UE null space reporting

Abstract

A configuration for providing UE null space reporting to optimize beam management for multi-UE communications. The apparatus sends, to a base station, a null space report indicating one or more parameters of at least one null space for a UE based on a plurality of antenna elements. The apparatus receives, from the base station, a downlink signal based on the null space report of the UE.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 105,400, filed on November 25, 2020, entitled “UE NULL SPACE REPORT”, which is expressly incorporated herein by reference in its entirety. Technical Field

[0003] In summary, this disclosure relates to communication systems, and more specifically, to configurations for providing user equipment (UE) null space reports to optimize beam management for multi-UE communication. Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services, such as telephone, video, data, messaging, and broadcasting. 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.

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the city, national, regional, and even global levels. An example telecommunications standard is 5G New Radio (NR). 5G NR is part of the Continuous Mobile Broadband Evolution (CMB) initiative released by the 3rd Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., in conjunction with the Internet of Things (IoT),) and other requirements. 5G NR includes services associated with enhanced (pc) mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). Some aspects of 5G NR can be based on the 4G Long Term Evolution (LTE) standard. There is a need for further improvements to 5G NR technology. These improvements can also be applied to other multiple access technologies and telecommunications standards that adopt them. Summary of the Invention

[0006] 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.

[0007] In one aspect of the disclosure, a method, a computer readable medium, and an apparatus are provided. The apparatus can be a device at a UE with multiple antenna elements. The device can be a processor and / or a modem at the UE or the UE itself. The apparatus transmits, to a base station, a null space report based on the multiple antenna elements indicating one or more parameters of at least one null space for the UE. The apparatus receives, from the base station, a downlink signal based on the null space report of the UE.

[0008] In one aspect of the disclosure, a method, a computer readable medium, and an apparatus are provided. The apparatus can be a device at a UE with multiple antenna elements. The device can be a processor and / or a modem at the UE or the UE itself. The apparatus transmits, to a base station, a null space report based on the multiple antenna elements indicating one or more parameters of at least one null space for the UE. The apparatus receives, from the base station, a downlink signal based on the null space report of the UE.

[0009] To the accomplishment of the foregoing and related aspects, one or more aspects comprise the features recited in the following description and the appended claims, and the following description together with the accompanying drawings illustrate and serve to explain the principles of the one or more aspects. Various aspects are described herein in connection with various illustrative features. These features are described or claimed in connection with one or more aspects, but each feature can also be provided independently. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a diagram illustrating an example of a wireless communication system and an access network.

[0011] Figure 2A is a diagram illustrating an example of a first frame, in accordance with various aspects of the present disclosure.

[0012] Figure 2B is a diagram illustrating an example of a DL channel within a subframe, in accordance with various aspects of the present disclosure.

[0013] Figure 2C is a diagram illustrating an example of a second frame, in accordance with various aspects of the present disclosure.

[0014] Figure 2D is a diagram illustrating an example of a UL channel within a subframe, in accordance with various aspects of the present disclosure.

[0015] Figure 3 is a diagram illustrating an example of a base station and a user equipment (UE) in an access network.

[0016] Figure 4A is a diagram illustrating an example of a signal received from a null space perspective in a wireless communication system.

[0017] Figure 4B is a graph illustrating an example of a UE pattern including a null space.

[0018] Figure 5 is a call flow diagram of signaling between a UE and a base station in accordance with certain aspects of the present disclosure.

[0019] Figure 6 is a flow diagram of a method of wireless communication.

[0020] Figure 7 is a diagram illustrating an example of a hardware implementation for an example apparatus.

[0021] Figure 8 is a flow diagram of a method of wireless communication.

[0022] Figure 9 is a diagram illustrating an example of a hardware implementation for an example apparatus. DETAILED DESCRIPTION

[0023] 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 can be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can 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 the concepts being described.

[0024] 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 can be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends on the particular application and design constraints imposed on the overall system.

[0025] By way of example, an element, or any portion of an element, or any combination of elements can 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 can 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.

[0026] Accordingly, in one or more example embodiments, the functions described can be implemented in hardware, software, or any combination thereof. If implemented in software, the functions can 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 can 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), compact disk ROM (CD-ROM), diskette, hard disk drive, memory card, solid-state drive, etc. which computer-readable medium is a tangible computer-readable storage medium.

[0027] Figure 1 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 (WW AN)) 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 can include macro cells (high power cellular base stations) and / or small cells (low power cellular base stations). The macro cells can include base stations. The small cells can include femtocells, picocells, and microcells.

[0028] The base stations 102 configured for 4G LTE (collectively referred to as the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) can 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 the Next Generation RAN (NG-RAN)) can interface with a 5G Core Network (5GC) 190 through second backhaul links 184. In addition to other functions, the base stations 102 can 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 of paging information, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), user and device configuration, user and device tracking, radio resource management (RIM), paging, positioning, and delivery of warning messages. The base stations 102 can communicate directly or indirectly (e.g., through the EPC 160 or 5GC 190) with each other over third backhaul links 134 (e.g., X2 interface). The first, second, and third backhaul links 132, 184, and 134 can be wired or wireless.

[0029] The base stations 102 can wirelessly communicate with the UEs 104. Each of the base stations 102 can provide communication coverage for a respective geographic coverage area 110. There can be overlapping geographic coverage areas 110. For example, a small cell 102' can have a coverage area 110' that overlaps with one or more macro cells 102. A network that includes both small cell and macro cells can be known as a heterogeneous network. A heterogeneous network can also include Home Evolved NodeBs (eNBs) (HeNBs), which can 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 can 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 can use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity. The communication links can be through one or more carriers, and each carrier can be a band of frequency Yx MHz ( x up to 100 MHz (e.g., for mmW), of which up to YThe carriers can be of the same size (e.g., 1.25, 2.5, 5, 10, 15, 20, 40, 60, 80, 100, 200, etc. MHz) or different sizes (e.g., 1.25, 2.5, 5, 10, 15, 20, 40, 60, 80, 100, 200, etc. MHz). The transmission bandwidth can also be divided into subchannels. Each of these subchannels can be of the same size (1.25, 2.5, 5, 10, 15, 20, 40, 60, 80, 100, 200, etc. MHz) or different sizes (e.g., 1.25, 2.5, 5, 10, 15, 20, 40, 60, 80, 100, 200, etc. MHz). The ATs can transmit using some of the subchannels while other subchannels can be unused or can be used for other purposes.

[0030] Certain UEs 104 can communicate with each other using device-to-device (D2D) communication link 158. The D2D communication link 158 can use the DL / UL WWAN spectrum. The D2D communication link 158 can 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 can 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.

[0031] The wireless communications system can also include a Wi-Fi access point (AP) 150 in communication with Wi-Fi stations (STAs) 152 via communication links 154, e.g., in a 5 GHz unlicensed frequency spectrum or the like. When communicating in an unlicensed frequency spectrum, the STAs 152 / AP 150 can perform a clear channel assessment (CCA) prior to communicating in order to determine whether the channel is available.

[0032] The small cells 102' can operate in a licensed and / or an unlicensed spectrum. When operating in an unlicensed spectrum, the small cells 102' can employ NR and use the same unlicensed spectrum as used by the Wi-Fi AP 150 (e.g., 5 GHz). The small cells 102' employing NR in an unlicensed spectrum can boost coverage of the access network and / or increase the capacity of the access network.

[0033] The electromagnetic spectrum is often subdivided based on frequency / wavelength into various classes, bands, channels, etc. In 5G NR, two initial operating bands have been identified as frequency range designations FR1 (410 MHz - 7.125 GHz) and FR2 (24.25 GHz - 52.6 GHz). The frequencies between FR1 and FR2 are often referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to as a “sub-6 GHz” band in various documents and articles. A similar nomenclature issue sometimes occurs with regard to FR2, which is often referred to as a “millimeter wave” band in documents and articles, despite being different from the extremely high frequency (EHF) band (30 GHz - 300 GHz) which is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band.

