Patent Publication Number: US-2022224494-A1

Title: Base station controlled temporal filtering of channel state information

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates generally to communication systems, and more particularly, to a wireless communication system with base station controlled temporal filtering of channel state information. 
     INTRODUCTION 
     Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems. 
     These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. An example telecommunication standard is 5G New Radio (NR). 5G NR is part of a continuous mobile broadband evolution promulgated by Third Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with Internet of Things (IoT)), and other requirements. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine type communications (mMTC), and ultra-reliable low latency communications (URLLC). Some aspects of 5G NR may be based on the 4G Long Term Evolution (LTE) standard. There exists a need for further improvements in 5G NR technology. These improvements may also be applicable to other multi-access technologies and the telecommunication standards that employ these technologies. 
     SUMMARY 
     The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later. 
     In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a user equipment (UE). The UE may receive, from a base station, a temporal filter configuration, and transmit, to the base station, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     In some aspects, whether the UE applies a temporal filter to a CSI measurement to generate the CSI value is based on the temporal filter configuration. 
     In some aspects, the temporal filter configuration identifies a temporal filter and the UE applies the identified temporal filter to a CSI measurement to generate the CSI value. 
     In some aspects, applying the temporal filter includes generating the CSI value based on the CSI measurement and a previous CSI measurement. 
     In some aspects, the UE is configured with a plurality of temporal filters, the temporal filter configuration identifies a temporal filter of the plurality of temporal filters, and the UE applies the identified temporal filter to a CSI measurement to generate the CSI value. 
     In some aspects, the CSI value is a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. 
     In some aspects, transmitting the CSI value includes transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     In some aspects, the temporal filter configuration is based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     In some aspects, the UE may receive, from the base station, a beam selection based on the CSI value. 
     In some aspects, the beam selection is based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and is based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
     In some aspects, transmitting the CSI value includes transmitting a CSI report, and the UE may select a beam corresponding to the CSI value from a plurality of beams for inclusion in the CSI report based on the CSI value. 
     In another aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a base station. The base station may transmit, to a user equipment (UE), a temporal filter configuration, and receive, from the UE, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     In some aspects, whether the CSI value is based on a temporal filter is based on the temporal filter configuration. 
     In some aspects, the temporal filter configuration identifies a temporal filter and the CSI value is generated by applying the temporal filter to a CSI measurement. 
     In some aspects, applying the temporal filter includes generating the CSI value based on the CSI measurement and a previous CSI measurement. 
     In some aspects, the UE is configured with a plurality of temporal filters, the temporal filter configuration identifies a temporal filter of the plurality of temporal filters, and the CSI value is generated by applying the identified temporal filter to a CSI measurement. 
     In some aspects, the CSI value is a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. 
     In some aspects, transmitting the CSI value includes transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     In some aspects, the temporal filter configuration is based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     In some aspects, the base station may transmit, to the UE, a beam selection based on the CSI value. 
     In some aspects, the beam selection is based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and is based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
     To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram illustrating an example of a wireless communications system and an access network. 
         FIGS. 2A, 2B, 2C, and 2D  are diagrams illustrating examples of a first 5G NR frame, DL channels within a 5G NR subframe, a second 5G NR frame, and UL channels within a 5G NR subframe, respectively. 
         FIG. 3  is a diagram illustrating an example of a base station and user equipment (UE) in an access network. 
         FIG. 4  is a communication flow diagram  400  illustrating CSI reporting and beam selection. 
         FIG. 5  is a diagram  500  illustrating a CSI report. 
         FIG. 6  is a communication flow diagram  600  illustrating CSI reporting and beam selection based on base station controlled filtering. 
         FIG. 7  is a flowchart of a method of wireless communication. 
         FIG. 8  is a flowchart of a method of wireless communication. 
         FIG. 9  is a diagram illustrating an example of a hardware implementation for an apparatus. 
         FIG. 10  is a diagram illustrating an example of a hardware implementation for an apparatus. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts. 
     Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements”). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. 
     By way of example, an element, or any portion of an element, or any combination of elements may be implemented as a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, systems on a chip (SoC), baseband processors, field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionality described throughout this disclosure. One or more processors in the processing system may execute software. Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. 
     Accordingly, in one or more example embodiments, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer-readable media includes computer storage media. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise a random-access memory (RAM), a read-only memory (ROM), an electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the aforementioned types of computer-readable media, or any other medium that can be used to store computer executable code in the form of instructions or data structures that can be accessed by a computer. 
       FIG. 1  is a diagram illustrating an example of a wireless communications system and an access network  100 . The wireless communications system (also referred to as a wireless wide area network (WWAN)) includes base stations  102 , UEs  104 , an Evolved Packet Core (EPC)  160 , and another core network  190  (e.g., a 5G Core (5GC)). The base stations  102  may include macrocells (high power cellular base station) and/or small cells (low power cellular base station). The macrocells include base stations. The small cells include femtocells, picocells, and microcells. 
     The base stations  102  configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) may interface with the EPC  160  through first backhaul links  132  (e.g., S1 interface). The base stations  102  configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN)) may interface with core network  190  through second backhaul links  184 . In addition to other functions, the base stations  102  may perform one or more of the following functions: transfer of user data, radio channel ciphering and deciphering, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection setup and release, load balancing, distribution for non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), subscriber and equipment trace, RAN information management (RIM), paging, positioning, and delivery of warning messages. The base stations  102  may communicate directly or indirectly (e.g., through the EPC  160  or core network  190 ) with each other over third backhaul links  134  (e.g., X2 interface). The first backhaul links  132 , the second backhaul links  184 , and the third backhaul links  134  may be wired or wireless. 
