Methods, apparatus and computer-readable media for supporting high-speed vehicle-to-vehicle communication

Abstract

During device-to-device communication between two devices, if the first UE is traveling at high speed, the second UE may not be able to reliably receive communications transmitted from the first UE to the second UE. Therefore, the travel speed of the sending UE can be considered when determining the transmission configuration. According to one aspect, the UE can determine its travel speed. The UE can determine the transmission configuration for device-to-device communication based on its travel speed. The UE can then transmit device-to-device communication based on this transmission configuration.

Description

[0001] This application is a divisional application of the invention patent application filed on March 2, 2017, with application number 201780018523.0 and entitled "Method, Apparatus and Computer-readable Medium for Supporting High Speed ​​in Vehicle-to-Vehicle Communication".

[0002] Cross-reference to related applications

[0003] This application claims priority from the following U.S. applications:

[0004] U.S. Provisional Application No. 62 / 311,057, filed on March 21, 2016, entitled "SUPPORTING HIGH SPEEDS IN LTE-D BASED V2V",

[0005] U.S. Provisional Application No. 62 / 311,754, filed on May 4, 2016, entitled “SUPPORTING HIGH SPEEDS IN VEHICLE-TO-VEHICLE COMMUNICATION”, and

[0006] U.S. Patent Application No. 15 / 365,384, filed on November 30, 2016, entitled "Supporting High Species in Vehicular-to-Vehicular Communication,"

[0007] Therefore, the entire contents of these applications are expressly incorporated into this document by reference. Technical Field

[0008] In general, this disclosure relates to communication systems, and more specifically, to vehicle-to-vehicle communication between devices. Background Technology

[0009] Wireless communication systems have been widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems can use multiple access technologies that support 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.

[0010] These multiple access technologies have been adopted in various telecommunications standards to provide a universal protocol enabling different wireless devices to communicate across city limits, countries, regions, and even globally. An exemplary telecommunications standard is Long Term Evolution (LTE). LTE is an evolution set of the Universal Mobile Telecommunications System (UMTS) mobile standard released by the 3rd Generation Partnership Project (3GPP). LTE is designed to use OFDMA on the downlink, SC-FDMA on the uplink, and multiple-input multiple-output (MIMO) antenna technology to support mobile broadband access by improving spectral efficiency, reducing costs, and enhancing service. However, with the continued increase in demand for mobile broadband access, there is a need to further improve LTE technology. Furthermore, these improvements can also be applied to other multiple access technologies and communication standards that use these technologies.

[0011] Device-to-device (D2D) communication on licensed spectrum is being developed to provide a way for user equipment to communicate directly with another user equipment in LTE. Continuous improvements are being made to provide reliable device-to-device communication on licensed spectrum in various environments. Summary of the Invention

[0012] To provide a basic understanding of one or more aspects of the invention, a brief overview of these aspects is given below. This overview is not an exhaustive summary of all anticipated aspects, nor is it intended to identify key or essential elements of all aspects, or to describe the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simple form as a prelude to the detailed description that follows.

[0013] During D2D communication between two devices, if the first UE is traveling at high speed, the second UE may not be able to reliably receive communications sent from the first UE to the second UE. Therefore, the travel speed of the sending UE can be considered when determining the transmission configuration of the sending UE. Furthermore, when a UE receives control channels and data from other UEs, decoding the control channels can be complex. Therefore, methods to reduce the complexity of decoding the control channels are desired.

[0014] In one aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication are provided. The apparatus may be a UE (User Equipment). The apparatus can determine the UE's travel speed. Based on the UE's travel speed, the apparatus can determine a transmission configuration for device-to-device communication of the UE. The device-to-device communication may occur on licensed spectrum or unlicensed spectrum. The apparatus can transmit the device-to-device communication based on the transmission configuration.

