Determining subband size for channel state information reporting based on active antenna port configuration

Abstract

Methods, systems, and devices for wireless communication are described. In some systems, a user equipment (UE) may update channel state information (CSI) reporting granularity based on antenna port configuration updates using a mapping. For example, the UE may store mappings from different antenna port configurations to corresponding sub-band sizes for CSI reporting. In some examples, the network entity may configure the UE to have the mapping. In some other examples, the UE may be pre-configured with the mapping. If the UE receives control signaling indicating an antenna port configuration update at the network entity, such as downlink control information (DCI) signaling, the UE may use the mapping to determine a corresponding update to a sub-band size granularity for CSI reporting. The UE may perform a CSI measurement on a reference signal using the determined sub-band size and report the CSI measurement to the network entity in a CSI report.

Description

[0001] Cross-references

[0002] This patent application claims the benefit of U.S. patent application No. 17 / 894,708, entitled “DETERMINING ASUB-BAND SIZE FOR CHANNEL STATE INFORMATON REPORTING BASED ON AN ACTIVEANTENNA PORT CONFIGURATION,” filed by ABOTABL et al. on August 24, 2022, which is assigned to the assignee of this application and is expressly incorporated herein by reference in its entirety. Technical Field

[0003] The following relates to wireless communications, including determining a subband size for channel state information (CSI) reporting based on an active antenna port configuration. Background Art

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, and the like. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as new radio (NR) systems). These systems may employ techniques 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 multiple access communication system may include one or more base stations, each of which supports wireless communication of a communication device, which may be referred to as a user equipment (UE).

[0005] In some wireless communication systems, a network entity, such as a base station or a radio unit (RU), may include a relatively large number of antenna ports to support massive multiple-input multiple-output (MIMO) communications and other specific implementations. However, operating with a relatively large number of antenna ports may result in a correspondingly high network energy consumption (e.g., greater than an energy overhead threshold) of a radio access network (RAN). Such high network energy consumption of the RAN may potentially limit the adoption and expansion of cellular networks, for example, for massive MIMO communications. Summary of the invention

[0006] The systems, methods and devices of the present disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.

[0007] One innovative aspect of the subject matter described in the present disclosure can be implemented in a method for wireless communication at a user equipment (UE). The method includes: receiving a control signal indicating an updated antenna port configuration for the network entity from a network entity; and receiving a set of multiple reference signals from the network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting channel state information (CSI). The method also includes: sending a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0008] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication at a UE. The apparatus includes a processor and a memory coupled to the processor. The memory stores instructions executable by the processor to cause the apparatus to: receive a control signal indicating an updated antenna port configuration for the network entity from a network entity; and based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI, receive a set of multiple reference signals from the network entity. The memory stores instructions further executable by the processor to cause the apparatus to: send a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0009] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication at a UE. The apparatus includes: a component for receiving a control signal indicating an updated antenna port configuration for the network entity from a network entity; and a component for receiving a set of multiple reference signals from the network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The apparatus also includes: a component for sending a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0010] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a non-transitory computer-readable medium storing code for wireless communication at a UE. The code includes instructions executable by a processor to: receive a control signal indicating an updated antenna port configuration for the network entity from a network entity; and based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI, receive a set of multiple reference signals from the network entity. The code includes instructions further executable by the processor to: send a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0011] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a method for wireless communication at a network entity. The method includes: sending a control signal indicating an updated antenna port configuration for the network entity; and sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The method also includes: receiving the CSI report including a CSI measurement, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0012] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication at a network entity. The apparatus includes a processor and a memory coupled to the processor. The memory stores instructions executable by the processor to cause the apparatus to: send a control signal indicating an updated antenna port configuration for the network entity; and send a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The memory stores instructions further executable by the processor to cause the apparatus to: receive the CSI report including a CSI measurement based on the subband size and the set of multiple reference signals.

[0013] Another innovative aspect of the subject matter described in the present disclosure can be implemented in an apparatus for wireless communication at a network entity. The apparatus includes: a component for sending a control signal indicating an updated antenna port configuration for the network entity; and a component for sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The apparatus also includes: a component for receiving the CSI report including a CSI measurement, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0014] Another innovative aspect of the subject matter described in the present disclosure can be implemented in a non-transitory computer-readable medium storing code for wireless communication at a network entity. The code includes instructions executable by a processor to: send a control signal indicating an updated antenna port configuration for the network entity; and send a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The code includes instructions further executable by the processor to: receive the CSI report including a CSI measurement, the CSI measurement being based on the subband size and the set of multiple reference signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 An example of a wireless communication system that supports determining a subband size for channel state information (CSI) reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is illustrated.

[0016] Figure 2 An example of a network architecture that supports determining a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is illustrated.

[0017] Figure 3 An example of a wireless communication system supporting determination of a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is illustrated.

[0018] Figure 4 An example of a process flow supporting determination of subband size for CSI reporting based on active antenna port configuration in accordance with one or more aspects of the present disclosure is illustrated.

[0019] Figure 5 and Figure 6 A block diagram of an apparatus supporting determination of subband size for CSI reporting based on active antenna port configuration in accordance with one or more aspects of the present disclosure is shown.

[0020] Figure 7 A block diagram of a communications manager that supports determining subband sizes for CSI reporting based on active antenna port configurations in accordance with one or more aspects of the present disclosure is shown.

[0021] Figure 8 A diagram of a system including a device that supports determining a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is shown.

[0022] Fig. 9 and Fig.10A block diagram of an apparatus supporting determination of subband size for CSI reporting based on active antenna port configuration in accordance with one or more aspects of the present disclosure is shown.

[0023] Fig.11 A block diagram of a communications manager that supports determining subband sizes for CSI reporting based on active antenna port configurations in accordance with one or more aspects of the present disclosure is shown.

[0024] Fig.12 A diagram of a system including a device that supports determining a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is shown.

[0025] Figures 13 to 17 A flow chart illustrating a method for supporting determination of subband size for CSI reporting based on active antenna port configuration according to one or more aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0026] In some wireless communication systems, a network entity may dynamically update (or "adapt") the antenna port configuration to support power conservation. For example, the network entity may deactivate a certain number of antenna ports to save energy, or may activate a certain number of antenna ports to support connections with one or more additional wireless devices, such as user equipment (UE). The network entity may send an indication of an antenna port configuration update (or "change") to the UE via signaling, such as downlink control information (DCI) signaling, medium access control (MAC) control element (CE) signaling, or other control signaling, so that the UE may communicate with the network entity based on the updated antenna port configuration. However, updates to the antenna port configuration at the network entity may also affect channel state information (CSI) reporting by the UE. CSI reporting by the UE may be based on CSI reporting parameters configured by the network entity using other control signaling, such as radio resource control (RRC) signaling. Because DCI signaling supports relatively lower latency communications than RRC signaling, the network entity may dynamically update the network entity's antenna port configuration according to a relatively shorter timeline than the network entity may reconfigure CSI reporting parameters using RRC signaling.

[0027] Various aspects relate generally to CSI reporting, and more specifically to determining a subband size for CSI reporting based on an active antenna port configuration. The subband size may determine the granularity for CSI reporting such that the CSI report includes CSI measurements corresponding to the corresponding subbands of the subband size. The UE may use a mapping to determine the subband size for CSI reporting corresponding to the active antenna port configuration at the network entity. If the network entity updates the active antenna port configuration and indicates the updated active antenna port configuration to the UE, the UE may update the subband size for CSI reporting accordingly according to the mapping. For example, the UE may store a mapping between the corresponding antenna port configuration and the corresponding subband size for CSI reporting. In some examples, the mapping may more specifically map the corresponding number of active antenna ports to the corresponding subband size. In some other examples, the mapping may more specifically map the corresponding type of antenna port configuration (e.g., primary antenna port configuration, one or more secondary antenna port configurations) to the corresponding subband size. In yet other examples, the UE may use a scaling operation to determine the mapping from the corresponding antenna port configuration to the corresponding subband size. The subband size for CSI reporting indicated by the mapping may be the same or different for a channel quality information (CQI) report and a precoding matrix indicator (PMI) report, among other specific implementations. In some examples, a network entity may configure a UE using a mapping, a scaling operation, or both (e.g., via RRC signaling). In such examples, if a UE receives a control signal (e.g., DCI signaling) indicating an antenna port configuration update at the network entity, the UE may use the mapping to determine a corresponding update to the subband size for CSI reporting. The UE may use the determined subband size for CSI reporting, including performing CSI measurements on a CSI reference signal (CSI-RS), and determining a granularity for reporting CSI measurements (such as CQI, PMI, or both (and other parameters)) in a CSI report sent by the UE to the network entity. In some examples, the granularity of the CSI report may be based on the subband size, such that the CSI report includes multiple CSI measurement values, and each CSI measurement value corresponds to a bandwidth of the determined subband size.

[0028] Certain aspects of the subject matter described in the present disclosure may be implemented to achieve one or more of the following potential advantages. By using a mapping from different antenna port configurations to corresponding subband sizes for CSI reporting, a UE is able to dynamically update subband sizes for CSI reporting (e.g., CSI-RS reception, CSI measurement, and determination of granularity of CSI reporting, such as PMI reporting, CQI reporting, or both) in response to a dynamic update of the antenna port configuration performed by a network entity. This enables the UE to update the granularity of CSI reporting without RRC reconfiguration of CSI reporting parameters, thereby improving latency and reducing signaling overhead associated with updating the granularity of CSI reporting, among other benefits. Such updates to the granularity of CSI reporting based on the mapping may also improve the accuracy of CSI reporting by the UE. For example, if the network entity reduces the number of active antenna ports, the mapping may allow the UE to correspondingly increase the subband size used for CSI reporting, reduce processing and signaling overhead associated with CSI reporting, reconfiguration of CSI reporting parameters, or both, while maintaining CSI reporting accuracy (e.g., satisfying an accuracy threshold) according to the updated number of active antenna ports. Additionally or alternatively, if the network entity increases the number of active antenna ports, the mapping may allow the UE to correspondingly reduce the subband size used for CSI reporting, thereby supporting relatively finer CSI reporting according to the updated number of active antenna ports and correspondingly supporting relatively more accurate precoding for communication between the UE and the network entity.

[0029] Aspects of the present disclosure are first described in the context of a wireless communication system. Aspects of the present disclosure are further illustrated and described by and with reference to process flows, apparatus diagrams, system diagrams, and flowcharts related to subband sizes for CSI reporting adapted based on antenna port configuration.

[0030] Figure 1 An example of a wireless communication system 100 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to 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 advanced LTE (LTE-A) network, an LTE-A Pro network, a new radio (NR) network, or a network operating according to other systems and radio technologies (including future systems and radio technologies not explicitly mentioned herein).

[0031] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100, and may include devices in different forms or with 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 nomenclature. In some examples, the network entities 105 and the UE 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), over which the UE 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 in which the network entity 105 and the UE 115 may support signal communications according to one or more radio access technologies (RATs).

[0032] 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 stationary and mobile at different times. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. UE 115 may be capable of supporting communication with various types of devices, such as Figure 1 Communicate with other UEs 115 or network entities 105) as shown.

[0033] The 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, a UE 115, a network controller, a device, an equipment, a computing system, one or more components, or another suitable processing entity. For example, the node may be a UE 115. As another example, the node may be a network entity 105. As 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 relative to these examples. Similarly, references to UE 115, network entity 105, devices, equipment, or computing systems may include disclosure that UE 115, network entity 105, devices, equipment, or computing systems are nodes. For example, the disclosure that the UE 115 is configured to receive information from the network entity 105 also discloses that the first node is configured to receive information from the second node.

[0034] In some examples, the network entities 105 may communicate with the core network 130, or with each other, or both. For example, the network entities 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 entities 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 entities 105 may communicate with each other via midhaul communication links 162 (e.g., according to a midhaul interface protocol) or fronthaul communication links 168 (e.g., according to a fronthaul interface protocol) or any combination thereof. The backhaul communication links 120, midhaul communication links 162, or fronthaul communication links 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. UE 115 may communicate with core network 130 via communication link 155 .

[0035] One or more of the network entities 105 may include or may be referred to as a base station 140 (e.g., a transceiver base station, a radio base station, an NR base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a next generation NodeB or a giga NodeB (any of which may be referred to as a gNB), a 5G NB, a next generation eNB (ng-eNB), a home NodeB, a home eNodeB, or other suitable terms). In some examples, the network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, standalone) base station architecture, which may be configured to utilize a protocol stack that is physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140).