     The base stations  102  may wirelessly communicate with the UEs  104 . Each of the base stations  102  may provide communication coverage for a respective geographic coverage area  110 . There may be overlapping geographic coverage areas  110 . For example, the small cell  102 ′ may have a coverage area  110 ′ that overlaps the coverage area  110  of one or more macro base stations  102 . A network that includes both small cell and macrocells may be known as a heterogeneous network. A heterogeneous network may also include Home Evolved Node Bs (eNBs) (HeNBs), which may provide service to a restricted group known as a closed subscriber group (CSG). The communication links  120  between the base stations  102  and the UEs  104  may include uplink (UL) (also referred to as reverse link) transmissions from a UE  104  to a base station  102  and/or downlink (DL) (also referred to as forward link) transmissions from a base station  102  to a UE  104 . The communication links  120  may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and/or transmit diversity. The communication links may be through one or more carriers. The base stations  102 /UEs  104  may use spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc. MHz) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x component carriers) used for transmission in each direction. The carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL). The component carriers may include a primary component carrier and one or more secondary component carriers. A primary component carrier may be referred to as a primary cell (PCell) and a secondary component carrier may be referred to as a secondary cell (SCell). 
     Certain UEs  104  may communicate with each other using device-to-device (D2D) communication link  158 . The D2D communication link  158  may use the DL/UL WWAN spectrum. The D2D communication link  158  may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH), a physical sidelink discovery channel (PSDCH), a physical sidelink shared channel (PSSCH), and a physical sidelink control channel (PSCCH). D2D communication may be through a variety of wireless D2D communications systems, such as for example, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard, LTE, or NR. 
     The wireless communications system may further include a Wi-Fi access point (AP)  150  in communication with Wi-Fi stations (STAs)  152  via communication links  154  in a 5 GHz unlicensed frequency spectrum. When communicating in an unlicensed frequency spectrum, the STAs  152 /AP  150  may perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available. 
     The small cell  102 ′ may operate in a licensed and/or an unlicensed frequency spectrum. When operating in an unlicensed frequency spectrum, the small cell  102 ′ may employ NR and use the same 5 GHz unlicensed frequency spectrum as used by the Wi-Fi AP  150 . The small cell  102 ′, employing NR in an unlicensed frequency spectrum, may boost coverage to and/or increase capacity of the access network. 
     A base station  102 , whether a small cell  102 ′ or a large cell (e.g., macro base station), may include and/or be referred to as an eNB, gNodeB (gNB), or another type of base station. Some base stations, such as gNB  180  may operate in a traditional sub 6 GHz spectrum, in millimeter wave (mmW) frequencies, and/or near mmW frequencies in communication with the UE  104 . When the gNB  180  operates in mmW or near mmW frequencies, the gNB  180  may be referred to as an mmW base station. Extremely high frequency (EHF) is part of the RF in the electromagnetic spectrum. EHF has a range of 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10 millimeters. Radio waves in the band may be referred to as a millimeter wave. Near mmW may extend down to a frequency of 3 GHz with a wavelength of 100 millimeters. The super high frequency (SHF) band extends between 3 GHz and 30 GHz, also referred to as centimeter wave. Frequency range bands include frequency range 1 (FR1), which includes frequency bands below 7.225 GHz, and frequency range 2 (FR2), which includes frequency bands above 24.250 GHz. Communications using the mmW/near mmW radio frequency (RF) band (e.g., 3 GHz-300 GHz) has extremely high path loss and a short range. Base stations/UEs may operate within one or more frequency range bands. The mmW base station  180  may utilize beamforming  182  with the UE  104  to compensate for the extremely high path loss and short range. The base station  180  and the UE  104  may each include a plurality of antennas, such as antenna elements, antenna panels, and/or antenna arrays to facilitate the beamforming. 
     The base station  180  may transmit a beamformed signal to the UE  104  in one or more transmit directions  182 ′. The UE  104  may receive the beamformed signal from the base station  180  in one or more receive directions  182 ″. The UE  104  may also transmit a beamformed signal to the base station  180  in one or more transmit directions. The base station  180  may receive the beamformed signal from the UE  104  in one or more receive directions. The base station  180 /UE  104  may perform beam training to determine the best receive and transmit directions for each of the base station  180 /UE  104 . The transmit and receive directions for the base station  180  may or may not be the same. The transmit and receive directions for the UE  104  may or may not be the same. 
     The EPC  160  may include a Mobility Management Entity (MME)  162 , other MMES  164 , a Serving Gateway  166 , a Multimedia Broadcast Multicast Service (MBMS) Gateway  168 , a Broadcast Multicast Service Center (BM-SC)  170 , and a Packet Data Network (PDN) Gateway  172 . The MME  162  may be in communication with a Home Subscriber Server (HSS)  174 . The MME  162  is the control node that processes the signaling between the UEs  104  and the EPC  160 . Generally, the MME  162  provides bearer and connection management. All user Internet protocol (IP) packets are transferred through the Serving Gateway  166 , which itself is connected to the PDN Gateway  172 . The PDN Gateway  172  provides UE IP address allocation as well as other functions. The PDN Gateway  172  and the BM-SC  170  are connected to the IP Services  176 . The IP Services  176  may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a PS Streaming Service, and/or other IP services. The BM-SC  170  may provide functions for MBMS user service provisioning and delivery. The BM-SC  170  may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN), and may be used to schedule MBMS transmissions. The MBMS Gateway  168  may be used to distribute MBMS traffic to the base stations  102  belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and may be responsible for session management (start/stop) and for collecting eMBMS related charging information. 
     The core network  190  may include a Access and Mobility Management Function (AMF)  192 , other AMFs  193 , a Session Management Function (SMF)  194 , and a User Plane Function (UPF)  195 . The AMF  192  may be in communication with a Unified Data Management (UDM)  196 . The AMF  192  is the control node that processes the signaling between the UEs  104  and the core network  190 . Generally, the AMF  192  provides QoS flow and session management. All user Internet protocol (IP) packets are transferred through the UPF  195 . The UPF  195  provides UE IP address allocation as well as other functions. The UPF  195  is connected to the IP Services  197 . The IP Services  197  may include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a Packet Switch (PS) Streaming (PSS) Service, and/or other IP services. 
     The base station may include and/or be referred to as a gNB, Node B, eNB, an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (BSS), an extended service set (ESS), a transmit reception point (TRP), or some other suitable terminology. The base station  102  provides an access point to the EPC  160  or core network  190  for a UE  104 . Examples of UEs  104  include a cellular phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (e.g., MP3 player), a camera, a game console, a tablet, a smart device, a wearable device, a vehicle, an electric meter, a gas pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functioning device. Some of the UEs  104  may be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicles, heart monitor, etc.). The UE  104  may also be referred to as a station, a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. 
