by one or more other wireless devices.

[0126] At 405, UE 115-d may receive control signaling from network entity 105-b indicating the number of transmit antennas at network entity 105-b. The number of transmit antennas may include the antennas that can be activated for downlink transmission to UE 115-d. In some examples, UE 115-d may receive multiple control messages as part of the control signaling received at 405. The first control message may indicate the number of transmit antennas that can be activated at network entity 105-b at a first time, and one or more of the other control messages may indicate one or more other numbers of transmit antennas that can be activated at network entity 105-b at one or more other times different from the first time. For example, network entity 105-b may send control messages periodically or aperiodically (e.g., based on a trigger such as a change in the number of transmit antennas), and each control message may indicate the corresponding number of transmit antennas that can be activated at network entity 105-b during the corresponding time period associated with the periodicity or timing of the control message. The control message may include a DCI message, an RRC configuration, some other type of control message, or any combination thereof.

[0127] At 410, in some examples, UE 115-d may switch from a first demodulator of UE 115-d to a second demodulator of UE 115-d based on the number of transmit antennas indicated via the control signaling. In some examples, UE 115-d may identify the number of spatial streams associated with the downlink transmission. As Figure 3 described, a spatial stream may correspond to or represent an example of a beam or stream of energy or signaling generated by the antennas of an antenna panel at network entity 105-b. Thus, the number of spatial streams may be associated with the number of transmit antennas activated at network entity 105-b for communication with UE 115-d. These beams may be further described elsewhere herein, including with reference to Figure 3 . UE 115-d may include multiple demodulators, as Figure 3 described. UE 115-d may select a second demodulator from the multiple demodulators of UE 115-d for demodulation of the downlink transmission based on the relationship between the number of transmit antennas and the number of spatial streams associated with the downlink transmission.

[0128] In some examples, each of the multiple demodulators of UE 115-d may be associated with a corresponding demodulation complexity. UE 115-d may determine that the number of indicated transmit antennas may be at least a threshold number or a threshold ratio greater than the number of spatial streams associated with the downlink transmission. In such cases, UE 115-d may select a second demodulator associated with a second complexity based on determining that the number of indicated transmit antennas is at least that threshold greater than the number of spatial streams, where the second complexity is relatively lower than a first complexity associated with a first demodulator and one or more other complexities associated with one or more of the other demodulators of that number of demodulators. UE 115-d may switch from the first demodulator to the second demodulator based on selecting the second demodulator.

[0129] At 415, UE 115-d may send a CSI report including a set of one or more CSI parameters to network entity 105-b. The set of one or more CSI parameters may be based on the number of transmit antennas at network entity 105-b indicated via control signaling. The set of one or more CSI parameters may include a PMI, a rank, an MCS, one or more other CSI parameters, or any combination thereof for receiving the downlink transmission. In some cases, UE 115-d may determine the set of one or more CSI parameters based on the number of transmit antennas indicated at network entity 105-b and one or more conditions at UE 115-d, such as the location of UE 115-d, the speed or rate of UE 115-d, one or more other conditions of UE 115-d, or any combination thereof. In some examples, the value of each CSI parameter in the set of one or more CSI parameters may be related to the number of transmit antennas at network entity 105-b.

[0130] At 420, UE 115-d may communicate with network entity 105-b based on the set of one or more CSI parameters indicated via the CSI report. For example, UE 115-d may receive the downlink transmission, send the uplink transmission, or both according to the CSI parameters and demodulator selected by UE 115-d.

[0131] In some examples, UE 115-d may detect a change in one or more parameters associated with the communication between UE 115-d and network entity 105-b. In such cases, if the communication parameter changes by more than a threshold amount (e.g., or within a threshold time period), then UE 115-d may send a second CSI report in response to detecting the change to indicate a second set of one or more CSI parameters. For example, UE 115-d may apply a backoff. In some examples, the difference between the set of one or more CSI parameters indicated via the first CSI report and the second set of one or more CSI parameters (e.g., the amount of backoff applied by UE 115-d) may be based on the number of indicated antennas at the network entity and the change in the one or more communication parameters. That is, if the number of transmit antennas activated at network entity 105-b is relatively high, then UE 115-d may reduce the amount of backoff applied by UE 115-d, or if the number of transmit antennas activated at network entity 105-b is relatively low, then the amount of backoff applied by UE 115-d may be increased. Network entity 105-b may send a second downlink transmission based on the second set of one or more CSI parameters indicated via the second CSI report.

[0132] The network entity 105-b and UE 115-d described herein may thus reduce power consumption, increase power savings, and improve CSI reporting accuracy by exchanging information indicating the number of transmit antennas for downlink transmission. This information may support UE 115-d in more accurately selecting and calculating a set of one or more CSI parameters and may support network entity 105-b in increasing the accuracy of communication between network entity 105-b and UE 115-d.

[0133] Figure 5 Block diagram 500 illustrates a device 505 supporting reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. Device 505 may be an example of aspects of UE 115 as described herein. Device 505 may include a receiver 510, a transmitter 515, and a communication manager 520. Device 505 may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0134] Receiver 510 may provide components 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 reporting the number of transmit antennas for wireless communication). The information may be passed to other components of device 505. Receiver 510 may utilize a single antenna or a collection of multiple antennas.

[0135] Transmitter 515 may provide a component for transmitting signals generated by other components of device 505. For example, transmitter 515 may 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 reporting the number of transmit antennas for wireless communication). In some examples, transmitter 515 may be co-located with receiver 510 in a transceiver module. Transmitter 515 may utilize a single antenna or a collection of multiple antennas.

[0136] Communication manager 520, receiver 510, transmitter 515, or various combinations thereof, or various components thereof, may be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, communication manager 520, receiver 510, transmitter 515, or various combinations or components thereof may support methods for performing one or more of the functions described herein.

[0137] In some examples, communication manager 520, receiver 510, transmitter 515, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a digital signal processor (DSP), a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports components for performing the functions described in this disclosure. In some examples, a processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0138] Additionally or alternatively, in some examples, communication manager 520, receiver 510, transmitter 515, or various combinations or components thereof may be implemented in code executed by a processor (e.g., implemented as communication management software or firmware). If implemented in code executed by a processor, the functions of communication manager 520, receiver 510, transmitter 515, or various combinations or components thereof may be performed by a general purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices that is configured to or otherwise supports components for performing the functions described in this disclosure.

[0139] In some examples, the communication manager 520 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in cooperation with the receiver 510, the transmitter 515, or both. For example, the communication manager 520 may receive information from the receiver 510, convey information to the transmitter 515, or be integrated in combination with the receiver 510, the transmitter 515, or both to obtain information, output information, or perform various other operations as described herein.

[0140] Additionally or alternatively, according to examples as disclosed herein, the communication manager 520 may support wireless communication at a UE. For example, the communication manager 520 may be configured to or otherwise support components for receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas that are activated for downlink transmission to the UE. The communication manager 520 may be configured to or otherwise support components for transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication manager 520 may be configured to or otherwise support components for communicating with a network entity based on a set of one or more CSI parameters indicated via the CSI report.

[0141] By including or configuring the communication manager 520 according to examples as described herein, the device 505 (e.g., a processor that controls or otherwise is coupled with the receiver 510, the transmitter 515, the communication manager 520, or a combination thereof) may support techniques for reducing power consumption and increasing power savings.