[0015] In another aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication are provided. The apparatus may be a UE (User Equipment). The apparatus may receive communication from a sending UE via device-to-device communication. This device-to-device communication may occur on licensed or unlicensed spectrum. The apparatus may determine a corresponding SA resource set from among multiple scheduling allocation (SA) resource sets for receiving the communication from the sending UE. Available SA resources may be allocated into the multiple SA resource sets based on the type of SA transmission configuration. The apparatus may decode SAs based on the communication in the corresponding SA resource set. The apparatus may determine a data transmission configuration based on the SAs in the corresponding SA resource set. The apparatus may receive data from the sending UE based on this data transmission configuration.

[0016] In another aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication are provided. The apparatus may be a UE (User Equipment). The apparatus can determine an enabled group hopping for a plurality of demodulation reference signal (DM-RS) sequences associated with a control channel for device-to-device communication. The plurality of DM-RS sequences may be carried on a plurality of DM-RS symbols in the control channel of a subframe. The apparatus can determine the plurality of DM-RS sequences by applying a group hopping pattern to the plurality of DM-RS symbols. The apparatus can use the plurality of DM-RS sequences to transmit or receive scheduling allocations for the device-to-device communication.

[0017] To provide a basic understanding of one or more aspects of the invention, a brief overview of these aspects is given below. This overview is not an exhaustive summary of all anticipated aspects, nor is it intended to identify key or essential elements of all aspects, or to describe the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simple form as a prelude to the detailed description that follows. Attached Figure Description

[0018] Figure 1 This is a diagram illustrating an example of a wireless communication system and access network.

[0019] Figure 2A , 2B Figures 2C and 2D are LTE examples illustrating the DL frame structure, the DL channel in the DL frame structure, the UL frame structure, and the UL channel in the UL frame structure, respectively.

[0020] Figure 3 This is a diagram illustrating an example of an evolved Node B (eNB) and a User Equipment (UE) in an access network.

[0021] Figure 4This is a diagram illustrating an example of a device-to-device communication system.

[0022] Figure 5 This is a diagram illustrating an example of a V2V communication system.

[0023] Figure 6 This is an example graph showing the error rates experienced by the UE under various conditions.

[0024] Figure 7 This is an example diagram of an SA resource, shown as one aspect of this disclosure.

[0025] Figure 8 This is a flowchart illustrating a method of wireless communication, according to one aspect of the present disclosure.

[0026] Figure 9 This is a flowchart illustrating a method of wireless communication, according to one aspect of the present disclosure.

[0027] Figure 10 This is a diagram illustrating an example of enabling group hopping for DM-RS symbols in a subframe.

[0028] Figure 11 This is a flowchart illustrating a method of wireless communication, according to one aspect of the present disclosure.

[0029] Figure 12 This is a conceptual data flow diagram illustrating the data flow between different units / components in an exemplary device.

[0030] Figure 13 This is a diagram illustrating an example of a hardware implementation for a device using a processing system. Detailed Implementation

[0031] The specific embodiments described below with reference to the accompanying drawings are intended merely to describe various configurations and not to indicate that the concepts described herein can be implemented only in these configurations. Specific details are included in the specific embodiments to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be implemented without using these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring these concepts.

[0032] Various apparatuses and methods are now described with reference to some aspects of a telecommunications system. These apparatuses and methods will be described in the following detailed embodiments and depicted 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 these elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0033] For example, an element, any part of an element, or any combination of elements can be implemented as a "processing system" including 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, system-on-a-chip (SoCs), baseband processors, field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gate logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described throughout this disclosure. One or more processors in a processing system can execute software. Software should be broadly interpreted as meaning instructions, instruction sets, code, code segments, program code, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., regardless of whether it is referred to as software, firmware, middleware, microcode, hardware description languages, or other terms.

[0034] Therefore, in one or more exemplary embodiments, the functions described herein can be implemented in hardware, software, or any combination thereof. When implemented in software, these functions can be stored or encoded as one or more instructions or code on a computer-readable medium. A computer-readable medium includes a computer storage medium. The storage medium can be any available medium accessible to a computer. By way of example, and not limitation, such a computer-readable medium can include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of computer-readable media of the foregoing types, or any other medium capable of storing computer-executable code in the form of instructions or data structures and accessible to a computer.