     Referring again to  FIG. 1 , in certain aspects, the base station  180  may include a temporal filter configuration component  198  configured to determine a temporal filter configuration for a UE and to transmit the temporal filter configuration to the UE. In certain aspects, the UE  104  may include a configuration reception component  199  configured to receive a temporal filter configuration and to generate CSI values based on the temporal filter configuration. Although the following description may be focused on 5G NR, the concepts described herein may be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies. 
       FIG. 2A  is a diagram  200  illustrating an example of a first subframe within a 5G NR frame structure.  FIG. 2B  is a diagram  230  illustrating an example of DL channels within a 5G NR subframe.  FIG. 2C  is a diagram  250  illustrating an example of a second subframe within a 5G NR frame structure.  FIG. 2D  is a diagram  280  illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure may be frequency division duplexed (FDD) in which for a particular set of subcarriers (carrier system bandwidth), subframes within the set of subcarriers are dedicated for either DL or UL, or may be time division duplexed (TDD) in which for a particular set of subcarriers (carrier system bandwidth), subframes within the set of subcarriers are dedicated for both DL and UL. In the examples provided by  FIGS. 2A, 2C , the 5G NR frame structure is assumed to be TDD, with subframe 4 being configured with slot format 28 (with mostly DL), where D is DL, U is UL, and F is flexible for use between DL/UL, and subframe 3 being configured with slot format 34 (with mostly UL). While subframes 3, 4 are shown with slot formats 34, 28, respectively, any particular subframe may be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. UEs are configured with the slot format (dynamically through DL control information (DCI), or semi-statically/statically through radio resource control (RRC) signaling) through a received slot format indicator (SFI). Note that the description infra applies also to a 5G NR frame structure that is TDD. 
     Other wireless communication technologies may have a different frame structure and/or different channels. A frame (10 ms) may be divided into 10 equally sized subframes (1 ms). Each subframe may include one or more time slots. Subframes may also include mini-slots, which may include 7, 4, or 2 symbols. Each slot may include 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot may include 14 symbols, and for slot configuration 1, each slot may include 7 symbols. The symbols on DL may be cyclic prefix (CP) OFDM (CP-OFDM) symbols. The symbols on UL may be CP-OFDM symbols (for high throughput scenarios) or discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbols (also referred to as single carrier frequency-division multiple access (SC-FDMA) symbols) (for power limited scenarios; limited to a single stream transmission). The number of slots within a subframe is based on the slot configuration and the numerology. For slot configuration 0, different numerologies μ 0 to 4 allow for 1, 2, 4, 8, and 16 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols/slot and 2 μ  slots/subframe. The subcarrier spacing and symbol length/duration are a function of the numerology. The subcarrier spacing may be equal to 2 μ *15 kHz, where μ is the numerology 0 to 4. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=4 has a subcarrier spacing of 240 kHz. The symbol length/duration is inversely related to the subcarrier spacing.  FIGS. 2A-2D  provide an example of slot configuration 0 with 14 symbols per slot and numerology μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a set of frames, there may be one or more different bandwidth parts (BWPs) (see  FIG. 2B ) that are frequency division multiplexed. Each BWP may have a particular numerology. 
     A resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs)) that extends 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme. 
     As illustrated in  FIG. 2A , some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include demodulation RS (DM-RS) (indicated as R x  for one particular configuration, where  100   x  is the port number, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS), beam refinement RS (BRRS), and phase tracking RS (PT-RS). 
       FIG. 2B  illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs), each CCE including nine RE groups (REGs), each REG including four consecutive REs in an OFDM symbol. A PDCCH within one BWP may be referred to as a control resource set (CORESET). Additional BWPs may be located at greater and/or lower frequencies across the channel bandwidth. A primary synchronization signal (PSS) may be within symbol  2  of particular subframes of a frame. The PSS is used by a UE  104  to determine subframe/symbol timing and a physical layer identity. A secondary synchronization signal (SSS) may be within symbol  4  of particular subframes of a frame. The SSS is used by a UE to determine a physical layer cell identity group number and radio frame timing. Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI). Based on the PCI, the UE can determine the locations of the aforementioned DM-RS. The physical broadcast channel (PBCH), which carries a master information block (MIB), may be logically grouped with the PSS and SSS to form a synchronization signal (SS)/PBCH block (also referred to as SS block (SSB)). The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN). The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs), and paging messages. 
     As illustrated in  FIG. 2C , some of the REs carry DM-RS (indicated as R for one particular configuration, but other DM-RS configurations are possible) for channel estimation at the base station. The UE may transmit DM-RS for the physical uplink control channel (PUCCH) and DM-RS for the physical uplink shared channel (PUSCH). The PUSCH DM-RS may be transmitted in the first one or two symbols of the PUSCH. The PUCCH DM-RS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. The UE may transmit sounding reference signals (SRS). The SRS may be transmitted in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a base station for channel quality estimation to enable frequency-dependent scheduling on the UL. 
       FIG. 2D  illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, a channel quality indicator (CQI), a precoding matrix indicator (PMI), a rank indicator (RI), and hybrid automatic repeat request (HARQ) ACK/NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR), a power headroom report (PHR), and/or UCI. 
       FIG. 3  is a block diagram of a base station  310  in communication with a UE  350  in an access network. In the DL, IP packets from the EPC  160  may be provided to a controller/processor  375 . The controller/processor  375  implements layer 3 and layer 2 functionality. Layer 3 includes a radio resource control (RRC) layer, and layer 2 includes a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, and a medium access control (MAC) layer. The controller/processor  375  provides RRC layer functionality associated with broadcasting of system information (e.g., MIB, SIBs), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter radio access technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functionality associated with header compression/decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with the transfer of upper layer packet data units (PDUs), error correction through ARQ, concatenation, segmentation, and reassembly of RLC service data units (SDUs), re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization. 
