CN116868533A - Group delay mitigation for accuracy enhancement in RTT techniques - Google Patents

Abstract

In an aspect of the disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus may be a UE. The UE measures the RX-TX time difference at baseband for the UE at baseband. The UE compensates for the RX-TX time difference of the UE at the baseband to estimate the RX-TX time difference of the UE at the antenna. The UE transmits to the network an RX-TX time difference for the UE at the antenna with an indication that the reference point is at the antenna and an indication of the TX chain or the timing delay error level of the TX chain expected to be used by the UE during the measurement or compensation.

Description

Group delay mitigation for accuracy enhancement in RTT techniques

Cross Reference to Related Applications

The application claims the benefit of the following applications: U.S. provisional application titled "PROCEDURE TO ASSIST NETWORK FOR TRANSMISSION TIMING CALIBRATION FOR POSITIONING ACCURACY ENHANCEMENT", serial No. 63/145,050, filed on 3/2/2021; U.S. provisional application Ser. No. 63/154,023, entitled "FURTHER ENHANCEMENT FOR MULTIPLE-RTT FOR POSITIONING ACCURACY ENHANCEMENT", filed on 26, 2, 2021; U.S. provisional application titled "FURTHER ACCURACY ENHANCEMENT FOR MULTIPLE-RTT TECHNIQUE", serial No. 63/169,265 filed on 1, month 4 of 2021; and U.S. provisional application filed at month 8 of 2021 under the name "ACCURACY ENHANCEMENT FOR M-RTT TECHNIQUE", serial No. 63/236,262; all of these applications are expressly incorporated herein by reference in their entirety.

Technical Field

The present disclosure relates generally to communication systems, and more particularly to techniques for locating User Equipment (UE).

Background

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcast. A typical wireless communication system may employ multiple-access techniques capable of supporting communication with multiple users by sharing the available system resources. Examples of such multiple access techniques include code division multiple access (code division multiple access, CDMA) systems, time division multiple access (time division multiple access, TDMA) systems, frequency division multiple access (frequency division multiple access, FDMA) systems, orthogonal frequency division multiple access (orthogonal frequency division multiple access, OFDMA) systems, single-carrier frequency division multiple access (single-carrier frequency division multiple access, SC-FDMA) systems, and time division synchronous code division multiple access (time division synchronous code division multiple access, TD-SCDMA) systems.

These multiple access techniques have been employed in various telecommunications standards to provide a common protocol that enables different wireless devices to communicate at the urban, national, regional, and even global levels. An example telecommunications standard is the 5G New Radio (NR). The 5G NR is part of a continuous mobile broadband evolution promulgated by the third generation partnership project (Third Generation Partnership Project,3 GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., with the internet of things (Internet of Things, ioT)) and other requirements. Some aspects of 5G NR may be based on the 4G long term evolution (Long Term Evolution, LTE) standard. Further improvements in the 5G NR technology are needed. These improvements are also applicable to other multiple access techniques and telecommunication standards employing these techniques.

Disclosure of Invention

The following presents a simplified summary of one or more aspects in order to provide a basic understanding of such aspects. This summary is not an extensive overview of all contemplated aspects, and is intended to neither identify key or critical elements of all aspects nor delineate the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that is presented later.

In an aspect of the disclosure, a method, computer-readable medium, and apparatus are provided. In an aspect of the disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus may be a UE. The UE measures the RX-TX time difference at baseband for the UE at baseband. The UE compensates for the RX-TX time difference of the UE at the baseband to estimate the RX-TX time difference of the UE at the antenna. The UE transmits to the network an RX-TX time difference for the UE at the antenna with an indication that the reference point is at the antenna and an indication of the TX chain or the timing delay error level of the TX chain expected to be used by the UE during measurement or compensation.

In another aspect of the disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus may be a base station. The base station measures the RX-TX time difference at baseband for the base station at baseband. The base station compensates for the base station's RX-TX time difference at the baseband to estimate the base station's RX-TX time difference at the antenna for the base station's transmission and reception points (transmission and reception point, TRP). The base station transmits to the location management function an RX-TX time difference at the antenna for the base station with an indication that the reference point is at the antenna and an indication of the timing delay error level of the TX chain or TX chains used by the TRP during measurement or compensation.

In yet another aspect of the disclosure, a method, computer-readable medium, and apparatus are provided. The apparatus may be a location management function. The location management function receives, from a base station of the UE, an RX-TX time difference of the UE at the antenna with an indication that a reference point associated with the RX-TX time difference of the UE at the antenna is at the antenna of the UE. The location management function receives from a base station an RX-TX time difference at an antenna for the base station with an indication that a reference point associated with the RX-TX time difference at the antenna for the base station is at the antenna of a Transmit and Receive Point (TRP) of the base station. The location management function receives a first association indication that the RX-TX time difference at the antenna of the base station is associated with the TX chain or a timing delay error level of the TX chain. The location management function receives a second association indication that the RX-TX time difference at the antenna for the UE is associated with the TX chain or a timing delay error level for the TX chain. The location management function determines a time of flight of signals transmitted between the TRP and the UE based on the RX-TX time difference of the UE at the antenna and the RX-TX time difference of the base station at the antenna.

To the accomplishment of the foregoing and related ends, one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed and the description is intended to include all such aspects and their equivalents.

Drawings

Fig. 1 is a schematic diagram illustrating an example of a wireless communication system and an access network.

Fig. 2 is a schematic diagram illustrating a base station communicating with a UE in an access network.

Fig. 3 illustrates an example logical architecture of a distributed access network.

Fig. 4 illustrates an example physical architecture of a distributed access network.

Fig. 5 is a diagram illustrating an example of a DL-centric subframe.

Fig. 6 is a diagram illustrating an example of UL-centric subframes.

Fig. 7 is a diagram illustrating communication between Transmission and Reception Points (TRP) and User Equipment (UE).

Fig. 8 is another diagram illustrating communication between TRP and UE.

Fig. 9 is a flow chart of a method (process) for determining a UE RX-TX time difference.

Fig. 10 is a flow chart of a method (process) for determining a base station RX-TX time difference.

Fig. 11 is a flow chart of a method (process) for determining time of flight.

Fig. 12 is a schematic diagram illustrating an example of a hardware implementation of an apparatus employing a processing system.

Fig. 13 is a schematic diagram illustrating an example of a hardware implementation of another apparatus employing a processing system.

Fig. 14 is a schematic diagram illustrating an example of a hardware implementation of yet another apparatus employing a processing system.

Detailed Description

The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of the various concepts. It will be apparent, however, to one skilled in the art that the concepts may be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form in order to avoid obscuring such concepts.

Aspects of a telecommunications system 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 figures by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

As an example, an element or any portion of an element or any combination of elements may be implemented as a "processing system" comprising one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (graphics processing unit, GPU), central processing units (central processing unit, CPU), application processors, digital signal processors (digital signal processor, DSP), reduced instruction set computing (reduced instruction set computing, RISC) processors, system-on-chip (systems on a chip, soC), baseband processors, field programmable gate arrays (field programmable gate array, FPGA), programmable logic devices (programmable logic device, PLD), state machines, gating logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout this disclosure. One or more processors in the processing system may execute the software. Software should be construed broadly to mean instructions, instruction sets, code segments, program code, programs, subroutines, software components, applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, and the like, whether referred to as software, firmware, middleware, microcode, hardware description language, or other language.

Thus, in one or more example aspects, the functions described may be implemented in hardware, software, or any combination thereof. If implemented in software, the functions may be stored on or encoded as one or more instructions or code on a computer-readable medium. Computer readable media includes computer storage media. A storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise random-access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (electrically erasable programmable ROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of the above-described types of computer-readable media, or any other media that can be used to store computer-executable code in the form of instructions or data structures that can be accessed by a computer.

Fig. 1 is a schematic diagram illustrating an example of a wireless communication system and an access network 100. A wireless communication system, also referred to as a wireless wide area network (wireless wide area network, WWAN), includes a base station 102, a UE 104, an evolved packet core (Evolved Packet Core, EPC) 160, and another core network 190 (e.g., a 5G core (5 gcore,5 gc)). Base station 102 may include a macrocell (high power cellular base station) and/or a small cell (low power cellular base station). The macrocell includes a base station. Small cells include femto cells, pico cells, and micro cells.

A base station 102 configured for 4G LTE, collectively referred to as an evolved universal mobile telecommunications system (Universal Mobile Telecommunications System, UMTS) terrestrial radio access network (Evolved Universal Mobile Telecommunications System Terrestrial Radio Access Network, E-UTRAN), may interface with EPC 160 over a backhaul link 132 (e.g., SI interface). A base station 102 configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN)) may interface with a core network 190 through a backhaul link 184. Among other functions, the base station 102 may perform one or more of the following functions: user data transfer, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, non-access stratum (NAS) message allocation, NAS node selection, synchronization, radio access network (radio access network, RAN) sharing, multimedia broadcast multicast services (multimedia broadcast multicast service, MBMS), subscriber and device tracking, RAN information management (RAN information management, RIM), paging, positioning, and delivery of alert messages. Base stations 102 may communicate with each other directly or indirectly (e.g., through EPC 160 or core network 190) over backhaul link 134 (e.g., an X2 interface). The backhaul link 134 may be wired or wireless.