[0142] Figure 6 Block diagram 600 illustrates a device 605 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The device 605 may be an example of aspects of the device 505 or UE 115 as described herein. The device 605 may include a receiver 610, a transmitter 615, and a communication manager 620. The device 605 may also include a processor. Each of these components may communicate with one another (e.g., via one or more buses).

[0143] The receiver 610 may provide components 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 related to reporting the number of transmit antennas for wireless communication). The information may be passed to other components of the device 605. The receiver 610 may utilize a single antenna or a collection of multiple antennas.

[0144] The transmitter 615 can provide components 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 reporting the number of transmit antennas for wireless communication). 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 a set of multiple antennas.

[0145] The device 605 or its various components can be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, the communication manager 620 can include a control signaling component 625, a CSI reporting component 630, a communication component 635, or any combination thereof. The communication manager 620 can be an example of aspects of the communication manager 520 as described herein. In some examples, the communication manager 620 or its various components can be configured to use or otherwise cooperate with the receiver 610, the transmitter 615, or both to perform various operations (e.g., receive, obtain, monitor, output, transmit). For example, the communication manager 620 can receive information from the receiver 610, convey information to the transmitter 615, or integrate with the receiver 610, the transmitter 615, or both to obtain information, output information, or perform various other operations as described herein.

[0146] According to examples disclosed herein, the communication manager 620 can support wireless communication at the UE. The control signaling component 625 can be configured to or otherwise support components for receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE. The CSI reporting component 630 can be configured to or otherwise support components for transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication component 635 can be configured to or otherwise support components for communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0147] Figure 7FIG. 700 is a block diagram illustrating a communication manager 720 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The communication manager 720 may be an example of the communication manager 520, the communication manager 620, or aspects of both as described herein. The communication manager 720 or its various components may be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, the communication manager 720 may include a control signaling component 725, a CSI reporting component 730, a communication component 735, a demodulator switching component 740, a channel parameter component 745, a CSI parameter component 750, a spatial stream identifier 755, a downlink transmission component 760, a demodulation component 765, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0148] Additionally or alternatively, in accordance with examples as disclosed herein, the communication manager 720 may support wireless communication at a UE. The control signaling component 725 may be configured to or otherwise support a component for receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas that are active for downlink transmission to the UE. The CSI reporting component 730 may be configured to or otherwise support a component for transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication component 735 may be configured to or otherwise support a component for communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0149] In some examples, to support receiving control signaling, the control signaling component 725 may be configured to or otherwise support a component for receiving a set of multiple control messages, where a first control message in the set of multiple control messages indicates the number of transmit antennas that are active at the network entity at a first time, and where one or more other control messages in the set of multiple control messages indicate one or more other numbers of transmit antennas that are active at the network entity at one or more other times different from the first time.

[0150] In some examples, to support receiving the set of multiple control messages, the control signaling component 725 may be configured to or otherwise support a component for periodically receiving the set of multiple control messages, where each of the set of multiple control messages indicates the corresponding number of transmit antennas that are active at the network entity during a corresponding time period associated with the periodicity of the set of multiple control messages.

[0151] In some examples, to support receiving the set of multiple control messages, the control signaling component 725 may be configured to or otherwise support components for receiving the set of multiple control messages either non-periodically or periodically, where one or more of the set of multiple control messages indicate corresponding changes in the number of transmit antennas activated at a network entity.

[0152] In some examples, to support receiving control signaling, the control signaling component 725 may be configured to or otherwise support components for receiving DCI indicating the number of transmit antennas.

[0153] In some examples, to support receiving control signaling, the control signaling component 725 may be configured to or otherwise support components for receiving RRC signaling indicating the number of transmit antennas.

[0154] In some examples, the demodulator switching component 740 may be configured to or otherwise support components for switching from a first demodulator in a set of multiple demodulators of a UE to a second demodulator in the set of multiple demodulators based on the indicated number of transmit antennas.

[0155] In some examples, the spatial stream identifier 755 may be configured to or otherwise support components for identifying the number of spatial streams associated with a downlink transmission. In some examples, the demodulator switching component 740 may be configured to or otherwise support components for selecting a second demodulator from a set of multiple demodulators of a UE for demodulating a downlink transmission based on a relationship between the indicated number of transmit antennas and the number of spatial streams associated with the downlink transmission, where switching from the first demodulator to the second demodulator is based on the selection of the second demodulator. In some examples, the downlink transmission component 760 may be configured to or otherwise support components for receiving a downlink transmission. In some examples, the demodulation component 765 may be configured to or otherwise support components for demodulating the downlink transmission using the selected demodulator.

[0156] In some examples, each demodulator in the set of multiple demodulators of the UE is associated with a corresponding demodulation complexity, and the spatial stream identifier 755 can be configured to or otherwise support components for determining that the number of indicated transmit antennas is at least a threshold number or threshold ratio greater than the number of spatial streams associated with the downlink transmission. In some examples, each demodulator in the set of multiple demodulators of the UE is associated with a corresponding demodulation complexity, and the demodulator switching component 740 can be configured to or otherwise support components for selecting a second demodulator associated with a second complexity based on this determination, where the second complexity is less than the first complexity associated with the first demodulator and one or more other complexities associated with one or more other demodulators in the set of multiple demodulators, and switching from the first demodulator to the second demodulator is based on the selection of the second demodulator.

[0157] In some examples, the channel parameter component 745 can be configured to or otherwise support components for detecting a change in one or more channel parameters associated with the communication between the UE and the network entity. In some examples, the CSI reporting component 730 can be configured to or otherwise support components for sending a second CSI report in response to detecting the change to indicate a second set of one or more CSI parameters, where the difference between the set of one or more CSI parameters and the second set of one or more CSI parameters is based on the number of indicated antennas at the network entity and the change in the one or more channel parameters.

[0158] In some examples, the CSI parameter component 750 can be configured to or otherwise support components for determining the set of one or more CSI parameters based on conditions at the UE and the number of indicated transmit antennas at the network entity, where the value of each CSI parameter in the set of one or more CSI parameters is related to the number of transmit antennas at the network entity.

[0159] In some examples, the set of one or more CSI parameters includes a PMI, rank, MCS, or any combination thereof for receiving the downlink transmission.

[0160] Figure 8FIG. 800 illustrates a system 800 including a device 805 that supports reporting the number of transmit antennas for wireless communication. The device 805 may be an example of the device 505, the device 605, or the UE 115 as described herein, or include components thereof. The device 805 may communicate (e.g., wirelessly) with one or more network entities 105, one or more UEs 115, or any combination thereof. The device 805 may include components for two-way voice and data communication, including components for transmitting and receiving communications, such as a communication manager 820, an input / output (I / O) controller 810, a transceiver 815, an antenna 825, a memory 830, code 835, and a processor 840. These components may communicate electronically via one or more buses (e.g., bus 845) or otherwise be coupled (e.g., operatively, communicatively, functionally, electronically, electrically).