     The transmit (TX) processor  316  and the receive (RX) processor  370  implement layer 1 functionality associated with various signal processing functions. Layer 1, which includes a physical (PHY) layer, may include error detection on the transport channels, forward error correction (FEC) coding/decoding of the transport channels, interleaving, rate matching, mapping onto physical channels, modulation/demodulation of physical channels, and MIMO antenna processing. The TX processor  316  handles mapping to signal constellations based on various modulation schemes (e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation (M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to an OFDM subcarrier, multiplexed with a reference signal (e.g., pilot) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to produce a physical channel carrying a time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce multiple spatial streams. Channel estimates from a channel estimator  374  may be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE  350 . Each spatial stream may then be provided to a different antenna  320  via a separate transmitter  318 TX. Each transmitter  318 TX may modulate an RF carrier with a respective spatial stream for transmission. 
     At the UE  350 , each receiver  354 RX receives a signal through its respective antenna  352 . Each receiver  354 RX recovers information modulated onto an RF carrier and provides the information to the receive (RX) processor  356 . The TX processor  368  and the RX processor  356  implement layer 1 functionality associated with various signal processing functions. The RX processor  356  may perform spatial processing on the information to recover any spatial streams destined for the UE  350 . If multiple spatial streams are destined for the UE  350 , they may be combined by the RX processor  356  into a single OFDM symbol stream. The RX processor  356  then converts the OFDM symbol stream from the time-domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, and the reference signal, are recovered and demodulated by determining the most likely signal constellation points transmitted by the base station  310 . These soft decisions may be based on channel estimates computed by the channel estimator  358 . The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station  310  on the physical channel. The data and control signals are then provided to the controller/processor  359 , which implements layer 3 and layer 2 functionality. 
     The controller/processor  359  can be associated with a memory  360  that stores program codes and data. The memory  360  may be referred to as a computer-readable medium. In the UL, the controller/processor  359  provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the EPC  160 . The controller/processor  359  is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations. 
     Similar to the functionality described in connection with the DL transmission by the base station  310 , the controller/processor  359  provides RRC layer functionality associated with system information (e.g., MIB, SIBs) acquisition, RRC connections, and measurement reporting; PDCP layer functionality associated with header compression/decompression, and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functionality associated with the transfer of upper layer PDUs, error correction through ARQ, concatenation, segmentation, and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functionality associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction through HARQ, priority handling, and logical channel prioritization. 
     Channel estimates derived by a channel estimator  358  from a reference signal or feedback transmitted by the base station  310  may be used by the TX processor  368  to select the appropriate coding and modulation schemes, and to facilitate spatial processing. The spatial streams generated by the TX processor  368  may be provided to different antenna  352  via separate transmitters  354 TX. Each transmitter  354 TX may modulate an RF carrier with a respective spatial stream for transmission. 
     The UL transmission is processed at the base station  310  in a manner similar to that described in connection with the receiver function at the UE  350 . Each receiver  318 RX receives a signal through its respective antenna  320 . Each receiver  318 RX recovers information modulated onto an RF carrier and provides the information to a RX processor  370 . 
     The controller/processor  375  can be associated with a memory  376  that stores program codes and data. The memory  376  may be referred to as a computer-readable medium. In the UL, the controller/processor  375  provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE  350 . IP packets from the controller/processor  375  may be provided to the EPC  160 . The controller/processor  375  is also responsible for error detection using an ACK and/or NACK protocol to support HARQ operations. 
     At least one of the TX processor  368 , the RX processor  356 , and the controller/processor  359  may be configured to perform aspects in connection with  198  of  FIG. 1 . 
     At least one of the TX processor  316 , the RX processor  370 , and the controller/processor  375  may be configured to perform aspects in connection with  198  of  FIG. 1 . 
       FIG. 4  is a communication flow diagram  400  illustrating CSI reporting and beam selection. A UE  402  may communicate with a base station  404  using a particular beam or beams for uplink or downlink. As illustrated at  412 , the UE  402  may perform CSI measurement. The UE  402  may take measurements for different beams representative of the quality of the channel for that beam. For example, the UE  402  may measure the signal to noise and interference ratio (SINR), the reference signal received power (RSRP), the received signal strength indicator (RSSI), reference signal received quality (RSRQ) for various beams. 
     As illustrated at  414 , the UE  402  may apply a temporal filter to the CSI measurements for a beam to generate a CSI value to report for that beam. Some UEs may simply report the measured CSI value for a beam. Some UEs may modify the CSI measurements, by applying a temporal filter, and report the filtered CSI measurement. Whether a temporal filter is applied and what temporal filter is applied is a matter of UE implementation. 
     As illustrated at  420 , the UE  402  transmits a CSI report  420  to the base station  404  and the base station  404  receives the CSI report  420 . The CSI report  420  includes CSI values for corresponding beams. If the UE  402  did not apply a temporal filter at  414 , the CSI values will be the CSI measurements taken at  412 . If the UE  402  applied a temporal filter at  414 , the CSI values may be representative of the channel for the beam and may be based on the CSI measurements taken at  412 , but will be determined by the temporal filter. 
     As illustrated at  422 , the base station  404  determines a beam selection for the UE  402 . The base station  404  will select a beam for uplink and/or downlink communication between the base station  404  and the UE  402 . The base station  404  may select the beam, at least in part, based on the CSI values for the beams received in the CSI report  420 . The base station  404  may transmit the beam selection  424  to the UE  402  (e.g., in a beam report) and the UE  402  may receive the beam selection  424 . 
     As illustrated at  430 , the UE  402  may transmit uplink transmissions to the base station  404  on the beam identified in the beam selection  424  and the base station  404  may receive the uplink transmissions on the beam identified in the beam selection  424 , and the base station  404  may transmit downlink transmissions to the UE  402  on the beam identified in the beam selection  424  and the UE  402  may receive the downlink transmissions on the beam identified in the beam selection  424 . 
       FIG. 5  is a diagram  500  illustrating a CSI report. A CSI report may include a report number field to identify the report. The CSI report may include a first set of fields  512  containing beam identifiers. The beam identifiers identify which beams the CSI report is providing CSI values for. For example, the beam identifier may be a CSI-RS resource indicator (CRI) or may be a SS/PBSCH Block Indicator (SSBRI). 
     The CSI report may include a second set of fields  514  containing CSI values. For example, the CSI value may be a channel quality indicator (CQI), a precoding matrix indicator (PMI), a strongest layer indication (SLI), a rank indication (RI), a RSRP such as L1-RSRP, or a SINR such as L1-SINR. Each field of the second set of fields  514  may correspond to a field in the first set of fields  512 . The CSI value in a field is for the beam identified in the corresponding field. 