The base station 102 may communicate wirelessly with the UE 104. Each base station 102 may provide communication coverage for a respective geographic coverage area 110. There may be overlapping geographic coverage areas 110. For example, the small cell 102 'may have a coverage area 110' that overlaps with the coverage area 110 of one or more macro base stations 102. A network comprising both small cells and macro cells may be referred to as a heterogeneous network. The heterogeneous network may also include a home Evolved Node B (eNB) (Home Evolved Node B, heNB) that may provide services to a restricted group called a closed subscriber group (closed subscriber group, CSG). The communication link 120 between the base station 102 and the UE 104 may include Uplink (UL) (also known as reverse link) transmissions from the UE 104 to the base station 102 and/or Downlink (DL) (also known as forward link) transmissions from the base station 102 to the UE 104. Communication link 120 may use multiple-input multiple-output (MIMO) antenna techniques including spatial multiplexing, beamforming, and/or transmit diversity. The communication link may be through one or more carriers. The base station 102/UE 104 may use a spectrum up to Y MHz (e.g., 5, 10, 15, 20, 100, 400, etc.) bandwidth per component carrier in each direction that is allocated in carrier aggregation up to a total of Y x MHz (x component carriers) for transmission. The carriers may or may not be adjacent to each other. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., DL may be allocated more or less carriers than UL). The component carriers may include a primary component carrier and one or more secondary component carriers. The primary component carrier may be referred to as a primary cell (PCell), and the secondary component carrier may be referred to as a secondary cell (SCell).

Some UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use the DL/UL WWAN spectrum. The D2D communication link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (physical sidelink broadcast channel, PSBCH), a physical sidelink discovery channel (physical sidelink discovery channel, PSDCH), a physical sidelink shared channel (physical sidelink shared channel, PSSCH), and a physical sidelink control channel (physical sidelink control channel, PSCCH). D2D communication may be through various wireless D2D communication systems such as, for example, flashLinQ, wiMedia, bluetooth, zigBee, wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

The wireless communication system may also include a Wi-Fi Access Point (AP) 150 that communicates with a Wi-Fi Station (STA) 152 via a communication link 154 in the 5GHz unlicensed spectrum. When communicating in the unlicensed spectrum, STA 152/AP 150 may perform a clear channel assessment (clear channel assessment, CCA) prior to communication to determine whether a channel is available.

The small cell 102' may operate in licensed and/or unlicensed spectrum. When operating in unlicensed spectrum, the small cell 102' may employ NR and use the same 5GHz unlicensed spectrum as used by Wi-Fi AP 150. The use of NR small cells 102' in the unlicensed spectrum may improve coverage of the access network and/or increase capacity of the access network.

Base station 102, whether a small cell 102' or a large cell (e.g., macro base station), may comprise an eNB, a gndeb (gNB), or another type of base station. Some base stations, such as the gNB 180, may operate in the legacy sub-6 GHz spectrum, millimeter wave (mmW) frequencies, and/or near mmW frequencies in communication with the UE 104. When the gNB 180 operates in mmW or near mmW frequencies, the gNB 180 may be referred to as a mmW base station. The extremely high frequency (extremely high frequency, EHF) is part of the RF in the electromagnetic spectrum. EHF has a wavelength in the range of 30GHz to 300GHz and between 1 mm and 10 mm. The radio waves in the frequency band may be referred to as millimeter waves. The near mmW may extend down to a frequency of 3GHz and a wavelength of 100 millimeters. The ultra-high frequency (super high frequency, SHF) band extends between 3GHz and 30GHz, also known as centimetre waves. Communications using mmW/near mmW radio bands (e.g., 3GHz-300 GHz) have extremely high path loss and short distances. The mmW base station 180 may utilize beamforming 182 with the UE 104 to compensate for extremely high path loss and short distances.

The base station 180 may transmit the beamformed signals to the UE 104 in one or more transmit directions 108 a. The UE 104 may receive the beamformed signals from the base station 180 in one or more receive directions 108 b. The UE 104 may also transmit the beamformed signals in one or more transmit directions to the base station 180. The base station 180 may receive the beamformed signals from the UEs 104 in one or more directions. The base stations 180/UEs 104 may perform beam training to determine the best receive direction and transmit direction for each base station 180/UE 104. The transmission direction and the reception direction of the base station 180 may be the same or different. The transmission direction and the reception direction of the UE 104 may be the same or different.

EPC 160 may include a mobility management entity (Mobility Management Entity, MME) 162, other MMEs 164, a serving gateway 166, a multimedia broadcast multicast service (Multimedia Broadcast Multicast Service, MBMS) gateway 168, a broadcast multicast service center (Broadcast Multicast Service Center, BM-SC) 170, and a packet data network (Packet Data Network, PDN) gateway 172.MME 162 may communicate with home subscriber server (Home Subscriber Server, HSS) 174. The MME 162 is a control node that handles signaling between the UE 104 and the EPC 160. In general, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transmitted through the serving gateway 166, which serving gateway 166 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 BM-SC 170 are connected to an IP service 176.IP services 176 may include the internet, intranets, IP multimedia subsystem (IP Multimedia Subsystem, IMS), PS streaming services, and/or other IP services. The BM-SC 170 may provide functionality for MBMS user service provisioning and delivery. The BM-SC 170 may be used as an entry point for content provider MBMS transmissions, may be used to authorize and initiate MBMS bearer services within a public land mobile network (public land mobile network, PLMN), and may be used to schedule MBMS transmissions. The MBMS gateway 168 may be used to allocate MBMS traffic to base stations 102 belonging to a multicast broadcast single frequency network (Multicast Broadcast Single Frequency Network, MBSFN) area broadcasting a particular service and may be responsible for session management (start/stop) and for collecting eMBMS related charging information.

The core network 190 may include access and mobility management functions (Access and Mobility Management Function, AMF) 192, other AMFs 193, location management functions (location management function, LMF) 198, session management functions (Session Management Function, SMF) 194, and user plane functions (User Plane Function, UPF) 195. The AMF 192 may communicate with a unified data management (Unified Data Management, UDM) 196. The AMF 192 is a control node that handles signaling between the UE 104 and the core network 190. In general, SMF 194 provides QoS flows and session management. All user internet protocol (Internet protocol, IP) packets are transmitted through the UPF 195. The UPF 195 provides UE IP address assignment as well as other functions. The UPF 195 is connected to an IP service 197. The IP services 197 may include the internet, intranets, IP multimedia subsystems (IP Multimedia Subsystem, IMS), PS streaming services, and/or other IP services.

A base station may also be called a gNB, a Node B, an evolved Node B (eNB), an access point, a base transceiver station, a radio base station, a radio transceiver, a transceiver function, a basic service set (basic service set, BSS), an extended service set (extended service set, ESS), a transmission and reception point (transmit reception point, TRP), or some other suitable terminology. The base station 102 provides an access point for the UE 104 to the EPC 160 or the core network 190. Examples of UEs 104 include a cellular telephone, a smart phone, a session initiation protocol (session initiation protocol, SIP) phone, a laptop, a personal digital assistant (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 computer, a smart device, a wearable device, a vehicle, an electricity meter, an air pump, a large or small kitchen appliance, a healthcare device, an implant, a sensor/actuator, a display, or any other similar functional device. Some UEs 104 may be referred to as IoT devices (e.g., parking timers, air pumps, toasters, vehicles, heart monitors, etc.). The UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, or some other suitable terminology.

Although the present disclosure may refer to 5G New Radio (NR), the present disclosure may be applicable to other similar areas such as LTE, LTE-Advanced (LTE-a), code Division Multiple Access (CDMA), global system for mobile communications (GSM), or other wireless/radio access technologies.

Fig. 2 is a block diagram of a base station 210 in communication with a UE 250 in an access network. In DL, IP packets from the core network 160 may be provided to the controller/processor 275. Controller/processor 275 implements layer 3 and layer 2 functions. Layer 3 includes a radio resource control (radio resource control, RRC) layer, and layer 2 includes a packet data convergence protocol (packet data convergence protocol, PDCP) layer, a Radio Link Control (RLC) layer, and a medium access control (medium access control, MAC) layer. Controller/processor 275 provides: RRC layer functions associated with broadcast of system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-radio access technology (radio access technology, RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functions associated with header compression/decompression, security (ciphering, deciphering, integrity protection, integrity verification) and handover support functions; RLC layer functions associated with transmission of upper layer Packet Data Units (PDUs), error correction by ARQ, concatenation, segmentation and reassembly of RLC service data units (service data unit, SDU), re-segmentation of RLC data PDUs and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing of MAC SDUs onto Transport Blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction by HARQ, priority handling and logical channel prioritization.