[0161] The I / O controller 810 may manage input and output signals of the device 805. The I / O controller 810 may also manage peripheral devices not integrated into the device 805. In some cases, the I / O controller 810 may represent a physical connection or port to an external peripheral device. In some cases, the I / O controller 810 may utilize an operating system, such as iOS ® , ANDROID ® , MS-DOS ® , MS-WINDOWS ® , OS / 2 ® , UNIX ® , LINUX ® or another known operating system. Additionally or alternatively, the I / O controller 810 may represent, or interact with, a modem, a keyboard, a mouse, a touch screen, or similar device. In some cases, the I / O controller 810 may be implemented as part of a processor (such as the processor 840). In some cases, a user may interact with the device 805 via the I / O controller 810 or via hardware components controlled by the I / O controller 810.

[0162] In some cases, device 805 may include a single antenna 825. However, in some other cases, device 805 may have more than one antenna 825, and the more than one antenna may be capable of concurrently transmitting or receiving multiple wireless transmissions. Transceiver 815 may communicate bidirectionally via one or more antennas 825, wired or wireless links as described herein. For example, transceiver 815 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. Transceiver 815 may also include a modem for: modulating packets; providing the modulated packets to one or more antennas 825 for transmission; and demodulating packets received from one or more antennas 825. Transceiver 815 or transceiver 815 and one or more antennas 825 may be examples of transmitter 515, transmitter 615, receiver 510, receiver 610, or any combination thereof or their components as described herein.

[0163] Memory 830 may include random access memory (RAM) and read-only memory (ROM). Memory 830 may store computer-readable, computer-executable code 835 including instructions that, when executed by processor 840, cause device 805 to perform the various functions described herein. Code 835 may be stored in a non-transitory computer-readable medium (such as system memory or another type of memory). In some cases, code 835 may not be directly executable by processor 840 but may, for example, cause a computer to perform the functions described herein when compiled and executed. In some cases, memory 830 may particularly include a basic input / output system (BIOS) that may control basic hardware or software operations, such as interactions with peripheral components or devices.

[0164] Processor 840 may include intelligent hardware devices (e.g., 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 840 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into processor 840. Processor 840 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 830) to cause device 805 to perform various functions (e.g., support a function or task of reporting the number of transmit antennas for wireless communication). For example, device 805 or components of device 805 may include processor 840 and memory 830 coupled or coupled to processor 840, and processor 840 and memory 830 are configured to perform the various functions described herein.

[0165] Additionally or alternatively, according to examples as disclosed herein, the communication manager 820 may support wireless communication at the UE. For example, the communication manager 820 may be configured to or otherwise support components for receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas that are activated for downlink transmission to the UE. The communication manager 820 may be configured to or otherwise support components for transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication manager 820 may be configured to or otherwise support components for communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report.

[0166] By including or configuring the communication manager 820 according to examples as described herein, the device 805 may support techniques for improved communication reliability, reduced latency, improved user experience associated with reduced processing, reduced power consumption, improved coordination between devices, and longer battery life. For example, by receiving an indication of the number of transmit antennas activated at a network entity, the device 805 (e.g., UE) may improve the accuracy of CSI parameter selection, which may improve throughput and communication reliability. Additionally or alternatively, the device 805 may use the indicated number of transmit antennas to select and switch from a first demodulator to a second demodulator that may be associated with a relatively lower or higher complexity than the complexity of the first demodulator. By using fewer computational resources of the device 805 to maintain reliable and accurate communication, the selection of demodulation complexity based on the number of transmit antennas may support reduced power consumption, reduced processing, and longer battery life of the device 805.

[0167] In some examples, the communication manager 820 may be configured to use or otherwise cooperate with the transceiver 815, one or more antennas 825, or any combination thereof to perform various operations (e.g., receive, monitor, transmit). Although the communication manager 820 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 820 may be supported or performed by the processor 840, the memory 830, the code 835, or any combination thereof. For example, the code 835 may include instructions that can be executed by the processor 840 to cause the device 805 to perform various aspects of reporting the number of transmit antennas for wireless communication as described herein, or the processor 840 and the memory 830 may be otherwise configured to execute or support such operations.

[0168] Figure 9FIG. 900 is a block diagram of an apparatus 905 that illustrates an apparatus supporting reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. Apparatus 905 may be an example of aspects of network entity 105 as described herein. Apparatus 905 may include a receiver 910, a transmitter 915, and a communication manager 920. Apparatus 905 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0169] The receiver 910 may provide components for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of apparatus 905. In some examples, the receiver 910 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 910 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof.

[0170] The transmitter 915 may provide components for outputting (e.g., transmitting, providing, conveying, delivering) information generated by other components of apparatus 905. For example, the transmitter 915 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 915 may support outputting information by transmitting signals via one or more antennas. Additionally or alternatively, the transmitter 915 may support outputting information by transmitting signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 915 and the receiver 910 may be co-located in a transceiver that may include a modem or be coupled to a modem.

[0171] The communication manager 920, the receiver 910, the transmitter 915, or various combinations thereof, or various components thereof, may be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may support methods for performing one or more of the functions described herein.

[0172] In some examples, the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA, or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports components for performing the functions described in this disclosure. In some examples, the processor and the memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

[0173] Additionally or alternatively, in some examples, the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be implemented in code executed by a processor (e.g., implemented as communication management software or firmware). If implemented in code executed by a processor, the functions of the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices that is configured to or otherwise supports components for performing the functions described in this disclosure.

[0174] In some examples, the communication manager 920 may be configured to use or otherwise cooperate with the receiver 910, the transmitter 915, or both to perform various operations (e.g., receive, obtain, monitor, output, transmit). For example, the communication manager 920 may receive information from the receiver 910, convey information to the transmitter 915, or integrate in combination with the receiver 910, the transmitter 915, or both to obtain information, output information, or perform various other operations as described herein.

[0175] Additionally or alternatively, according to examples disclosed herein, the communication manager 920 may support wireless communication at a network entity. For example, the communication manager 920 may be configured to or otherwise support components for transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE. The communication manager 920 may be configured to or otherwise support components for receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication manager 920 may be configured to or otherwise support components for communicating with a UE based on the set of one or more CSI parameters indicated via the CSI report.

[0176] By including or configuring a communication manager 920 according to an example as described herein, a device 905 (e.g., a processor that controls or otherwise is coupled to a receiver 910, a transmitter 915, a communication manager 920, or a combination thereof) can support techniques for reduced power consumption, reduced processing, and increased power savings.

[0177] Figure 10 FIG. 1000 is a block diagram illustrating a device 1005 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The device 1005 may be an example of aspects of the device 905 or the network entity 105 as described herein. The device 1005 may include a receiver 1010, a transmitter 1015, and a communication manager 1020. The device 1005 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0178] The receiver 1010 may provide components for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of the device 1005. In some examples, the receiver 1010 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 1010 may support obtaining information by receiving signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof.

[0179] The transmitter 1015 may provide components for outputting (e.g., transmitting, providing, conveying, delivering) information generated by other components of the device 1005. For example, the transmitter 1015 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 1015 may support outputting information by transmitting signals via one or more antennas. Additionally or alternatively, the transmitter 1015 may support outputting information by transmitting signals via one or more wired (e.g., electrical, fiber optic) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 1015 and the receiver 1010 may be co-located in a transceiver that may include a modem or be coupled to a modem.