     In some aspects, each field in the second set of fields  514  may include the CSI value for the corresponding beam. In some other aspects, one of the fields (e.g., the first field) may include the CSI value for the corresponding beam, and some or all of the remaining fields may include a differential value, identifying how much the CSI value for that beam differs from the CSI value in the field that does not have a differential value. 
     A CSI report may have a limited number of fields, and may therefore only report CSI information for a limited number of beams. For example, the CSI report illustrated in the diagram  500  may only report CSI values for up to four beams. In some other examples, a CSI report may only include CSI information for one or two beams. A UE may have access to multiple beams and may have CSI information for multiple beams, but a CSI report may not have enough fields to report the CSI information for all of the multiple beams. The UE may select a subset of those beams to be included in the CSI report. For example, the UE may select the beams with the highest CSI values (e.g., the highest SINR or the highest RSRP) to be included in the CSI report. 
     In some environments, transient interference may cause a temporary reduction in channel quality for a beam. For example, the SINR for a beam may change drastically because of cross-link interference from other cells. This may especially true in indoor environments and/or environments with many close cells. Although a beam may experience a drop in channel quality based on a transient interference, that beam may still be the optimal beam for future scheduling. However, the transient drop in channel quality may result in a reduced CSI measurement, and the UE may not select the beam for inclusion in the CSI report. With the beam not being included in the CSI report, the base station may not be able to select the beam for scheduling or may not have reduced information at its disposal for making scheduling decisions. 
       FIG. 6  is a communication flow diagram  600  illustrating CSI reporting and beam selection based on base station controlled temporal filtering. A UE  602  may communicate with a base station  604  using a particular beam or beams for uplink or downlink. The UE  602  may be configured with one or more temporal filter, and the base station  604  may configure whether the UE  602  will use a filter in CSI reporting or which filter the UE  602  will use in CSI reporting. 
     A temporal filter may be a filter which a UE applies to CSI measurements for a beam to generate a CSI value for that beam that is based on CSI measurements over time. One example of a temporal filter may be a weighted combination of the current CSI measurement and previous CSI measurements. For example, a filter may indicate that a CSI value for a beam should be 0.6*SINR NEW +0.3*SINR LAsT +0.3*SINR LAST+1 , where SINR NEw  is the current SINR measurement for that beam, SINR LAST  is the previous SINR measurement for that beam, and SINR LAST+1  is the SINR measurement before SINR LAsT  for that beam. 
     A second example of a temporal filter may be a weighted combination of the current CSI measurement and the last reported CSI value. For example, a filter may indicate that a CSI value for a beam should be 0.7*SINR NEW +0.3*SINR OLD , where SINR NEW  is the current SINR measurement for that beam and SINR OLD  is the last reported CSI value for that beam (which may also have been generated based on the filter). 
     A third example of a temporal filter may be the average of a CSI measurement over a time window (e.g., a set or configured time window corresponding to that temporal filter). For example, a filter may indicate that a CSI value for a beam should be the average measured SINR over the last 100 ms, or over the last 20 ms, or over the last 80 slots. 
     A fourth example of a temporal filter may be a reduction of a CSI measurement based on the standard deviation or variance of that CSI measurement. The standard deviation or variance may be calculated based on measurements of that CSI measurement during a set or configured time window, or based on a set or configured number of the most recent measurements. For example, a filter may indicate that a CSI value for a beam should be SINR NEW −X*SD(SINR), where SINRNEW is the current SINR measurement, SD(SINR) is the standard deviation of SINR measurements, and X is a set or configured coefficient. 
     Although the above examples use SINR as an example CSI measurement, the same filters may be applied to other CSI measurements such as RSRP. 
     As illustrated at  612 , the base station  604  may determine a temporal filter configuration. A temporal filter configuration may set the behavior of a UE receiving the temporal filter configuration with respect to applying temporal filters. For example, a temporal filter configuration may indicate whether a temporal filter should be applied, which temporal filter should be applied, and/or what values to use in a temporal filter. In some aspects, a temporal filter configuration may indicate that a UE receiving the temporal filter configuration should apply a temporal filter to generate reported CSI values. In some aspects, a temporal filter configuration may also indicate that a UE receiving the temporal configuration should not apply a temporal filter to generate reported CSI values. In other aspects, a UE may default to applying a temporal filter or may default to not applying a temporal filter, and the temporal filter configuration may indicate to the receiving UE to switch from its default behavior. 
     In some aspects, a UE (such as the UE  602 ) may be configured with a single temporal filter, and the temporal filter configuration may simply indicate whether to use the single temporal filter. In other aspects, a UE (such as the UE  602 ) may be configured with multiple temporal filters, and the temporal filter configuration may identify which temporal filter to apply. In some aspects, a temporal filter configuration may indicate which temporal filter a receiving UE should apply or may indicate that the UE should not apply a temporal filter. 
     In some aspects, a temporal filter configuration may set values to be used in a temporal filter. For example, where a temporal filter applies weights to measurements or values to be combined, the temporal filter configuration may set those weights. Where a temporal filter determines an average, a standard deviation, or a variance over a certain time window, the temporal filter configuration may set the length of the time window. 
     In some aspects, the base station  604  may determine the temporal filter configuration at  612  based on values reported by UEs, or rates of change in those values, that may correspond to interference. For example, the base station  604  may determine the temporal filter configuration based on a history of HARQ reports, based on a rate of change in reported CSI values, and/or based on a rate of change in CQI reported. Whether a temporal filter should be applied, which temporal filter should be applied, and/or what values to use in a temporal filter may be set based on the values or reports. For example, if the base station  604  determines that the rate of change in CSI values is above a threshold value, the base station  604  may determine the temporal filter configuration to indicate that the UE should apply a temporal filter, or if the base station  604  determines that the rate of change in CSI values is within a specified range, the base station  604  may determine the temporal filter configuration to indicate that the UE should apply a specific temporal filter within that range. The base station  604  may determine the temporal filter configuration to set the length of the window used in an averaging temporal filter based on the rate of change in CSI values, setting a longer window where a higher rate of change is determined. 