A Transmit (TX) processor 216 and a Receive (RX) processor 270 implement layer 1 functions associated with various signal processing functions. Layer 1, which includes the Physical (PHY) layer, may include error detection on the transport channel, forward error correction (forward error correction, FEC) encoding/decoding of the transport channel, interleaving, rate matching, mapping on the physical channel, modulation/demodulation of the physical channel, and MIMO antenna processing. TX processor 216 processes the 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-quadrature amplitude modulation, M-QAM)). The coded and modulated symbols may then be split into parallel streams. Each stream may then be mapped to OFDM subcarriers, multiplexed with reference signals (e.g., pilots) in the time and/or frequency domain, and then combined together using an inverse fast fourier transform (Inverse Fast Fourier Transform, IFFT) to produce a physical channel carrying the time domain OFDM symbol stream. The OFDM streams are spatially precoded to produce a plurality of spatial streams. The channel estimates from the channel estimator 274 may be used to determine coding and modulation schemes and for spatial processing. The channel estimate may be derived from a reference signal and/or channel condition feedback transmitted by the UE 250. Each spatial stream may then be provided to a different antenna 220 via a separate transmitter 218 TX. Each transmitter 218TX may modulate an RF carrier with a respective spatial stream for transmission.

At the UE 250, each receiver 254RX receives a signal through its respective antenna 252. Each receiver 254RX recovers information modulated onto an RF carrier and provides the information to a Receive (RX) processor 256.TX processor 268 and RX processor 256 implement layer 1 functions associated with various signal processing functions. RX processor 256 may perform spatial processing on the information to recover any spatial streams destined for UE 250. If multiple spatial streams are destined for UE 250, they may be combined into a single OFDM symbol stream by RX processor 256. The RX processor 256 then converts the OFDM symbol stream from the time domain to the frequency domain using a fast fourier transform (Fast Fourier Transform, FFT). The frequency domain signal comprises a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols and reference signals on each subcarrier are recovered and demodulated by determining the most likely signal constellation points transmitted by base station 210. These soft decisions may be based on channel estimates computed by channel estimator 258. The soft decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the base station 210 on the physical channel. The data and control signals are then provided to a controller/processor 259 that implements layer 3 and layer 2 functions.

The controller/processor 259 can be associated with a memory 260 that stores program codes and data. Memory 260 may be referred to as a computer-readable medium. In the UL, the controller/processor 259 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, and control signal processing to recover IP packets from the core network 160. The controller/processor 259 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

Similar to the functionality described in connection with DL transmissions by the base station 210, the controller/processor 259 provides RRC layer functions associated with system information (e.g., MIB, SIB) acquisition, RRC connection, and measurement reporting; PDCP layer functions associated with header compression/decompression and security (ciphering, deciphering, integrity protection, integrity verification); RLC layer functions associated with upper layer PDU delivery, error correction by ARQ, concatenation, segmentation and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions 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 by HARQ, priority handling and logical channel prioritization.

TX processor 268 may use channel estimation results from the reference signals or feedback transmitted by base station 210 by channel estimator 258 to select the appropriate coding and modulation scheme and facilitate spatial processing. The spatial streams generated by TX processor 268 may be provided to different antennas 252 via separate transmitters 254 TX. Each transmitter 254TX may modulate an RF carrier with a respective spatial stream for transmission. UL transmissions are processed at base station 210 in a manner similar to that described in connection with the receiver functionality at UE 250. Each receiver 218RX receives a signal through its corresponding antenna 220. Each receiver 218RX recovers information modulated onto an RF carrier and provides the information to the RX processor 270.

The controller/processor 275 may be associated with a memory 276 that stores program codes and data. Memory 276 may be referred to as a computer-readable medium. In the UL, the controller/processor 275 provides demultiplexing between transport and logical channels, packet reassembly, deciphering, header decompression, control signal processing to recover IP packets from the UE 250. IP packets from the controller/processor 275 may be provided to the core network 160. The controller/processor 275 is also responsible for error detection using ACK and/or NACK protocols to support HARQ operations.

A New Radio (NR) may refer to a radio configured to operate according to a new air interface (e.g., other than an orthogonal frequency division multiple access (Orthogonal Frequency Divisional Multiple Access, OFDMA) based air interface) or a fixed transport layer (e.g., other than Internet Protocol (IP)). NR may utilize OFDM with Cyclic Prefix (CP) on uplink and downlink and may include support for half-duplex operation using time division duplex (time division duplexing, TDD). NR may include critical tasks targeting enhanced mobile broadband (Enhanced Mobile Broadband, eMBB) services with a wide bandwidth (e.g., over 80 MHz), millimeter waves (mmW) targeting high carrier frequencies (e.g., 60 GHz), massive MTC (emtc) targeting non-backward compatible MTC technologies, and/or ultra-reliable low latency communication (ultra-reliable low latency communication, URLLC) services.

A single component carrier bandwidth of 100MHz may be supported. In one example, an NR Resource Block (RB) may span 12 subcarriers having a subcarrier bandwidth of 60kHz within a 0.125ms duration or a bandwidth of 15kHz within a 0.5ms duration. Each radio frame may consist of 20 or 80 subframes (or NR slots) of length 10 ms. Each subframe may indicate a link direction (i.e., DL or UL) for data transmission, and the link direction of each subframe may be dynamically switched. Each subframe may include DL/UL data and DL/UL control data. UL and DL subframes for NR may be described in more detail below with respect to fig. 5 and 6.

The NR RAN may include a Central Unit (CU) and a Distributed Unit (DU). An NR BS (e.g., a gNB, a 5G node B, a transmission and reception point (transmission reception point, TRP), an Access Point (AP)) may correspond to one or more BSs. An NR cell may be configured as an access cell (ACell) or a data only cell (DCell). For example, the RAN (e.g., a central unit or a distributed unit) may configure the cells. The DCell may be a cell for carrier aggregation or dual connectivity, and may not be used for initial access, cell selection/reselection, or handover. In some cases, the DCell may not transmit a synchronization signal (synchronization signal, SS), and in some cases, the DCell may transmit the SS. The NR BS may transmit a downlink signal indicating a cell type to the UE. Based on the cell type indication, the UE may communicate with the NR BS. For example, the UE may determine an NR BS considering cell selection, access, handover, and/or measurement based on the indicated cell type.

Fig. 3 illustrates an example logical architecture of a distributed RAN 300 in accordance with aspects of the present disclosure. The 5G access node 306 may include an access node controller (access node controller, ANC) 302. The ANC may be a Central Unit (CU) of the distributed RAN. The backhaul interface to the next generation core network (next generation core network, NG-CN) 304 may terminate at the ANC. The backhaul interface to the neighboring next generation access node (next generation access node, NG-AN) 310 may terminate at the ANC. ANC may include one or more TRP 308 (which may also be referred to as BS, NR BS, nodeb, 5G NB, AP, or some other terminology). As described above, TRP may be used interchangeably with "cell".

TRP 308 may be a Distributed Unit (DU). TRP may be connected to one ANC (ANC 302) or more than one ANC (not shown). For example, for RAN sharing, radio as a service (radio as a service, raaS), and service specific ANC deployments, TRP may be connected to more than one ANC. The TRP may include one or more antenna ports. The TRP may be configured to provide services to the UE either individually (e.g., dynamic selection) or jointly (e.g., joint transmission).

The local architecture of the distributed RAN 300 may be used to illustrate the forwarding definition. An architecture may be defined that supports a forward-drive solution across different deployment types. For example, the architecture may be based on transmit network capabilities (e.g., bandwidth, latency, and/or jitter). The architecture may share functionality and/or components with LTE. According to aspects, a next generation AN (NG-AN) 310 may support dual connectivity with NR. The NG-AN may share common preambles for LTE and NR.

The architecture may enable collaboration between and among TRPs 308. For example, there may be collaboration within the TRP and/or across TRP via ANC 302. According to aspects, there may be no need/presence of an interface between TRPs.

According to aspects, dynamic configuration of split logic functions may exist within the architecture of the distributed RAN 300. The PDCP, RLC, MAC protocol may be adaptively placed at ANC or TRP.