[0035] Figure 1This diagram illustrates an example of a wireless communication system and access network 100. The wireless communication system (also referred to as a Wireless Wide Area Network (WWAN)) includes a base station 102, a UE 104, and an evolved packet core (EPC) 160. The base station 102 may include macro cells (high-power cellular base stations) and / or small cells (low-power cellular base stations). Macro cells include eNBs. Small cells include femtocells, picocells, and microcells.

[0036] Base station 102 (collectively referred to as the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) interacts with EPC 160 via backhaul link 132 (e.g., S1 interface). Among other functions, base station 102 can perform one or more of the following: user data transmission, 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, distribution of Non-Access Stratum (NAS) messages, NAS node selection, synchronization, Radio Access Network (RAN) sharing, Multimedia Broadcast Multicast Service (MBMS), user and device tracking, RAN Information Management (RIM), paging, location, and alarm message delivery. Base stations 102 can communicate directly or indirectly with each other (e.g., via EPC 160) via backhaul link 134 (e.g., X2 interface). Backhaul link 134 can be wired or wireless.

[0037] Base station 102 can wirelessly communicate with UE 104. Each of base stations 102 can provide communication coverage for a corresponding geographic coverage area. Overlapping geographic coverage areas 110 may exist. For example, small cell 102' may have a coverage area 110' that overlaps with the coverage areas 110 of one or more macro base stations 102. A network including small cells and macro cells can be referred to as a heterogeneous network. In addition, a heterogeneous network may also include home node B (eNB) (HeNB), which can provide services to a restricted group called a closed subscriber group (CSG). The communication link 120 between base station 102 and UE 104 may include uplink (UL) (also referred to as reverse link) transmission from UE 104 to base station 102 and / or downlink (DL) (also referred to as forward link) transmission from base station 102 to UE 104. Communication link 120 may use MIMO antenna technology, which includes spatial multiplexing, beamforming, and / or transmit diversity. These communication links may be via one or more carriers. Base station 102 / UE 104 may use up to Y MHz (e.g., 5, 10, 15, 20 MHz) of bandwidth allocated per carrier in a total of up to Y x MHz (x component carriers) of carrier aggregation for transmission in each direction. These carriers may be adjacent to each other or not. The allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL compared to UL). These component carriers may include primary component carriers and one or more secondary component carriers. The primary component carrier may be referred to as the primary cell (PCell), and the secondary component carrier may be referred to as the secondary cell (SCell).

[0038] In addition, the wireless communication system may also include a Wi-Fi access point (AP) 150, which communicates with a Wi-Fi station (STA) 152 via a communication link 154 in the 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, the STA 152 / AP 150 may perform a free channel assessment (CCA) before communication to determine whether the channel is available.

[0039] Small cell 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell 102' can employ LTE and use the same 5 GHz unlicensed spectrum as Wi-Fi AP 150. Small cell 102' employing LTE in unlicensed spectrum can improve access network coverage and / or increase access network capacity. LTE in unlicensed spectrum can be referred to as LTE Unlicensed (LTE-U), Licensed Assisted Access (LAA), or MuLTEfire.

[0040] EPC 160 may include Mobility Management Entity (MME) 162, other MMEs 164, Serving Gateway 166, Multimedia Broadcast Multicast Service (MBMS) Gateway 168, Broadcast Multicast Service Center (BM-SC) 170, and Packet Data Network (PDN) Gateway 172. MME 162 can communicate with Home Subscriber Server (HSS) 174. MME 162 is the control node that handles signaling between UE 104 and EPC 160. Typically, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transmitted through Serving Gateway 166, which is itself connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation and other functions. PDN Gateway 172 and BM-SC 170 are connected to IP Service 176. IP Service 176 may include the Internet, intranet, IP Multimedia Subsystem (IMS), and PS Streaming Service (PSS) and / or other IP services. The BM-SC 170 can provide functions for MBMS user service provisioning and delivery. The BM-SC 170 can serve as an entry point for content provider MBMS transmissions, can be used to authorize and initiate MBMS bearer services in the Public Land Mobile Network (PLMN), and can be used to schedule MBMS transmissions. The MBMS gateway 168 can be used to distribute MBMS services to base stations 102 belonging to the Multicast-Broadcast Single Frequency Network (MBSFN) area belonging to the Broadcast-Specific Service, and can be responsible for session management (start / stop) and collection of billing information related to eMBMS.