[0036] In some examples, the network entity 105 can be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) that can be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 105 can 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., a near real-time RIC (near RT RIC), a 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, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmit receive point (TRP). One or more components of the network entity 105 in the decomposed 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 the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0037] The functional split between CU 160, DU 165, and RU 170 is flexible and may support different functionalities, depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof) are performed at CU 160, DU 165, and RU 170. For example, a functional split of a protocol stack may be employed between CU 160 and DU 165, such that CU 160 may support one or more layers of a protocol stack and DU 165 may support one or more different layers of a protocol stack. In some examples, CU 160 may host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functionality and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 may be connected to one or more DUs 165 or RUs 170, and the one or more DUs 165 or RUs 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, MAC layer) functionality and signaling, and may each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack may be employed between the DU 165 and the RU 170, such that the DU 165 may support one or more layers of the protocol stack, and the RU 170 may support one or more different layers of the protocol stack. The DU 165 may support one or more different cells (e.g., via one or more RUs 170). In some implementations, the functional split between the CU 160 and the DU 165 or between the DU 165 and the RU 170 may be within the protocol layer (e.g., some functions of the protocol layer may be performed by one of the CU 160, DU 165, or RU 170, while other functions of the protocol layer are performed by the other of the CU 160, DU 165, or RU 170). The CU 160 may be further functionally split into CU control plane (CU-CP) and CU user plane (CU-UP) functions. The CU 160 may be connected to one or more DUs 165 via midhaul communication links 162 (e.g., F1, F1-c, F1-u), and the DU 165 may be connected to one or more RUs 170 via fronthaul communication links 168 (e.g., open fronthaul (FH) interface). In some examples, midhaul communication link 162 or fronthaul communication link 168 may be implemented based on an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 105 that communicate via such communication links.

[0038] In some wireless communication systems (e.g., wireless communication system 100), infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, thereby providing an IAB network architecture (e.g., to core network 130). In some specific implementations, in an IAB network, one or more network entities 105 (e.g., IAB nodes 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 controlled in part by one or more CUs 160 associated with a host network entity 105 (e.g., a host base station 140). One or more host network entities 105 (e.g., an IAB host) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a DU 165 of a coupled IAB host. The IAB-MT may include an independent set of antennas for relaying communications with the UE 115, or may share the same antennas of the IAB node 104 (e.g., of the RU 170) 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 node 104, UE 115) within a relay chain or configuration (e.g., downstream) of the access network. In such specific implementations, one or more components of the decomposed RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to a technique that supports subband size determination for CSI reporting.

[0039] One or more components of the decomposed RAN architecture may be configured to support determining the subband size for CSI reporting based on antenna port configuration adaptation. 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 decomposed RAN architecture (e.g., the IAB node 104, the DU 165, the CU 160, the RU 170, the RIC 175, the SMO 180).

[0040] 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 terminology, where a "device" may also be referred to as a unit, a station, a terminal, or a client, etc. 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, 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.

[0041] The UE 115 may be able to communicate with various types of devices, such as other UEs 115, which 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. Figure 1 shown.

[0042] The UE 115 and the network entity 105 may wirelessly communicate 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 collection of RF spectrum resources having a physical layer structure defined for supporting the communication link 125. For example, a carrier for the communication link 125 may include a portion of an RF spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communications with the UE 115 using carrier aggregation or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between the device and any part (e.g., entity, sub-entity) of the network entity 105. For example, the terms "sending," "receiving," or "communicating" when referring to the network entity 105 may refer to any part of the network entity 105 (e.g., base station 140, CU 160, DU 165, RU 170) of the RAN communicating with another device (e.g., directly or via one or more other network entities 105).

[0043] In some examples, such as in a carrier aggregation configuration, a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. A carrier may be associated with a frequency channel (e.g., an 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 a standalone mode, in which case initial acquisition and connection may be performed by UE 115 via the carrier, or a carrier may operate in a non-standalone mode, in which case the connection is anchored using a different carrier (e.g., a different carrier of the same or different radio access technology).

[0044] The communication link 125 shown in the wireless communication system 100 may include downlink transmissions (e.g., forward link transmissions) from the network entity 105 to the UE 115, uplink transmissions (e.g., return link transmissions) from the UE 115 to the network entity 105, or both, as well as other transmission configurations. A carrier may carry downlink or uplink communications (e.g., in FDD mode), or may be configured to carry both downlink and uplink communications (e.g., in TDD mode).

[0045] A carrier may be associated with a particular bandwidth of the RF spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of a set of bandwidths of carriers for 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). A device of the wireless communication system 100 (e.g., a network entity 105, a UE 115, or both) may have a hardware configuration that supports communication using a particular carrier bandwidth, or may be configured to support communication using one of the carrier bandwidths in the 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., a subband, a BWP) or all of the carrier bandwidth.

[0046] The signal waveform transmitted via the carrier may be composed of 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 MCM techniques, a resource element may refer to a 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 coding rate of the modulation scheme, or both), so that a relatively high number of resource elements (e.g., in 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 layers, beams), and the use of multiple spatial resources may increase the data rate or data integrity of communications with UE 115.

[0047] One or more parameter sets for a carrier may be supported, and the parameter sets may include subcarrier spacing (Δf) and cyclic prefixes. A carrier may be divided into one or more BWPs with the same or different parameter sets. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time, and communications of a UE 115 may be constrained to one or more active BWPs.

[0048] The time interval for the network entity 105 or the UE 115 may be expressed in multiples of a basic time unit, which may be, for example, a sampling period T s =1 / (Δf max ·N f ) seconds, where Δf max It can represent the supported subcarrier spacing, and N f The supported discrete Fourier transform (DFT) size may be indicated. The time intervals of the communication resources may be organized according to radio frames each having a specific duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0049] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, the frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into multiple time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include multiple symbol periods (e.g., depending on the length of the cyclic prefix added before each symbol period). In some wireless communication systems 100, the time slot may be further divided into multiple micro time slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N f ) sampling period. The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0050] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may 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) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in the form of a burst of shortened TTIs (sTTIs)).

[0051] Physical channels may be multiplexed according to various techniques in order to communicate using a carrier. For example, physical control channels and physical data channels may be multiplexed using one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique to signal via a downlink carrier. A control region (e.g., a control resource set (CORESET)) for a physical control channel may be defined by a set of symbol periods and may extend across a system bandwidth or a portion of a system bandwidth of a carrier. One or more control regions (e.g., CORESETs) may be configured for a group of UEs 115. For example, one or more UEs in UE 115 may monitor or search a control region for control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level for a control channel candidate may refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for transmitting control information to a plurality of UEs 115 , and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0052] In some examples, the network entities 105 (e.g., base stations 140, RUs 170) may be mobile and provide communication coverage for mobile coverage areas 110. In some examples, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communication system 100 may include, for example, a heterogeneous network in which different types of network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

[0053] The wireless communication system 100 can be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 can be configured to support ultra-reliable low-latency communication (URLLC). UE 115 can be designed to support ultra-reliable, low-latency or critical functions. Ultra-reliable communication may include private communication or group communication, and may be supported by one or more services (such as push-to-talk, video or data). Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency and ultra-reliable low-latency may be used interchangeably herein.

[0054] In some examples, the UE 115 may be configured to support communication directly 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 in a group that are performing D2D communication may be within a coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), which 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 of 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, in which each UE 115 transmits to each of the other UEs 115 in the group. In some examples, network entity 105 may facilitate scheduling of resources for D2D communications. In some other examples, D2D communications may be performed between UEs 115 without involving network entity 105.

[0055] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include control plane entities (e.g., mobility management entity (MME), access and mobility management function (AMF)) for managing access and mobility, and user plane entities (e.g., serving gateway (S-GW), packet data network (PDN) gateway (P-GW) or user plane function (UPF)) for routing packets or interconnections to external networks. The control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication and bearer management for UE 115 served by a network entity 105 (e.g., base station 140) associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the IP service 150 of one or more network operators. IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0056] The wireless communication system 100 may operate using one or more frequency bands that may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). In general, the region from 300 MHz to 3 GHz is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength range is about one decimeter to one meter. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clusters), but these waves may be sufficient to penetrate structures so that macro cells provide services to UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter distances (e.g., less than 100 kilometers) compared to communications using smaller frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0057] The wireless communication system 100 can utilize licensed and unlicensed RF spectrum bands. For example, the wireless communication system 100 can use unlicensed bands (such as the 5 GHz Industrial, Scientific, and Medical (ISM) band) to employ licensed assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology. When operating using unlicensed RF spectrum bands, devices such as network entity 105 and UE 115 can employ carrier sensing for conflict detection and avoidance. In some examples, operations using unlicensed bands can be based on a carrier aggregation configuration combined with component carriers operating using licensed bands (e.g., LAA). Operations performed using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among others.

[0058] The network entity 105 (e.g., base station 140, RU 170) or UE 115 may be equipped with multiple antennas that can be used to employ technologies such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the network entity 105 or UE 115 may be located in one or more antenna arrays or antenna panels, which may support MIMO operations 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, 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 collection of multiple rows and columns of antenna ports that the network entity 105 can use to support beamforming for communications with the UE 115. Similarly, the UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals sent via the antenna ports.

[0059] The network entity 105 or UE 115 may use MIMO communication to utilize multipath signal propagation and improve spectral efficiency by sending or receiving multiple signals via different spatial layers. Such a technology may be referred to as spatial multiplexing. Multiple signals may be, for example, sent by a transmitting device via different antennas or different combinations of antennas. Similarly, multiple signals may be received by a 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). Different spatial layers may be associated with different antenna ports for channel measurement and reporting. MIMO technologies include single-user MIMO (SU-MIMO), for which multiple spatial layers are sent to the same receiving device; and multi-user MIMO (MU-MIMO), for which multiple spatial layers are sent to multiple devices.

[0060] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that can be used at a transmitting device or a receiving device (e.g., a network entity 105, a 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 antenna elements of an antenna array so that some signals propagating in a particular direction relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals conveyed via antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each antenna element may be defined by a set of beamforming weights associated with a particular orientation (e.g., for an antenna array of a transmitting device or a receiving device, or for some other orientation).

[0061] The network entity 105 or UE 115 may use beam scanning techniques as part of a beamforming operation. For example, the 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 sent multiple times by the network entity 105 along different directions. For example, the network entity 105 may send signals according to different beamforming weight sets associated with different transmission directions. Transmissions along different beam directions may be used to identify beam directions (e.g., by a transmitting device (such as network entity 105) or by a receiving device (such as UE 115)) for later transmission or reception by the network entity 105.

[0062] 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, a 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 sent by network entity 105 along different directions, and may report to network entity 105 an indication of the signal received by UE 115 with the highest signal quality or other acceptable signal quality.

[0063] In some examples, transmission by a device (e.g., by network entity 105 or UE 115) may be performed 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 a system bandwidth or one or more subbands. Network entity 105 may send a reference signal (e.g., a cell-specific reference signal (CRS), a CSI reference signal (CSI-RS)), which may be precoded or non-precoded. UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook). Although these techniques are described with reference to signals sent along one or more directions by a network entity 105 (e.g., base station 140, RU 170), UE 115 may use similar techniques to send signals multiple times along different directions (e.g., to identify a beam direction for subsequent transmission or reception by UE 115), or to send signals along a single direction (e.g., to send data to a receiving device).

[0064] 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 reception according to multiple receiving directions by: receiving via different antenna subarrays, processing received signals according to different antenna subarrays, receiving according to different receiving beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or processing received signals according to different receiving beamforming weight sets applied to 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). A single receive configuration may be aligned along a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0065] The wireless communication system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or PDCP layer may be IP-based. The RLC layer may perform packet segmentation and reassembly to communicate via logical channels. The MAC layer may perform priority management and multiplexing of 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 the establishment, configuration, and maintenance of an RRC connection that supports a radio bearer for user plane data between the UE 115 and the network entity 105 or the core network 130. The PHY layer may map a transport channel to a physical channel.