Fig. 4 illustrates an example physical architecture of a distributed RAN 400 in accordance with aspects of the present disclosure. The centralized core network element (centralized core network unit, C-CU) 402 may host core network functions. The C-CU may be centrally deployed. The C-CU functions may be offloaded (e.g., to an advanced wireless service (advanced wireless service, AWS)) in an effort to handle peak capacity. The centralized RAN unit (centralized RAN unit, C-RU) 404 may host one or more ANC functions. Alternatively, the C-RU may host the core network functions locally. The C-RU may have a distributed deployment. The C-RU may be closer to the network edge. Distributed Units (DUs) 406 may host one or more TRPs. The DUs may be located at the edge of a Radio Frequency (RF) enabled network.

Fig. 5 is a diagram 500 illustrating an example of a DL-centric subframe. The DL-centric sub-frame may comprise a control portion 502. The control portion 502 may exist in a beginning or beginning portion of a DL-centric sub-frame. The control portion 502 may include various scheduling information and/or control information corresponding to various portions of the DL-centric sub-frame. In some configurations, the control portion 502 may be a Physical DL Control Channel (PDCCH), as shown in fig. 5. DL-centric sub-frames may also include DL data portion 504.DL data portion 504 may sometimes be referred to as the payload of a DL-centric sub-frame. The DL data portion 504 may include communication resources for transmitting DL data from a scheduling entity (e.g., UE or BS) to a subordinate entity (e.g., UE). In some configurations, DL data portion 504 may be a Physical DL Shared Channel (PDSCH).

DL-centric sub-frames may also include a common UL portion 506. The common UL portion 506 may sometimes be referred to as a UL burst, a common UL burst, and/or various other suitable terms. The common UL portion 506 may include feedback information corresponding to various other portions of the DL-centric sub-frame. For example, the common UL portion 506 may include feedback information corresponding to the control portion 502. Non-limiting examples of feedback information may include an ACK signal, a NACK signal, a HARQ indicator, and/or various other suitable types of information. The common UL portion 506 may include additional or alternative information, such as information related to random access channel (random access channel, RACH) procedures, scheduling requests (scheduling request, SR), and various other suitable types of information.

As shown in fig. 5, the end of DL data portion 504 may be separated in time from the beginning of common UL portion 506. This time separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. The separation provides time from DL communication (e.g., a receiving operation of a subordinate entity (e.g., UE)) to UL communication (e.g., a transmission of a subordinate entity (e.g., UE)) for handover. Those of ordinary skill in the art will appreciate that the foregoing is merely one example of DL-centric subframes and that alternative structures may exist that have similar features without necessarily departing from aspects described herein.

Fig. 6 is a diagram 600 illustrating an example of UL-centric sub-frames. The UL-centric sub-frame may comprise a control portion 602. The control portion 602 may be present in a beginning or beginning portion of a UL-centric subframe. The control portion 602 in fig. 6 may be similar to the control portion 502 described above with reference to fig. 5. UL-centric sub-frames may also include UL data portion 604.UL data portion 604 may sometimes be referred to as the payload of a UL-centric subframe. The UL portion may refer to communication resources for transmitting UL data from a subordinate entity (e.g., UE) to a scheduling entity (e.g., UE or BS). In some configurations, the control portion 602 may be a Physical DL Control Channel (PDCCH).

As shown in fig. 6, the end of the control portion 602 may be separated in time from the beginning of the UL data portion 604. This time separation may sometimes be referred to as a gap, guard period, guard interval, and/or various other suitable terms. This separation provides time for switching from DL communication (e.g., a receive operation by the scheduling entity) to UL communication (e.g., a transmission by the scheduling entity). UL-centric sub-frames may also include a common UL portion 606. The common UL portion 606 in fig. 6 may be similar to the common UL portion 506 described above with reference to fig. 5. Additionally or alternatively, the common UL portion 606 may include information related to channel quality indicators (channel quality indicator, CQI), sounding reference signals (sounding reference signal, SRS), and various other suitable types of information. Those of ordinary skill in the art will appreciate that the foregoing is merely one example of UL-centric subframes and that alternative structures may exist that have similar features without necessarily departing from aspects described herein.

In some cases, two or more subordinate entities (e.g., UEs) may communicate with each other using side-downlink signals. Real world applications for such side-link communications may include public safety, proximity services, UE-to-network relay, vehicle-to-vehicle (V2V) communications, internet of things (Internet of Everything, ioE) communications, ioT communications, mission critical grids, and/or various other suitable applications. In general, a side-downlink signal may refer to a signal transmitted from one subordinate entity (e.g., UE 1) to another subordinate entity (e.g., UE 2) without relaying the communication through a scheduling entity (e.g., UE or BS), even though the scheduling entity may be used for scheduling and/or control purposes. In some examples, the side-uplink signal may be transmitted using a licensed spectrum (as opposed to a wireless local area network that typically uses an unlicensed spectrum).

Fig. 7 is a diagram 700 illustrating communication between a Transmission and Reception Point (TRP) and a User Equipment (UE). In this example, the UE 704 may be in communication with one or more of TRP-1 712, TRP-2 716, and TRP-3 718. Furthermore, each of TRP-1 712, TRP-2 716, and TRP-3 718 may be operated by one of base station 702, base station 706, and base station 708. The UE 704 has an antenna panel I782 and an antenna panel II 784.TRP-1 712 has antenna panel a 791 and antenna panel B792. TRP-2 716 has antenna panel C795 and antenna panel D796.

Fig. 8 is another diagram 800 illustrating communication between TRP and UE. The baseband of TRX-1 712 operates according to TRP 1-TX-baseband slot boundary timing 810, which includes DL slots N through (n+3). The baseband signals (including the positioning reference signals) generated at baseband pass through the TX RF chain of the antenna panel a 791 of the TRX-1 712 to generate corresponding Radio Frequency (RF) signals. The TX RF chain may include a digital-to-analog converter (analog audio converter, DAC), a filter, an external Power Amplifier (PA), and a duplexer/switch. Antenna panel A791 transmits RF signals in DL slots N through (N+3) according to TRP1-TX-RF slot boundary timing 820. The TRR1-TX-RF slot boundary timing 820 is delayed by Δt compared to the TRP 1-TX-baseband slot boundary timing 810 _{TX_TRP1_panel_A} 。

After the time of flight (tof 1 in this example), the UE 704 is at T ₁₀ The signal transmitted from TRP-1 712 (including PRS) in DL slot N starts to be received at antenna panel I782. An RX RF chain (e.g., including a duplexer/switch, an external low-noise amplifier (LNA), a filter, and an analog-to-digital converter (ADC)) that signals pass through antenna panel I782, and at Δt _{RX_UE_panel_I} Is of (1) T after a delay ₁₂ Reaching the baseband of the UE 704.

The base band of the UE 704 determines DL slots N through (n+3) according to the UE-RX-base band slot boundary timing 830. In this example, the starting boundary of DL slot N is time reference point 0. DL slot N according to the UE-RX-baseband slot boundary timing 830 has a delay of μ after DL slot N according to TRP 1-TX-baseband slot boundary timing 810.

More specifically, UE 704 starts receiving DL slot N at antenna panel I782 at:

T ₁₀ ＝Δt _{TX_TRP1_panel_A} +tof1-μ。

the baseband of the UE 704 starts receiving DL slot N at the following times:

T ₁₂ ＝T ₁₀ +Δt _{RX_UE_panel_I} ＝Δt _{TX_TRP1_panel_A} +tof1-μ+Δt _{RX_UE_panel_I} 。

subsequently, in response to receiving the signal in DL slot N (including PRS) from TRP-1 712, UE 704 may transmit a signal (including sounding reference signal (souding reference signal, SRS)) to TRP-1 712 in UL slot (n+1) according to UE-TX-baseband slot boundary timing 834. More specifically, the baseband of UE 704 begins generating baseband signals for UL slot (n+1) at the following times:

T ₂₀ =one slot period-TA,

where one slot period is the duration of the slot and TA is the timing advance. The baseband signals (including SRS) generated at baseband are passed through the TX RF chain of the antenna panel I782 of the UE 704 to generate RF signals. The TX RF chain may include a DAC, a filter, an external PA, a diplexer/switch. Antenna panel I782 is set at T according to UE-TX-RF slot boundary timing 838 ₂₂ Transmitting RF signals, T ₂₂ Is Δt after the UE-TX-baseband slot boundary timing 834 _{TX_UE_panel_I} . Thus, the first and second substrates are bonded together,

T ₂₂ =one slot cycle-ta+Δt _{TX_UE_panel_I} 。

The RX baseband of TRP-1 712 operates according to TRP 1-RX-baseband slot boundary timing 840, which is aligned with TRP 1-TX-baseband slot boundary timing 810. At TRP-1 712, the start of UL slot (N+1)The boundary is the time reference point 0. In this example, after tof1, TRP-1 712 is at T ₃₀ The signal in UL slot (n+1) is received at antenna panel a 791. Thus, the first and second substrates are bonded together,

T ₃₀ ＝μ-TA+Δt _{TX_UE_panel_I} +tof1。

the signal passes through the RX RF chain of antenna panel a 791 (e.g., including a diplexer/switch, external LNA, filter and ADC), and at Δt _{RX_TRP1_panel_A} T after a delay of (a) ₃₂ Reaching the baseband of TRP-1 712. Thus, the first and second substrates are bonded together,

T ₃₂ ＝T ₃₀ +Δt _{RX_TRP1_panel_A}

＝μ-TA+Δt _{TX_UE_panel_I} +tof1+Δt _{RX_TRP1_panel_A} 。

in response to receiving the signal in UL slot (n+1), TRP-1 712 may begin transmitting the signal in DL slot (n+2). More specifically, TRP-1 712 is at T ₄₀ Transmission starts at the baseband. T (T) ₄₀ Is the starting boundary of DL slot (n+2). Thus, the first and second substrates are bonded together,

T ₄₀ =one slot cycle.