[0041] A base station may also be referred to as a Node B, Evolved Node B (eNB), access point, base transceiver, wireless base station, wireless transceiver, transceiver function, Basic Services Set (BSS), Extended Services Set (ESS), or any other suitable term. Base station 102 provides UE 104 with access to EPC 160. Examples of UE 104 include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptop computers, personal digital assistants (PDAs), satellite radio devices, Global Positioning Systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet devices, smart devices, wearable devices, or any other similar functional devices. UE 104 may also be referred to as a station, mobile station, user station, mobile unit, user cell, radio unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile user station, access terminal, mobile terminal, wireless terminal, remote terminal, handheld device, user agent, mobile client, client, or any other suitable term.

[0042] See you again Figure 1In some respects, UE 104 can be configured (198) to: take into account the driving speed of UE 104 when determining the transmission configuration of UE 104, transmit control channels on a set of multiple SA resource sets, and enable group hopping for DM-RS sequences associated with control channels used for device-to-device communication. This device-to-device communication can be vehicle-to-vehicle communication or vehicle-to-everything communication. Referring below to Figures 2 to... Figure 13 Let's further describe the details of the operation performed at point 198.

[0043] Figure 2A This is illustration 200, which shows an example of the DL frame structure in LTE. Figure 2B This is illustration 230, which shows an example of a channel in the DL frame structure of LTE. Figure 2C Figure 250 shows an example of the UL frame structure in LTE. Figure 2D This is illustration 280, showing an example of a channel in the UL frame structure of LTE. Other wireless communication technologies may have different frame structures and / or different channels. In LTE, a frame (10 ms) can be divided into 10 uniformly sized subframes. Each subframe may include two consecutive time slots. These two time slots can be represented using resource lattices, each time slot including one or more concurrent resource blocks (RBs) (also called physical RBs (PRBs)). The resource lattice is then divided into multiple resource elements (REs). In LTE, for a normal cyclic prefix, for a total of 84 REs, an RB contains 12 consecutive subcarriers in the frequency domain and 7 consecutive symbols in the time domain (OFDM symbols for DL; SC-FDMA symbols for UL). For an extended cyclic prefix, for a total of 72 REs, an RB contains 12 consecutive subcarriers in the frequency domain and 6 consecutive symbols in the time domain. The number of bits carried by each RE depends on the scheduling scheme.