[0180] Device 1005 or its various components can be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, communication manager 1020 can include control signaling component 1025, CSI reporting component 1030, communication component 1035, or any combination thereof. Communication manager 1020 can be an example of aspects of communication manager 920 as described herein. In some examples, communication manager 1020 or its various components can be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in cooperation with receiver 1010, transmitter 1015, or both. For example, communication manager 1020 can receive information from receiver 1010, convey information to transmitter 1015, or integrate with receiver 1010, transmitter 1015, or both to obtain information, output information, or perform various other operations as described herein.

[0181] According to examples disclosed herein, communication manager 1020 can support wireless communication at a network entity. Control signaling component 1025 can be configured to or otherwise support components for transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE. CSI reporting component 1030 can be configured to or otherwise support components for receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. Communication component 1035 can be configured to or otherwise support components for communicating with a UE based on a set of one or more CSI parameters indicated via the CSI report.

[0182] Figure 11FIG. 1100 is a block diagram illustrating a communication manager 1120 that supports reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The communication manager 1120 may be an example of the communication manager 920, the communication manager 1020, or aspects of both as described herein. The communication manager 1120 or its various components may be examples of components for performing various aspects of reporting the number of transmit antennas for wireless communication as described herein. For example, the communication manager 1120 may include a control signaling component 1125, a CSI reporting component 1130, a communication component 1135, a downlink transmission component 1140, a transmit antenna component 1145, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses), and such communication may include communication within protocol layers of a protocol stack, communication associated with logical channels of the protocol stack (e.g., between protocol layers of the protocol stack, within a device, component, or virtualized component associated with the network entity 105, between devices, components, or virtualized components associated with the network entity 105), or any combination thereof.

[0183] Additionally or alternatively, in accordance with examples as disclosed herein, the communication manager 1120 may support wireless communication at a network entity. The control signaling component 1125 may be configured to or otherwise support a component for transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas that are activated for downlink transmission to a UE. The CSI reporting component 1130 may be configured to or otherwise support a component for receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The communication component 1135 may be configured to or otherwise support a component for communicating with the UE based on the set of one or more CSI parameters indicated via the CSI report.

[0184] In some examples, to support transmitting control signaling, the control signaling component 1125 may be configured to or otherwise support a component for transmitting a set of multiple control messages, where a first control message in the set of multiple control messages indicates the number of transmit antennas activated at the network entity at a first time, and where one or more other control messages in the set of multiple control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

[0185] In some examples, to support sending the set of multiple control messages, the control signaling component 1125 may be configured to or otherwise support components for periodically sending the set of multiple control messages, where each of the set of multiple control messages indicates a respective number of transmit antennas activated at a network entity during a respective time period associated with the periodicity of the set of multiple control messages.

[0186] In some examples, to support sending the set of multiple control messages, the transmit antenna component 1145 may be configured to or otherwise support components for determining a change in the number of transmit antennas activated at a network entity. In some examples, to support sending the set of multiple control messages, the control signaling component 1125 may be configured to or otherwise support components for sending control messages in the set of multiple control messages to indicate a change in the number of transmit antennas, where the set of multiple control messages is sent non-periodically or periodically, and where one or more of the set of multiple control messages indicate respective changes in the number of transmit antennas at the network entity.

[0187] In some examples, to support sending control signaling, the control signaling component 1125 may be configured to or otherwise support components for sending DCI indicating the number of transmit antennas.

[0188] In some examples, to support sending control signaling, the control signaling component 1125 may be configured to or otherwise support components for sending RRC signaling indicating the number of transmit antennas.

[0189] In some examples, the CSI reporting component 1130 may be configured to or otherwise support components for receiving a second CSI report indicating a second set of one or more CSI parameters after receiving a CSI report, where the difference between the set of one or more CSI parameters indicated via the CSI report and the second set of one or more CSI parameters indicated via the second CSI report is based on a change in the number of antennas at the network entity and one or more channel parameters associated with communication between the network entity and the UE. In some examples, the downlink transmission component 1140 may be configured to or otherwise support components for sending a second downlink transmission based on the second set of one or more CSI parameters indicated via the second CSI report.

[0190] In some examples, the value of each CSI parameter in the set of one or more CSI parameters is related to the number of transmit antennas at the network entity. In some examples, the set of one or more CSI parameters includes a PMI, rank, MCS, or any combination thereof for sending a downlink transmission.

[0191] Figure 12 FIG. illustrates a system 1200 including a device 1205 that supports reporting the number of transmit antennas for wireless communication, in accordance with one or more aspects of the present disclosure. The device 1205 may be an example of the device 905, the device 1005, or the network entity 105 described herein, or may include components thereof. The device 1205 may communicate with one or more network entities 105, one or more UEs 115, or any combination thereof, and such communication may include communication via one or more wired interfaces, via one or more wireless interfaces, or any combination thereof. The device 1205 may include components that support outputting and obtaining communication, such as a communication manager 1220, a transceiver 1210, an antenna 1215, a memory 1225, code 1230, and a processor 1235. These components may communicate electronically via one or more buses (e.g., bus 1240) or may be otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically).

[0192] The transceiver 1210 may support bidirectional communication via a wired link, a wireless link, or both as described herein. In some examples, the transceiver 1210 may include a wired transceiver and may communicate bidirectionally with another wired transceiver. Additionally or alternatively, in some examples, the transceiver 1210 may include a wireless transceiver and may communicate bidirectionally with another wireless transceiver. In some examples, the device 1205 may include one or more antennas 1215, which may be capable of (e.g., concurrently) sending or receiving wireless transmissions. The transceiver 1210 may also include a modem for: modulating a signal; providing the modulated signal for transmission (e.g., via one or more antennas 1215, via a wired transmitter); receiving the modulated signal (e.g., from one or more antennas 1215, from a wired receiver); and demodulating the signal. In some implementations, the transceiver 1210 may include one or more interfaces, such as one or more interfaces coupled to one or more antennas 1215 configured to support various receiving or obtaining operations, or one or more interfaces coupled to one or more antennas 1215 configured to support various transmitting or outputting operations, or a combination thereof. In some implementations, the transceiver 1210 may include or be configured to be coupled to one or more processors or memory components, which may be operable to perform or support operations based on received or obtained information or signals, or to generate information or other signals for transmission or other output, or any combination of the above. In some implementations, the transceiver 1210, or the transceiver 1210 and one or more antennas 1215, or the transceiver 1210 and one or more antennas 1215 and one or more processors or memory components (e.g., processor 1235 or memory 1225 or both) may be included in a chip or chip assembly installed in the device 1205. In some examples, the transceiver may be operable to support communications via one or more communication links (eg, communication link 125 , backhaul communication link 120 , midhaul communication link 162 , fronthaul communication link 168 ).

[0193] The memory 1225 may include RAM and ROM. The memory 1225 may store computer-readable, computer-executable code 1230 including instructions that, when executed by the processor 1235, cause the device 1205 to perform the various functions described herein. The code 1230 may be stored in a non-transitory computer-readable medium (such as system memory or another type of memory). In some cases, the code 1230 may not be directly executable by the processor 1235 but may (e.g., when compiled and executed) cause the computer to perform the functions described herein. In some cases, the memory 1225 may particularly include the BIOS, which may control basic hardware or software operations, such as interactions with peripheral components or devices.