Similar to that described above, at Δt _{TX_TRP1_panel_A} Thereafter T ₄₂ Antenna panel a 791 of TRP-1 712 begins to transmit in DL slot (n+2). Thus, the first and second substrates are bonded together,

T ₄₂ =one slot period+Δt _{TX_TRP1_panel_A} 。

UE 704 may measure at baseband [ UE RX-TX difference _baseband ]。[UE RX-TX difference _baseband ]A time difference between a point in time at which the UE 704 starts receiving signals at baseband and a point in time at which the UE 704 starts transmitting signals in response (e.g., an uplink time slot closest in time to the received downlink time slot). In this example, at baseband,

[UE RX-TX difference _baseband ]＝T ₁₂ -T ₂₀

＝Δt _{TX_TRP1_panel_A} +tof1-μ+Δt _{RX_UE_panel_I} one slot period + TA.

In addition, the UE 704 may also calculateUE RX-TX difference related to TX and RX antennas of UE 704 _antenna ]。[UE RX-TX difference _antenna ]A time difference between a point in time at which the UE 704 starts receiving signals at the RX antenna and a point in time at which the UE 704 starts transmitting signals at the TX antenna in response. In this example of the present invention, in this case,

[UE RX-TX difference _antenna ]＝T ₁₀ -T ₂₂

＝Δt _{TX_TRP1_panel_A} +tof1- μ -one slot cycle +TA- Δt _{TX_UE_panel_I} 。

Thus, [ UE RX-TX difference ] _baseband ]And [ UE RX-TX difference ] _antenna ]The differences are as follows:

[UE RX-TX difference _antenna ]-[UE RX-TX difference _baseband ]＝Δt _{TX_UE_panel_I} +Δt _{RX_UE_panel_I} 。

in some configurations, the UE 704 may estimate/measure Δt _{TX_UE_panel_I} +Δt _{RX_UE_panel_I} Which is the sum of the delays of the TX group delay and the RX group delay at antenna panel I782. The UE 704 may then determine the UE RX-TX difference measured at baseband _baseband ]Compensation is performed to obtain [ UE RX-TX difference ] _antenna ]And then report the resulting UE RX-TX difference to its serving base station (e.g., base station 702) _antenna ]The serving base station forwards the information to the LMF 754 via the AMF 750. Similarly, UE 704 may estimate/measure a delay sum of the TX group delay and the RX group delay at antenna panel II 784 and generate a corresponding UE RX-TX difference that may be reported to the serving base station _antenna ]。

Similarly, TRP-1 712 may measure [ gNB RX-TX difference at baseband ] _baseband ]。[gNB RX-TX difference _baseband ]A time difference between a point in time at which TRP-1 712 starts receiving signals at baseband and a point in time at which TRP-1 712 starts transmitting signals in response (e.g., a downlink time slot closest in time to the received uplink time slot). In this example, at baseband,

[gNB RX-TX difference _baseband ]＝T ₃₂ -T ₄₀

＝μ-TA+Δt _{TX_UE_panel_I} +tof1+Δt _{RX_TRP1_panel_A} -one slot cycle.

In addition, TRP-1 712 may also calculate [ gNB RX-TX difference about the TX and RX antennas of TRP-1 712 _antenna ]。[gNB RX-TX difference _antenna ]A time difference between a point in time at which TRP-1 712 begins to receive signals at the RX antenna and a point in time at which TRP-1 712 begins to transmit signals at the TX antenna in response. In this example of the present invention, in this case,

[gNB RX-TX difference _antenna ]＝T ₃₀ -T ₄₂

＝μ-TA+Δt _{TX_UE_panel_I} +tof1-one slot cycle- Δt _{TX_TRP1_panel_A} 。

Thus, [ gNB RX-TX difference ] _baseband ]And [ gNB RX-TX difference _antenna ]The differences are as follows:

[gNB RX-TX difference _antenna ]-[gNB RX-TX difference _baseband ]

＝Δt _{TX_TRP1_panel_A} +Δt _{RX_TRP1_panel_A} 。

in some configurations, a serving base station (e.g., base station 702) of TRP-1 712 may estimate/measure Δt _{TX_TRP1_panel_A} +Δt _{RX_TRP1_panel_A} Which is the sum of the delays of the TX group delay and the RX group delay at antenna panel a 791. TRP-1 712 may then utilize the delay and the delay to [ gNB RX-TX difference measured at baseband ] _baseband ]Compensation is performed to obtain [ gNB RX-TX difference _antenna ]. Similarly, TRP-1 712 may estimate/measure the delay sum of the TX and RX group delays at antenna panel B792 and generate a corresponding [ gNB RX-TX difference ] _antenna ]. In addition, in the case of the optical fiber,

[UE RX-TX difference _antenna ]+[gNB RX-TX difference _antenna ]＝2*tof1。

thus, the value of tof1 can be derived.

When the UE 704 calculates [ UE RX-TX difference ] as described above _antenna ]At this time, the UE 704 needs to be at T ₂₀ A first TA value (TA 1) is determined or estimated for calculation. TA1 is the result of the estimation because in some cases the UE 704 is actually at T ₂₀ No signal is sent. Thus, the UE 704 calculates:

[UE RX-TX difference _antenna ]’＝Δt _{TX_TRP1_panel_A} +tof1- μ -one slot cycle +TA1- Δt _{TX_UE_panel_I} 。

In this calculation, the UE 704 is at T ₂₀ The SRS is not transmitted. TA1 is a predefined (expected) timing advance for the upcoming potential uplink transmission.

When TRP-1 712 calculates [ gNB RX-TX difference _antenna ]At this time, TRP-1 712 receives that the UE 704 is at T ₂₀ The signal transmitted using the second TA value (TA 2). Thus, TRP-1 712 calculation:

[gNB RX-TX difference _antenna ]’＝μ-TA2+Δt _{TX_UE_panel_I} +tof1-one slot cycle- Δt _{TX_TRP1_panel_A} 。

For this calculation, the UE 704 is at T ₂₀ SRS is transmitted and TA2 is the actual timing advance for SRS transmission. In some cases, TA1 and TA2 may have the same value. In some cases, TA1 and TA2 may have different values.

In some configurations, when UE 704 reports [ UE RX-TX difference to its serving base station _baseband ]Or [ UE RX-TX difference ] _antenna ]The UE also reports information for calculating [ UE RX-TX difference ] _baseband ]Or [ UE RX-TX difference ] _antenna ]A value TA1 of a predefined timing advance of (c). The time stamp for the measurement is also reported. The TA value is calculated as follows:

TA＝(N _TA +N _TA,offset )*T _c 。

The UE 704 may report the TA1 value to its serving base station in an information element (information element, IE) or report N separately in an IE _TA And N _TA,offset A component.

In some scenarios, the UE 704 uses TA2 at T as described above ₂₀ Transmitting SRS to TRP-1 712 for measurement of [ gNB RX-TX difference _baseband ]Or [ gNB RX-TX difference _antenna ]. The UE 704 may determine whether the values of TA1 and TA2 are the same. When the values are not the same, the UE 704 may also report a TA adjustment to its serving base station, which is TA2-TA1. The serving base station also forwards this information to the LMF 754. The UE 704 may also report a timestamp for SRS transmission (e.g., at T ₂₀ ). When TA1 is equal to TA2, then the UE 704 may not need to report the TA adjustment amount.

As described above, UE 704 may be based on the delay sum (Δt) of antenna panel I782 _{TX_UE_panel_I} +Δt _{RX_UE_panel_I} ) To calculate [ UE RX-TX difference ] _antenna ]. TRP-1 712 may be based on the delayed sum (Δt) of antenna panel A791 _{TX_TRP1_panel_A} +Δt _{RX_TRP1_panel_A} ) To calculate [ gNB RX-TX difference _antenna ]。

In some configurations, the UE 704 and TRP-1 712 (through their serving base stations) may report to the LMF 754 the statistics (variance, uncertainty level) of the delay sums of the associated antenna panels used. In addition, [ UE RX-TX difference ] _antenna ]And [ gNB RX-TX difference _antenna ]Can be used to cancel each other's TX group delays, i.e. (Δt) residing in DL and UL measurements, respectively _{TX_TRP1_panel_A} -Δt _{TX_UE_panel_I} ) And (Deltat) _{TX_UE_panel_I} -Δt _{TX_TRP1_panel_A} ). The UE 704 may then also report the identity of the TX antenna panel (RF chain) for SRS transmission in order to make the appropriate pairing for cancellation. TRP-1 712 may also report TX antenna panels (RF chains) for PRS transmissions.