[0066] UE 115 and network entity 105 may support retransmission of data to increase the likelihood that the data is successfully received. Hybrid automatic repeat request (HARQ) feedback is a technique for increasing the likelihood 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 a cyclic redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ may improve the throughput of the MAC layer in poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, a device may support same-slot HARQ feedback, in which case the device may provide HARQ feedback in a specific time slot for data received via a previous symbol in the time slot. In some other examples, the device may provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0067] A network entity 105 in the wireless communication system 100 may send a CSI reporting configuration to a UE 115. The CSI reporting configuration, which may be sent, for example, via an RRC signal, may indicate a CSI reporting setting for the UE 115. In some examples, the CSI reporting configuration may be configured by the RRC to be specific to each BWP. The CSI reporting configuration may configure one or more resource sets for CSI measurement (e.g., channel measurement, interference measurement), codebook configuration (e.g., codebook type, antenna configuration), reporting configuration type (e.g., periodic, semi-periodic, aperiodic), or any combination thereof. The resource sets indicated by the CSI reporting configuration may include K channels having the same number of ports. S resources, these ports may be referred to as antenna ports or CSI-RS ports. S The value of can indicate the threshold number of ports. For example, if K S =1, each resource may include up to 32 CSI-RS ports; if K S =2, each resource may include up to 16 CSI-RS ports; and if 2 <K S≤8, each resource may include up to 8 CSI-RS ports. A P-port resource may have ports (e.g., CSI-RS ports) labeled 3000 to 300(P-1). A codebook configuration (e.g., a PMI codebook report) may include a codebook type, such as a type I single-panel codebook, a type I multi-panel codebook, a type II single-panel codebook, a type II port selection codebook, a type II enhanced port selection codebook, or any other codebook type. The codebook configuration may additionally or alternatively include an antenna configuration. For example, a codebook type may support antenna element configuration (N1, N2), number of panels (N g ) and the corresponding number of CSI-RS antenna ports for each resource 2N g The configuration set corresponding to N1N2.

[0068] UE 115 may receive a CSI report configuration and may use the configuration to perform CSI reporting. For example, for a type I codebook, UE 115 may perform single slot reporting, and the CSI report may include two parts. The first part of the CSI report may include a rank indicator (RI), a CSI-RS resource indicator (CRI), a CQI for a first codeword, or some combination thereof. The second part of the CSI report may include a PMI, a CQI for a second codeword (e.g., if RI>4), or both. Such a CSI report may support periodic, semi-periodic, or aperiodic CSI (or any combination thereof) and may be sent via a short or long physical uplink control channel (PUCCH) and a physical uplink shared channel (PUSCH). For a type II codebook, the CSI report may also include two parts. The first part of the CSI report may include an RI, a CQI, an indication of the number of non-zero wideband amplitude coefficients for each layer, or some combination thereof. The first part of the CSI report may have a fixed payload size, and each field of the first part may be encoded separately. The first part of the CSI report may indicate the number of information bits included in the second part of the CSI report. The second part of the CSI report may include a PMI corresponding to a non-zero wideband amplitude coefficient for each layer indicated by the first part. Such a CSI report may support semi-periodic or aperiodic CSI and may be transmitted via a long PUCCH (e.g., the first part) and a PUSCH (e.g., the first part and the second part). The UE 115 may suppress the multiplexing of CSI parameters of the CSI report across PUCCH and PUSCH transmissions. The UE 115 may independently determine (e.g., generate, calculate) CSI reports on the long PUCCH and on the PUSCH. The UE capability may indicate whether the UE 115 supports a configuration with a type IICSI report on both the long PUCCH and the PUSCH. If the CSI report is transmitted via the long PUCCH or the PUSCH, the layer (L1) reference signal resource power (RSRP) and resource indicator for beam management may be mapped to the first part of the CSI report.

[0069] The wireless communication system 100 may additionally or alternatively use dynamic antenna port configuration adaptation at the network entity 105 to support network energy conservation. For example, to save energy, the network entity 105 may deactivate a certain number of antenna ports. Changing the number of active antenna ports used to communicate with the UE 115 may affect CSI reporting for the UE 115. For example, the UE 115 may be configured with one or more antenna port configurations for CSI reporting. In some examples, the UE 115 may be configured with multiple antenna port CQI configurations such that the UE 115 may be configured to report CQIs corresponding to 32 antenna ports (e.g., CSI-RS ports) and 16 antenna ports (e.g., CSI-RS ports). For example, the UE 115 may report sub-band CQI reports for the primary antenna port configuration and wideband CQI reports for other antenna port configurations (e.g., secondary antenna port configurations) to prioritize relatively finer CQI reports for the primary antenna port configuration while using relatively smaller granularity to inform the network of CQI for the secondary antenna port configuration (e.g., to save processing and signaling overhead). If the network entity 105 updates the antenna port configuration, the UE 115 may use the mapping to update the CSI reporting granularity. If the network entity 105 performs antenna port configuration adaptation, the mapping may support efficient CSI reporting (CQI reporting, PMI reporting) for different antenna port configurations.

[0070] Figure 2An example of a network architecture 200 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is illustrated. For example, the network architecture 200 may be a disaggregated base station architecture, a disaggregated RAN architecture, or some other architecture that supports multiple network entities 105. 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 that may communicate directly with a core network 130-a via a backhaul communication link 120-a, or indirectly with a core network 130-a through one or more disaggregated 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 corresponding midhaul communication link 162-a (e.g., an F1 interface). The DU 165-a may communicate with one or more RUs 170-a via respective fronthaul communication links 168-a. The RU 170-a may be associated with respective coverage areas 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.

[0071] Each of the network entities 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 send 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 an interface of the network entity 105 may be configured to communicate with one or more of the other network entities 105 via a transmission medium. For example, these network entities 105 may include a wired interface that is configured to receive signals on a wired transmission medium or send signals to one or more of the other network entities 105 on a 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 via a wireless transmission medium, or to send signals to one or more network entities in other network entities 105 via a wireless transmission medium, or both.

[0072] In some examples, CU 160-a may host one or more higher layer control functions. Such control functions may include RRC, PDCP, SDAP, or other control functions. Each control function may be implemented using an interface that is configured to communicate signals with other control functions hosted by CU 160-a. CU 160-a may be configured to manage user plane functionality (e.g., CU-UP), control plane functionality (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 unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). CU 160-a may be implemented to communicate with DU 165-a for network control and signaling.

[0073] 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, DU 165-a may at least partially host one or more of the RLC layer, the MAC layer, and one or more aspects of the PHY layer (e.g., a high PHY layer, such as modules for FEC encoding and decoding, scrambling, modulation and demodulation, or other functionality), depending at least in part on functional splits, such as those defined by the Third Generation Partnership Project (3GPP). In some examples, DU 165-a may also host one or more low PHY layers. Each layer may be implemented using an interface that is configured to communicate signals with other layers hosted by DU 165-a or with control functions hosted by CU 160-a.

[0074] In some examples, lower layer functionality may be implemented by one or more RUs 170-a. For example, a RU 170-a controlled by a 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 or other functionality) or both based at least in part on functional splitting (such as lower layer functional splitting). In this architecture, RU 170-a may be implemented to manage over-the-air (OTA) communications with one or more UEs 115-a. In some specific implementations, real-time and non-real-time aspects of control plane and user plane communications with RU 170-a may be controlled by corresponding DU 165-a. In some examples, this configuration may enable DU165-a and CU 160-a to be implemented in a cloud-based RAN architecture (such as a vRAN architecture).

[0075] SMO 180-a may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network entities 105. For non-virtualized network entities 105, SMO 180-a may be configured to support the deployment of dedicated physical resources for RAN coverage, which may be managed via an operation and maintenance interface (e.g., an O1 interface). For virtualized network entities 105, SMO 180-a may be configured to interact with a cloud computing platform (e.g., O-Cloud 205) to perform network entity lifecycle management (e.g., instantiate virtualized network entities 105) via a cloud computing platform interface (e.g., an O2 interface). Such virtualized network entities 105 may include, but are not limited to, CU 160-a, DU 165-a, RU 170-a, and near-RT RIC 175-b. In some specific implementations, SMO 180-a may communicate (e.g., via an O1 interface) with components configured according to a 4G RAN. Additionally or alternatively, in some implementations, the SMO 180-a may communicate directly with one or more RUs 170-a via an O1 interface. The SMO 180-a may also include a non-RT RIC 175-a configured to support the functionality of the SMO 180-a.

[0076] The non-RT RIC 175-a may 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 guidance of applications / features in the near-RT RIC 175-b. The non-RT RIC 175-a may be coupled to or communicate with the near-RT RIC 175-b (e.g., via an A1 interface). The near-RT RIC 175-b may be configured to include logic functions that implement near-real-time control and optimization of RAN elements and resources via data collection and actions through an interface connecting one or more CUs 160-a, one or more DUs 165-a, or both, and the O-eNB 210 to the near-RTTRIC 175-b (e.g., via an E2 interface).

[0077] In some examples, in order 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 from a non-network data source or from a network function at the SMO 180-a or the non-RT RIC 175-a. 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 ML model to perform corrective actions through the SMO 180-a (e.g., via reconfiguration of O1) or via the generation of a RAN management policy (such as an A1 policy).

[0078] The network architecture 200 may support mapping of subband sizes for CSI reporting to antenna port configurations. For example, a network entity 105 (such as RU 170-a) may include a set of antenna ports and may dynamically change the number of active antenna ports (e.g., for network power conservation). A UE 115-a in communication with the RU 170-a may receive an indication of a change to the active antenna port configuration and may determine a corresponding change to the subband size for CSI reporting based on the mapping. The network may determine the same mapping, for example, at the CU 160-a, DU 165-a, RU 170-a, or any combination thereof. By using the same mapping at the network side and at the UE 115-a, the network architecture 200 may support alignment between entities for CSI-RS transmission and CSI reporting.

[0079] Figure 3 An example of a wireless communication system 300 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is illustrated. The wireless communication system 300 may include a network entity 105-a and a UE 115-b, which may be a reference Figure 1 and Figure 2 Examples of the described apparatus. The network entity 105-a may be an example of a RU 170, a base station 140, or both that includes an antenna port set 315. The network entity 105-a may support dynamically updating the antenna port configuration of the antenna port set 315. To improve reporting accuracy and network flexibility, the network entity 105-a and the UE 115-b may support mapping from different antenna port configurations to different subband sizes for CSI reporting.

[0080] The network entity 105-a can use the antenna port set 315 to communicate with one or more UEs 115, other network entities 105, or both within the coverage area 110-b. In order to support large-scale MIMO communications, the network entity 105-a may include a relatively large number of antenna ports for concurrently communicating with multiple different wireless devices. For example, the antenna port set 315 may include multiple co-located panels, each panel including multiple antenna ports. The panel (e.g., antenna panel) may be equipped with a relatively large number of power amplifiers and antenna subsystems to support MIMO technology. However, the power amplifier, antenna subsystem, or both may consume power, resulting in a relatively high power overhead for the network. In order to support network power conservation, the network entity 105-a may dynamically deactivate one or more antenna panels, sub-panels, antenna ports, or any combination thereof to improve energy efficiency at the network. For example, if the cell load of network entity 105-a is relatively low (e.g., the number of devices communicating with network entity 105-a is below a threshold), network entity 105-a may deactivate antenna port groups in antenna port set 315 so that the remaining active antenna ports can maintain communication with devices within the cell coverage. For example, network entity 105-a may deactivate antenna port group 320-b, antenna port group 320-c, and antenna port group 320-d, and network entity 105-a may use active antenna port group 320-a to maintain communication. In some examples, antenna port group 320-a may correspond to an antenna panel.

[0081] The network entity 105-a may use DCI signaling to indicate dynamic antenna port adaptation (e.g., to support relatively low latency switching of antenna port configurations). For example, the network entity 105-a may send an antenna port configuration update 325 to the UE 115-b via the downlink channel 305 to indicate a change to the active antenna port configuration. In some examples, the antenna port configuration update 325 may indicate the number of antenna ports that are currently active after antenna port adaptation, the number of antenna ports that are deactivated after antenna port adaptation, an update to the primary antenna port configuration for the network entity 105-a after antenna port adaptation, or any combination thereof. The antenna port configuration update 325 may be indicated via DCI signaling (e.g., using a field in a DCI message).

[0082] However, in some examples, the network entity 105-a may not support dynamically adapting CSI reporting parameters, such as subband size for CSI reporting. For example, the network entity 105-a may configure CSI reporting parameters via RRC signaling, but may adapt antenna port configuration via DCI signaling.