[0044] like Figure 2A As shown, some of these REs carry DL reference (pilot) signals (DL-RS) for channel estimation at the UE. DL-RS may include: cell-specific reference signals (CRS) (which are sometimes also called common RS), UE-specific reference signals (UE-RS), and channel state information reference signals (CSI-RS). Figure 2A The diagram shows that CRS corresponds to antenna ports 0, 1, 2, and 3 (indicated as R0, R1, R2, and R3, respectively), UE-RS corresponds to antenna port 5 (indicated as R5), and CSI-RS corresponds to antenna port 15 (indicated as R). Figure 2BExamples of various channels in the DL subframe of a frame are shown. The Physical Control Format Indicator Channel (PCFICH) is located in symbol 0 of slot 0 and carries a Control Format Indicator (CFI) indicating whether the Physical Downlink Control Channel (PDCCH) occupies 1, 2, or 3 symbols. Figure 2B The diagram shows a PDCCH occupying 3 symbols. The PDCCH carries downlink control information (DCI) in one or more control channel elements (CCEs). Each CCE includes nine RE groups (REGs), and each REG includes four consecutive REs in an OFDM symbol. A UE-specific enhanced PDCCH (ePDCCH) that also carries DCI can be used to configure the UE. The ePDCCH can have 2, 4, or 8 RB pairs (…). Figure 2B Two RB pairs are shown, each subset comprising one RB pair. Furthermore, the Physical Hybrid Automatic Repeat Request (ARQ) Indicator Channel (PHICH) is also located in symbol 0 of slot 0 and carries the HARQ indicator (HI) for indicating HARQ acknowledgment (ACK) / negative ACK (NACK) feedback, based on the Physical Uplink Shared Channel (PUSCH). The Primary Synchronization Channel (PSCH) is located in symbol 6 of slot 0 in subframes 0 and 5 of the frame, carrying the Primary Synchronization Signal (PSS) used by the UE to determine subframe timing and physical layer identification. The Secondary Synchronization Channel (SSCH) is located in symbol 5 of slot 0 in subframes 0 and 5 of the frame, carrying the Secondary Synchronization Signal (SSS) used by the UE to determine the Physical Layer Cell Identifier Group Number. Based on the physical layer identifier and the physical layer cell identifier group number, the UE can determine the Physical Cell Identifier (PCI). Based on this PCI, the UE can determine the location of the aforementioned DL-RS. The Physical Broadcast Channel (PBCH) is located within symbols 0, 1, 2, and 3 of slot 1 in subframe 0 of the frame and carries the Master Information Block (MIB). The MIB provides the number of Restricted Frames (RBs) in the DL system bandwidth, the PHICH configuration, and the System Frame Number (SFN). The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information not transmitted via the PBCH (e.g., System Information Block (SIB)), and paging messages.

[0045] like Figure 2C As shown, some REs carry demodulation reference signals (DM-RS) for channel estimation at the eNB. Additionally, the UE can transmit a sounding reference signal (SRS) in the last symbol of the subframe. This SRS can have a comb structure, and the UE can transmit the SRS on one of these combs. The eNB can use this SRS for channel quality estimation to implement frequency-dependent scheduling on the UL. Figure 2DExamples of various channels within a UL subframe of a frame are shown. The Physical Random Access Channel (PRACH) can be configured based on the PRACH and reside within one or more subframes of the frame. The PRACH can comprise six consecutive RB pairs within a subframe. The PRACH allows the UE to perform initial system access and achieve UL synchronization. The Physical Uplink Control Channel (PUCCH) can reside above the edge of the UL system bandwidth. The PUCCH carries uplink control information (UCI) such as scheduling requests, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and HARQ ACK / NACK feedback. The PUSCH carries data and can also be used to carry buffer status reports (BSR), power clearance reports (PHR), and / or UCI.

[0046] Figure 3 This is a block diagram illustrating the communication between eNB 310 and UE 350 in the access network. In the DL (Data Link Module), IP packets from EPC 160 are provided to the controller / processor 375. The controller / processor 375 implements Layer 3 and Layer 2 functions. Layer 3 includes the Radio Resource Control (RRC) layer, and Layer 2 includes the Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Media Access Control (MAC) layer. The controller / processor 375 provides: RRC layer functions associated with broadcasting system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), mobility between Radio Access Technologies (RATs), and measurement configuration for UE measurement reporting; PDCP layer functions associated with header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions associated with upper-layer packet data unit (PDU) transmission, error correction via ARQ, connection, segmentation, and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with mapping between logical channels and transport channels, multiplexing MAC SDUs onto transport blocks (TBs), demultiplexing MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority processing, and logical channel priority allocation.

[0047] Transmit (TX) processor 316 and receive (RX) processor 370 implement Layer 1 functions associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection of the transport channel, forward error correction (FEC) encoding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. TX processor 316 processes the mapping for the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase phase shift keying (M-PSK), and M-order quadrature amplitude modulation (M-QAM)). The encoded and modulated symbols can then be segmented into parallel streams. Each stream can then be mapped to OFDM subcarriers, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domains, and subsequently combined using an inverse Fourier transform (IFFT) to generate a physical channel carrying a stream of time-domain OFDM symbols. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from channel estimator 374 can be used to determine coding and modulation schemes and to implement spatial processing. The channel estimates can be derived from reference signals and / or channel condition feedback transmitted by UE 350. Subsequently, each spatial stream can be provided to a different antenna 320 via a separate transmitter 318TX. Each transmitter 318TX can use the respective spatial stream to modulate an RF carrier for transmission.