[0034] With the above aspects in mind, unless specifically stated otherwise, it should be understood that the term “sub-6 GHz” or the like, if used herein, can broadly represent frequencies that can be less than 6 GHz, can be within FR1, or can include mid-band frequencies. Further, unless specifically stated otherwise, it should be understood that the term “millimeter wave” or the like, if used herein, can broadly represent frequencies that can include mid-band frequencies, can be within FR2, or can be within the EHF band.

[0035] A base station 102, whether a small cell 102' or a large cell (e.g., macro base station), can include and / or be referred to as an eNB, gNodeB (gNB), or another type of base station. Some base stations, such as gNB 180 can operate in a traditional sub-6 GHz spectrum, in millimeter wave frequencies, and / or near millimeter wave frequencies in communication with the UE 104. When the gNB 180 operates in millimeter wave frequencies or near millimeter wave frequencies, the gNB 180 can be referred to as a millimeter wave base station. The millimeter wave base station 180 can utilize beamforming 182 with the UE 104 to compensate for the path loss and short range. The base station 180 and the UE 104 can each include a plurality of antennas, such as antenna elements, antenna panels, and / or antenna arrays to facilitate beamforming.

[0036] The base stations 180 can transmit to the UEs 104 in one or more transmit directions 182'. The UEs 104 can receive from the base stations 180 in one or more receive directions 182". The UEs 104 can also transmit to the base stations 180 in one or more transmit directions. The base stations 180 can receive from the UEs 104 in one or more receive directions. The base stations 180 / UEs 104 can perform beam training to determine the best receive and transmit directions for each of the base stations 180 / UEs 104. The transmit and receive directions for the base stations 180 can or can not be the same. The transmit and receive directions for the UEs 104 can or can not be the same.

[0037] The EPC 160 can 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 can 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

[0038] The core network 190 can include an 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 can 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 a IP Services 197. The IP Services 197 can include the Internet, an intranet, an IP Multimedia Subsystem (IMS), a Packet Switched (PS) Streaming (PSS) Service, and / or other IP services.

[0039] A base station can include and / or be referred to as a gNB, NodeB, eNB, access point, base transceiver station, radio base station, radio transceiver, transceiver function, basic service set (BSS), extended service set (ESS), 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 functional device. Some of the UEs 104 can be referred to as IoT devices (e.g., parking meter, gas pump, toaster, vehicle, heart monitor, etc.). The UE 104 can 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 communication 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.

[0040] Referring again to Figure 1 In some aspects, the UE 104 can be configured to provide a null space report to optimize beam management for a multi-UE environment. For example, Figure 1The UE 104 can include a null space component 198 configured to provide a null space report to optimize beam management for multi-UE environments. The UE 104 can transmit, to the base station 180, a null space report indicating one or more parameters of at least one null space for the UE based on a plurality of antenna elements. The UE 104 can receive, from the base station 180, a downlink signal based on the null space report of the UE 104.

[0041] Referring again to Figure 1 In certain aspects, the base station 180 can be configured to optimize multi-UE beam management to allow a base station beam to be directed to a particular UE while in the null space of other UEs. For example, the base station 180 can include a null space component 199 configured to receive, from a UE 104 having a plurality of antenna elements, a null space report indicating one or more parameters of at least one null space for the UE 104 based on the plurality of antenna elements. The base station 180 can receive, from the UE 104 having a plurality of antenna elements, a null space report indicating one or more parameters of at least one null space for the UE 104 based on the plurality of antenna elements. The base station 180 can transmit a downlink signal based on the null space report of the UE 104.

[0042] Although the following description can pertain to 5G NR, the concepts described herein can be applicable to other similar areas, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

[0043] Figure 2A FIG. 2 is a diagram 200 illustrating an example of a first subframe within a 5G NR frame structure. Figure 2B FIG. 3 is a diagram 300 illustrating an example of DL channels within a 5G NR subframe. The 5G NR frame structure can be frequency division duplex (FDD) such that pairs of subcarriers are dedicated for DL or UL transmissions, or can be time division duplex (TDD) such that the same subcarriers are used for both DL and UL transmissions and are divided into multiple resource blocks of subcarriers with a particular duplex direction (DL or UL) at a time. Although a Figure 2C Figure 2D FIG. 4 is a diagram 400 illustrating an example of UL channels within a 5G NR subframe. The 5G NR frame structure can be frequency division duplex (FDD) such that pairs of subcarriers are dedicated for DL or UL transmissions, or can be time division duplex (TDD) such that the same subcarriers are used for both DL and UL transmissions and are divided into multiple resource blocks of subcarriers with a particular duplex direction (DL or UL) at a time. Although a Figure 2A 、 2C ​In the examples provided, a 5G NR frame structure is assumed to be TDD with subframe 4 configured with slot format 28 (with mostly DL), where D is DL, U is UL, and F is flexible to use between DL / UL, and subframe 3 configured with slot format 1 (with all UL). While subframes 3, 4 are shown with slot formats 1, 28, respectively, any particular subframe can be configured with any of the various available slot formats 0-61. Slot formats 0, 1 are all DL, all UL, respectively. Other slot formats 2-61 include a mix of DL, UL, and flexible symbols. A UE is configured with a slot format (dynamically, by DL control information (DCI), or semi-statically / statically, by radio resource control (RRC) signaling) through a received slot format indicator (SFI). Note that the description infra also applies for a 5G NR frame structure that is TDD.

[0044] Other wireless communication technologies can have different frame structures and / or different channels. A frame (10 ms) can be divided into 10 equally sized subframes (1 ms). Each subframe can include one or more slots. A subframe can also include mini-slots, which can contain 7, 4, or 2 symbols. Each slot can contain 7 or 14 symbols, depending on the slot configuration. For slot configuration 0, each slot can contain 14 symbols, while for slot configuration 1, each slot can contain 7 symbols. A symbol on the DL can be a cyclic prefix (CP) orthogonal frequency division multiplexing (OFDM) (CP-OFDM) symbol. A symbol on the UL can be a CP-OFDM symbol (for high throughput scenarios) or a discrete Fourier transform (DFT) spread OFDM (DFT-s-OFDM) symbol (also known as single carrier frequency division multiple access (SC-FDMA) symbol) (for power limited scenarios; limited to single stream transmission). The number of slots within a subframe can be slot configuration and numerology dependent. For slot configuration 0, different numerologies m 0 to 4 allow for 1, 2, 4, 8, and 16 slots per subframe, respectively. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots per subframe, respectively. Accordingly, for slot configuration 0 and numerology m, there are 14 symbols / slot and 2 µ slots / subframe. The subcarrier spacing and symbol length / duration are functions of the numerology. The subcarrier spacing can equal kHz, where is the numerology 0 to 4. Thus, numerology m = 0 has a subcarrier spacing of 15 kHz, and numerology m = 4 has a subcarrier spacing of 240 kHz. The symbol length / duration is inversely related to the subcarrier spacing. Figures 2A-2DAn example is provided of slot configuration 0 (with 14 symbols per slot) and numerology m = 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 ps. Within a frame collection, there can be one or more different bandwidth parts (BWPs) of frequency division multiplexed (see Figure 2B ). Each BWP can have a particular numerology.

[0045] A resource grid can be used to represent the frame structure. Each time slot includes resource blocks (RBs) (also referred to as physical RBs (PRBs)), which are 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.