[0083] To support similar dynamic updates of CSI reporting based on antenna port configuration updates 325, UE 115-b may store mappings 335 between different antenna port configurations and different subband sizes for CSI reporting. The subband size may span a certain number of resource blocks (RBs) or other frequency resources in the frequency domain. In response to antenna port configuration updates 325, UE 115-b may determine updated subband sizes for CSI reporting and may use the updated subband sizes (e.g., without receiving a CSI report reconfiguration message from network entity 105-a). Based on antenna port configuration updates 325, the updated subband sizes for CSI reporting may meet an accuracy threshold for CSI reporting. Mappings 335 may be between different numbers of antenna ports and different subband sizes for CSI reporting, between different types of antenna port configurations and different subband sizes for CSI reporting, or both. In some examples, mappings 335 may use scaling operations 340 to determine different mappings between antenna port configurations and subband sizes for CSI reporting. The network entity 105 - a may store the same mapping 335 and may send a set of reference signals 330 to the UE 115 - b based on the mapping 335 for CSI measurement.

[0084] In some examples, an original equipment manufacturer (OEM) of UE 115-b may configure UE 115-b with mapping 335. In some other examples, network entity 105-a may configure UE 115-b with mapping 335 via control signaling (e.g., RRC signaling, MAC-CE, DCI signaling). The control signaling may indicate mapping 335 (e.g., different antenna port configurations and corresponding subband size values) or may indicate a mapping index. If the control signaling indicates a mapping index, UE 115-b may store a set of options for mapping 335, and UE 115-b may determine the option to use based on the indicated mapping index. Network entity 105-a may additionally configure mapping options that may be configured at UE 115-b in other ways. Control of the subband size for each antenna port configuration by network entity 105-a (e.g., via RRC signaling) may provide robust flexibility for antenna port configuration and CSI report adaptation. In yet other examples, UE 115-b may determine mapping 335 and may send a request to network entity 105-a indicating the determined mapping 335. Network entity 105-a may approve or deny use of the determined mapping 335 for UE 115-b.

[0085] In some examples, mapping 335 may configure a corresponding subband size for CSI reporting by UE 115-b for each antenna port configuration in a set of antenna port configurations. In some examples, mapping 335 may configure separate mappings for PMI reporting and CQI reporting. For example, mapping 335 may map from an antenna port configuration (e.g., the number of active antenna ports) to a first subband size for PMI reporting and a second subband size for CQI reporting. In some implementations, the first subband size and the second subband size may be the same or different. Table 1 provides an example mapping 335 from different numbers of active antenna ports (e.g., different antenna port codebooks, different antenna port configurations) to different subband sizes for PMI reporting, CQI reporting, or both.

[0086] Antenna port configuration PMI subband size CQI subband size 32 ports 4 RBs 8 RBs 16 ports 8 RBs 8 RBs 8 ports 12 RBs 16 RBs 4 ports 16 RBs 16 RBs

[0087] Table 1: Example mapping

[0088] In some examples, network entity 105-a may configure UE 115-b to report subband-based CSI reports for a primary port configuration and to report wideband-based CSI reports for other port configurations (e.g., secondary port configurations). If UE 115-b stores a mapping 335 between the number of active antenna ports and subband sizes used for CSI reporting, UE 115-b may apply mapping 335 to the primary port configuration and may apply a different mapping to the secondary port configuration, or may use a default band size (e.g., a wideband value) for the secondary port configuration.

[0089] In some examples, mapping 335 may configure corresponding subband sizes for CSI reporting by UE 115-b for different types of antenna port configurations (e.g., primary antenna port configuration versus secondary antenna port configuration). The primary antenna port configuration may correspond to subband CSI reporting (e.g., spanning a first number of frequency resources), and the secondary antenna port configuration may correspond to wideband CSI reporting (e.g., spanning a second number of frequency resources greater than the first number). Such a mapping 335 may provide relatively greater granularity and, accordingly, relatively greater accuracy for the primary antenna port configuration as compared to the secondary antenna port configuration. Table 2 provides an example mapping 335 from different antenna port configuration types to different subband sizes for CSI reporting (e.g., PMI reporting, CQI reporting, or both).

[0090] Antenna port configuration type CSI subband size host 4 RBs auxiliary 12 RBs

[0091] Table 2: Example mapping

[0092] In some examples, mapping 335 may configure separate mappings for PMI reporting and CQI reporting. For example, mapping 335 may map from a primary antenna port configuration configured for UE 115-b to a first subband size for PMI reporting and a second subband size for CQI reporting. Additionally or alternatively, mapping 335 may map from a secondary antenna port configuration configured for UE 115-b to a third subband size for PMI reporting and a fourth subband size for CQI reporting, and UE 115-b may report CSI for one or more secondary port configurations. Based on mapping 335, the first subband size, the second subband size, the third subband size, and the fourth subband size may all be different, or may include one or more of the same values. Table 3 provides an example mapping 335 from different antenna port configuration types to different subband sizes for PMI reporting and CQI reporting.

[0093] Antenna port configuration type PMI subband size CQI subband size host 4 RBs 8 RBs auxiliary 16 RBs 16 RBs

[0094] Table 3: Example mapping

[0095] The primary antenna port configuration may correspond to a primary CSI reporting codebook, and the secondary antenna port configuration may correspond to a secondary CSI reporting codebook. For example, based on the configuration of UE 115-b, UE 115-b may report CSI measurements for one primary antenna port configuration and may report CSI measurements for any number of secondary antenna port configurations.

[0096] In some examples, the network entity 105-a may configure the UE 115-b with a subband size for a first number of antenna ports, and the UE 115-b may apply the scaling operation 340 to determine additional subband sizes corresponding to other numbers of antenna ports. For example, the network entity 105-a may configure the UE 115-b with a first subband size of 16 RBs for CSI reporting for 32 active antenna ports. Based on the scaling operation 340 (e.g., to maintain the same ratio of RBs to active antenna ports) and the first subband size configured for the first number of active antenna ports (e.g., 32), the UE 115-b may determine to use a subband size of 8 RBs for CSI reporting for the 16 active antenna ports. The UE 115-b may determine one or more additional mappings from the number of active antenna ports to subband sizes based on the scaling operation 340.

[0097] Scaling operation 340 may be an example of a fixed scaling operation configured at UE 115-b, or network entity 105-a may configure scaling operation 340 for UE 115-b (e.g., via RRC signaling). In some examples, scaling operation 340 may include, for example, linear scaling based on scaling parameter α. In some such examples, network entity 105-a may configure the scaling parameter via control signaling, and UE 115-b may determine mapping 335 based on the scaling parameter according to Equation 1.

[0098] Sub-Band Size=α×Quantity of Ports (1)

[0099] In some other examples, scaling operation 340 may include, for example, non-linear scaling based on an RRC configuration relationship or some other general scaling. In some examples, scaling operation 340 may be the same or different for PMI reports and CQI reports.

[0100] UE 115-b may receive an antenna port configuration update 325 from network entity 105-a (e.g., via DCI signaling, MAC-CE signaling), and may determine an update to the active antenna port configuration at network entity 105-a. For example, antenna port configuration update 325 may indicate an updated number of active antenna ports at network entity 105-a. Additionally or alternatively, antenna port configuration update 325 may indicate an updated primary antenna port configuration for network entity 105-a (e.g., indicating a switch to communicate using an antenna port configuration different from a “primary” antenna port configuration). Based on antenna port configuration update 325 and mapping 335 (e.g., mapping 335 previously configured at UE 115-b), UE 115-b may determine corresponding updates to one or more subband sizes for CSI reporting (e.g., PMI reporting, CQI reporting, or both).

[0101] The network entity 105-a may transmit a set of reference signals 330, such as CSI-RS, synchronization signal blocks (SSBs), or other reference signals, that support CSI measurements. The network entity 105-a may transmit the reference signals 330 with a granularity based on an updated subband size for CSI reporting. For example, if the updated subband size for CSI reporting is 4 RBs, the network entity 105-a may transmit CSI-RS at least every 4 RBs within the frequency range used for CSI reporting. The UE 115-b may monitor and detect one or more reference signals 330 in the set of reference signals 330. The UE 115-b may perform CSI measurements using the detected reference signals 330 to determine CSI for a channel between the UE 115-b and the network entity 105-a. Additionally or alternatively, the UE 115 - b may perform CSI measurements on one or more other network entities 105 using reference signals 330 received from the other network entities 105 and using the determined subband size for CSI reporting.

[0102] UE 115-b may send a CSI report 345 to network entity 105-a via uplink channel 310 based on the CSI measurement. For example, the granularity of the CSI measurement in the CSI report 345 may be based on the subband size for CSI reporting determined according to antenna port configuration update 325. For example, if UE 115-b determines that the subband size for CSI reporting is 4 RBs, UE 115-b may include CSI measurements corresponding to the corresponding 4RB subbands in the CSI report 345. In some examples, UE 115-b may use different reporting granularities in the CSI report 345 for primary antenna port configuration versus secondary antenna port configuration, PMI reporting versus CQI reporting, or both. Network entity 105-a may receive the CSI report 345 and may determine CSI measurements for UE 115-b based on information in the CSI report 345.

[0103] By using the mapping 335, the UE 115-b may dynamically update the subband size used for CSI reporting (e.g., PMI reporting, CQI reporting, or both) for different antenna port configurations, e.g., in response to an antenna port configuration update 325 triggered by the network entity 105-a. If the network entity 105-a dynamically adapts the active antenna port configuration (e.g., which antenna ports in the antenna port set 315 are currently active), such dynamic updates may support improved CSI reporting. For example, if the network entity 105-a reduces the number of active antenna ports, the mapping 335 may allow the UE 115-b to increase the subband size used for CSI reporting accordingly, thereby reducing the processing overhead and signaling overhead associated with CSI reporting. Additionally or alternatively, if the network entity 105-a increases the number of active antenna ports, mapping 335 may allow UE 115-b to correspondingly reduce the subband size used for CSI reporting, thereby supporting relatively finer CSI feedback and correspondingly supporting relatively more accurate precoding for communication between UE 115-b and the network entity 105-a.

[0104] Figure 4 An example of a process flow 400 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is illustrated. The process flow 400 may be used in reference to Figures 1 to 3 The process flow 400 may include a UE 115-c (which may be a wireless communication system 100, network architecture 200, or wireless communication system 300). Figures 1 to 3 115) and the network entity 105-b (which may be as described in reference Figures 1 to 3 105-b). The process flow 400 may support mapping between different antenna port configurations and corresponding subband sizes for CSI reporting, thereby allowing the UE 115-c to update the CSI reporting granularity in response to dynamic antenna port configuration adaptation at the network entity 105-b. In the following description of the process flow 400, the operations performed by the device may be performed in a different order or at different times. Additionally or alternatively, some operations may be omitted from the process flow 400 and other operations may be added to the process flow 400.

[0105] In some examples, at 405, the network entity 105-b may send a control signal to configure a subband size mapping for the UE 115-c. The control signal may be an example of an RRC signal. In some other examples, the UE 115-c may be pre-configured with a mapping (e.g., by an OEM or otherwise). The mapping may map between different antenna port configurations and corresponding subband sizes for CSI reporting. The mapping may provide an association between an updated antenna port configuration and a subband size for reporting CSI.

[0106] In some examples, the control signal may configure a mapping from the number of antenna ports to the corresponding subband size. The control signal may configure a first mapping from the number of antenna ports to a first corresponding subband size for PMI reporting, a second mapping from the number of antenna ports to a second corresponding subband size for CQI reporting, or both. In some other examples, the control signal may configure a mapping from an antenna port configuration type to a corresponding subband size. For example, UE 115-c may be configured with multiple antenna port configurations for network entity 105-b, the multiple antenna port configurations including a primary antenna port configuration and one or more secondary antenna port configurations. The control signal may configure a mapping from the primary antenna port configuration to a primary subband size for CSI reporting and from one or more secondary antenna port configurations to a secondary subband size for CSI reporting. For example, the control signal may configure a first mapping from the primary antenna port configuration to a first primary subband size for PMI reporting and from one or more secondary antenna port configurations to a first secondary subband size for PMI reporting. Additionally or alternatively, the control signal may configure a second mapping from the primary antenna port configuration to a second primary subband size for CQI reporting and from one or more secondary antenna port configurations to a second secondary subband size for CQI reporting.