[0048] At UE 350, each receiver 354RX receives signals via its respective antenna 352. Each receiver 354RX recovers the information modulated onto the RF carrier and provides this information to the receive (RX) processor 356. The TX processor 368 and RX processor 356 implement Layer 1 functions associated with various signal processing functions. The RX processor 356 can perform spatial processing on the information to recover any spatial streams destined for UE 350. If multiple spatial streams are destined for UE 350, the RX processor 356 can combine them into a single OFDM symbol stream. Subsequently, the RX processor 356 uses a Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, along with the reference signal, are recovered and demodulated by determining the most probable signal constellation points transmitted by eNB 310. These soft decisions can be based on channel estimates calculated by channel estimator 358. These soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted by the eNB 310 on the physical channel. This data and control signals are then provided to the controller / processor 359, which implements Layer 3 and Layer 2 functions.

[0049] The controller / processor 359 can be associated with a memory 360 that stores program code and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels to recover IP packets from the EPC 160. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operation.

[0050] Similar to the functions described in the DL transmission combined with eNB 310, controller / processor 359 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 (encryption, decryption, integrity protection, integrity verification); RLC layer functions associated with upper-layer PDU transmission, error correction via ARQ, RLC SDU connection, segmentation and reassembly, RLC data PDU resegmentation, and RLC data PDU reordering; and MAC layer functions associated with mapping between logical channels and transport channels, MAC SDU multiplexing onto TB, demultiplexing MAC SDU from TB, scheduling information reporting, error correction via HARQ, priority processing, and logical channel priority allocation.

[0051] The channel estimate derived by channel estimator 358 from the reference signal or feedback transmitted by eNB 310 can be used by TX processor 368 to select appropriate coding and modulation schemes and facilitate spatial processing. The spatial stream generated by TX processor 368 can be provided to different antennas 352 via their respective transmitters 354TX. Each transmitter 354TX can use its own spatial stream to modulate the RF carrier for transmission.

[0052] The eNB 310 processes UL transmissions in a manner similar to that described in conjunction with the receiver function at UE 350. Each receiver 318RX receives signals via its respective antenna 320. Each receiver 318RX recovers the information modulated onto the RF carrier and provides that information to the RX processor 370.

[0053] The controller / processor 375 can be associated with a memory 376 that stores program code and data. The memory 376 can be referred to as a computer-readable medium. In the UL, the controller / processor 375 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels 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 ACK and / or NACK protocols to support HARQ operation.

[0054] Figure 4 This is a diagram of a device-to-device (D2D) communication system 460. The D2D communication system 460 includes multiple UEs 464, 466, 468, and 470. Furthermore, the D2D communication system 460 can overlap with a cellular communication system (e.g., WWAN). Some of the UEs 464, 466, 468, and 470 can communicate together using DL / UL WWAN spectrum and D2D communication, some can communicate with a base station 462, and some can perform both types of communication. For example, as... Figure 4 As shown, UEs 468 and 470 are in D2D communication, as are UEs 464 and 466. Furthermore, UEs 464 and 466 also communicate with base station 462. D2D communication can be conducted through one or more sidelink channels, such as the Physical Sidelink Broadcast Channel (PSBCH), Physical Sidelink Discovery Channel (PSDCH), Physical Sidelink Shared Channel (PSSCH), and Physical Sidelink Control Channel (PSCCH).

[0055] The exemplary methods and apparatuses discussed above are suitable for any of a wide variety of wireless D2D communication systems (e.g., wireless device-to-device communication systems based on FlashLinQ, WiMedia, Bluetooth, ZigBee, or Wi-Fi based on the IEEE 802.11 standard). For simplicity, these exemplary methods and apparatuses are discussed in the context of LTE. However, it will be understood by anyone skilled in the art that these exemplary methods and apparatuses are generally suitable for generalization to a wide variety of other wireless device-to-device communication systems.