[0046] As shown in Figure 2A , some of the REs carry reference (pilot) signals (RS) for the UE. The RS can include demodulation RS (DM-RS) (indicated as R for one particular configuration, but other DM-RS configurations are possible) and channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS can also include beam management RS (BRS), beam refinement RS (BRRS), and phase tracking RS (PT-RS).

[0047] Figure 2BExamples of various DL channels within a subframe of a frame are shown. The Physical Downlink Control Channel (PDCCH) carries DCI within one or more Control Channel Elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE comprising six RE Groups (REGs), each REG comprising 12 consecutive REs within an OFDM symbol of an RB. A PDCCH within a BWP can be referred to as a Control Resource Set (CORESET). The UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space) during PDCCH monitoring on a CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs can span the channel bandwidth at larger and / or lower frequencies. The Primary Synchronization Signal (PSS) can be within symbol 2 of a specific subframe of the frame. The PSS is used by UE 104 to determine subframe / symbol timing and physical layer identification. The Secondary Synchronization Signal (SSS) can be within symbol 4 of a specific subframe of the frame. The SSS is used by the UE to determine the Physical Layer Cell Identifier Group Number and radio frame timing. Based on the Physical Layer Identifier and Physical Layer Cell Identifier Group Number, the UE can determine the Physical Cell Identifier (PCI). Based on the PCI, the UE can determine the location of the aforementioned DM-RS. The Physical Broadcast Channel (PBCH), carrying the Master Information Block (MIB), can logically be grouped with the PSS and SSS to form a Synchronization Signal (SS) / PBCH block (also known as an SS block (SSB)). The MIB provides the number of RBs and the System Frame Number (SFN) in the system bandwidth. The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information not transmitted via the PBCH (such as System Information Block (SIB)), and paging messages.

[0048] like Figure 2C As shown, some REs in the REs carry DM-RS for channel estimation at the base station (indicated as R for a specific configuration, but other DM-RS configurations are possible). The UE can transmit DM-RS for the Physical Uplink Control Channel (PUCCH) and DM-RS for the Physical Uplink Shared Channel (PUSCH). PUSCH DM-RS can be transmitted in the first one or two symbols preceding the PUSCH. PUCCH DM-RS can be transmitted in different configurations depending on whether a short or long PUCCH is transmitted and the specific PUCCH format used. The UE can transmit a Sounding Reference Signal (SRS). The SRS can be transmitted in the last symbol of a subframe. The SRS can have a comb structure, and the UE can transmit the SRS on one of the combs. The SRS can be used by the base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

[0049] Figure 2D An example of various UL channels is shown. The PUCCH can be positioned 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) acknowledgment (ACK) (HARQ-ACK) information (ACK / negative ACK (NACK)) feedback. The PUSCH carries data, and can additionally be used to carry buffer status reports (BSRs), power headroom reports (PHRs), and / or UCI.

[0050] Figure 3 FIG. 13 is a diagram of a network in which a base station 310 communicates with a UE 350 in an access network. In the DL, IP packets from the EPC 160 can 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, e.g., 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, e.g., header compression / decompression, security (ciphering, deciphering, integrity protection, integrity verification), and handover support functions; RLC layer functionality associated with, e.g., transfer of upper layer

[0051] 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, can include error detection on the transport channels, forward error correction (FEC) coding / decoding of the transport channels, interleaving, rate matching, mapping to 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 can then be split into parallel streams. Each stream can then be mapped to a 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 can be used to determine the coding and modulation schemes, as well as for spatial processing. The channel estimate can be derived from a reference signal and / or channel condition feedback transmitted by the UE 350. Each spatial stream can then be provided to a different antenna 320 via a separate transmitter 318 TX. Each transmitter 318 TX can modulate an RF carrier with a respective spatial stream for transmission.

[0052] 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 can 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 can 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 can 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.

[0053] The controller / processor 359 can be associated with a memory 360 that stores program codes and data. The memory 360 can 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.

[0054] 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.

[0055] Channel estimates derived by the channel estimator 358 from a reference signal or feedback transmitted by the base station 310 can 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 can be provided to different antenna 352 via separate transmitters 354TX. Each transmitter 354TX can modulate an RF carrier with a respective spatial stream for transmission.

[0056] 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 318RX receives a signal through its respective antenna 320. Each receiver 318RX recovers information modulated onto an RF carrier and provides the information to a RX processor 370.

[0057] The controller / processor 375 can be associated with a memory 376 that stores program codes and data. The memory 376 can 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 can 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.

[0058] At least one of the TX processor 368, the RX processor 356, and the controller / processor 359 can be configured to perform aspects in connection with 198. Figure 1

[0059] At least one of the TX processor 316, the RX processor 370, and the controller / processor 375 can be configured to perform aspects in connection with 199. Figure 1

[0060] In wireless communication systems (e.g., including 5G NR wireless communication systems and other wireless communication systems), reducing power consumption of UEs can be challenging. This challenge can become more prominent as bandwidth grows (e.g., expanding to include bandwidths of frequency ranges (FRs) 4, 5, 6G, etc.). Supporting higher bandwidth signals and increased data rates can result in increased power consumption at the UE.

[0061] As wireless communication systems progress to higher frequency bands (such as, but not limited to, sub-THz), antenna dimensions can decrease due to the antenna size relative to the wavelength. As the size of individual antennas decreases, a UE can include an increased number of antennas in the same size antenna array. The increased number of antenna elements can result in improved spectral efficiency due to an increase in array gain and a decrease in interference. For example, the increased number of antenna elements can enable the UE to transmit and receive using narrower beam widths, which can result in an increased spatial separation between beams.

[0062] An impact of the increased number of antennas is an increase in the null space rank (e.g., the number of null spaces), which increases linearly with the number of antennas. The null space can be intuitively thought of as the angle of arrival that can be nulled due to UE beamforming. For example, a signal transmitted from a null angle of arrival will be faded. For example, refer to Figure 4A ​​FIG. 4 illustrates a diagram 400 including a UE 402, a first transmission reception point (TRP) TRP1 404, and a second TRP TRP2 406. TRP1 404 can transmit a downlink signal 408 to UE 402, and UE 402 receives the downlink signal 408 from TRP1 404 with a UE receive beam 410. TRP2 406 can transmit a downlink signal 412 in a direction 414 toward UE 402. The downlink signal 412 from TRP2 406 can be intended for another UE (not shown), but can be transmitted along a direction 414 that corresponds to a null space of UE 402, such that the downlink signal 412 will not cause interference with UE 402. Due to beamforming at UE 402, the angle of arrival of the downlink signal 412 along direction 414 can be nulled, such that the downlink signal 412 will be faded along direction 414. Figure 4B A graph 450 is shown, which illustrates an example UE pattern that illustrates a null space at different angles of arrival for a UE. A point 420 illustrates a direction or space in which a UE receives a signal. A point 425 illustrates an example null space (e.g., a space between directional beams) in which the UE does not receive a signal or receives a reduced amount of signal as compared to point 420. A UE can have one or more null spaces, where a direction associated with the one or more null spaces can represent a vector of weights that span the null space. The spatial direction corresponding to point 425, as well as other angles with reduced reception, can be referred to as a null space for the UE. TRP2 406 can transmit a signal to a different UE that will arrive at the UE in the null space at point 425 as a way to reduce interference caused to the UE by the signal. The reduction of interference can also be referred to as de- enhancing interference. The number of null spaces at a UE can be based on the number of antennas at the UE. An increase in the number of antennas can correspond to an increase in the rank of the null space. The rank of the null space can be based on the number of antennas and the number of layers after beamforming. For example, the rank of the null space can be determined by the number of antennas minus the number of layers after beamforming.