[0194] The processor 1235 may include intelligent hardware devices (e.g., general-purpose processors, DSPs, ASICs, CPUs, FPGAs, microcontrollers, programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof). In some cases, the processor 1235 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1235. The processor 1235 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1225) to cause the device 1205 to perform various functions (e.g., support a function or task of reporting the number of transmit antennas for wireless communication). For example, the device 1205 or components of the device 1205 may include the processor 1235 and the memory 1225 coupled to the processor 1235, and the processor 1235 and the memory 1225 are configured to perform the various functions described herein. The processor 1235 may be an example of a cloud computing platform (e.g., one or more physical nodes and supporting software such as an operating system, virtual machine, or container instance), which may host functions (e.g., by executing code 1230) to perform the functions of the device 1205. The processor 1235 may be any one or more suitable processors capable of executing scripts or instructions of one or more software programs stored in the device 1205 (such as within the memory 1225). In some specific implementations, the processor 1235 may be a component of a processing system. A processing system generally may refer to a system or a series of machines or components that receive inputs and process these inputs to produce a set of outputs (which may be passed to other systems or components of, for example, the device 1205). For example, the processing system of the device 1205 may refer to a system including various other components or sub-components of the device 1205, such as the processor 1235, or the transceiver 1210, or the communication manager 1220, or a combination of other components or components of the device 1205. The processing system of the device 1205 may interface with other components of the device 1205 and may process information (such as inputs or signals) received from other components or output information to other components. For example, a chip or modem of the device 1205 may include a processing system and one or more interfaces for outputting information or for obtaining information or both. One or more interfaces may be implemented as or otherwise include a first interface configured to output information and a second interface configured to obtain information or the same interface configured to output information and obtain information, and other specific implementations. In some specific implementations, one or more interfaces may refer to an interface between the processing system of a chip or modem and a transmitter such that the device 1205 may transmit information output from the chip or modem.Additionally or alternatively, in some embodiments, one or more interfaces may refer to an interface between a processing system of a chip or modem and a receiver, such that device 1205 may obtain information or signal input, and the information may be passed to the processing system. One of ordinary skill in the art will readily recognize that the first interface may also obtain information or signal input, and the second interface may also output information or signal output.

[0195] In some examples, bus 1240 may support communication within a protocol layer of a protocol stack (e.g., within the protocol layer). In some examples, bus 1240 may support communication associated with a logical channel of a protocol stack (e.g., between protocol layers of the protocol stack), which may include communication performed within components of device 1205, or communication performed between different components of device 1205 that may be co-located or located at different locations (e.g., where device 1205 may refer to a system in which one or more of communication manager 1220, transceiver 1210, memory 1225, code 1230, and processor 1235 may be located in one component or divided among different components).

[0196] In some examples, communication manager 1220 may manage (e.g., via one or more wired or wireless backhaul links) aspects of communication with core network 130. For example, communication manager 1220 may manage the delivery of data communication for client devices (such as one or more UEs 115). In some examples, communication manager 1220 may manage communication with other network entities 105, and may include a controller or scheduler for coordinating with other network entities 105 to control communication with UE 115. In some examples, communication manager 1220 may support the X2 interface within LTE / LTE-A wireless communication network technology to provide communication between network entities 105.

[0197] Additionally or alternatively, according to examples disclosed herein, communication manager 1220 may support wireless communication at a network entity. For example, communication manager 1220 may be configured to or otherwise support components for transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE. Communication manager 1220 may be configured to or otherwise support components for receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. Communication manager 1220 may be configured to or otherwise support components for communicating with a UE based on a set of one or more CSI parameters indicated via the CSI report.

[0198] By including or configuring a communication manager 1220 according to examples as described herein, device 1205 may support techniques for improved communication reliability, reduced latency, improved user experience related to reduced processing, reduced power consumption, improved coordination between devices, and longer battery life. For example, by sending an indication of the number of transmit antennas activated at device 1205 (e.g., a network entity), device 1205 may improve coordination between device 1205 and one or more other devices (e.g., UEs) communicating with the device. Additionally or alternatively, the indicated number of transmit antennas may be used by other devices to improve CSI reporting accuracy and reduce complexity, which may reduce power consumption, reduce overhead, increase throughput, and increase the reliability of communication at device 1205.

[0199] In some examples, communication manager 1220 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise in conjunction with transceiver 1210, one or more antennas 1215 (e.g., where applicable), or any combination thereof. Although communication manager 1220 is illustrated as a separate component, in some examples, one or more of the functions described with reference to communication manager 1220 may be supported or performed by transceiver 1210, processor 1235, memory 1225, code 1230, or any combination thereof. For example, code 1230 may include instructions that can be executed by processor 1235 to cause device 1205 to perform various aspects of reporting the number of transmit antennas for wireless communication as described herein, or processor 1235 and memory 1225 may otherwise be configured to perform or support such operations.

[0200] Figure 13 A flowchart illustrating a method 1300 for supporting reporting the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure is shown. Operations of method 1300 may be implemented by a UE or components thereof as described herein. For example, operations of method 1300 may be performed by UE 115 as described with reference to Figures 1 to 8 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.

[0201] At 1305, the method may include receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE. The operation of 1305 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operation of 1305 may be performed by a control signaling component 725 as described with reference to Figure 7 In some examples, aspects of the operation of 1305 may be performed by a control signaling component 725 as described with reference to

[0202] At 1310, the method may include transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The operation of 1310 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1310 may be performed by a CSI reporting component 730 as described with reference to Figure 7 the CSI reporting component 730 described.

[0203] At 1315, the method may include communicating with the network entity based on the set of one or more CSI parameters indicated via the CSI report. The operation of 1315 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1315 may be performed by a communication component 735 as described with reference to Figure 7 the communication component 735 described.

[0204] Figure 14 FIG. shows a flow diagram of a method 1400 that illustrates supporting reporting of the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The operations of method 1400 may be implemented by a UE or components thereof as described herein. For example, the operations of method 1400 may be performed by a UE 115 as described with reference to Figures 1 to 8 the UE 115 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.

[0205] At 1405, the method may include receiving control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas that are activated for downlink transmission to the UE. The operation of 1405 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1405 may be performed by a control signaling component 725 as described with reference to Figure 7 the control signaling component 725 described.

[0206] At 1410, the method may include identifying the number of spatial streams associated with the downlink transmission. The operation of 1410 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1410 may be performed by a spatial stream identifier 755 as described with reference to Figure 7 the spatial stream identifier 755 described.

[0207] At 1415, the method may include selecting a second demodulator from the set of multiple demodulators of the UE for demodulating the downlink transmission based on a relationship between the indicated number of transmit antennas and the number of spatial streams associated with the downlink transmission. The operation of 1415 may be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1415 may be performed by a component as described with reference toFigure 7 performed by the described demodulator switching component 740.

[0208] At 1420, the method can include switching from a first demodulator in the set of multiple demodulators of the UE to a second demodulator based on selecting the second demodulator in the set of multiple demodulators. The operation of 1420 can be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1420 can be performed by a demodulator switching component 740 as described with reference to Figure 7 the described demodulator switching component 740.