[0107] In yet other examples, the control signal may configure a first mapping from a first number of antenna ports to a corresponding subband size for CSI reporting. In some such examples, at 410, the UE 115-c may perform a scaling operation to determine other mappings. For example, the UE 115-c may determine additional mappings from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes for CSI reporting based on the first mapping and the scaling operation. In some examples, the scaling operation may be pre-configured at the UE 115-c. In some other examples, the scaling operation may be configured by the network entity 105-b (e.g., via RRC signaling). The scaling operation may be a linear scaling operation or a non-linear scaling operation. In some examples, the UE 115-c may use different scaling operations for PMI mapping and CQI mapping, may use different first mappings configured by the network for PMI mapping and CQI mapping, or both.

[0108] At 415, the network entity 105-b may update the antenna port configuration. For example, the network entity 105-b may perform dynamic antenna port configuration adaptation to adjust network power savings associated with antenna port usage (e.g., based on active power amplifiers, antenna subsystems, or both). The network entity 105-b may update the number of active antenna ports for the network entity 105-b from the first number of antenna ports to the second number of antenna ports. Additionally or alternatively, the network entity 105-b may update the primary antenna port configuration for the network entity 105-b from the first antenna port configuration to the second antenna port configuration.

[0109] At 420, the network entity 105-b may send a control signal indicating an updated antenna port configuration for the network entity 105-b. The UE 115-c may receive the control signal and determine the updated antenna port configuration based on the control signal. The control signal may be an example of a DCI signal, a MAC-CE, or both. In some examples, the control signal may indicate an updated number of active antenna ports for the network entity 105-b, an antenna port configuration set to an updated primary antenna port configuration, or both. The UE 115-c may use the updated antenna port configuration and mapping (e.g., an association between the updated antenna port configuration and the subband size) to determine an updated subband size for CSI reporting. In some examples, the UE 115-c may determine multiple subband sizes for CSI reporting, such as different subband sizes for PMI reporting and CQI reporting, different subband sizes for primary antenna port configuration reporting and secondary antenna port configuration reporting, or some combination thereof.

[0110] At 425, the network entity 105-b may send a set of reference signals (e.g., CSI-RS, SSB) based on the updated antenna port configuration. The set of reference signals may support CSI reporting based on an association between the updated antenna port configuration and one or more subband sizes for CSI reporting. For example, the network entity 105-b may additionally store a mapping and determine an updated subband size for CSI reporting based on the updated antenna port configuration. The reference signal may support an updated subband size for CSI reporting at the UE 115-c. The UE 115-c may receive the reference signal set or at least a portion of the reference signal, and at 430, may perform CSI measurements using the reference signal. The UE 115-c may perform CSI measurements based on the CSI reporting granularity determined using the mapping. For example, the UE 115-c may determine CSI measurements (e.g., CQI values, PMI values) for multiple subbands based on the determined subband sizes.

[0111] At 435, the UE 115-c may send a CSI report including CSI measurements to the network entity 105-b based on the determined subband size and based on the reference signal. For example, based on the updated antenna port configuration, the CSI report may include corresponding CQI values ​​for multiple subbands of the CQI subband size for the CSI report. Additionally or alternatively, based on the updated antenna port configuration, the CSI report may include corresponding PMI values ​​for multiple subbands of the PMI subband size for the CSI report. In some examples, based on different subband granularities for the CSI report, the CSI report may include CSI measurements for a primary antenna port configuration and one or more secondary antenna port configurations. The UE 115-c and the network entity 105-b may communicate based on the CSI measurements included in the CSI report.

[0112] Figure 5 A block diagram of a device 505 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The device 505 can be an example of aspects of a UE 115. The device 505 may include a receiver 510, a transmitter 515, and a communication manager 520. The communication manager 520 may be implemented at least in part by one or both of a modem and a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0113] The receiver 510 may provide means 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 determining subband sizes for CSI reporting based on antenna port configuration adaptation). The information may be passed to other components of the device 505. The receiver 510 may utilize a single antenna or a collection of multiple antennas.

[0114] The transmitter 515 may provide means for transmitting signals generated by other components of the device 505. For example, the transmitter 515 may transmit information associated with various information channels (e.g., control channels, data channels, information channels related to determining subband sizes for CSI reporting based on antenna port configuration adaptation), such as packets, user data, control information, or any combination thereof. In some examples, the transmitter 515 may be co-located with the receiver 510 in a transceiver module. The transmitter 515 may utilize a single antenna or a collection of multiple antennas.

[0115] The communication manager 520, the receiver 510, the transmitter 515, or various combinations thereof, or various components thereof may be examples of means for performing various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 520, the receiver 510, the transmitter 515, or various combinations thereof, or components thereof may support methods for performing one or more of the functions associated with determining a subband size for CSI reporting.

[0116] In some examples, communication manager 520 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with receiver 510, transmitter 515, or both. For example, communication manager 520 may receive information from receiver 510, transmit information to transmitter 515, or be integrated in conjunction with receiver 510, transmitter 515, or both to obtain information, output information, or perform various other operations associated with subband size determination for CSI reporting.

[0117] According to examples as disclosed herein, the communication manager 520 may support wireless communications at a UE. For example, the communication manager 520 may be configured to or otherwise support components for receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The communication manager 520 may be configured to or otherwise support components for receiving a set of multiple reference signals from the network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The communication manager 520 may be configured to or otherwise support components for sending a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0118] By including or configuring the communication manager 520, the device 505 (e.g., a processor that controls or is otherwise coupled to the receiver 510, the transmitter 515, the communication manager 520, or a combination thereof) may support techniques for reducing latency and processing overhead associated with reconfiguring CSI reporting granularity. For example, the device 505 may update the CSI reporting granularity using an association between the updated antenna port configuration and the subband size for reporting CSI in response to an updated antenna port configuration, rather than using RRC signaling to reconfigure the subband size for CSI reporting. Additionally or alternatively, the device 505 may use techniques associated with determining the subband size for CSI reporting to improve CSI measurement accuracy, thereby improving communication reliability and correspondingly reducing processing resources involved in retransmissions. Based on determining the CSI reporting granularity using a mapping, the device 505 may reduce the number of processing units initiated to manage CSI report reconfiguration signaling, retransmission signaling, or both.

[0119] Figure 6 A block diagram of a device 605 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The device 605 can be an example of aspects of the device 505 or the UE 115. The device 605 may include a receiver 610, a transmitter 615, and a communication manager 620. The communication manager 620 may be implemented at least in part by one or both of a modem and a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0120] The receiver 610 may provide means 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 determining subband sizes for CSI reporting based on antenna port configuration adaptation). 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.

[0121] The transmitter 615 may provide means for transmitting signals generated by other components of the device 605. For example, the transmitter 615 may transmit information associated with various information channels (e.g., control channels, data channels, information channels related to determining subband sizes for CSI reporting based on antenna port configuration adaptation), such as packets, user data, control information, or any combination thereof. In some examples, the transmitter 615 may be co-located with the receiver 610 in a transceiver module. The transmitter 615 may utilize a single antenna or a collection of multiple antennas.

[0122] The device 605 or its various components may be examples of means for performing various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 620 may include an antenna port configuration update component 625, a reference signal measurement component 630, a CSI reporting component 635, or any combination thereof. In some examples, the communication manager 620 or its various components may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the receiver 610, the transmitter 615, or both. For example, the communication manager 620 may receive information from the receiver 610, transmit information to the transmitter 615, or be integrated in combination with the receiver 610, the transmitter 615, or both to obtain information, output information, or perform various other operations associated with determining a subband size for CSI reporting.

[0123] According to examples as disclosed herein, the communication manager 620 may support wireless communications at a UE. The antenna port configuration update component 625 may be configured to or otherwise support means for receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The reference signal measurement component 630 may be configured to or otherwise support means for receiving a set of multiple reference signals from a network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The CSI reporting component 635 may be configured to or otherwise support means for sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0124] Figure 7 A block diagram of a communication manager 720 that supports determining a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is shown. The communication manager 720 or its various components may be examples of components for performing various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 720 may include an antenna port configuration update component 725, a reference signal measurement component 730, a CSI reporting component 735, a subband size mapping component 740, a scaling component 745, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses).

[0125] According to examples as disclosed herein, the communication manager 720 may support wireless communications at a UE. The antenna port configuration update component 725 may be configured to or otherwise support means for receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The reference signal measurement component 730 may be configured to or otherwise support means for receiving a set of multiple reference signals from a network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The CSI reporting component 735 may be configured to or otherwise support means for sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0126] In some examples, subband size mapping component 740 can be configured to or otherwise support means for receiving a second control signal from a network entity that configures a mapping from a set of multiple numbers of antenna ports to a set of multiple corresponding subband sizes. The updated association between the antenna port configuration and the subband size can be based on the mapping.

[0127] In some examples, the second control signal configures a first mapping from a set of multiple antenna port numbers to a first set of multiple corresponding subband sizes for PMI reporting, a second mapping from a set of multiple antenna port numbers to a second set of multiple corresponding subband sizes for CQI reporting, or both. In some examples, the CSI report includes PMI information according to the first set of multiple corresponding subband sizes, CQI information according to the second set of multiple corresponding subband sizes, or both. In some examples, the second control signal includes an RRC signal.

[0128] In some examples, the UE is configured with a set of multiple antenna port configurations for a network entity, the set of multiple antenna port configurations including a primary antenna port configuration and one or more secondary antenna port configurations, and the subband size mapping component 740 can be configured to or otherwise support means for receiving a second control signal from the network entity, the second control signal configuring a mapping from the primary antenna port configuration to the primary subband size and from the one or more secondary antenna port configurations to the secondary subband size. The updated association between the antenna port configuration and the subband size can be based on the mapping.

[0129] In some examples, the second control signal configures a first mapping from a primary antenna port configuration to a first primary subband size for PMI reporting and from one or more secondary antenna ports configuration to a first secondary subband size for PMI reporting, a second mapping from the primary antenna port configuration to a second primary subband size for CQI reporting and from one or more secondary antenna ports configuration to a second secondary subband size for CQI reporting, or both. In some examples, the CSI report includes PMI information according to the first primary subband size and the first secondary subband size, CQI information according to the second primary subband size and the second secondary subband size, or both. In some examples, the second control signal includes an RRC signal.

[0130] In some examples, the updated antenna port configuration indicates an updated number of active antenna ports for the network entity, an updated primary antenna port configuration for the network entity, or both.

[0131] In some examples, the subband size mapping component 740 may be configured to or otherwise support a component for receiving a second control signal from a network entity that configures a first mapping from a number of antenna ports to a corresponding subband size. In some examples, the scaling component 745 may be configured to or otherwise support a component for determining an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes based on the first mapping and the scaling operation. The association between the updated antenna port configuration and the subband size can be based on the first mapping, the additional mapping, or both. In some examples, the second control signal further configures the scaling operation.

[0132] In some examples, the control signal includes a DCI signal, a MAC-CE, or both.

[0133] Figure 8 A diagram of a system including a device 805 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The device 805 may be an example of a device 505, a device 605, or a UE 115 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 communications, including components for sending 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, a code 835, and a processor 840. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 845).

[0134] I / O controller 810 can manage input signals and output signals of device 805. I / O controller 810 can also manage peripheral devices that are not integrated into device 805. In some implementations, I / O controller 810 can represent a physical connection or port to an external peripheral device. In some implementations, I / O controller 810 can utilize an operating system, such as or another known operating system. Additionally or alternatively, the I / O controller 810 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some implementations, the I / O controller 810 may be implemented as part of a processor, such as the processor 840. In some implementations, 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.

[0135] In some implementations, the device 805 may include a single antenna 825. However, in some other implementations, the device 805 may have more than one antenna 825, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 815 may communicate bidirectionally via one or more antennas 825, a wired or wireless link. For example, the transceiver 815 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The 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. The transceiver 815 or the transceiver 815 and the one or more antennas 825 may be examples of the transmitter 515, the transmitter 615, the receiver 510, the receiver 610, or any combination thereof or components thereof.

[0136] The memory 830 may include random access memory (RAM) and read-only memory (ROM). The memory 830 may store computer-readable, computer-executable code 835 including instructions that, when executed by the processor 840, cause the device 805 to perform various functions associated with subband size determination for CSI reporting. The code 835 may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. In some implementations, the code 835 may not be directly executable by the processor 840, but may (e.g., when compiled and executed) cause a computer to perform functions associated with subband size determination for CSI reporting. In some implementations, the memory 830 may include, among other things, a basic I / O system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0137] The processor 840 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some specific implementations, the processor 840 may be configured to operate a memory array using a memory controller. In some other specific implementations, the memory controller may be integrated into the processor 840. The processor 840 may be configured to execute computer-readable instructions stored in a memory (e.g., a memory 830) to cause the device 805 to perform various functions (e.g., functions or tasks that support determining a subband size for CSI reporting based on antenna port configuration adaptation). For example, the device 805 or a component of the device 805 may include a processor 840 and a memory 830 coupled to or coupled to the processor 840, and the processor 840 and the memory 830 are configured to perform various functions associated with determining a subband size for CSI reporting.