[0056] D2D communication on licensed spectrum can be used to provide direct communication between devices. An example of D2D communication on licensed spectrum includes communication using LTE Direct (LTE-D). D2D communication enables one UE to communicate with another UE and send data to other UEs on allocated resources. For example, UEs located in the same network (e.g., in the same cell) or within a certain range of each other can communicate directly with each other on licensed spectrum via LTE-D. Furthermore, LTE-D can also be used to discover neighboring UEs within the same network. One application of D2D communication on licensed spectrum can be vehicle-to-vehicle (V2V) communication or vehicle-to-any-device (V2X) communication. In V2V communication, a UE in one vehicle can perform D2D communication with a UE in another vehicle on licensed spectrum. In V2X communication, a UE in a vehicle can perform D2D communication with another UE on licensed spectrum, regardless of whether the other UE is located within the vehicle.

[0057] During V2V communication (or V2X communication or D2D communication), a UE wishing to communicate with another UE can transmit control channels and data channels. Control and data channels can share a communication resource pool; for example, some resources are allocated to the control channel, and the remaining resources are allocated to the data channel. This control channel can be a Physical Sidelink Control Channel (PSCCH). The control channel can also be called a Scheduling Allocation (SA) channel because it carries scheduling allocations. Each SA can indicate an MCS value and the location of resources in the data channel used for transmitting data. The sending UE can transmit encoded data to another UE on the data channel. The data channel can be transmitted after the control channel. This data channel can be a Physical Sidelink Shared Channel (PSSCH). When a UE wants to receive data from the sending UE, it can decode the control channel transmitted by the sending UE to determine the resources used by the sending UE to transmit data (e.g., where in the data channel to look up the data). Furthermore, the receiving UE can also determine the MCS used for demodulating / decoding the data based on the MCS value indicated in the control channel. Therefore, based on the information in the control channel, the receiving UE can locate the data in the resources configured for D2D communication and then decode the data in the data channel.

[0058] Compared to stationary devices, UEs located in vehicles may experience more rapidly changing channel conditions because the channel conditions observed by a UE in a vehicle are affected by the vehicle's speed. Therefore, if the vehicle is traveling at high speed, the UE in the vehicle is also traveling at high speed. At high speeds, the surrounding environment of the device may change more rapidly; for example, the amount of reflections, the number of nearby objects, and Doppler diffusion change more quickly, which in turn causes the communication channel conditions to change more rapidly. Rapidly changing channel conditions can lead to less reliable channel estimation and reduce the reliability of channel decoding by the receiving UE. This disclosure relates to techniques for D2D (or V2V / V2X) communication when the UE's speed is high (e.g., 250 km / h to 500 km / h). This D2D (or V2V / V2X) communication can occur on licensed or unlicensed spectrum.

[0059] Figure 5 This is a diagram illustrating an example of a V2V communication system 500. A first UE 512 is present in a first vehicle 510 and therefore can travel with the first vehicle 510. A second UE 532 may be present in a second vehicle 530, or it may exist independently without the second vehicle 530. The first UE 512 and the second UE 532 may be connected to a base station 550. The first UE 512 and the second UE 532 may be configured to perform D2D communication (e.g., V2V communication or V2X communication) with each other. This D2D communication may occur on licensed spectrum or unlicensed spectrum. In the V2V communication system 500, at 562, the first UE 512 sends data to the second UE 532. Therefore, the first UE 512 may be referred to as the sending UE, and the second UE 532 may be referred to as the receiving UE.