Thus, it is assumed that there is a correlation (not practical) between SRS transmission and the panel RF used. UE 704 at UE RX-TX difference _baseband ]Or [ UE RX-TX difference ] _antenna ]This association is provided to the LMF 754 in the measurement report because different panels/RF chains may have different group delays.

When the UE or TRP compensates for a measurement associated with an antenna panel and performed at baseband with the sum of the delays of the TX group delay and the RX group delay of the antenna panel, the compensation result may be used or considered equivalent to the measurement performed at the antenna. Further, as described above, the delayed sum of the TX group delay and the RX group delay cancel the RX group delay term within the measurement at baseband. Thus, there is no RX group delay term within the measurement at the antenna.

When the UE has measurements using different pairs of RX antenna panels and TX antenna panels, after rx+tx group delay compensation, this is equivalent to all measurements being made by using the same RX antenna panel but different TX antenna panels. The UE may send an indication of the RX-TX time difference at the antenna via its serving base station to the location management function. The indication may be an RX index indicating an RX antenna panel or a delay error level of the RX antenna panel (or a timing error group (timing error group, TEG)). The indication may be a TX index indicating a TX antenna panel or a delay error level (or a Timing Error Group (TEG)) of the TX antenna panel. The range of the RX index is 1. Antenna panels with similar group delays (e.g., within a configured time frame) are on the same delay error level or in the same TEG. The range of TX index may be greater than 1 as UE capability for a certain frequency band. For example, measurement a reports the associated RX index=0 and TX index=0; measurement B reports the associated RX index=0 and TX index=1; and measurement C reports the associated RX index=0 and TX index=2.

Fig. 9 is a flow chart 900 of a method (process) for determining a UE RX-TX time difference. The method may be performed by a UE (e.g., UE 704). At operation 902, the UE measures an RX-TX time difference of the UE at the baseband. At operation 904, the UE compensates for the RX-TX time difference of the UE at the baseband to estimate the RX-TX time difference of the UE at the antenna. At operation 906, the UE transmits to a network (e.g., LMF 754) an RX-TX time difference for the UE at the antenna with an indication that the reference point is at the antenna and an indication of a timing delay error level of a Transmit (TX) chain or TX chains expected to be used by the UE during measurement or compensation.

In some configurations, the RX-TX time difference at the baseband for the UE indicates a time difference between (a) a point in time at which the UE starts receiving the first downlink slot containing the DL-PRS at the baseband and (b) a point in time at which the UE expects to start transmitting the first uplink slot (an uplink slot closest in time to the first downlink slot containing the DL-PRS) at the baseband. In some configurations, the RX-TX time difference of the UE at the baseband is compensated for using a first delay sum associated with a pair of TX and RX chains expected to be used by the UE to transmit the first uplink time slot to estimate the RX-TX time difference of the UE at the antenna, wherein the RX-TX time difference of the UE at the antenna indicates a time difference between (a) a point in time at which reception of the first downlink time slot containing DL-PRS at the receive antenna of the UE is started and (b) a point in time at which transmission of the first uplink time slot is to be started at the transmit antenna of the UE. In some configurations, the TX chain is intended to be used by the UE to transmit the first uplink time slot during measurement or backoff.

In some configurations, the first delay sum is a sum of a TX group delay and an RX group delay at a pair of TX and RX chains intended for use by the UE to transmit the first uplink time slot. In some configurations, the RX-TX time difference at the antenna for the UE is a function of TX group delay at the Transmit and Receive Points (TRPs) of the base station, time of flight between the UE and the TRPs, timing difference between the UE slot and the corresponding TRP slot, TX group delay at the UE, first TA that the UE will use for the intended transmission of the first uplink slot.

At operation 908, the UE measures a delay sum of TX group delays and RX group delays for each pair of TX and RX chains of the UE. At operation 910, the UE transmits to the network a TA adjustment associated with a TA used by the UE to transmit a second uplink slot containing the SRS. At operation 912, the UE transmits to the network an indication of a timing delay error level of the TX chain or the TX chain used by the UE to transmit the second uplink slot containing the SRS.

Fig. 10 is a flow chart 1000 of a method (process) for determining a base station RX-TX time difference. The method may be performed by a base station (e.g., base station 702). At operation 1002, the base station measures an RX-TX time difference at baseband for the base station at baseband. At operation 1004, the base station compensates for an RX-TX time difference at the base band for the base station to estimate an RX-TX time difference at the antenna for the base station at a Transmit and Receive Point (TRP) of the base station. At operation 1006, the base station transmits to the location management function an RX-TX time difference at the antenna for the base station with an indication that the reference point is at the antenna and an indication of a timing delay error level of a Transmit (TX) chain or TX chains used by the TRP during measurement or compensation.

In some configurations, the RX-TX time difference at the base band of the base station indicates a time difference between (a) a point in time at which the base station starts receiving a second uplink slot containing SRS from a User Equipment (UE) at the base band and (b) a point in time at which the base station expects to transmit a second downlink slot (a downlink slot closest in time to the second uplink slot containing SRS) at the base band. In some configurations, the second delay sum is utilized to compensate for the RX-TX time difference of the base station at baseband to estimate the RX-TX time difference of the base station at the antenna. The RX-TX time difference at the antenna by the base station indicates a time difference between (a) a point in time at which reception of a second uplink slot containing the SRS at the receiving antenna of the TRP is to begin and (b) a point in time at which transmission of a second downlink slot at the transmitting antenna of the TRP is to begin, the second delay being associated with a pair of TX and RX chains intended for use by the TRP to transmit the second downlink slot. In some configurations, the TX chain is used by the TRP to transmit the second downlink time slot during measurement or backoff.

In some configurations, the second delay sum is a sum of TX group delay and RX group delay at a pair of TX chain and RX chain expected to be used by the TRP to transmit the second downlink time slot. In some configurations, the RX-TX time difference at the antenna of the base station is a function of the timing difference between the UE slot and the corresponding TRP slot, the second TA used by the UE to transmit the second uplink slot containing the SRS, the TX group delay at the UE, the time of flight between the TRP and the UE, and the TX group delay at the TRP.

At operation 1008, the base station receives a TA adjustment associated with a TA used by the UE to transmit a second uplink slot containing the SRS. The base station then sends the TA adjustment to the location management function. At operation 1010, the base station transmits an indication of a timing delay error level of a TX chain or a TX chain used by the TRP to transmit a first downlink slot containing DL-PRS to a location management function. At operation 1012, the base station sends an indication to the location management function of a timing delay error level of the TX chain or TX chain expected to be used by the TRP to send the second downlink time slot. At operation 1014, the base station measures a delay sum of a TX group delay and an RX group delay for each pair of TX and RX chains of the TRP.

Fig. 11 is a flow chart 1100 of a method (process) for determining time of flight. The method may be performed by a location management function (e.g., LMF 754). At operation 1102, a location management function receives, from a base station of a UE, an RX-TX time difference of the UE at an antenna with an indication that a reference point associated with the RX-TX time difference of the UE at the antenna is at the antenna of the UE. At operation 1104, the location management function receives, from a base station, an RX-TX time difference at an antenna for the base station with an indication that a reference point associated with the RX-TX time difference at the antenna for the base station is at an antenna of a Transmit and Receive Point (TRP) of the base station. At operation 1106, the location management function receives an indication of an RX-TX time difference at the antenna for the UE by utilizing the TX and RX group delays at the UE and compensating for the RX-TX time difference at the baseband for the UE. The RX-TX time difference at the antenna for the UE indicates a time difference between (a) a point in time at which reception of a first downlink slot containing DL-PRS at a receive antenna of the UE is started and (b) a point in time at which transmission of a first uplink slot at a transmit antenna of the UE is to be started, wherein the first uplink slot is an uplink slot closest in time to the first downlink slot containing DL-PRS and intended to be transmitted.

At operation 1108, the location management function receives an indication of an estimate of the RX-TX time difference at the antenna for the base station by utilizing the TX group delay at the TRP and the second delay of the RX group delay and compensating for the RX-TX time difference at the base station at the base band. The RX-TX time difference at the antenna by the base station indicates a time difference between (a) a point in time at which reception of the second uplink slot containing the SRS at the receiving antenna of the TRP of the base station is to begin and (b) a point in time at which transmission of the second downlink slot at the transmitting antenna of the TRP is to begin. The second downlink slot is the downlink slot closest in time to the second uplink slot containing the SRS and intended to be transmitted.