[0209] At 1425, the method can include receiving a downlink transmission. The operation of 1425 can be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1425 can be performed by a downlink transmission component 760 as described with reference to Figure 7 the described downlink transmission component 760.

[0210] At 1430, the method can include demodulating the downlink transmission using the selected demodulator. The operation of 1430 can be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1430 can be performed by a demodulation component 765 as described with reference to Figure 7 the described demodulation component 765.

[0211] At 1435, the method can include transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The operation of 1435 can be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1435 can be performed by a CSI reporting component 730 as described with reference to Figure 7 the described CSI reporting component 730.

[0212] At 1440, the method can include communicating with the network entity based on a set of one or more CSI parameters indicated via the CSI report. The operation of 1440 can be performed according to the examples disclosed herein. In some examples, aspects of the operation of 1440 can be performed by a communication component 735 as described with reference to Figure 7 the described communication component 735.

[0213] Figure 15 A flowchart illustrating a method 1500 for supporting reporting of the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure is shown. The operations of method 1500 can be implemented by a network entity or its components as described herein. For example, the operations of method 1500 can be performed by a component as described with reference to Figures 1 to 4 and Figures 9 to 12performed by the described network entity. In some examples, the network entity may execute an instruction set to control functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform aspects of the described functions.

[0214] At 1505, the method may include sending control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE. The operation of 1505 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation of 1505 may be performed by the control signaling component 1125 as described with reference to Figure 11 the described control signaling component 1125.

[0215] At 1510, the method may include receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The operation of 1510 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation of 1510 may be performed by the CSI report component 1130 as described with reference to Figure 11 the described CSI report component 1130.

[0216] At 1515, the method may include communicating with the UE based on the set of one or more CSI parameters indicated via the CSI report. The operation of 1515 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation of 1515 may be performed by the communication component 1135 as described with reference to Figure 11 the described communication component 1135.

[0217] Figure 16 FIG. 1600 is a flow chart illustrating a method 1600 for supporting reporting of the number of transmit antennas for wireless communication in accordance with one or more aspects of the present disclosure. The operations of method 1600 may be implemented by a network entity or components thereof as described herein. For example, the operations of method 1600 may be performed by a network entity as described with reference to Figures 1 to 4 and Figures 9 to 12 the described network entity. In some examples, the network entity may execute an instruction set to control functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform aspects of the described functions.

[0218] At 1605, the method may include sending control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE. The operation of 1605 may be performed in accordance with examples disclosed herein. In some examples, aspects of the operation of 1605 may be performed by the control signaling component 1125 as described with reference to Figure 11 the described control signaling component 1125.

[0219] At 1610, the method may include receiving a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being based on the indicated number of transmit antennas at the network entity. The operation at 1610 may be performed according to the examples disclosed herein. In some examples, aspects of the operation at 1610 may be performed by the CSI reporting component 1130 as described with reference to Figure 11 the CSI reporting component 1130 described.

[0220] At 1615, the method may include communicating with the UE based on the set of one or more CSI parameters indicated via the CSI report. The operation at 1615 may be performed according to the examples disclosed herein. In some examples, aspects of the operation at 1615 may be performed by the communication component 1135 as described with reference to Figure 11 the communication component 1135 described.

[0221] At 1620, the method may include receiving, after receiving the CSI report, a second CSI report indicating a second set of one or more CSI parameters, wherein the difference between the set of one or more CSI parameters indicated via the CSI report and the second set of one or more CSI parameters indicated via the second CSI report is based on the number of antennas at the network entity and a change in one or more channel parameters associated with the communication between the network entity and the UE. The operation at 1620 may be performed according to the examples disclosed herein. In some examples, aspects of the operation at 1620 may be performed by the CSI reporting component 1130 as described with reference to Figure 11 the CSI reporting component 1130 described.

[0222] At 1625, the method may include transmitting a second downlink transmission based on the second set of one or more CSI parameters indicated via the second CSI report. The operation at 1625 may be performed according to the examples disclosed herein. In some examples, aspects of the operation at 1625 may be performed by the downlink transmission component 1140 as described with reference to Figure 11 the downlink transmission component 1140 described.

[0223] An overview of aspects of the present disclosure is provided below:

[0224] Aspect 1: A method for wireless communication at a UE, the method comprising: receiving control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE; transmitting a CSI report including a set of one or more CSI parameters, the set of one or more CSI parameters being at least partially based on the indicated number of transmit antennas at the network entity; and communicating with the network entity at least partially based on the set of one or more CSI parameters indicated via the CSI report.

[0225] Aspect 2: The method according to aspect 1, wherein receiving the control signaling comprises: receiving a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

[0226] Aspect 3: The method according to aspect 2, wherein receiving the plurality of control messages comprises: receiving the plurality of control messages periodically, wherein each of the plurality of control messages indicates a corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

[0227] Aspect 4: The method according to aspect 2, wherein receiving the plurality of control messages comprises: receiving the plurality of control messages aperiodically or periodically, wherein one or more of the plurality of control messages indicate corresponding changes in the number of transmit antennas activated at the network entity.

[0228] Aspect 5: The method according to any one of aspects 1 to 4, wherein receiving the control signaling comprises: receiving DCI indicating the number of transmit antennas.

[0229] Aspect 6: The method according to any one of aspects 1 to 4, wherein receiving the control signaling comprises: receiving RRC signaling indicating the number of transmit antennas.

[0230] Aspect 7: The method according to any one of aspects 1 to 6, the method further comprising: switching at least partially based on the indicated number of transmit antennas from a first demodulator among a plurality of demodulators of the UE to a second demodulator among the plurality of demodulators.

[0231] Aspect 8: The method according to aspect 7, the method further comprising: identifying the number of spatial streams associated with the downlink transmission; selecting the second demodulator from the plurality of demodulators of the UE for demodulating the downlink transmission at least partially based on a relationship between the indicated number of transmit antennas and the number of spatial streams associated with the downlink transmission, wherein switching from the first demodulator to the second demodulator is at least partially based on the selection of the second demodulator; receiving the downlink transmission; and demodulating the downlink transmission using the selected demodulator.

[0232] Aspect 9: The method according to aspect 7, wherein each of the plurality of demodulators of the UE is associated with a respective demodulation complexity, and wherein the method further comprises: determining that the number of indicated transmit antennas is at least a threshold number or a threshold ratio greater than the number of spatial streams associated with the downlink transmission; and selecting, at least in part based on the determination, the second demodulator associated with a second complexity, the second complexity being less than a first complexity associated with the first demodulator and one or more other complexities associated with one or more other demodulators of the plurality of demodulators, wherein switching from the first demodulator to the second demodulator is at least in part based on the selection of the second demodulator.

[0233] Aspect 10: The method according to any one of aspects 1 to 9, the method further comprising: detecting a change in one or more channel parameters associated with the communication between the UE and the network entity; and transmitting a second CSI report in response to detecting the change to indicate a second set of one or more CSI parameters, wherein the difference between the set of one or more CSI parameters and the second set of one or more CSI parameters is at least in part based on the number of indicated antennas at the network entity and the change in the one or more channel parameters.

[0234] Aspect 11: The method according to any one of aspects 1 to 10, the method further comprising: determining, at least in part based on conditions at the UE and the number of indicated transmit antennas at the network entity, the set of one or more CSI parameters, wherein the value of each CSI parameter in the set of one or more CSI parameters is related to the number of transmit antennas at the network entity.