[0138] According to examples as disclosed herein, the communication manager 820 may support wireless communications at a UE. For example, the communication manager 820 may be configured to or otherwise support a component for receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The communication manager 820 may be configured to or otherwise support a component for receiving a set of multiple reference signals from the network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The communication manager 820 may be configured to or otherwise support a component for sending a CSI report including a CSI measurement to the network entity, the CSI measurement being based on the subband size and the set of multiple reference signals.

[0139] By including or configuring the communication manager 820, the device 805 may support techniques for improving communication reliability, reducing latency associated with updating CSI reporting granularity, reducing power consumption, or any combination thereof.

[0140] In some examples, the communication manager 820 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with the transceiver 815, one or more antennas 825, or any combination thereof. 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 are executable by the processor 840 to cause the device 805 to perform various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation, or the processor 840 and the memory 830 may be otherwise configured to perform or support such operations.

[0141] Fig. 9 A block diagram of a device 905 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The device 905 may be an example of aspects of a network entity 105 (such as a base station, RU, or some other network entity). The device 905 may include a receiver 910, a transmitter 915, and a communication manager 920. The communication manager 920 may be implemented at least in part by one or both of a modem and a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0142] The receiver 910 may provide means 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 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) interfaces, wireless interfaces, or any combination thereof.

[0143] The transmitter 915 may provide a means for outputting (e.g., sending, providing, conveying, transmitting) information generated by other components of the device 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 sending signals via one or more antennas. Additionally or alternatively, the transmitter 915 may support outputting information by sending signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 915 and the receiver 910 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0144] The communication manager 920, the receiver 910, the transmitter 915, or various combinations thereof, or various components thereof may be examples of means for performing various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 920, the receiver 910, the transmitter 915, or various combinations thereof, or components thereof may support methods for performing one or more of the functions associated with determining a subband size for CSI reporting.

[0145] In some examples, communication manager 920 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with receiver 910, transmitter 915, or both. For example, communication manager 920 may receive information from receiver 910, transmit information to transmitter 915, or be integrated in conjunction with receiver 910, transmitter 915, or both to obtain information, output information, or perform various other operations associated with subband size determination for CSI reporting.

[0146] According to examples as disclosed herein, the communication manager 920 may support wireless communications at a network entity. For example, the communication manager 920 may be configured to or otherwise support components for sending a control signal indicating an updated antenna port configuration for the network entity. The communication manager 920 may be configured to or otherwise support components for sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The communication manager 920 may be configured to or otherwise support components for receiving a CSI report including a CSI measurement based on the subband size and the set of multiple reference signals.

[0147] By including or configuring the communication manager 920, the device 905 (e.g., a processor controlling or otherwise coupled to the receiver 910, the transmitter 915, the communication manager 920, or a combination thereof) can support techniques for reducing power consumption while maintaining CSI report reliability. For example, the device 905 can dynamically update the antenna port configuration to reduce network power overhead. Additionally, the device 905 can reduce the signaling overhead associated with using mapping to adjust the CSI report granularity.

[0148] Fig.10 A block diagram of a device 1005 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The device 1005 may be an example of aspects of the device 905 or the network entity 105. The device 1005 may include a receiver 1010, a transmitter 1015, and a communication manager 1020. The communication manager 1020 may be implemented at least in part by one or both of a modem and a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0149] Receiver 1010 may provide means 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 device 1005. In some examples, receiver 1010 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, receiver 1010 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof.

[0150] The transmitter 1015 may provide a means for outputting (e.g., sending, providing, conveying, transmitting) 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 sending signals via one or more antennas. Additionally or alternatively, the transmitter 1015 may support outputting information by sending signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 1015 and the receiver 1010 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0151] The device 1005 or its various components may be examples of means for performing various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 1020 may include an antenna port configuration update component 1025, a reference signal transmission component 1030, a CSI reporting component 1035, or any combination thereof. In some examples, the communication manager 1020 or its various components may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the receiver 1010, the transmitter 1015, or both. For example, the communication manager 1020 may receive information from the receiver 1010, transmit information to the transmitter 1015, or be integrated in combination with the receiver 1010, the transmitter 1015, or both to obtain information, output information, or perform various other operations associated with determining a subband size for CSI reporting.

[0152] According to examples as disclosed herein, the communication manager 1020 can support wireless communications at a network entity. The antenna port configuration updating component 1025 can be configured to or otherwise support means for sending a control signal indicating an updated antenna port configuration for the network entity. The reference signal sending component 1030 can be configured to or otherwise support means for sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The CSI reporting component 1035 can be configured to or otherwise support means for receiving a CSI report including a CSI measurement based on the subband size and the set of multiple reference signals.

[0153] Fig.11A block diagram of a communication manager 1120 that supports determining a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The communication manager 1120 or its various components may be examples of components for performing various aspects of subband size for CSI reporting based on antenna port configuration adaptation. For example, the communication manager 1120 may include an antenna port configuration update component 1125, a reference signal transmission component 1130, a CSI reporting component 1135, a subband size mapping component 1140, an antenna port activation component 1145, a primary antenna port configuration component 1150, a scaling component 1155, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses), which communication may include communication within a protocol layer of a protocol stack, communication associated with a logical channel of a protocol stack (e.g., between protocol layers of a 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.

[0154] According to examples as disclosed herein, the communication manager 1120 may support wireless communications at a network entity. The antenna port configuration updating component 1125 may be configured to or otherwise support means for sending a control signal indicating an updated antenna port configuration for the network entity. The reference signal sending component 1130 may be configured to or otherwise support means for sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The CSI reporting component 1135 may be configured to or otherwise support means for receiving a CSI report including a CSI measurement based on the subband size and the set of multiple reference signals.

[0155] In some examples, subband size mapping component 1140 can be configured to or otherwise support means for sending a second control signal that configures a mapping from a set of multiple numbers of antenna ports to a set of multiple corresponding subband sizes. The updated association between the antenna port configuration and the subband size can be based on the mapping.

[0156] In some examples, the second control signal configures a first mapping from a set of multiple antenna port numbers to a first set of multiple corresponding subband sizes for PMI reporting, a second mapping from a set of multiple antenna port numbers to a second set of multiple corresponding subband sizes for CQI reporting, or both. In some examples, the CSI report includes PMI information according to the first set of multiple corresponding subband sizes, CQI information according to the second set of multiple corresponding subband sizes, or both. In some examples, the second control signal includes an RRC signal.

[0157] In some examples, the network entity is configured with a set of multiple antenna port configurations, the set of multiple antenna port configurations including a primary antenna port configuration and one or more secondary antenna port configurations, and the subband size mapping component 1140 can be configured to or otherwise support means for sending a second control signal that configures a mapping from the primary antenna port configuration to the primary subband size and from the one or more secondary antenna port configurations to the secondary subband size. The updated association between the antenna port configuration and the subband size can be based on the mapping.

[0158] In some examples, the second control signal configures a first mapping from a primary antenna port configuration to a first primary subband size for PMI reporting and from one or more secondary antenna ports configuration to a first secondary subband size for PMI reporting, a second mapping from the primary antenna port configuration to a second primary subband size for CQI reporting and from one or more secondary antenna ports configuration to a second secondary subband size for CQI reporting, or both. In some examples, the CSI report includes PMI information according to the first primary subband size and the first secondary subband size, CQI information according to the second primary subband size and the second secondary subband size, or both. In some examples, the second control signal includes an RRC signal.

[0159] In some examples, antenna port activation component 1145 can be configured or otherwise support means for updating the number of active antenna ports for a network entity from a first number of antenna ports to a second number of antenna ports. The updated antenna port configuration can indicate the second number of antenna ports.

[0160] In some examples, primary antenna port configuration component 1150 can be configured to or otherwise support means for updating a primary antenna port configuration for a network entity from a first antenna port configuration to a second antenna port configuration. The updated antenna port configuration can indicate the second antenna port configuration.

[0161] In some examples, the subband size mapping component 1140 may be configured to or otherwise support a component for sending a second control signal that configures a first mapping from the number of antenna ports to the corresponding subband size. In some examples, the scaling component 1155 may be configured to or otherwise support a component for determining an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes based on the first mapping and the scaling operation. The association between the updated antenna port configuration and the subband size can be based on the first mapping, the additional mapping, or both. In some examples, the second control signal further configures the scaling operation.

[0162] In some examples, the control signal includes a DCI signal, a MAC-CE, or both.

[0163] Fig.12 A diagram of a system including a device 1205 that supports determining a subband size for CSI reporting based on an active antenna port configuration in accordance with one or more aspects of the present disclosure is shown. The device 1205 may be an example of the device 905, the device 1005, or a network entity 105, or include components thereof. The device 1205 may communicate with one or more network entities 105, one or more UEs 115, or any combination thereof, which communication may include communication through one or more wired interfaces, through one or more wireless interfaces, or any combination thereof. The device 1205 may include components that support output and acquisition of communications, such as a communication manager 1220, a transceiver 1210, an antenna 1215, a memory 1225, a code 1230, and a processor 1235. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1240).

[0164] The transceiver 1210 may support bidirectional communication via a wired link, a wireless link, or both. 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 examples, 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 sending or output operations, or a combination thereof. In some examples, 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 examples, 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).

[0165] 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 various functions associated with subband size determination for CSI reporting. The code 1230 may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. In some implementations, the code 1230 may not be directly executable by the processor 1235, but may (e.g., when compiled and executed) cause a computer to perform functions associated with subband size determination for CSI reporting. In some implementations, the memory 1225 may include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0166] The processor 1235 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, a microcontroller, a programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or any combination thereof). In some specific implementations, the processor 1235 may be configured to operate a memory array using a memory controller. In some other specific implementations, 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., a memory 1225) to cause the device 1205 to perform various functions (e.g., functions or tasks that support determining a subband size for CSI reporting based on antenna port configuration adaptation). For example, the device 1205 or a component of the device 1205 may include a processor 1235 and a memory 1225 coupled to the processor 1235, and the processor 1235 and the memory 1225 are configured to perform various functions associated with determining a subband size for CSI reporting. 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)) that can host functionality (e.g., by executing code 1230) to perform the functions of device 1205. Processor 1235 may be any one or more suitable processors capable of executing scripts or instructions of one or more software programs stored in device 1205 (such as within memory 1225). In some examples, processor 1235 may be a component of a processing system. A processing system may generally refer to a system or series of machines or components that receive inputs and process those inputs to produce a set of outputs (which may be passed to, for example, other systems or components of device 1205). For example, a processing system of device 1205 may refer to a system that includes various other components or subcomponents of device 1205 (such as processor 1235, or transceiver 1210, or communication manager 1220, or other components or combinations of components of device 1205). The processing system of device 1205 can be docked with other components of device 1205, and can process information (such as input or signal) received from other components, or output information to other components. For example, a chip or modem of 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, as well as other specific implementations. In some examples, one or more interfaces may refer to an interface between a processing system of a chip or modem and a transmitter, so that device 1205 can send information output from the chip or modem.Additionally or alternatively, one or more interfaces may refer to an interface between a processing system of a chip or modem and a receiver, such that the 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 a first interface may also obtain information or signal input, and a second interface may also output information or signal output.

[0167] In some examples, bus 1240 may support communications of protocol layers (e.g., within protocol layers) of a protocol stack. In some examples, bus 1240 may support communications associated with logical channels of a protocol stack (e.g., between protocol layers of a protocol stack), which may include communications performed within components of device 1205, or communications performed between different components of device 1205 that may be co-located or located in different locations (e.g., and 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 of the different components or divided between the different components).

[0168] In some examples, the communication manager 1220 can manage aspects of communications with the core network 130 (e.g., via one or more wired or wireless backhaul links). For example, the communication manager 1220 can manage the transfer of data communications for client devices (such as one or more UEs 115). In some examples, the communication manager 1220 can manage communications with other network entities 105 and can include a controller or scheduler for controlling communications with the UE 115 in coordination with the other network entities 105. In some examples, the communication manager 1220 can support an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between network entities 105.