At operation 1110, the location management function receives a first association indication that an RX-TX time difference at an antenna of a base station is associated with a TX chain or a timing delay error level of the TX chain. At operation 1112, the location management function receives a second association indication that the RX-TX time difference at the antenna for the UE is associated with the TX chain or a timing delay error level for the TX chain. At operation 1114, the location management function determines a time of flight of signals transmitted between the TRP and the UE based on the RX-TX time difference of the UE at the antenna and the RX-TX time difference of the base station at the antenna.

In some configurations, the location management function may receive a TA adjustment associated with a TA used by the UE to transmit SRS in a second uplink slot containing SRS. The time of flight is also determined based on the TA adjustment. In some configurations, the location management function selects an RX-TX time difference at the antenna for the UE and an RX-TX time difference at the antenna for the base station based on (a) an association of the TX chain of TRPs with the TX chain of the UE or (b) an association of the timing delay error level of the TX chain of TRPs with the timing delay error level of the TX chain of the UE. The location management function performs a combined calculation of the RX-TX time difference at the antenna for the UE and the RX-TX time difference at the antenna for the base station to determine the time of flight between the TRP and the UE.

Fig. 12 is a schematic diagram 1200 illustrating an example of a hardware implementation of an apparatus 1702 employing a processing system 1214. The apparatus 1702 may be a base station. The processing system 1214 may be implemented using a bus architecture, represented generally by the bus 1224. The bus 1224 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1214 and the overall design constraints. The bus 1224 links together various circuits including one or more processors and/or hardware components, represented by the one or more processor 1204, the receive component 1764, the transmit component 1770, the measurement component 1776, and the compensation component 1778, as well as the computer-readable medium/memory 1206. Bus 1224 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits.

The processing system 1214 may be coupled to the transceivers 1210, and the transceivers 1210 may be one or more of the transceivers 254. The transceiver 1210 is coupled to one or more antennas 1220, which antennas 1220 may be the communication antenna 220.

The transceiver 1210 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1210 receives signals from the one or more antennas 1220, extracts information from the received signals, and provides the extracted information to the processing system 1214 (particularly the receiving component 1764). In addition, the transceiver 1210 receives information from the processing system 1214 (particularly the transmission component 1770) and generates signals to be applied to one or more antennas 1220 based on the received information.

The processing system 1214 includes one or more processors 1204 coupled to a computer-readable medium/memory 1206. The one or more processors 1204 are responsible for general processing, including the execution of software stored on the computer-readable medium/memory 1206. The software, when executed by the one or more processors 1204, causes the processing system 1214 to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory 1206 may also be used for storing data that is manipulated by the one or more processors 1204 when executing software. The processing system 1214 also includes at least one of a receiving component 1764, a transmitting component 1770, a compensating component 1778, and a measuring component 1776. The components may be software components resident/stored in the computer readable medium/memory 1206 that run in the one or more processors 1204, one or more hardware components coupled to the one or more processors 1204, or some combination thereof. The processing system 1214 may be a component of the base station 210 and may include the memory 276 and/or at least one of the TX processor 216, the RX processor 270, and the controller/processor 275.

In one configuration, means 1702 for wireless communication includes means for performing each of the operations of fig. 10. The foregoing means may be one or more of the foregoing components of the apparatus 1702 and/or the processing system 1214 of the apparatus 1702 configured to perform the functions recited by the foregoing means.

As described above, the processing system 1214 may include the TX processor 216, the RX processor 270, and the controller/processor 275. Accordingly, in one configuration, the foregoing means may be the TX processor 216, the RX processor 270, and the controller/processor 275 configured to perform the functions recited by the foregoing means.

Fig. 13 is a schematic diagram 1300 illustrating an example of a hardware implementation of a device 1302 employing a processing system 1314. The apparatus 1302 may be a UE. The processing system 1314 may be implemented using a bus architecture, represented generally by the bus 1324. The bus 1324 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1314 and the overall design constraints. The bus 1324 links together various circuits including one or more processors and/or hardware components, represented by the one or more processors 1304, the receiving component 1364, the sending component 1370, the compensating component 1378, the measuring component 1376, and the computer-readable medium/memory 1306. The bus 1324 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits.

The processing system 1314 may be coupled to the transceiver 1310, and the transceiver 1310 may be one or more of the transceivers 254. The transceiver 1310 is coupled to one or more antennas 1320, which antennas 1320 may be the communication antenna 252.

The transceiver 1310 provides a means for communicating with various other apparatus over a transmission medium. The transceiver 1310 receives a signal from the one or more antennas 1320, extracts information from the received signal, and provides the extracted information to the processing system 1314 (particularly the receiving component 1364). In addition, transceiver 1310 receives information from processing system 1314 (and in particular, transmission component 1370) and generates signals based on the received information to be applied to one or more antennas 1320.

The processing system 1314 includes one or more processors 1304 coupled to a computer-readable medium/memory 1306. The one or more processors 1304 are responsible for general processing, including the execution of software stored on the computer-readable medium/memory 1306. The software, when executed by the one or more processors 1304, causes the processing system 1314 to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory 1306 may also be used for storing data that is manipulated by the one or more processors 1304 when executing software. The processing system 1314 further includes at least one of a receiving component 1364, a sending component 1370, a compensating component 1378, and a measuring component 1376. The components may be software components resident/stored in the computer readable medium/memory 1306 running in the one or more processors 1304, one or more hardware components coupled to the one or more processors 1304, or some combination thereof. The processing system 1314 may be a component of the UE 250 and may include the memory 260 and/or at least one of the TX processor 268, the RX processor 256, and the communication processor 259.

In one configuration, the means 1302 for wireless communication comprises means for performing each of the operations of fig. 9. The foregoing means may be one or more of the foregoing components of the apparatus 1302 and/or the processing system 1314 of the apparatus 1302 configured to perform the functions recited by the foregoing means.

As described above, processing system 1314 may include TX processor 268, RX processor 256, and communication processor 259. Accordingly, in one configuration, the foregoing means may be the TX processor 268, the RX processor 256, and the communication processor 259 configured to perform the functions recited by the foregoing means.

Fig. 14 is a schematic diagram 1400 illustrating an example of a hardware implementation of an apparatus 1402 employing a processing system 1414 and one or more other hardware components. The apparatus 1402 may implement location management functionality. The processing system 1414 may be implemented using a bus architecture, represented generally by the bus 1424. The bus 1424 may include any number of interconnecting buses and bridges depending on the specific application of the processing system 1414 and the overall design constraints. The bus 1424 links together various circuits including one or more processors and/or hardware components (represented by the processor 1404, the computer-readable medium/memory 1406, the network controller 1410, etc.).

The bus 1424 may also link various other circuits such as timing sources, peripherals, voltage regulators, and power management circuits, which are well known in the art, and therefore, will not be described any further.

The processing system 1414 may be coupled to the network controller 1410. The network controller 1410 provides a means for communicating with various other devices over a network. The network controller 1410 receives signals from the network, extracts information from the received signals, and provides the extracted information to the processing system 1414 (particularly the communication device 1478). In addition, the network controller 1410 receives information from the processing system 1414 (particularly the communication part 1478), and generates a signal to be transmitted to the network based on the received information. The processing system 1414 includes a processor 1404 coupled to a computer-readable medium/memory 1406. The processor 1404 is responsible for general processing, including the execution of software stored on the computer-readable medium/memory 1406. The software, when executed by the processor 1404, causes the processing system 1414 to perform the various functions described supra for any particular apparatus. The computer-readable medium/memory 1406 may also be used for storing data that is manipulated by the processor 1404 when executing software. The processing system further includes at least one of a data receiving section 1464, a data calculating section 1470, and an RF chain associating section 1476. The components may be software components resident/stored in the computer readable medium/memory 1406 that run in the processor 1404, one or more hardware components coupled to the processor 1404, or some combination thereof.

The apparatus 1402 has means for performing the operations described above with reference to fig. 11. The foregoing means may be one or more of the foregoing components of the means 1402 and/or the processing system 1414 of the means 1402 configured to perform the functions recited by the foregoing means.