     The base station  604  may determine the temporal filter configuration for a UE based on reports from that UE or based on reports from other UEs communicating with the base station  604 . For example, in determining the temporal filter configuration for a first UE, the base station  604  may determine that other UEs in the area may be experiencing interference (e.g., are experiencing high rates of change in reported CSI values), and may determine the temporal filter configuration for the first UE based on the other UEs in the area experiencing interference. 
     In some aspects, the base station  604  may determine the temporal filter configuration at  612  based on values determined at the base station  604 . For example, the base station  604  may determine the quality of uplink reception from a UE, and may determine the temporal filter configuration for that UE based on the quality of the uplink reception. As another example, the base station  604  may determine a ratio of retransmission requests received from a UE to the number of transmissions sent to the UE, and may determine the temporal filter configuration for that UE based on the ratio. 
     In some aspects, the UE  602  may be preconfigured with one or more temporal filter. For example, one or more temporal filter may be included in a standard and the UE  602  may be programmed to include the one or more filter based on the standard. The temporal filter configuration may include an indicator identifying a preconfigured temporal filter that should be used. In some aspects, a temporal filter configuration may additionally or alternatively include the temporal filter itself (e.g., a temporal filter that is not preconfigured for the UE  602 ). 
     Upon determining a temporal filter configuration for the UE  602 , the base station  604  may transmit the temporal filter configuration  614  to the UE  602  and the UE  602  may receive the temporal filter configuration  614 . In some aspects, the base station  604  may transmit the temporal filter configuration  614  in an RRC message as part of CSI report setting. In some aspects, the base station  604  may transmit the temporal filter configuration  614  in dynamic signaling, such as DCI or downlink MAC CE. For example, the base station  604  may transmit the temporal filter configuration  614  as part of a message triggering aperiodic CSI reporting. In some aspects, the base station  604  may determine one temporal filter configuration at  612  for multiple UEs, and may transmit the temporal filter configuration to multiple UEs. For example, the base station  604  may transmit the temporal filter configuration in a group-common DCI or downlink MAC CE. 
     As illustrated at  622 , the UE  602  may perform CSI measurements. The UE  402  may take measurements for different beams representative of the quality of the channel for that beam. For example, the UE  402  may measure the SINR, the RSRP, the RSSI, or the RSRQ for various beams. 
     As illustrated at  624 , the UE  602  may generate CSI values for beams based on the CSI measurements and based on the temporal filter configuration  614 . If the temporal filter configuration  614  indicates that a temporal filter should not be used, the UE  602  may generate the CSI values to be the raw CSI measurements. If the temporal filter configuration  614  identified a filter, the UE  602  may apply that filter to the CSI measurements and the relevant past CSI measurements or reported CSI values to generate the CSI values. If the temporal filter configuration  614  included a value to be used in the temporal filter, the UE  602  may apply the filter using that value. 
     Upon generating the CSI values for the beams, the UE  602  may transmit a CSI report  626  to the base station  604  and the base station  604  may receive the CSI report  626 . The CSI report  626  includes CSI values generated at  624  based on the temporal filter configuration. The UE  602  may select a subset of the CSI values generated to be included in the CSI report  626  (e.g., may select the highest CSI values). 
     As illustrated at  632 , the base station  604  may determine a beam selection for the UE  602 . The base station  604  may select an uplink beam or may select a downlink beam for the UE  602  based on the CSI values for the beams in the CSI report  626 . Where a temporal filter was applied to generate the CSI values, a beam that was experiencing a transient interference, resulting in a low CSI measurement at  622 , may nonetheless have been included in the CSI report  626  due to the temporal filter causing past high CSI measurements to influence the beam&#39;s CSI value. The beam may be selected as an uplink beam or as a downlink beam in spite of the transient interference. 
     The base station  604  may apply a scheduling algorithm at  632  to determine which beam is selected. The scheduling algorithm may select multiple beams for multiple UEs based on the CSI values received from those UEs as well as other factors such as traffic statistics and history of packet errors. In some aspects, the scheduling algorithm applied may be based on the temporal filter configuration  614  transmitted to the UE  602 . For example, the base station  604  may apply a first scheduling algorithm if the temporal filter configuration  614  indicated that the UE  602  should not apply a temporal filter and may apply a second, different scheduling algorithm if the temporal filter configuration  614  indicated that the UE  602  should apply a temporal filter. In some aspects, for example, the first scheduling algorithm and the second scheduling algorithm may include different coefficients in the proportionally fair (PF) scheduling algorithm. 
     Upon determining the beam selection for the UE  602  at  632 , the base station  604  may transmit the beam selection  634  to the UE  602  and the UE  602  may receive the beam selection  634 . As illustrated at  640 , if the selected beam is selected as an uplink beam, the UE  602  may transmit uplink transmissions to the base station  604  on the beam identified in the beam selection  624  and the base station  604  may receive the uplink transmissions on the beam identified in the beam selection  624 . If the selected beam is selected as a downlink beam, the base station  604  may transmit downlink transmissions to the UE  602  on the beam identified in the beam selection  624  and the UE  602  may receive the downlink transmissions on the beam identified in the beam selection  634 . 
       FIG. 7  is a flowchart  700  of a method of wireless communication. The method may be performed by a UE (e.g., the UE  104 ,  602 ; the apparatus  902 ). 
     At  702 , the UE may receive, from a base station, a temporal filter configuration. The temporal filter configuration may be based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     At  704 , the UE may transmit, to the base station, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. Whether the UE applies a temporal filter to a CSI measurement to generate the CSI value may be based on the temporal filter configuration. The temporal filter configuration may identify a temporal filter and the UE may apply the identified temporal filter to a CSI measurement to generate the CSI value. Applying the temporal filter may include generating the CSI value based on the CSI measurement and a previous CSI measurement. The UE may be configured with a plurality of temporal filters, the temporal filter configuration may identify a temporal filter of the plurality of temporal filters, and the UE may apply the identified temporal filter to a CSI measurement to generate the CSI value. 
     The CSI value may be a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. Transmitting the CSI value may include transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     In some aspects, the UE may receive, from the base station, a beam selection based on the CSI value. The beam selection may be based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and may be based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
     In some aspects, transmitting the CSI value may include transmitting a CSI report, and the UE may select a beam corresponding to the CSI value from a plurality of beams for inclusion in the CSI report based on the CSI value. 