[0169] According to examples as disclosed herein, the communication manager 1220 may support wireless communications at a network entity. For example, the communication manager 1220 may be configured to or otherwise support components for sending a control signal indicating an updated antenna port configuration for the network entity. The communication manager 1220 may be configured to or otherwise support components for sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The communication manager 1220 may be configured to or otherwise support components for receiving a CSI report including a CSI measurement based on the subband size and the set of multiple reference signals.

[0170] By including or configuring the communication manager 1220 , the device 1205 may support techniques for improving communication reliability, reducing latency associated with updating CSI reporting granularity, reducing power consumption, or any combination thereof.

[0171] In some examples, the communication manager 1220 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the transceiver 1210, one or more antennas 1215 (e.g., if applicable), or any combination thereof. Although the communication manager 1220 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 1220 may be supported or performed by the transceiver 1210, the processor 1235, the memory 1225, the code 1230, or any combination thereof. For example, the code 1230 may include instructions that are executable by the processor 1235 to cause the device 1205 to perform various aspects of determining a subband size for CSI reporting based on antenna port configuration adaptation, or the processor 1235 and the memory 1225 may be otherwise configured to perform or support such operations.

[0172] Fig.13 A flowchart illustrating a method 1300 for supporting determination of a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The operations of the method 1300 may be implemented by a UE or a component thereof. For example, the operations of the method 1300 may be implemented by a UE as described in reference to Figures 1 to 8 The described UE 115 may be performed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0173] At 1305, the method may include receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The operations of 1305 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1305 may be performed as described in reference to Figure 7 The antenna port configuration update component 725 described above is performed.

[0174] At 1310, the method may include receiving a set of multiple reference signals from a network entity based on an updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The operations of 1310 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1310 may be performed by Figure 7 The described reference signal measurement component 730 is performed.

[0175] At 1315, the method may include sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on a subband size and a set of multiple reference signals. The operations of 1315 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1315 may be performed by Figure 7 The described CSI reporting component 735 is performed.

[0176] Fig.14 A flowchart illustrating a method 1400 for supporting determination of a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The operations of the method 1400 may be implemented by a UE or a component thereof. For example, the operations of the method 1400 may be implemented by a UE as described in reference to Figures 1 to 8 The described UE 115 may be performed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0177] At 1405, the method may include receiving a control signal from a network entity that configures a mapping from a set of multiple numbers of antenna ports to a set of multiple corresponding subband sizes. The operations of 1405 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1405 may be performed as described in reference to Figure 7 The described sub-band size mapping component 740 is performed.

[0178] At 1410, the method may include receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The operations of 1410 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1410 may be performed as described in reference to Figure 7 The antenna port configuration update component 725 described above is performed.

[0179] At 1415, the method may include receiving a set of multiple reference signals from a network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The association between the updated antenna port configuration and the subband size may be based on the mapping. The operations of 1415 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1415 may be performed by as described in reference Figure 7 The described reference signal measurement component 730 is performed.

[0180] At 1420, the method may include sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on a subband size and a set of multiple reference signals. The operations of 1420 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1420 may be performed by Figure 7 The described CSI reporting component 735 is performed.

[0181] Fig.15 A flowchart illustrating a method 1500 for supporting determination of a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by a UE or a component thereof. For example, the operations of the method 1500 may be implemented by a UE as described in reference to Figures 1 to 8 The described UE 115 may be performed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0182] At 1505, the method may include receiving a control signal from a network entity that configures a mapping from a primary antenna port configuration to a primary subband size and from one or more secondary antenna port configurations to secondary subband sizes. The operations of 1505 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1505 may be performed as described in reference to Figure 7 The described sub-band size mapping component 740 is performed.

[0183] At 1510, the method may include receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The operations of 1510 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed as described in reference to Figure 7 The antenna port configuration update component 725 described above is performed.

[0184] At 1515, the method may include receiving a set of multiple reference signals from a network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The association between the updated antenna port configuration and the subband size may be based on the mapping. The operations of 1515 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1515 may be performed by as described in reference Figure 7 The described reference signal measurement component 730 is performed.

[0185] At 1520, the method may include sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on a subband size and a set of multiple reference signals. The operations of 1520 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1520 may be performed by Figure 7 The described CSI reporting component 735 is performed.

[0186] Fig.16 A flowchart illustrating a method 1600 for supporting determination of a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The operations of the method 1600 may be implemented by a UE or a component thereof. For example, the operations of the method 1600 may be implemented by a UE as described in reference to Figures 1 to 8 The described UE 115 may be performed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0187] At 1605, the method may include receiving a control signal from a network entity that configures a first mapping from a number of antenna ports to corresponding subband sizes. The operations of 1605 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed as described in reference to Figure 7 The described sub-band size mapping component 740 is performed.

[0188] At 1610, the method may include determining, based on the first mapping and scaling operation, an additional mapping from one or more additional antenna port quantities to one or more additional corresponding subband sizes. The operations of 1610 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1610 may be performed as described in reference to Figure 7 The described scaling component 745 is performed.

[0189] At 1615, the method may include receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity. The operations of 1615 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1615 may be performed as described in reference to Figure 7 The antenna port configuration update component 725 described above is performed.

[0190] At 1620, the method may include receiving a set of multiple reference signals from a network entity based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for reporting CSI. The association between the updated antenna port configuration and the subband size may be based on the first mapping, the additional mapping, or both. The operations of 1620 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1620 may be performed by as described in reference Figure 7 The described reference signal measurement component 730 is performed.

[0191] At 1625, the method may include sending a CSI report including a CSI measurement to a network entity, the CSI measurement being based on a subband size and a set of multiple reference signals. The operations of 1625 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1625 may be performed by Figure 7 The described CSI reporting component 735 is performed.

[0192] Fig.17 A flowchart illustrating a method 1700 for supporting determination of a subband size for CSI reporting based on an active antenna port configuration according to one or more aspects of the present disclosure is shown. The operations of the method 1700 may be implemented by a network entity or a component thereof. For example, the operations of the method 1700 may be implemented by a network entity or a component thereof. Figures 1 to 4 and Figures 9 to 12 In some examples, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0193] At 1705, the method may include sending a control signal indicating an updated antenna port configuration for the network entity. The operations of 1705 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed as described in reference to Fig.11 The antenna port configuration update component 1125 described above is performed.

[0194] At 1710, the method may include sending a set of multiple reference signals based on the updated antenna port configuration and based on an association between the updated antenna port configuration and a subband size for CSI reporting. The operations of 1710 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed as described in reference Fig.11 The described reference signal sending component 1130 is performed.

[0195] At 1715, the method may include receiving a CSI report including a CSI measurement based on a subband size and a set of multiple reference signals. The operations of 1715 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1715 may be performed as described in reference Fig.11 The described CSI reporting component 1135 is performed.

[0196] The following provides an overview of various aspects of the disclosure:

[0197] Aspect 1: A method for wireless communication at a UE, the method comprising: receiving a control signal indicating an updated antenna port configuration for the network entity from a network entity; receiving multiple reference signals from the network entity based at least in part on the updated antenna port configuration and at least in part on an association between the updated antenna port configuration and a subband size for reporting CSI; and sending a CSI report including a CSI measurement to the network entity, the CSI measurement being based at least in part on the subband size and the multiple reference signals.

[0198] Aspect 2: The method according to Aspect 1 also includes: receiving a second control signal from the network entity, wherein the second control signal configures a mapping from multiple antenna port numbers to multiple corresponding sub-band sizes, wherein the association between the updated antenna port configuration and the sub-band size is at least partially based on the mapping.

[0199] Aspect 3: A method according to Aspect 2, wherein the second control signal configures a first mapping from the multiple numbers of antenna ports to a first multiple corresponding subband sizes for PMI reporting, a second mapping from the multiple numbers of antenna ports to a second multiple corresponding subband sizes for CQI reporting, or both; and the CSI report includes PMI information based on the first multiple corresponding subband sizes, CQI information based on the second multiple corresponding subband sizes, or both.

[0200] Aspect 4: The method according to any one of Aspects 2 to 3, wherein the second control signal comprises an RRC signal.

[0201] Aspect 5: A method according to Aspect 1, wherein the UE is configured with multiple antenna port configurations for the network entity, the multiple antenna port configurations including a primary antenna port configuration and one or more secondary antenna port configurations, and the method further includes: receiving a second control signal from the network entity, the second control signal configuring a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to a secondary subband size, wherein the association between the updated antenna port configuration and the subband size is at least partially based on the mapping.

[0202] Aspect 6: A method according to Aspect 5, wherein the second control signal configures a first mapping from the primary antenna port configuration to a first primary subband size for PMI reporting and from the one or more secondary antenna ports configuration to a first secondary subband size for the PMI reporting, a second mapping from the primary antenna port configuration to a second primary subband size for CQI reporting and from the one or more secondary antenna ports configuration to a second secondary subband size for the CQI reporting, or both; and the CSI report includes PMI information according to the first primary subband size and the first secondary subband size, CQI information according to the second main subband size and the second secondary subband size, or both.

[0203] Aspect 7: The method according to any one of Aspects 5 to 6, wherein the second control signal comprises an RRC signal.

[0204] Aspect 8: The method according to any one of aspects 1 to 7, wherein the updated antenna port configuration indicates an updated number of active antenna ports for the network entity, an updated primary antenna port configuration for the network entity, or both.

[0205] Aspect 9: The method according to any one of Aspects 1 or 8 further includes: receiving a second control signal from the network entity, the second control signal configuring a first mapping from the number of antenna ports to the corresponding subband size; and determining an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes based at least in part on the first mapping and scaling operation, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the first mapping, the additional mapping, or both.

[0206] Aspect 10: The method according to aspect 9, wherein the second control signal further configures the scaling operation.

[0207] Aspect 11: The method according to any one of aspects 1 to 10, wherein the control signal comprises a DCI signal, a MAC-CE, or both.

[0208] Aspect 12: A method for wireless communication at a network entity, the method comprising: sending a control signal indicating an updated antenna port configuration for the network entity; sending multiple reference signals based at least in part on the updated antenna port configuration and at least in part on an association between the updated antenna port configuration and a subband size for CSI reporting; and receiving a CSI report including a CSI measurement, the CSI measurement being based at least in part on the subband size and the multiple reference signals.

[0209] Aspect 13: The method according to Aspect 12 also includes: sending a second control signal, wherein the second control signal configures a mapping from multiple antenna port numbers to multiple corresponding sub-band sizes, wherein the association between the updated antenna port configuration and the sub-band size is at least partially based on the mapping.

[0210] Aspect 14: A method according to Aspect 13, wherein the second control signal configures a first mapping from the multiple numbers of antenna ports to a first multiple corresponding subband sizes for PMI reporting, a second mapping from the multiple numbers of antenna ports to a second multiple corresponding subband sizes for CQI reporting, or both; and the CSI report includes PMI information based on the first multiple corresponding subband sizes, CQI information based on the second multiple corresponding subband sizes, or both.

[0211] Aspect 15: A method according to any one of Aspects 13 to 14, wherein the second control signal comprises an RRC signal.

[0212] Aspect 16: A method according to Aspect 12, wherein the network entity is configured with multiple antenna port configurations, the multiple antenna port configurations including a primary antenna port configuration and one or more secondary antenna port configurations, the method further comprising: sending a second control signal, the second control signal configuring a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to a secondary subband size, wherein the association between the updated antenna port configuration and the subband size is at least partially based on the mapping.

[0213] Aspect 17: A method according to Aspect 16, wherein the second control signal configures a first mapping from the primary antenna port configuration to a first primary subband size for PMI reporting and from the one or more secondary antenna ports configuration to a first secondary subband size for the PMI reporting, a second mapping from the primary antenna port configuration to a second primary subband size for CQI reporting and from the one or more secondary antenna ports configuration to a second secondary subband size for the CQI reporting, or both; and the CSI report includes PMI information according to the first primary subband size and the first secondary subband size, CQI information according to the second main subband size and the second secondary subband size, or both.

[0214] Aspect 18: A method according to any one of Aspects 16 to 17, wherein the second control signal comprises an RRC signal.

[0215] Aspect 19: The method according to any one of Aspects 12 to 18, further comprising: updating the number of active antenna ports for the network entity from a first number of antenna ports to a second number of antenna ports, wherein the updated antenna port configuration indicates the second number of antenna ports.