It should be understood that the specific order or hierarchy of blocks in the processes/flowcharts disclosed is an illustration of exemplary approaches. Based on design preferences, it is understood that the specific order or hierarchy of blocks in the processes/flowcharts may be rearranged. Further, some blocks may be combined or omitted. The accompanying method claims present elements of the various blocks in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are 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". The word "exemplary" means "serving as an example, instance, or illustration" in this document. Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects. The term "some" means one or more unless specifically stated otherwise. Combinations such as "at least one of A, B or C", "one or more of A, B or C", "at least one of A, B and C", "one or more of A, B and C", and "A, B, C or any combination thereof" include any combination of A, B and/or C, and may include multiples of a, multiples of B, or multiples of C. Specifically, a combination such as "at least one of A, B or C", "one or more of A, B or C", "at least one of A, B and C", "one or more of A, B and C" and "A, B, C or any combination thereof" may be a alone, B alone, C, A and B, A and C, B and C, or a and B and C, wherein any such combination may comprise one or more members or members of A, B or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Furthermore, 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, "etc. cannot be used in place of the word" means. Thus, unless the phrase "means for..once again..is used to explicitly state a claim element, that element must not be interpreted as a means-plus-function.

Claims (18)

1. A method of wireless communication of a User Equipment (UE), the method comprising:

measuring an RX-TX time difference at baseband for the UE;

compensating for the RX-TX time difference of the UE at the baseband to estimate the RX-TX time difference of the UE at the antenna; and

an RX-TX time difference at the antenna for the UE is transmitted to a network, the RX-TX time difference at the antenna for the UE having an indication that a reference point is at the antenna and an indication of a Transmit (TX) chain or a timing delay error level of the TX chain expected to be used by the UE during the measurement or the compensation.

2. The method of claim 1, wherein an RX-TX time difference at a baseband for the UE indicates a time difference between (a) a point in time at which the UE starts receiving a first downlink slot containing DL-PRS at the baseband and (b) a point in time at which the UE expects to start transmitting a first uplink slot at the baseband, the first uplink slot being an uplink slot closest in time to the first downlink slot containing DL-PRS;

wherein the RX-TX time difference of the UE at the baseband is compensated for using a first delay and associated with a pair of TX and RX chains expected to be used by the UE to transmit the first uplink time slot to estimate the RX-TX time difference of the UE at the antenna, wherein the RX-TX time difference of the UE at the antenna indicates a time difference between (a) a point in time at which the reception of the first downlink time slot containing DL-PRS at the receive antenna of the UE is started and (b) a point in time at which the transmission of the first uplink time slot at the transmit antenna of the UE is to be started; and is also provided with

Wherein the TX chain is intended for use by a UE to transmit the first uplink time slot during the measurement or the backoff.

3. The method of claim 2, wherein the first sum of delays is a sum of TX group delays and RX group delays at the pair of the TX and RX chains that are intended to be used by the UE to transmit the first uplink time slot.

4. The method of claim 2, wherein the RX-TX time difference at an antenna for the UE is a function of a TX group delay at a Transmit and Receive Point (TRP) of a base station, a time of flight between the UE and the TRP, a timing difference between a UE slot and a corresponding TRP slot, a TX group delay at the UE, a first TA to be used by the UE for an intended transmission of the first uplink slot.

5. The method of claim 1, the method further comprising:

the sum of the delays of the TX group delay and the RX group delay of each pair of TX and RX chains of the UE is measured.

6. The method of claim 1, the method further comprising:

a Timing Advance (TA) adjustment associated with a TA of a second uplink slot used by the UE to transmit the SRS is transmitted to the network.

7. The method of claim 1, the method further comprising:

an indication of a timing delay error level of a TX chain or the TX chain used by the UE to transmit a second uplink slot including SRS is sent to the network.

8. A method of wireless communication of a base station, the method comprising:

measuring an RX-TX time difference at baseband of the base station;

compensating for an RX-TX time difference of the base station at a base band to estimate an RX-TX time difference of the base station at an antenna of a Transmission and Reception Point (TRP) of the base station;

the method also includes transmitting an RX-TX time difference at the antenna for the base station to a location management function, the RX-TX time difference at the antenna for the base station having an indication that a reference point is at the antenna and an indication of a timing delay error level of a Transmit (TX) chain or the TX chain used by the TRP during the measurement or the compensation.

9. The method of claim 8, wherein the RX-TX time difference at the base station indicates a time difference between (a) a point in time at which the base station begins to receive a second uplink slot containing SRS from a User Equipment (UE) at the base band and (b) a point in time at which the base station expects to transmit a second downlink slot at the base band, the second downlink slot being a downlink slot closest in time to the second uplink slot containing SRS;

Wherein the base station's RX-TX time difference at the baseband is compensated for using a second delay sum associated with a pair of TX and RX chains expected to be used by the TRP to transmit the second downlink time slot to estimate the base station's RX-TX time difference at the antenna, wherein the base station's RX-TX time difference at the antenna indicates a time difference between (a) a point in time at which the second uplink time slot containing the SRS is beginning to be received at the TRP's receive antenna and (b) a point in time at which the second downlink time slot is about to begin to be transmitted at the TRP's transmit antenna; and is also provided with

Wherein the TX chain is used by the TRP to transmit the second downlink time slot during the measurement or the backoff.

10. The method of claim 9, wherein the second delay sum is a sum of TX group delays and RX group delays at the pair of the TX and RX chains expected to be used by the TRP to transmit the second downlink time slot.

11. The method of claim 9, wherein the RX-TX time difference at the antenna of the base station is a function of a timing difference between a UE slot and a corresponding TRP slot, a second TA used by the UE to transmit the second uplink slot containing SRS, a TX group delay at the UE, a time of flight between the TRP and the UE, and a TX group delay at the TRP.

12. The method of claim 9, the method further comprising:

receiving a Timing Advance (TA) adjustment associated with a TA used by the UE to transmit the second uplink slot containing SRS; and

and sending the TA adjustment amount to the position management function.

13. The method of claim 9, the method further comprising:

transmitting an indication of a timing delay error level of a TX chain or the TX chain used by the TRP to transmit the first downlink slot containing DL-PRS to the location management function; and

an indication of a timing delay error level of a TX chain or the TX chain expected to be used by the TRP to transmit the second downlink time slot is sent to the location management function.

14. The method of claim 8, the method further comprising:

the sum of the delays of the TX group delay and the RX group delay of each pair of TX and RX chains of the TRP is measured.

15. A method of operating a location management function, the method comprising:

receiving, from a base station of a UE, an RX-TX time difference of the UE at an antenna, the RX-TX time difference of the UE at the antenna having an indication that a reference point associated with the RX-TX time difference of the UE at the antenna of the UE;

Receiving from the base station an RX-TX time difference of the base station at the antenna, the RX-TX time difference of the base station at the antenna having an indication that a reference point associated with the RX-TX time difference of the base station at the antenna is at a Transmit and Receive Point (TRP) of the base station;

receiving a first association indication that the RX-TX time difference of the base station at the antenna is associated with a TX chain or a timing delay error level of the TX chain;

receiving a second association indication that the RX-TX time difference of the UE at the antenna is associated with a TX chain or a timing delay error level of the TX chain; and

a time of flight of a signal transmitted between the TRP and the UE is determined based on an RX-TX time difference of the UE at an antenna and an RX-TX time difference of the base station at an antenna.

16. The method of claim 15, the method further comprising:

receiving an indication of an RX-TX time difference at an antenna for the UE by utilizing a TX group delay and a first delay of the RX group delay at the UE and compensating for the RX-TX time difference at a baseband for the UE, wherein the RX-TX time difference at the antenna for the UE indicates a time difference between (a) a point in time at which reception of a first downlink time slot containing DL-PRS at a receive antenna of the UE is started and (b) a point in time at which transmission of a first uplink time slot at a transmit antenna of the UE is to be started, wherein the first uplink time slot is an uplink time slot closest in time to the first downlink time slot containing DL-PRS and intended to be transmitted; or (b)

An indication of an RX-TX time difference at an antenna for a base station is estimated by utilizing a TX group delay and a second delay of the RX group delay at the TRP and compensating for the RX-TX time difference at the base station, wherein the RX-TX time difference at the antenna for the base station indicates a time difference between (a) a point in time at which reception of a second uplink slot containing SRS at a receiving antenna of the TRP of the base station is started and (b) a point in time at which transmission of a second downlink slot at a transmitting antenna of the TRP is to be started, wherein the second downlink slot is a downlink slot closest in time to the second uplink slot containing SRS and intended to be transmitted.

17. The method of claim 16, the method further comprising:

a Timing Advance (TA) adjustment associated with a TA used by the UE to transmit SRS in the second uplink slot containing SRS is received, wherein the time of flight is determined based also on the TA adjustment.

18. The method of claim 15, the method further comprising:

selecting an RX-TX time difference at an antenna for the UE and an RX-TX time difference at the antenna for the base station based on (a) an association of the TX chain of the TRP with the TX chain of the UE or (b) an association of a timing delay error level of the TX chain of the TRP with a timing delay error level of the TX chain of the UE; and

A combined calculation of the RX-TX time difference at the antenna for the UE and the RX-TX time difference at the antenna for the base station is performed to determine a time of flight between the TRP and the UE.