[0063] In some cases, a spatial-frequency multi-TRP (SFMT) method can use a high rank of null space to transmit a peak-to-average power ratio (PAPR) reduced signal to a UE in a null space of the UE, which can reduce power consumption of the UE. The UE null space can be used to optimize beam management for a multi-UE communication environment. For example, a base station can use one or more null spaces of a UE to transmit a signal to other UEs that can cause interference to the UE. For example, the null space can be used to optimize performance of a UE by directing UE beamforming nulls in interfering side directions.

[0064] Aspects presented herein provide a configuration for providing UE null space reporting to optimize beam management for multi-UE communications. UE null space reporting can assist in reducing power consumption at a UE by reducing the received signal PAPR transmitted from a base station (e.g., TRP). In some aspects, UE null space reporting can assist in improving beam management with multiple UEs or can assist in reducing UE PAPR with SFMT. At least one advantage of the present disclosure is that a base station can utilize UE null reporting to determine the null space of each UE within a multi-UE environment such that interfering beams from the base station can be optimized to transmit within the UE null space. At least another advantage of the present disclosure is that providing information for SFMT to a base station can allow a UE to use a lower resolution analog-to-digital converter (ADC), which can result in a reduction of UE power consumption.

[0065] In some cases, the UE null space reporting can include an angle of arrival of a downlink signal from the base station. Since the UE can move, rotate, etc. without the knowledge of the base station, the angle of arrival information can provide a frame of reference for the base station. The UE null space reporting can include an identification of one or more null spaces of the UE. For example, the one or more null spaces of the UE can be identified based on an angle or other information that identifies a location of the null space. The angle of the null space can be identified based on an antenna element of the UE. Each null space reported can include information about which axis or axes the null space corresponds to in a coordinate system (e.g., Cartesian coordinates, polar coordinates, or any other possible coordinate system). For example, the UE can provide an angle and reference information to the base station. The number of null spaces reported can include a predefined maximum integer of null spaces. The integer can be configured in an RRC message transmitted by the base station to the UE during a connection setup procedure.

[0066] In some cases, the UE null space reporting can include a weight for each antenna phase shifter to identify one or more null spaces of the UE. Providing a weight for each antenna phase shifter can provide the base station with a full beamforming configuration of the UE such that the base station can calculate one or more null spaces of the UE based on the weight for each antenna phase shifter.

[0067] The UE null space reporting can be applied after each beam management refinement procedure performed by the UE. In some cases, the UE can trigger transmission of the null space reporting in the case of changed conditions at the UE. The changed conditions at the UE can include a change in any phase shifter weights used, which can be due to rotation of the UE, physical displacement of the UE, handover to a different base station, etc. The null space reporting can be transmitted by the UE in a channel state information (CSI) report, a medium access control - control element (MAC-CE), or an RRC trigger message.

[0068] In some cases, e.g., when using hybrid beamforming (e.g., analog and digital beamforming), the UE can report the above information for digital and / or analog beamforming. For example, hybrid beamforming can include using analog and digital phase shifters. In such cases, the SFMT can use the reported information to implement PAPR reduction in a hybrid beamforming architecture.

[0069] The base station can be configured to utilize null space reporting. For example, the base station can utilize null space reporting to optimize a multi-UE beam management procedure such that each base station downlink beam can be directed to a particular UE of a multi-UE environment. In such cases, the base station downlink beam can be directed toward or substantially directed toward a null space of other UEs of the multi-UE environment. Directing the base station downlink beam toward the null space of other UEs of the multi-UE environment can reduce or minimize interference experienced by the other UEs from the base station while transmitting downlink signals to the intended UE along the best beam direction. The base station downlink beam can be generated from a set of phase shifters configured to change their weights based on UE null space reports received from other UEs of the multi-UE environment.

[0070] In some cases, the base station can be configured to utilize null space reporting to utilize SFMT to reduce UE PAPR. Base station reducing UE PAPR can result in a reduction in power consumption at the UE caused by UE ADCs, filters, beamforming, etc.

[0071] Figure 5 FIG. 5 is a call flow diagram 500 of signaling between a UE 502 and a base station 504. The base station 504 can be configured to provide at least one cell. The UE 502 can be configured to communicate with the base station 504. For example, in the context of FIG. 1, the base station 504 can correspond to the base station 102 / 180 and the UE 502 can correspond to at least the UE 104. In another example, in the context of FIG. 3, the base station 504 can correspond to the base station 310 and the UE 502 can correspond to the UE 350. Optional aspects are shown with dashed lines. Figure 1 In the context of FIG. 1, the base station 504 can correspond to the base station 102 / 180 and accordingly, the cell can include the geographic coverage area 110 in which communication coverage is provided and / or the small cell 102’ having the coverage area 110’. Further, the UE 502 can correspond to at least the UE 104. In another example, in the context of FIG. 3, the base station 504 can correspond to the base station 310 and the UE 502 can correspond to the UE 350. Figure 3 In the context of FIG. 1, the base station 504 can correspond to the base station 102 / 180 and accordingly, the cell can include the geographic coverage area 110 in which communication coverage is provided and / or the small cell 102’ having the coverage area 110’. Further, the UE 502 can correspond to at least the UE 104. In another example, in the context of FIG. 3, the base station 504 can correspond to the base station 310 and the UE 502 can correspond to the UE 350. Optional aspects are shown with dashed lines.

[0072] In some aspects, for example, as shown at 506, base station 504 can send a configuration of an integer. Base station 504 can send the configuration of the integer during the connection establishment process with UE 502. UE 502 can receive this configuration from base station 504. Base station 504 can also send the configuration of the integer in an RRC message during the connection establishment process. This integer can correspond to an integer number of null spaces in UE 502.

[0073] As shown at 508, UE 502 may send a null space report indicating one or more parameters for at least one null space of UE 502. In some aspects, UE 502 may include multiple antenna elements. UE 502 may send the null space report to base station 504. Base station 504 may receive the null space report from UE 502. The null space report indicating one or more parameters for at least one null space of UE 502 may be based on multiple antenna elements. In some aspects, the null space report may include the angle of arrival for a downlink signal from base station 504. In some aspects, one or more parameters of the null space report may include the angle of each null space of UE 502. In some aspects, the null space report may indicate one or more parameters for a subset of null spaces of UE 502. This subset may correspond to a maximum number of null spaces, for example, and this maximum number may be a defined number or may be configured for the UE. The subset of null spaces may include an integer number of null spaces. In some aspects, the null space report may include information indicating the corresponding axis or coordinate on which one or more parameters of the null space report are based. In some aspects, one or more parameters of the zero-space report may include one or more zero-space weights for one or more antenna phase shifters of UE 502. Each zero space of UE 502 may be determined based on one or more zero-space weights used by one or more antenna phase shifters. In some aspects, the transmission of a zero-space report may be triggered by a change in one or more zero-space weights for one or more antenna phase shifters of UE 502. In some aspects, when using hybrid beamforming, one or more parameters of the zero-space report may include parameters related to digital or analog beamforming.

[0074] In some aspects, for example, as shown at 510, the base station 504 can utilize zero space reporting to optimize a multi-UE beam management procedure for a plurality of UEs including the UE 502. The zero space reporting can allow the base station 504 to optimize a multi-UE beam management procedure for a plurality of UEs including the UE 502 such that a downlink signal directed to one of the plurality of UEs (e.g., 502) is in a zero space of other UEs of the plurality of UEs. Transmitting the downlink signal within the zero space of the other UEs can minimize interference from the base station 504 at the other UEs. In some aspects, the downlink signal can be based on a set of phase shifters that change weights based on the zero space report from the other UEs of the plurality of UEs.