[0216] Aspect 20: The method according to any one of Aspects 12 to 19, further comprising: updating a primary antenna port configuration for the network entity from a first antenna port configuration to a second antenna port configuration, wherein the updated antenna port configuration indicates the second antenna port configuration.

[0217] Aspect 21: The method according to any one of Aspects 12, 19 or 20 further includes: sending a second control signal, which configures a first mapping from the number of antenna ports to the corresponding subband size; and determining an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes based at least in part on the first mapping and scaling operation, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the first mapping, the additional mapping, or both.

[0218] Aspect 22: The method according to aspect 21, wherein the second control signal further configures the scaling operation.

[0219] Aspect 23: The method according to any one of aspects 12 to 22, wherein the control signal comprises a DCI signal, a MAC-CE, or both.

[0220] Aspect 24: An apparatus for performing wireless communications at a UE, the apparatus comprising: a processor; and a memory, the memory being coupled to the processor and storing instructions, the instructions being executable by the processor to cause the apparatus to perform a method according to any one of Aspects 1 to 11.

[0221] Aspect 25: An apparatus for wireless communication at a UE, the apparatus comprising: at least one component for performing the method according to any one of aspects 1 to 11.

[0222] Aspect 26: A non-transitory computer-readable medium storing a code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method according to any one of aspects 1 to 11.

[0223] Aspect 27: An apparatus for wireless communication at a network entity, the apparatus comprising: a processor; and a memory, the memory being coupled to the processor and storing instructions, the instructions being executable by the processor to cause the apparatus to perform a method according to any one of Aspects 12 to 23.

[0224] Aspect 28: An apparatus for wireless communication at a network entity, the apparatus comprising: at least one component for performing the method according to any one of aspects 12 to 23.

[0225] Aspect 29: A non-transitory computer-readable medium storing code for wireless communication at a network entity, the code comprising instructions executable by a processor to perform the method according to any one of aspects 12 to 23.

[0226] It should be noted that the methods describe possible implementations, and that the operations and steps may be rearranged or otherwise modified, and that other implementations are possible. Furthermore, aspects from two or more methods may be combined.

[0227] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques 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.

[0228] Information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0229] The various illustrative blocks and components described in conjunction 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 functions associated with subband size determination for CSI reporting. A general purpose processor may be a microprocessor, but in an 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).

[0230] The functions associated with determining the subband size for CSI reporting may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions may be stored as one or more instructions or codes of a computer-readable medium, or sent using one or more instructions or codes of 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 may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these items. Features that implement the functions may also be physically located at different locations, including being distributed so that the functions are implemented at different physical locations.

[0231] Computer-readable medium includes both non-transient computer storage medium and communication medium, and the communication medium includes any medium that promotes computer program to be transferred from one location to another location.Non-transient storage medium can be any available medium that can be accessed by general or special-purpose computer.By way of example and not limitation, non-transient computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, disk storage device or other magnetic storage device, or can be used for carrying or storing desired program code parts and can be accessed by general or special-purpose computer or general or special-purpose processor in the form of instruction or data structure Any other non-transient medium.In addition, any connection is appropriately referred to as computer-readable medium.For example, if software is sent from website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of computer-readable medium. As used herein, disks and optical disks include CDs, laser disks, optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks. Disks can reproduce data magnetically, and optical disks can reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

[0232] As used herein, including in the claims, "or" used in a list of items (e.g., a list of items followed by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (in other words, A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted 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 "based at least in part on."

[0233] The term "determining" encompasses various actions and may include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, database or other data structure), or ascertaining, etc. Additionally, "determining" may include receiving (e.g., receiving information) or accessing (e.g., accessing data stored in a memory), etc. Additionally, "determining" may include resolving, retrieving, selecting, choosing, establishing, and other such similar actions.

[0234] In the drawings, similar components or features may have the same reference label. In addition, various components of the same type may be distinguished by following the reference label with a dash and a second label to distinguish between the similar components. If only the first reference label is used in the specification, the description may apply to any of the similar components having the same first reference label, regardless of the second or other subsequent reference labels.

[0235] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or within the scope of the claims. The term "example" as used herein means "used as an example, instance, or illustration," rather than "preferred" or "having advantages over other examples." The specific embodiments include specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0236] The description herein is provided to enable one of ordinary skill in the art to implement or use the present disclosure. Various modifications to the present disclosure will be apparent to one of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to a collection of examples and designs, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication at a user equipment (UE), the method comprising: receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity; receiving a plurality of reference signals from the network entity based at least in part on the updated antenna port configuration and based at least in part on an association between the updated antenna port configuration and a subband size for reporting channel state information; as well as A channel state information report including a channel state information measurement based at least in part on the subband size and the plurality of reference signals is sent to the network entity.

2. The method according to claim 1, further comprising: A second control signal is received from the network entity, the second control signal configuring a mapping from a plurality of numbers of antenna ports to a plurality of corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

3. The method according to claim 2, wherein: the second control signal configures a first mapping from the plurality of antenna port numbers to a first plurality of corresponding subband sizes for precoding matrix indicator reporting, a second mapping from the plurality of antenna port numbers to a second plurality of corresponding subband sizes for channel quality indicator reporting, or both; and The channel state information report includes precoding matrix indicator information according to the first plurality of corresponding subband sizes, channel quality indicator information according to the second plurality of corresponding subband sizes, or both. The method of claim 2 , wherein the second control signal comprises a radio resource control signal.

5. The method of claim 1 , wherein the UE is configured with multiple antenna port configurations for the network entity, the multiple antenna port configurations comprising a primary antenna port configuration and one or more secondary antenna port configurations, the method further comprising: A second control signal is received from the network entity, the second control signal configuring a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to a secondary subband size, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the mapping.

6. The method according to claim 5, wherein: the second control signal configures a first mapping from the primary antenna port configuration to a first primary subband size for precoding matrix indicator reporting and from the one or more secondary antenna ports configuration to a first secondary subband size for the precoding matrix indicator reporting, a second mapping from the primary antenna port configuration to a second primary subband size for channel quality indicator reporting and from the one or more secondary antenna ports configuration to a second secondary subband size for the channel quality indicator reporting, or both; and The channel state information report includes precoding matrix indicator information according to the first primary subband size and the first secondary subband size, channel quality indicator information according to the second primary subband size and the second secondary subband size, or both. The method of claim 5 , wherein the second control signal comprises a radio resource control signal.

8. The method of claim 1, wherein the updated antenna port configuration indicates an updated number of active antenna ports for the network entity, an updated primary antenna port configuration for the network entity, or both.

9. The method according to claim 1, further comprising: receiving a second control signal from the network entity, the second control signal configuring a first mapping from a number of antenna ports to corresponding subband sizes; as well as and determining, based at least in part on the first mapping and scaling operation, an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the first mapping, the additional mapping, or both.

10. The method of claim 9, wherein the second control signal further configures the scaling operation.

11. The method of claim 1, wherein the control signal comprises a downlink control information signal, a medium access control element, or both.

12. A method for wireless communication at a network entity, the method comprising: sending a control signal indicating an updated antenna port configuration for the network entity; transmitting a plurality of reference signals based at least in part on the updated antenna port configuration and based at least in part on an association between the updated antenna port configuration and a subband size for channel state information reporting; as well as The channel state information report is received including a channel state information measurement based at least in part on the subband size and the plurality of reference signals.

13. The method according to claim 12, further comprising: A second control signal is sent that configures a mapping from a plurality of numbers of antenna ports to a plurality of corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

14. The method according to claim 13, wherein: the second control signal configures a first mapping from the plurality of antenna port numbers to a first plurality of corresponding subband sizes for precoding matrix indicator reporting, a second mapping from the plurality of antenna port numbers to a second plurality of corresponding subband sizes for channel quality indicator reporting, or both; and The channel state information report includes precoding matrix indicator information according to the first plurality of corresponding subband sizes, channel quality indicator information according to the second plurality of corresponding subband sizes, or both.

15. The method of claim 13, wherein the second control signal comprises a radio resource control signal.

16. The method of claim 12, wherein the network entity is configured with a plurality of antenna port configurations, the plurality of antenna port configurations comprising a primary antenna port configuration and one or more secondary antenna port configurations, the method further comprising: and transmitting a second control signal that configures a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to secondary subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

17. The method of claim 16, wherein: the second control signal configures a first mapping from the primary antenna port configuration to a first primary subband size for precoding matrix indicator reporting and from the one or more secondary antenna ports configuration to a first secondary subband size for the precoding matrix indicator reporting, a second mapping from the primary antenna port configuration to a second primary subband size for channel quality indicator reporting and from the one or more secondary antenna ports configuration to a second secondary subband size for the channel quality indicator reporting, or both; and The channel state information report includes precoding matrix indicator information according to the first primary subband size and the first secondary subband size, channel quality indicator information according to the second primary subband size and the second secondary subband size, or both.

18. The method of claim 16, wherein the second control signal comprises a radio resource control signal.

19. The method according to claim 12, further comprising: A number of active antenna ports for the network entity is updated from a first number of antenna ports to a second number of antenna ports, wherein the updated antenna port configuration indicates the second number of antenna ports.

20. The method of claim 12, further comprising: A primary antenna port configuration for the network entity is updated from a first antenna port configuration to a second antenna port configuration, wherein the updated antenna port configuration indicates the second antenna port configuration.

21. The method of claim 12, further comprising: sending a second control signal, the second control signal configuring a first mapping from the number of antenna ports to corresponding subband sizes; as well as and determining, based at least in part on the first mapping and scaling operation, an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the first mapping, the additional mapping, or both.

22. The method of claim 21, wherein the second control signal further configures the scaling operation.

23. The method of claim 12, wherein the control signal comprises a downlink control information signal, a medium access control element, or both.

24. An apparatus for wireless communication at a user equipment (UE), the apparatus comprising: processor; and a memory coupled to the processor and storing instructions executable by the processor to cause the apparatus to: receiving a control signal from a network entity indicating an updated antenna port configuration for the network entity; receiving a plurality of reference signals from the network entity based at least in part on the updated antenna port configuration and based at least in part on an association between the updated antenna port configuration and a subband size for reporting channel state information; as well as A channel state information report including a channel state information measurement based at least in part on the subband size and the plurality of reference signals is sent to the network entity.

25. The apparatus of claim 24, wherein the instructions are further executable by the processor to cause the apparatus to: receive a second control signal from the network entity, the second control signal configuring a mapping from a plurality of antenna port numbers to a plurality of corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

26. The apparatus of claim 24, wherein the UE is configured with a plurality of antenna port configurations for the network entity, the plurality of antenna port configurations comprising a primary antenna port configuration and one or more secondary antenna port configurations, and the instructions are further executable by the processor to cause the apparatus to: A second control signal is received from the network entity, the second control signal configuring a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to a secondary subband size, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the mapping.

27. The apparatus of claim 24, wherein the instructions are further executable by the processor to cause the apparatus to: receiving a second control signal from the network entity, the second control signal configuring a first mapping from the number of antenna ports to corresponding subband sizes; and and determining, based at least in part on the first mapping and scaling operation, an additional mapping from one or more additional numbers of antenna ports to one or more additional corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband size is based at least in part on the first mapping, the additional mapping, or both.

28. An apparatus for wireless communication at a network entity, the apparatus comprising: processor; and a memory coupled to the processor and storing instructions executable by the processor to cause the apparatus to: sending a control signal indicating an updated antenna port configuration for the network entity; transmitting a plurality of reference signals based at least in part on the updated antenna port configuration and based at least in part on an association between the updated antenna port configuration and a subband size for channel state information reporting; as well as The channel state information report is received including a channel state information measurement based at least in part on the subband size and the plurality of reference signals.

29. The apparatus of claim 28, wherein the instructions are further executable by the processor to cause the apparatus to: send a second control signal that configures a mapping from a plurality of antenna port numbers to a plurality of corresponding subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

30. The apparatus of claim 28, wherein the network entity is configured with a plurality of antenna port configurations, the plurality of antenna port configurations comprising a primary antenna port configuration and one or more secondary antenna port configurations, and the instructions are further executable by the processor to cause the apparatus to: and transmitting a second control signal that configures a mapping from the primary antenna port configuration to a primary subband size and from the one or more secondary antenna port configurations to secondary subband sizes, wherein the association between the updated antenna port configuration and the subband sizes is based at least in part on the mapping.

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