       FIG. 8  is a flowchart  800  of a method of wireless communication. The method may be performed by a base station (e.g., the base station  102 / 180 ,  604 ; the apparatus  1002 . 
     At  802 , the base station may transmit, to a user equipment (UE), a temporal filter configuration. The temporal filter configuration may be based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     At  804 , the base station may receive, from the UE, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. Whether the CSI value is based on a temporal filter may be based on the temporal filter configuration. The temporal filter configuration may identify a temporal filter and the CSI value may be generated by applying the temporal filter to a CSI measurement. Applying the temporal filter may include generating the CSI value based on the CSI measurement and a previous CSI measurement. The UE may be configured with a plurality of temporal filters, the temporal filter configuration may identify a temporal filter of the plurality of temporal filters, and the CSI value may be generated by applying the identified temporal filter to a CSI measurement. 
     The CSI value may be a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. Transmitting the CSI value may include transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     In some aspects, the base station may transmit, to the UE, a beam selection based on the CSI value. The beam selection may be based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and may be based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
       FIG. 9  is a diagram  900  illustrating an example of a hardware implementation for an apparatus  902 . The apparatus  902  is a UE and includes a cellular baseband processor  904  (also referred to as a modem) coupled to a cellular RF transceiver  922  and one or more subscriber identity modules (SIM) cards  920 , an application processor  906  coupled to a secure digital (SD) card  908  and a screen  910 , a Bluetooth module  912 , a wireless local area network (WLAN) module  914 , a Global Positioning System (GPS) module  916 , and a power supply  918 . The cellular baseband processor  904  communicates through the cellular RF transceiver  922  with the UE  104  and/or BS  102 / 180 . The cellular baseband processor  904  may include a computer-readable medium/memory. The computer-readable medium/memory may be non-transitory. The cellular baseband processor  904  is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the cellular baseband processor  904 , causes the cellular baseband processor  904  to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the cellular baseband processor  904  when executing software. The cellular baseband processor  904  further includes a reception component  930 , a communication manager  932 , and a transmission component  934 . The communication manager  932  includes the one or more illustrated components. The components within the communication manager  932  may be stored in the computer-readable medium/memory and/or configured as hardware within the cellular baseband processor  904 . The cellular baseband processor  904  may be a component of the UE  350  and may include the memory  360  and/or at least one of the TX processor  368 , the RX processor  356 , and the controller/processor  359 . In one configuration, the apparatus  902  may be a modem chip and include just the baseband processor  904 , and in another configuration, the apparatus  902  may be the entire UE (e.g., see  350  of  FIG. 3 ) and include the aforediscussed additional modules of the apparatus  902 . 
     The communication manager  932  includes a temporal filter configuration component  940  that is configured to receive, from a base station (such as base station  102 / 180 ), a temporal filter configuration, e.g., as described in connection with  702  of  FIG. 7 . The communication manager  932  further includes a CSI value component  942  that receives input in the form of instructions for determining a CSI value from the temporal filter configuration component  940 , based on the received temporal filter configuration, and is configured to determine a CSI value based on the instructions and transmit, to the base station, the CSI value, the CSI value being based on the temporal filter configuration, e.g., as described in connection with  704  of  FIG. 7 . 
     The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of  FIG. 7 . As such, each block in the aforementioned flowchart of  FIG. 7  may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof. 
     In one configuration, the apparatus  902 , and in particular the cellular baseband processor  904 , includes means for receiving, from a base station, a temporal filter configuration and means for transmitting, to the base station, a CSI value, the CSI value being based on the temporal filter configuration. The aforementioned means may be one or more of the aforementioned components of the apparatus  902  configured to perform the functions recited by the aforementioned means. As described supra, the apparatus  902  may include the TX Processor  368 , the RX Processor  356 , and the controller/processor  359 . As such, in one configuration, the aforementioned means may be the TX Processor  368 , the RX Processor  356 , and the controller/processor  359  configured to perform the functions recited by the aforementioned means. 
       FIG. 10  is a diagram  1000  illustrating an example of a hardware implementation for an apparatus  1002 . The apparatus  1002  is a BS and includes a baseband unit  1004 . The baseband unit  1004  may communicate through a cellular RF transceiver with the UE  104 . The baseband unit  1004  may include a computer-readable medium/memory. The baseband unit  1004  is responsible for general processing, including the execution of software stored on the computer-readable medium/memory. The software, when executed by the baseband unit  1004 , causes the baseband unit  1004  to perform the various functions described supra. The computer-readable medium/memory may also be used for storing data that is manipulated by the baseband unit  1004  when executing software. The baseband unit  1004  further includes a reception component  1030 , a communication manager  1032 , and a transmission component  1034 . The communication manager  1032  includes the one or more illustrated components. The components within the communication manager  1032  may be stored in the computer-readable medium/memory and/or configured as hardware within the baseband unit  1004 . The baseband unit  1004  may be a component of the BS  310  and may include the memory  376  and/or at least one of the TX processor  316 , the RX processor  370 , and the controller/processor  375 . 
     The communication manager  1032  includes a temporal filter configuration component  1040  that transmits, to a UE (such as UE  104 ), a temporal filter configuration, e.g., as described in connection with  802  of  FIG. 8 . The communication manager  1032  further includes a CSI value component  1042  that receives, from the UE, a CSI value based on the temporal filter configuration, e.g., as described in connection with  804  of  FIG. 8 . 
     The apparatus may include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of  FIG. 8 . As such, each block in the aforementioned flowchart of  FIG. 8  may be performed by a component and the apparatus may include one or more of those components. The components may be one or more hardware components specifically configured to carry out the stated processes/algorithm, implemented by a processor configured to perform the stated processes/algorithm, stored within a computer-readable medium for implementation by a processor, or some combination thereof. 
     In one configuration, the apparatus  1002 , and in particular the baseband unit  1004 , includes means for transmitting, to a UE, a temporal filter configuration and means for receiving, from the UE, a CSI value based on the temporal filter configuration. The aforementioned means may be one or more of the aforementioned components of the apparatus  1002  configured to perform the functions recited by the aforementioned means. As described supra, the apparatus  1002  may include the TX Processor  316 , the RX Processor  370 , and the controller/processor  375 . As such, in one configuration, the aforementioned means may be the TX Processor  316 , the RX Processor  370 , and the controller/processor  375  configured to perform the functions recited by the aforementioned means. 