[0075] In some aspects, for example, as shown at 512, the UE 502 can conduct a beam management refinement procedure in response to a changed condition of the UE 502. Transmission of the zero space report can be triggered by the beam management refinement procedure. In some aspects, the changed condition of the UE 502 can include at least one of a rotation of the UE 502, a physical displacement of the UE 502, or a handover to a different base station. The changed condition can relate to a different transmit beam and / or a different antenna panel being used to communicate with the base station 504. In some aspects, transmission of the zero space report can be triggered by the UE 502 in response to the changed condition of the UE 502. In some aspects, the UE 502 can transmit an updated zero space report to reflect the changed condition of the UE 502.

[0076] In some aspects, for example, as shown at 514, the base station 504 can transmit an indication indicating a location of one or more other base stations. The base station 504 can transmit, to the UE 502, an indication indicating a location of one or more other base stations. The UE 502 can receive the indication from the base station 504. The indication can instruct the UE 502 to position a null in a direction of the one or more other base stations such that transmissions from the one or more other base stations can be directed toward the null of the UE 502, which can minimize interference at the UE 502 from the one or more other base stations. In some aspects, the UE 502 can utilize the location of the one or more other base stations to optimize beamforming or minimize interference from the one or more other base stations.

[0077] In some aspects, the UE 502 can position at least one null space of the UE 502 toward a location of one or more other base stations, as shown, for example, at 516. The UE 502 can position at least one null space of the UE 502 toward a location of one or more other base stations such that transmissions from the one or more other base stations can be directed toward the at least one null space of the UE 502, which can minimize interference at the UE 502 from the one or more other base stations. For example, the indication of the location of the one or more other base stations received from the base station 504 can include an elevation and an azimuth of the other base stations compared to an angle of arrival. The UE 502 can direct its null based on the parameters or coordinates provided in the indication by estimating the angle of arrival and including the elevation and azimuth at the corresponding direction.

[0078] As shown at 518, the base station 504 can transmit a downlink signal based on the null space report of the UE 502. The base station 504 can transmit a downlink signal to the UE 502. The UE 502 can receive the downlink signal from the base station 504. In some aspects, the downlink signal can include a peak-to-average power ratio (PAPR) reduction signal based on the null space report received from the UE 502.

[0079] Figure 6 FIG. 6 is a flow diagram of a method of wireless communication. The method can be performed by a UE or a component of a UE (e.g., the UE 104; the apparatus 702; the cellular baseband processor 704, which can include the memory 360 and which can be the entire UE 350 or a component of the UE 350, such as the TX processor 368, the RX processor 356, and / or the controller / processor 359). One or more of the illustrated operations can be omitted, transposed, or combined. Alternative aspects are illustrated with dashed lines. The method can allow the UE to provide a null space report to optimize beam management for a multi-UE environment.

[0080] In some aspects, the UE can receive a configuration of an integer, as shown, for example, at 602. For example, 602 can be performed by the configuration component 740 of the apparatus 702. The UE can receive the configuration of the integer during a connection setup procedure with a base station. The UE can receive the configuration of the integer in an RRC message during the connection setup procedure. The integer can correspond to an integer number of null spaces of the UE. Figure 5 An example is shown in which the UE 502 receives a configuration 506 of an integer (e.g., of a null space) from the base station 504.

[0081] At 604, the UE with multiple antenna elements can transmit a null-space report indicating one or more parameters for at least one null-space of the UE. A null-space can include an area between directional beams where the UE does not receive a signal or receives a reduced amount of a signal. The UE can have one or more null-spaces, where a direction associated with the one or more null-spaces can represent a vector of weights across the null-space. In some examples, the report or message providing the parameters can be referred to by a different name than the “null-space report.” For example, 604 can be performed by the null-space component 742 of the apparatus 702. Figure 5 An example is shown in which the UE 502 transmits a null-space report 508 to the base station 504. The UE can transmit a null-space report to the base station. The null-space report can indicate one or more parameters for at least one null-space of the UE can be based on the multiple antenna elements. In some aspects, the null-space report can include an angle of arrival for a downlink signal from the base station. In some aspects, the one or more parameters of the null-space report can include an angle of each null-space of the UE. In some aspects, the null-space report can indicate one or more parameters for a subset of null-spaces of the UE. The subset can correspond to a maximum number of null-spaces, for example, and the maximum number can be a defined number or can be configured for the UE. The subset of null-spaces can include an integer number of null-spaces. In some aspects, the null-space report can include information indicating a corresponding axis or coordinate on which the one or more parameters of the null-space report are based. In some aspects, the one or more parameters of the null-space report can include one or more null-space weights for one or more antenna phase shifters of the UE. Each null-space of the UE can be determined based on the one or more null-space weights used by the one or more antenna phase shifters. In some aspects, the transmission of the null-space report can be triggered by a change in the one or more null-space weights for the one or more antenna phase shifters of the UE. In some aspects, when hybrid beamforming is utilized, the one or more parameters of the null-space report can include parameters related to digital or analog beamforming.

[0082] In some aspects, for example at 606, the UE can conduct a beam management refinement procedure in response to a changed condition of the UE. For example, 606 can be performed by the beam management component 744 of the apparatus 702. Figure 5 An example is shown in which the UE 502 conducts a beam management refinement procedure at 512. The transmission of the null-space report can be triggered by the beam management refinement procedure. In some aspects, the changed condition of the UE can include at least one of a rotation of the UE, a physical displacement of the UE, or a handover to a different base station. The changed condition can relate to a different transmit beam and / or a different antenna panel being used to communicate with the base station. In some aspects, the transmission of the null-space report can be triggered by the UE in response to the changed condition of the UE.

[0083] In some aspects, the UE can receive an indication indicating a location of one or more other base stations, for example, at 608. For example, 608 can be performed by the indication component 746 of the apparatus 702. Figure 5 An example is shown in which the UE 502 receives such an indication 514 from the base station 504. The UE can receive the indication from the base station. The UE can utilize the location of the one or more other base stations to optimize beamforming or to minimize interference from the one or more other base stations.

[0084] In some aspects, the UE can position at least one null space of the UE toward a location of one or more other base stations, for example, at 610. For example, 610 can be performed by the positioning component 748 of the apparatus 702. Figure 5 An example is shown in which the UE 502 positions at least one null space of the UE toward a location of the other base station. The UE can position at least one null space of the UE toward the location of the one or more other base stations such that transmissions from the one or more other base stations can be directed toward the at least one null space of the UE, which can minimize interference from the one or more other base stations.

[0085] At 612, the UE can receive a downlink signal based on the null space report of the UE. For example, 612 can be performed by the DL signal component 750 of the apparatus 702. The UE can receive the downlink signal based on the null space report from the base station. Figure 5 An example is shown in which the UE 502 receives a downlink signal 518 based on the null space report from the base station 504. For example, the downlink signal 518 can be generated by the base station based on one or more parameters for the at least one null space of the UE. The UE can provide the one or more parameters to the base station in the null space report. Providing such parameters for the at least one null space of the UE to the base station can assist the base station in optimizing transmission of the downlink signal to the UE.

[0086] Figure 7is a diagram 700 illustrating an example of a hardware implementation for an apparatus 702. The apparatus 702 is a UE and includes a cellular baseband processor 704 (also referred to as a modem) coupled with a cellular RF transceiver 722 and one or more Subscriber Identity Modules (SIM) cards 720, an application processor 706 coupled with a secure digital (SD) card 708 and a screen 710, a Bluetooth module 712, a wireless local area network (WLAN) module 714, a Global Positioning System (GPS) module 716, and a power supply 718. The cellular baseband processor 704 communicates with the UE 104 and / or BS 102 / 180 by way of the cellular RF transceiver 722. The cellular baseband processor 704 can include a computer-readable medium / memory. The computer-readable medium / memory can be non-transitory. The cellular baseband processor 704 is Figure 3 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 704, causes the cellular baseband processor 704 to perform the various functions described supra. The computer-readable medium / memory can also be used for storing data that is manipulated by the cellular baseband processor 704 when executing software. The cellular baseband processor 704 further includes a reception component 730, a communication manager 732, and a transmission component 734. The communication manager 732 includes the one or more illustrated components. The components of the communication manager 732 can be stored in the computer-readable medium / memory and / or configured as hardware within the cellular baseband processor 704. The cellular baseband processor 704 can be a component of the UE 350 and can include at least one of the TX processor 368, the RX processor 356, and the controller / processor 359 and / or the memory 360. In one configuration, the apparatus 702 can be a modem chip and include only the cellular baseband processor 704, and in another configuration, the apparatus 702 can be an entire UE (e.g., see 350) and include the above-described additional modules of the apparatus 702.