[0235] Aspect 12: The method according to any one of aspects 1 to 11, wherein the set of one or more CSI parameters includes a PMI, a rank, an MCS, or any combination thereof for receiving the downlink transmission.

[0236] Aspect 13: A method for wireless communication at a network entity, the method comprising: transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a UE; receiving a CSI report comprising a set of one or more CSI parameters, the set of one or more CSI parameters being at least in part based on the number of indicated transmit antennas at the network entity; and communicating with the UE at least in part based on the set of one or more CSI parameters indicated via the CSI report.

[0237] Aspect 14: The method according to aspect 13, wherein transmitting the control signaling includes: transmitting a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of the transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

[0238] Aspect 15: The method according to aspect 14, wherein transmitting the plurality of control messages includes: transmitting the plurality of control messages periodically, wherein each of the plurality of control messages indicates the corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

[0239] Aspect 16: The method according to aspect 14, wherein transmitting the plurality of control messages includes: determining a change in the number of the transmit antennas activated at the network entity; and transmitting a control message among the plurality of control messages to indicate the change in the number of the transmit antennas, wherein the plurality of control messages are transmitted non-periodically or periodically, and wherein one or more of the plurality of control messages indicate the corresponding change in the number of the transmit antennas at the network entity.

[0240] Aspect 17: The method according to any one of aspects 13 to 16, wherein transmitting the control signaling includes: transmitting DCI indicating the number of the transmit antennas.

[0241] Aspect 18: The method according to any one of aspects 13 to 16, wherein transmitting the control signaling includes: transmitting RRC signaling indicating the number of the transmit antennas.

[0242] Aspect 19: The method according to any one of aspects 13 to 18, the method further includes: receiving a second CSI report indicating a second set of one or more CSI parameters after receiving the CSI report, wherein a difference between the set of one or more CSI parameters indicated via the CSI report and the second set of one or more CSI parameters indicated via the second CSI report is at least partially based on a change in the number of the antennas at the network entity and one or more channel parameters associated with communication between the network entity and the UE; and transmitting a second downlink transmission at least partially based on the second set of one or more CSI parameters indicated via the second CSI report.

[0243] Aspect 20: The method according to any one of aspects 13 to 19, wherein the value of each CSI parameter in the set of one or more CSI parameters is related to the number of transmit antennas at the network entity.

[0244] Aspect 21: The method according to any one of aspects 13 to 20, wherein the set of one or more CSI parameters includes a PMI, a rank, an MCS, or any combination thereof for transmitting the downlink transmission.

[0245] Aspect 22: An apparatus for wireless communication at a UE, the apparatus 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 12.

[0246] Aspect 23: An apparatus for wireless communication at a UE, comprising at least one component for performing the method according to any one of aspects 1 to 12.

[0247] Aspect 24: 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 12.

[0248] Aspect 25: An apparatus for wireless communication at a network entity, the apparatus 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 13 to 21.

[0249] Aspect 26: An apparatus for wireless communication at a network entity, comprising at least one component for performing the method according to any one of aspects 13 to 21.

[0250] Aspect 27: A non-transitory computer-readable medium storing code for wireless communication at a network entity, the code including instructions executable by a processor to perform the method according to any one of aspects 13 to 21.

[0251] It should be noted that the methods described herein describe possible specific implementations, and the operations and steps may be rearranged or otherwise modified and other specific implementations are also possible. In addition, aspects from two or more methods may be combined.

[0252] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes and the terms LTE, LTE-A, LTE-A Pro, or NR may be used in most of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various 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.

[0253] 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 referred to throughout the specification may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0254] The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed using a general-purpose processor, DSP, ASIC, CPU, 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. The 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).

[0255] The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. When implemented using software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted using one or more instructions or codes on a computer-readable medium. Other examples and specific 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 may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination of these items. The features implementing the functions may also be physically located at different positions, including being distributed such that portions of the functions are implemented at different physical locations.

[0256] A computer-readable medium includes both a non-transitory computer storage medium and a communication medium, which includes any medium that facilitates transfer of a computer program from one location 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, non-transitory computer-readable media can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (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 components in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer or a general purpose or special purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of 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. A disk can magnetically reproduce data, while a disc can optically reproduce data using lasers. Combinations of the above are also included within the scope of computer-readable medium.

[0257] As used herein (including in the claims), the "or" used in a list of items (e.g., a list of items accompanied by a phrase such as "at least one of" or "one or more of") indicates an inclusive listing such that, for example, a listing of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Additionally, as used herein, the phrase "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". Similarly, as used herein, the phrase "set" should be understood to include the possibility of a set having one member. That is, the phrase "set" should be interpreted in the same manner as "one or more".

[0258] The term "determine" encompasses a variety of actions, and thus, "determine" can include operations such as calculating, computing, processing, deriving, investigating, looking up (such as looking up in a table, database, or other data structure), ascertaining, and the like. Additionally, "determine" can include receiving (e.g., receiving information), accessing (e.g., accessing data stored in a memory), etc. Further, "determine" can include parsing, obtaining, selecting, choosing, establishing, and other such similar actions.

[0259] In the drawings, like components or features may have the same reference numerals. Additionally, various components of the same type can be distinguished by adding a dash and a second numeral used to differentiate between like components after the reference numeral. If only the first reference numeral is used in the specification, the description can apply to any one of the like components having the same first reference numeral, regardless of the second reference numeral or any other subsequent reference numerals.

[0260] The description set forth herein in connection with the drawings describes example configurations and does not represent all examples that may be implemented or that 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". The detailed description includes specific details for providing an understanding of the described techniques. However, the techniques 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.

[0261] The description provided herein enables a person of ordinary skill in the art to make or use the present disclosure. Various modifications to the present disclosure are readily apparent to those of ordinary skill in the art, and the general principles defined herein can 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), the apparatus 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: receive control signaling indicating the number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE; transmit a channel state information report including a set of one or more channel state information parameters, the set of one or more channel state information parameters being at least partially based on the indicated number of transmit antennas at the network entity; and communicate with the network entity at least partially based on the set of one or more channel state information parameters indicated via the channel state information report.

2. The apparatus according to claim 1, wherein, to receive the control signaling, the instructions are executable by the processor to cause the apparatus to: receive a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

3. The apparatus according to claim 2, wherein, to receive the plurality of control messages, the instructions are executable by the processor to cause the apparatus to: receive the plurality of control messages periodically, wherein each of the plurality of control messages indicates the corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

4. The apparatus according to claim 2, wherein, to receive the plurality of control messages, the instructions are executable by the processor to cause the apparatus to: receive the plurality of control messages aperiodically or periodically, wherein one or more of the plurality of control messages indicate corresponding changes in the number of transmit antennas activated at the network entity.

5. The apparatus according to claim 1, wherein, to receive the control signaling, the instructions are executable by the processor to cause the apparatus to: receive downlink control information indicating the number of transmit antennas.

6. The apparatus according to claim 1, wherein, to receive the control signaling, the instructions are executable by the processor to cause the apparatus to: receive radio resource control signaling indicating the number of transmit antennas.

7. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: switch from a first demodulator among a plurality of demodulators of the UE to a second demodulator among the plurality of demodulators at least partially based on the indicated number of transmit antennas.

8. The apparatus according to claim 7, wherein the instructions are further executable by the processor to cause the apparatus to: Identify the number of spatial streams associated with the downlink transmission; Select the second demodulator from the plurality of demodulators of the UE for demodulating the downlink transmission at least in part based on a relationship between the indicated number of transmit antennas and the number of spatial streams associated with the downlink transmission, wherein switching from the first demodulator to the second demodulator is at least in part based on the selection of the second demodulator; Receive the downlink transmission; And Demodulate the downlink transmission using the selected demodulator.

9. The apparatus according to claim 7, wherein each demodulator of the plurality of demodulators of the UE is associated with a respective demodulation complexity, and wherein the instructions are further executable by the processor to cause the apparatus to: Determine that the indicated number of transmit antennas is greater than the number of spatial streams associated with the downlink transmission by at least a threshold number or a threshold ratio; and Select the second demodulator associated with a second complexity at least in part based on the determination, the second complexity being less than a first complexity associated with the first demodulator and one or more other complexities associated with one or more other demodulators of the plurality of demodulators, wherein switching from the first demodulator to the second demodulator is at least in part based on the selection of the second demodulator.

10. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: Detect a change in one or more channel parameters associated with communication between the UE and the network entity; and Transmit a second channel state information report in response to detecting the change to indicate a second set of one or more channel state information parameters, wherein a difference between the set of one or more channel state information parameters and the second set of one or more channel state information parameters is at least in part based on the indicated number of antennas at the network entity and the change in the one or more channel parameters.

11. The apparatus according to claim 1, wherein the instructions are further executable by the processor to cause the apparatus to: Determine the set of one or more channel state information parameters at least in part based on conditions at the UE and the indicated number of transmit antennas at the network entity, wherein a value of each channel state information parameter in the set of one or more channel state information parameters is related to the number of transmit antennas at the network entity.

12. The apparatus according to claim 1, wherein the set of one or more channel state information parameters includes a precoding matrix indicator, a rank, a modulation and coding scheme, or any combination thereof for receiving the downlink transmission.

13. An apparatus for wireless communication at a network entity, the apparatus Comprises: A processor; A memory coupled to the processor; And Instructions stored in the memory and executable by the processor to cause the apparatus to: Send control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a user equipment (UE); Receive a channel state information report including a set of one or more channel state information parameters, the set of one or more channel state information parameters being at least partially based on the indicated number of transmit antennas at the network entity; And Communicate with the UE at least partially based on the set of one or more channel state information parameters indicated via the channel state information report.

14. The apparatus according to claim 13, Wherein, To send the control signaling, the instructions can be executed by the processor to cause the apparatus to: Send a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

15. The apparatus according to claim 14, Wherein, To send the plurality of control messages, the instructions can be executed by the processor to cause the apparatus to: Periodically send the plurality of control messages, wherein each of the plurality of control messages indicates the corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

16. The apparatus according to claim 14, Wherein, To send the plurality of control messages, the instructions can be executed by the processor to cause the apparatus to: Determine a change in the number of transmit antennas activated at the network entity; And Send a control message among the plurality of control messages to indicate the change in the number of transmit antennas, wherein the plurality of control messages are sent non-periodically or periodically, and wherein one or more of the plurality of control messages indicate the corresponding change in the number of transmit antennas at the network entity.

17. The apparatus according to claim 13, Wherein, To send the control signaling, the instructions can be executed by the processor to cause the apparatus to: Send downlink control information indicating the number of transmit antennas.

18. The apparatus according to claim 13, wherein to send the control signaling, the instructions can be executed by the processor to cause the apparatus to: Send radio resource control signaling indicating the number of transmit antennas.

19. The apparatus according to claim 13, wherein the instructions can be further executed by the processor to cause the apparatus to: Receiving, after receiving the channel state information report, a second channel state information report indicating a second set of one or more channel state information parameters, wherein a difference between the set of one or more channel state information parameters indicated via the channel state information report and the second set of one or more channel state information parameters indicated via the second channel state information report is at least partially based on a number of the antennas at the network entity and a change in one or more channel parameters associated with communication between the network entity and the UE; and Transmitting a second downlink transmission at least partially based on the second set of one or more channel state information parameters indicated via the second channel state information report.

20. The apparatus according to claim 13, wherein a value of each channel state information parameter in the set of one or more channel state information parameters is related to a number of the transmit antennas at the network entity.

21. The apparatus according to claim 13, wherein the set of one or more channel state information parameters includes a precoding matrix indicator, a rank, a modulation and coding scheme, or any combination thereof for transmitting the downlink transmission.

22. A method for wireless communication at a user equipment (UE), the method comprising: Receiving control signaling indicating a number of transmit antennas at a network entity, the number of transmit antennas including antennas activated for downlink transmission to the UE; Transmitting a channel state information report including a set of one or more channel state information parameters, the set of one or more channel state information parameters being at least partially based on the indicated number of transmit antennas at the network entity; and Communicating with the network entity at least partially based on the set of one or more channel state information parameters indicated via the channel state information report.

23. The method according to claim 22, wherein receiving the control signaling comprises: Receiving a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of the transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

24. The method according to claim 23, wherein receiving the plurality of control messages comprises: Receiving the plurality of control messages periodically, wherein each of the plurality of control messages indicates a corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

25. The method according to claim 23, wherein receiving the plurality of control messages comprises: Receiving the plurality of control messages aperiodically or periodically, wherein one or more of the plurality of control messages indicate corresponding changes in the number of the transmit antennas activated at the network entity.

26. The method according to claim 22, the method further comprises: switching from a first demodulator among a plurality of demodulators of the UE to a second demodulator among the plurality of demodulators at least partially based on the indicated number of transmit antennas.

27. A method for wireless communication at a network entity, the method comprises: transmitting control signaling indicating the number of transmit antennas at the network entity, the number of transmit antennas including antennas activated for downlink transmission to a user equipment (UE); receiving a channel state information report including a set of one or more channel state information parameters, the set of one or more channel state information parameters being at least partially based on the indicated number of transmit antennas at the network entity; and communicating with the UE at least partially based on the set of one or more channel state information parameters indicated via the channel state information report.

28. The method according to claim 27, wherein transmitting the control signaling comprises: transmitting a plurality of control messages, wherein a first control message among the plurality of control messages indicates the number of transmit antennas activated at the network entity at a first time, and wherein one or more other control messages among the plurality of control messages indicate one or more other numbers of transmit antennas activated at the network entity at one or more other times different from the first time.

29. The method according to claim 28, wherein transmitting the plurality of control messages comprises: periodically transmitting the plurality of control messages, wherein each of the plurality of control messages indicates the corresponding number of transmit antennas activated at the network entity during a corresponding time period associated with the periodicity of the plurality of control messages.

30. The method according to claim 28, wherein transmitting the plurality of control messages comprises: determining a change in the number of transmit antennas activated at the network entity; and transmitting a control message among the plurality of control messages to indicate the change in the number of transmit antennas, wherein the plurality of control messages are transmitted non-periodically or periodically, and wherein one or more of the plurality of control messages indicate the corresponding change in the number of transmit antennas at the network entity.

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