     It is understood that the specific order or hierarchy of blocks in the processes/flowcharts disclosed is an illustration of example approaches. Based upon design preferences, it is understood that the specific order or hierarchy of blocks in the processes/flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented. 
     The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Terms such as “if,” “when,” and “while” should be interpreted to mean “under the condition that” rather than imply an immediate temporal relationship or reaction. That is, these phrases, e.g., “when,” do not imply an immediate action in response to or during the occurrence of an action, but simply imply that if a condition is met then an action will occur, but without requiring a specific or immediate time constraint for the action to occur. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof” include any combination of A, B, and/or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C,” “one or more of A, B, or C,” “at least one of A, B, and C,” “one or more of A, B, and C,” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module,” “mechanism,” “element,” “device,” and the like may not be a substitute for the word “means.” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for.” 
     Implementation examples are described in the following numbered clauses. The following examples are illustrative only and may be combined with aspects of other embodiments or teachings described herein, without limitation. 
     1. A method of wireless communication at a user equipment (UE), comprising: receiving, from a base station, a temporal filter configuration; and transmitting, to the base station, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     2. The method of clause 1, wherein whether the UE applies a temporal filter to a CSI measurement to generate the CSI value is based on the temporal filter configuration. 
     3. The method of any of clauses 1-2, wherein the temporal filter configuration identifies a temporal filter and the UE applies the identified temporal filter to a CSI measurement to generate the CSI value. 
     4. The method of any of clauses 1-3, wherein applying the temporal filter comprises generating the CSI value based on the CSI measurement and a previous CSI measurement. 
     5. The method of any of clauses 1-4, wherein the UE is configured with a plurality of temporal filters, the temporal filter configuration identifies a temporal filter of the plurality of temporal filters, and the UE applies the identified temporal filter to a CSI measurement to generate the CSI value. 
     6. The method of any of clauses 1-5, wherein the CSI value is a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. 
     7. The method of any of clauses 1-6, wherein transmitting the CSI value comprises transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     8. The method of any of clauses 1-7, wherein the temporal filter configuration is based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     9. The method of any of clauses 1-8, further comprising receiving, from the base station, a beam selection based on the CSI value. 
     10. The method of any of clauses 1-9, wherein the beam selection is based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and is based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
     11. The method of any of clauses 1-10, wherein transmitting the CSI value comprises transmitting a CSI report, the method further comprising: selecting a beam corresponding to the CSI value from a plurality of beams for inclusion in the CSI report based on the CSI value. 
     12. An apparatus for wireless communication at a user equipment (UE), comprising: a memory; and at least one processor coupled to the memory and configured to: receive, from a base station, a temporal filter configuration; and transmit, to the base station, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     13. The apparatus of clause 12, wherein whether the UE applies a temporal filter to a CSI measurement to generate the CSI value is based on the temporal filter configuration. 
     14. The apparatus of any of clauses 12-13, wherein the temporal filter configuration identifies a temporal filter and the UE applies the identified temporal filter to a CSI measurement to generate the CSI value. 
     15. The apparatus of any of clauses 12-14, wherein applying the temporal filter comprises generating the CSI value based on the CSI measurement and a previous CSI measurement. 
     16. The apparatus of any of clauses 12-15, wherein transmitting the CSI value comprises transmitting a CSI report, the at least one processor being further configured to: select a beam corresponding to the CSI value from a plurality of beams for inclusion in the CSI report based on the CSI value. 
     17. A method of wireless communication at a base station, comprising: transmitting, to a user equipment (UE), a temporal filter configuration; and receiving, from the UE, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     18. The method of clause 17, wherein whether the CSI value is based on a temporal filter is based on the temporal filter configuration. 
     19. The method of any of clauses 17-18, wherein the temporal filter configuration identifies a temporal filter and the CSI value is generated by applying the temporal filter to a CSI measurement. 
     20. The method of any of clauses 17-19, wherein applying the temporal filter comprises generating the CSI value based on the CSI measurement and a previous CSI measurement. 
     21. The method of any of clauses 17-20, wherein the UE is configured with a plurality of temporal filters, the temporal filter configuration identifies a temporal filter of the plurality of temporal filters, and the CSI value is generated by applying the identified temporal filter to a CSI measurement. 
     22. The method of any of clauses 17-21, wherein the CSI value is a signal to noise and interference ratio (SINR) value based on one or more SINR measurement or a reference signal received power (RSRP) value based on one or more RSRP measurement. 
     23. The method of any of clauses 17-22, wherein transmitting the CSI value comprises transmitting a L1-signal to noise and interference ratio (SINR) report or a L1-reference signal received power (RSRP) report. 
     24. The method of any of clauses 17-23, wherein the temporal filter configuration is based on hybrid automatic repeat request (HARQ) reports of the UE, a rate of change in CSI values reported by the UE, a rate of change in channel quality information (CQI) values reported by the UE, or an uplink quality of the UE. 
     25. The method of any of clauses 17-24, further comprising transmitting, to the UE, a beam selection based on the CSI value. 
     26. The method of any of clauses 17-25, wherein the beam selection is based on a first beam selection algorithm if the temporal filter configuration configures the UE to apply a temporal filter to generate the CSI value and is based on a second beam selection algorithm if the temporal filter configuration configures the UE to report a CSI measurement as the CSI value without applying a temporal filter. 
     27. An apparatus for wireless communication at a base station, comprising: a memory; and at least one processor coupled to the memory and configured to: transmit, to a user equipment (UE), a temporal filter configuration; and receive, from the UE, a channel state information (CSI) value, the CSI value being based on the temporal filter configuration. 
     28. The apparatus of clause 27, wherein whether the CSI value is based on a temporal filter is based on the temporal filter configuration. 
     29. The apparatus of any of clauses 27-28, wherein the temporal filter configuration identifies a temporal filter and the CSI value is generated by applying the temporal filter to a CSI measurement. 
     30. The apparatus of any of clauses 27-29, wherein applying the temporal filter comprises generating the CSI value based on the CSI measurement and a previous CSI measurement.