[0087] The communication manager 732 includes a configuration component 740 that can receive a configuration of an integer, e.g., as described in connection with 602 of Figure 6 The communication manager 732 further includes a null space component 742 that is configured to transmit a null space report indicating one or more parameters of at least one null space for the UE, e.g., as described in connection with 604 of Figure 6 The communication manager 732 further includes a beam management component 744 that is configured to conduct a beam management refinement procedure in response to a changed condition of the UE, e.g., as described in connection with 606 of Figure 6 The communication manager 732 further includes an indication component 746 that is configured to receive an indication of a location of one or more other base stations, e.g., as described in connection with 608 of Figure 6As described in 608. The communication manager 732 also includes a placement component 748 configured to place at least one null space of the UE toward one or more other base stations, for example, as in combination with Figure 6 As described in 610. The communication manager 732 also includes a DL signaling component 750, which is configured to receive downlink signals based on the UE's null space report, for example, as in conjunction with... Figure 6 As described in 612.

[0088] The device may include the ability to perform the above-described actions. Figure 6 The flowchart shows the algorithm's additional components in each box. Therefore, the above... Figure 6 Each box in the flowchart can be executed by a component, and the apparatus can include one or more of these components. These components can be one or more hardware components specifically configured to execute the process / algorithm, implemented by a processor configured to execute the process / algorithm, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

[0089] In one configuration, apparatus 702 (and specifically, cellular baseband processor 704) includes: a unit for transmitting a null space report to a base station, the null space report indicating one or more parameters for at least one null space of the UE based on a plurality of antenna elements. The apparatus includes: a unit for receiving downlink signals from the base station based on the UE's null space report. The apparatus further includes: a unit for receiving configurations for integers in an RRC message during connection establishment with the base station. The apparatus further includes: a unit for performing a beam management refinement process in response to changing conditions of the UE. The transmission of the null space report is triggered by the beam management refinement process. The apparatus further includes: a unit for receiving an indication from the base station of the location of one or more other base stations. The apparatus further includes: a unit for positioning at least one null space of the UE toward the location of one or more other base stations. The aforementioned units may be one or more of the components of apparatus 702 configured to perform the functions described therein. As described above, apparatus 702 may include a TX processor 368, an RX processor 356, and a controller / processor 359. Therefore, in one configuration, the aforementioned units may be TX processor 368, RX processor 356, and controller / processor 359, which are configured to perform the functions described in the aforementioned units.

[0090] Figure 8is a flowchart 800 of a method of wireless communication. The method can be performed by a base station or a component of a base station (e.g., the base station 102 / 180; the apparatus 902; the baseband unit 904, which can include the memory 376 and which can be the entire base station 310 or a component of the base station 310, such as the TX processor 316, the RX processor 370, and / or the controller / processor 375). One or more of the illustrated operations can be omitted, transposed, or combined. Optional aspects are indicated by a dashed line. The method can allow a base station to optimize multi-UE beam management to allow a base station beam to be directed to a particular UE while in the null space of other UEs.

[0091] In some aspects, the base station can transmit a configuration of the integer, for example, at 802. For example, 802 can be performed by the configuration component 940 of the apparatus 902. The base station can transmit the configuration of the integer during a connection setup procedure with the UE. The base station can transmit the configuration of the integer in an RRC message during the connection setup procedure. The integer can correspond to an integer number of null spaces of the UE. Figure 5 An example is shown in which the base station 504 transmits a configuration 506 of an integer (e.g., of a null space) to the UE 502.

[0092] At 804, the base station can receive a null space report indicating one or more parameters of at least one null space for the UE. For example, 804 can be performed by the null space component 942 of the apparatus 902. Figure 5 An example is shown in which the base station 504 receives a null space report 508 from the UE 502. The base station can receive the null space report from a UE having a plurality of antenna elements. The null space report indicating one or more parameters of at least one null space for the UE can be based on the plurality of antenna elements. In some aspects, the null space report can include angles of arrival for downlink signals from the base station. In some aspects, the one or more parameters of the null space report can include an angle of each null space of the UE. In some aspects, the null space report can indicate one or more parameters of a subset of null spaces for the UE. The subset can correspond to a maximum number of null spaces, for example, and the maximum number can be a defined number or can be configured for the UE. The subset of null spaces can include an integer number of null spaces. In some aspects, the null space report can include information indicating corresponding axes or coordinates on which the one or more parameters of the null space report are based. In some aspects, the one or more parameters of the null space report can include one or more null space weights for one or more antenna phase shifters of the UE. Each null space of the UE can be determined based on the one or more null space weights used by the one or more antenna phase shifters. In some aspects, when hybrid beamforming is utilized, the one or more parameters of the null space report can include parameters related to digital or analog beamforming.

[0093] In some aspects, the base station can optimize a multi-UE beam management procedure for a plurality of UEs including the UE with zero space reporting, for example at 806. For example, 806 can be performed by the beam management component 944 of the apparatus 902. Figure 5 An example is shown in which the base station 504 optimizes a multi-UE beam management procedure at 510. The zero space reporting can allow the base station to optimize a multi-UE beam management procedure for a plurality of UEs including the UE such that a downlink signal directed to one of the plurality of UEs is in a null space of other UEs of the plurality of UEs. Transmitting the downlink signal within the null space of the other UEs can minimize interference from the base station at the other UEs. In some aspects, the downlink signal can be based on a set of phase shifters that change weights based on the zero space report from the other UEs of the plurality of UEs.

[0094] In some aspects, the base station can transmit an indication indicating a location of one or more other base stations, for example at 808. For example, 808 can be performed by the indication component 946 of the apparatus 902. Figure 5 An example is shown in which the base station 504 transmits such an indication 514 to the UE 502. The indication can instruct the UE to position a null in the direction of the one or more other base stations such that transmissions from the one or more other base stations can be directed toward the null of the UE, which can minimize interference at the UE from the one or more other base stations.

[0095] At 810, the base station can transmit a downlink signal based on the null space report of the UE. For example, 810 can be performed by the DL signal component 948 of the apparatus 902. Figure 5 An example is shown in which the base station 504 transmits a downlink signal 518 to the UE 502 based on the null space report. The base station can transmit a downlink signal to the UE. In some aspects, the downlink signal can include a PAPR reduced signal based on the null space report received from the UE. For example, the downlink signal 518 can be generated by the base station based on one or more parameters of at least one null space for the UE. The UE can provide the one or more parameters to the base station in the null space report. Providing such parameters of at least one null space for the UE to the base station can assist the base station in optimizing transmission of a downlink signal to the UE.

[0096] Figure 9is a diagram 900 illustrating an example of a hardware implementation for an apparatus 902. The apparatus 902 is a BS and includes a baseband unit 904. The baseband unit 904 can communicate through a cellular RF transceiver with the UE 104. The baseband unit 904 can include a computer- readable medium / memory. The baseband unit 904 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 904, causes the baseband unit 904 to perform the various functions described supra. The computer-readable medium / memory can also be used for storing data that is manipulated by the baseband unit 904 when executing software. The baseband unit 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 of the communication manager 932 can be stored in the computer-readable medium / memory and / or configured as hardware within the baseband unit 904. The baseband unit 904 can be a component of the BS 310 and can include at least one of the TX processor 316, the RX processor 370, and the controller / processor 375, and / or the memory 376.

[0097] The communication manager 932 includes a configuration component 940, which can transmit a configuration of an integer, e.g., as described in connection with 802 of Figure 8 The communication manager 932 further includes a null space component 942, which can receive a null space report indicating one or more parameters of at least one null space for a UE, e.g., as described in connection with 804 of Figure 8 The communication manager 932 further includes a beam management component 944, which can utilize the null space report to optimize a multi-UE beam management procedure for a plurality of UEs including the UE, e.g., as described in connection with 806 of Figure 8 The communication manager 932 further includes an indication component 946, which can transmit an indication indicating locations of one or more other base stations, e.g., as described in connection with 808 of Figure 8 The communication manager 932 further includes a DL signal component 948, which can transmit a downlink signal based on the null space report of the UE, e.g., as described in connection with 810 of Figure 8

[0098] The apparatus can include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of FIG. 10. As such, each block in the aforementioned flowcharts of FIG. 10 can be performed by a component and the apparatus can include one or more of those components. The components can 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. Figure 8 Figure 8 The apparatus can include additional components that perform each of the blocks of the algorithm in the aforementioned flowchart of FIG. 10. As such, each block in the aforementioned flowcharts of FIG. 10 can be performed by a component and the apparatus can include one or more of those components. The components can 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. ​​

[0099] In one configuration, the apparatus 902 (and in particular, the baseband unit 904) includes means for receiving a null space report from a UE having a plurality of antenna elements, the null space report indicating one or more parameters of at least one null space for the UE based on the plurality of antenna elements. The apparatus includes means for transmitting a downlink signal based on the null space report of the UE. The apparatus further includes means for transmitting a configuration of an integer in a RRC message during connection setup with the UE. The apparatus further includes means for utilizing the null space report to optimize a multi-UE beam management procedure for a plurality of UEs including the UE such that a downlink signal directed to one UE of the plurality of UEs is in a null space of other UEs of the plurality of UEs. The apparatus further includes means for transmitting an indication to the UE indicating locations of one or more other base stations, where the indication instructs the UE to position a null in a direction of the one or more other base stations. The aforementioned means can be one or more of the aforementioned components of the apparatus 902 configured to perform the functions recited by the aforementioned means. As described above, the apparatus 902 can include the TX processor 316, the RX processor 370, and the controller / processor 375. As such, in one configuration, the aforementioned means can be the TX processor 316, the RX processor 370, and the controller / processor 375 configured to perform the functions recited by the aforementioned means.

[0100] It should be understood that the specific order or hierarchy of steps in the processes / flow diagrams disclosed is an illustration. Based upon design choices, the specific order or hierarchy of steps in the processes / flow diagrams can be re-arranged. Furthermore, some steps can be optional. The accompanying method claims present elements of the various steps in the order in which they are presented in the processes / flow diagrams. The method claims should not be construed as necessarily limited to the particular order or hierarchy presented.

[0101] The following examples are illustrative only and can be combined with other embodiments or teachings described herein without limitation.

[0102] Aspect 1 is a method of wireless communication at a UE having a plurality of antenna elements, comprising: transmitting, to a base station, a null space report based on the plurality of antenna elements, the null space report indicating one or more parameters of at least one null space for the UE; and receiving, from the base station, a downlink signal based on the null space report of the UE.

[0103] In Aspect 2, the method of Aspect 1 further includes that the null space report includes an angle of arrival for the downlink signal from the base station.

[0104] In Aspect 3, the method of Aspect 1 or 2 further includes that the one or more parameters of the null space report include an angle of each null space of the UE.

[0105] In Aspect 4, the method of any of Aspects 1-3 further includes that the null space report indicates the one or more parameters for a subset of null spaces for the UE.

[0106] In Aspect 5, the method of any of Aspects 1-4 further includes that the subset of null spaces includes an integer number of null spaces, the method further comprising receiving a configuration of the integer in a radio resource control (RRC) message during connection setup with the base station.

[0107] In Aspect 6, the method of any of Aspects 1-5 further includes that the null space report includes information indicating corresponding axes or coordinates on which the one or more parameters of the null space report are based.

[0108] In Aspect 7, the method of any of Aspects 1-6 further includes that the one or more parameters of the null space report include one or more null space weights for one or more antenna phase shifters of the UE, wherein each null space of the UE is determined based on the one or more null space weights used by the one or more antenna phase shifters.

[0109] In Aspect 8, the method of any of Aspects 1-7 further includes conducting a beam management refinement procedure in response to a changed condition of the UE, wherein the transmission of the null space report is triggered by the beam management refinement procedure.

[0110] In Aspect 9, the method of any of Aspects 1-8 further includes that the changed condition of the UE includes a rotation of the UE, a physical displacement of the UE, or a handover to a different base station.

[0111] In Aspect 10, the method of any of Aspects 1-9 further includes that the transmission of the null space report is triggered by the UE in response to the changed condition of the UE.

[0112] In Aspect 11, the method of any of Aspects 1-10 further includes that the transmission of the null space report is triggered by a change of one or more null space weights for one or more antenna phase shifters of the UE.

[0113] In Aspect 12, the method of any of Aspects 1-11 further includes that the one or more parameters of the null space report include parameters related to digital or analog beamforming when hybrid beamforming is utilized.

[0114] In Aspect 13, the method of any of Aspects 1-12 further includes receiving, from the base station, an indication indicating a location of one or more other base stations, and positioning the at least one null space of the UE toward the location of the one or more other base stations.

[0115] Aspect 14 is an apparatus comprising one or more processors and one or more memories storing instructions in electronic communication with the one or more processors, the instructions being executable by the one or more processors to cause a system or device to implement the method of any of Aspects 1-13.

[0116] Aspect 15 is a system or device comprising means for implementing the method of any of Aspects 1-13 or means for implementing the apparatus of any of Aspects 1-13.

[0117] Aspect 16 is a non-transitory computer-readable medium storing instructions executable by one or more processors to cause the one or more processors to implement the method of any of Aspects 1-13.

[0118] Aspect 17 is a method of wireless communication at a base station, comprising: receiving, from a UE having a plurality of antenna elements, a null space report based on the plurality of antenna elements, the null space report indicating one or more parameters of at least one null space for the UE, and transmitting a downlink signal based on the null space report of the UE.

[0119] In Aspect 18, the method of Aspect 17 further includes that the null space report includes an angle of arrival for the downlink signal from the base station.

[0120] In Aspect 19, the method of Aspect 17 or 18 further includes that the one or more parameters of the null space report include an angle of each null space of the UE.

[0121] In Aspect 20, the method of any of Aspects 17-19 further includes that the null space report indicates the one or more parameters for a subset of null spaces of the UE.

[0122] In Aspect 21, the method of any of Aspects 17-20 further includes that the subset of null spaces includes an integer number of null spaces, the method further including transmitting a configuration of the integer number in a RRC message during connection setup with the base station.

[0123] In Aspect 22, the method of any of Aspects 17-21 further includes that the null space report includes information indicating a corresponding axis or coordinate on which the one or more parameters of the null space report are based.

[0124] In Aspect 23, the method of any of Aspects 17-22 further includes that the one or more parameters of the null space report include one or more null space weights for one or more antenna phase shifters of the UE, wherein each null space of the UE is determined based on the one or more null space weights used by the one or more antenna phase shifters.

[0125] In Aspect 24, the method of any of Aspects 17-23 further includes utilizing the null space report to optimize a multi-UE beam management procedure for a plurality of UEs including the UE such that the downlink signal directed to one UE of the plurality of UEs is in a null space of other UEs of the plurality of UEs.

[0126] In Aspect 25, the method of any of Aspects 17-24 further includes that the downlink signal is based on a set of phase shifters that change weights based on null space reports from other UEs of the plurality of UEs.

[0127] In Aspect 26, the method of any of Aspects 17-25 further includes that the downlink signal is a PAPR reduction signal based on the null space report received from the UE.

[0128] In Aspect 27, the method of any of Aspects 17-26 further includes that the one or more parameters of the null space report include parameters related to digital or analog beamforming when utilizing hybrid beamforming.

[0129] In Aspect 28, the method of any of Aspects 17-27 further includes transmitting an indication to the UE indicating locations of one or more other base stations, wherein the indication instructs the UE to position nulls in directions of the one or more other base stations.

[0130] Aspect 29 is an apparatus comprising one or more processors and one or more memories storing instructions that are executable by the one or more processors to cause a system or device to implement a method as in any of Aspects 17-28.

[0131] Aspect 30 is a system or device comprising means for implementing a method or realizing an apparatus as in any of Aspects 17-28.

[0132] Aspect 31 is a non-transitory computer-readable medium storing instructions executable by one or more processors to cause the one or more processors to implement a method as in any of aspects 17-28.

[0133] The preceding 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 can 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 conveying an immediate time relationship or reaction. That is, these phrases, e.g., "when" statements are not intended to mean that the subsequent action will happen immediately or be contingent on the preceding action, but rather that the subsequent action will happen at some time in the future, not necessarily immediately, and / or the preceding action is simply a condition for the occurrence of the subsequent action. 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 the group consisting of A, B, and C," "one or more of the group consisting of A, B, and C," and the like encompasses the combination of A alone, B alone, C alone, A and B together, A and C together, B and C together, or A and B and C together. Specifically, the combination "at least one of A, B, or C" encompasses the combinations of A alone, B alone, C alone, A and B together, A and C together, B and C together, or A and B and C together. The term "plurality" refers to a set of two or more. The term "group" refers to a set of one or more. 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 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 can 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."

Claims

1. A method for wireless communication at a user equipment (UE) having multiple antenna elements, comprising: Sending a null space report to the base station indicating one or more parameters for at least one null space of the UE, wherein the null space report sent by the UE to the base station indicates the one or more parameters of the at least one null space based on the plurality of antenna elements of the UE and including the angle of arrival for the downlink signal from the base station and the angle of each null space of the UE; and The downlink signal is received from the base station based on the null space report of the UE.

2. The method according to claim 1, wherein, The zero-space report indicates one or more parameters for a subset of the zero space of the UE.

3. The method according to claim 2, wherein, The subset of the null space comprises an integer number of null spaces, and the method further includes: During the connection establishment with the base station, the configuration of the integer is received in a Radio Resource Control (RRC) message.

4. The method according to claim 1, wherein, The null space report includes information indicating the corresponding axis or coordinates on which the one or more parameters of the null space report are based.

5. The method according to claim 1, wherein, The one or more parameters of the zero-space report include one or more zero-space weights for one or more antenna phase shifters of the UE, wherein each zero space of the UE is determined based on the one or more zero-space weights used by the one or more antenna phase shifters.

6. The method according to claim 1, further comprising: The beam management refinement process is performed in response to changes in the conditions of the UE, wherein the transmission of the null space report is triggered by the beam management refinement process.

7. The method according to claim 6, wherein, The conditions for the change of the UE include rotation of the UE, physical displacement of the UE, or handover to a different base station.

8. The method according to claim 6, wherein, The transmission of the zero-space report is triggered by the UE in response to the changed conditions of the UE.

9. The method according to claim 1, wherein, The transmission of the zero-space report is triggered by a change in one or more zero-space weights of one or more antenna phase shifters used by the UE.

10. The method according to claim 1, wherein, When using hybrid beamforming, the one or more parameters reported by the zero space include parameters related to digital or analog beamforming.

11. The method according to claim 1, further comprising: Receive from the base station an indication of the location of one or more other base stations; as well as The UE is positioned at least one null space toward the location of the one or more other base stations.

12. An apparatus for wireless communication at a user equipment (UE) having a plurality of antenna elements, comprising: Memory; as well as At least one processor, coupled to the memory, is configured to: A null space report is sent to the base station indicating one or more parameters for at least one null space of the UE, wherein the null space report sent by the UE to the base station indicates the one or more parameters of the at least one null space based on the plurality of antenna elements of the UE and includes the angle of arrival for the downlink signal from the base station and the angle of each null space of the UE; as well as The downlink signal is received from the base station based on the null space report of the UE.

13. The apparatus according to claim 12, wherein, The at least one processor is configured to: The beam management refinement process is performed in response to changes in the conditions of the UE, wherein the transmission of the null space report is triggered by the beam management refinement process.

14. The apparatus according to claim 12, wherein, The at least one processor is configured to: Receive from the base station an indication of the location of one or more other base stations; and The UE is positioned at least one null space toward the location of the one or more other base stations.

15. A method for conducting wireless communication at a base station, comprising: A null space report is received from a UE having multiple antenna elements, indicating one or more parameters for at least one null space of the UE, wherein the null space report sent by the UE to the base station indicates the one or more parameters of the at least one null space based on the multiple antenna elements of the UE and includes the angle of arrival for the downlink signal from the base station and the angle of each null space of the UE; and The downlink signal is transmitted based on the UE's null space report.

16. The method according to claim 15, wherein, The zero-space report indicates one or more parameters for a subset of the zero space of the UE.

17. The method according to claim 16, wherein, The subset of the null space comprises an integer number of null spaces, and the method further includes: The configuration of the integer is sent in a Radio Resource Control (RRC) message during the connection establishment with the UE.

18. The method according to claim 15, wherein, The null space report includes information indicating the corresponding axis or coordinates on which the one or more parameters of the null space report are based.

19. The method according to claim 15, wherein, The one or more parameters of the zero-space report include one or more zero-space weights for one or more antenna phase shifters of the UE, wherein each zero space of the UE is determined based on the one or more zero-space weights used by the one or more antenna phase shifters.

20. The method of claim 15, further comprising: The null space report is used to optimize the multi-UE beam management process for multiple UEs including the UE, such that the downlink signal directed to one of the multiple UEs is in the null space of the other UEs.

21. The method according to claim 20, wherein, The downlink signal is based on a set of phase shifters, which adjusts weights based on null space reports from the other UEs among the plurality of UEs.

22. The method according to claim 15, wherein, The downlink signal is based on the reduced peak-to-average power ratio (PAPR) signal reported by the null space received from the UE.

23. The method according to claim 15, wherein, When using hybrid beamforming, the one or more parameters reported by the zero space include parameters related to digital or analog beamforming.

24. The method of claim 15, further comprising: Send an instruction to the UE indicating the location of one or more other base stations, wherein the instruction instructs the UE to place a zero position in the direction of the one or more other base stations.

25. An apparatus for conducting wireless communication at a base station, comprising: Memory; as well as At least one processor, coupled to the memory, is configured to: A null space report is received from a UE having multiple antenna elements, indicating one or more parameters for at least one null space of the UE, wherein the null space report sent by the UE to the base station indicates the one or more parameters of the at least one null space based on the multiple antenna elements of the UE and includes the angle of arrival for downlink signals from the base station and the angle of each null space of the UE; as well as The downlink signal is transmitted based on the UE's null space report.

26. The apparatus according to claim 25, wherein, The at least one processor is configured to: The null space report is used to optimize the multi-UE beam management process for multiple UEs including the UE, such that the downlink signal directed to one of the multiple UEs is in the null space of the other UEs.

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