[0060] According to one aspect of this disclosure, when a transmitting UE (e.g., first UE 512) is traveling at high speed, the channel estimation used by a receiving UE (e.g., second UE 532) during channel decoding (e.g., control channel or data channel) can be improved by increasing the redundancy in the channels transmitted by the transmitting UE. Specifically, the transmitting UE can estimate its travel speed (e.g., absolute or relative travel speed) and determine its transmission configuration based on that speed. In one aspect, the transmitting UE can adjust the transmission configuration such that more redundancy is transmitted in these channels if the transmitting UE is traveling at high speed. The transmission configuration may include at least one of the following: an MCS value (e.g., modulation order and / or coding rate), the number of RBs used by the transmitting UE for each (HARQ) transmission, and the number of (HARQ) retransmissions by the transmitting UE. For example, if the transmitting UE's travel speed is high, the transmission configuration may be determined to have a lower MCS value and / or the transmitting UE may use a higher number of RBs and / or a higher number of retransmissions. For example, if the sending UE's speed is low, it can be determined that the transmission configuration has a higher MCS value and / or the sending UE uses a lower number of RBs and / or a lower number of retransmissions. For instance, when the travel speed exceeds a certain threshold, the sending UE can determine that the travel speed is high, and when the travel speed does not exceed that threshold, the sending UE can determine that the travel speed is low. For example, when the travel speed increases to exceed a high threshold, the sending UE can determine that the travel speed is high, and when the travel speed decreases to below a low threshold, it can determine that the travel speed is low. A range of travel speeds can be associated with a certain transmission configuration. That is, different ranges of travel speeds can be associated with different transmission configurations. The association between a travel speed and the corresponding transmission configuration can be pre-configured and / or can be transmitted by the network (e.g., eNB).

[0061] The transmission configuration can include an SA transmission configuration and a data transmission configuration. Both the SA transmission configuration and the data transmission configuration can be determined based on the sending UE's travel speed. The sending UE can transmit a control channel based on the SA transmission configuration. The control channel can transmit information about the data transmission configuration. The sending UE can transmit a data channel based on the data transmission configuration. Furthermore, after decoding the control channel received from the sending UE, the receiving UE can receive a data channel from the sending UE based on the data transmission configuration transmitted in the control channel.

[0062] The transmitting UE can determine the driving speed based on its absolute driving speed and / or the characteristics of the area where it is located. In one aspect, the driving speed can be an estimated speed by the transmitting UE or a speedometer reading of the vehicle. In another aspect, the transmitting UE can determine the maximum speed in the area corresponding to its location based on the area's speed limits, wherein the transmitting UE's location can be estimated by a location sensor such as a Global Positioning System (GPS) device. For example, if the speed limit on the road where the transmitting UE is located is 50 km / h, then the transmitting UE can determine that its driving speed is 50 km / h. In another aspect, the transmitting UE can determine whether the area corresponding to its location is a high-speed area (e.g., a highway) or a low-speed area (e.g., a local road). If it is determined that the transmitting UE is located in a high-speed area, then the transmitting UE can determine a higher driving speed. If it is determined that the transmitting UE is located in a low-speed area, then the transmitting UE can determine a lower driving speed.

[0063] In one respect, the sending UE can receive information from a network (e.g., an LTE network or some other WWAN). This network can transmit rate limiting information based on the sending UE's current location. The UE's location can be determined based on GPS location information transmitted by the sending UE, or based on signals received from the sending UE at a base station.

[0064] For example, in a typical configuration, when moving at a low or medium speed, the transmitting UE can transmit 300 bytes of data over 20 RBs. If the transmitting UE is traveling at a higher speed, a lower MCS can be used to transmit 300 bytes of data, thus utilizing more resources (e.g., 50 RBs). For example, in a typical configuration, when the transmitting UE is moving at a low or medium speed, an SA transmission can be performed on one RB (e.g., via the control channel). If the transmitting UE is traveling at a higher speed, redundancy can be increased by repeating the SA transmission over two RBs. With sufficient redundancy, the receiving UE can successfully decode both the control and data channels, even if the receiving UE does not have a good estimate of the channel conditions (due to the higher travel speed). For example, if the transmitting UE determines that it has entered a high-speed area and / or is moving at a high speed (over 140 km / h), and therefore its travel speed is high, the transmitting UE can use a lower MCS to transmit the same amount of data (e.g., 300 bytes) (e.g., over 50 RBs instead of 20 RBs).

[0065] Figure 6Example Figure 600 illustrates the error rates experienced by the UE under various scenarios. Example Figure 600 shows the block error rate versus signal-to-noise ratio (SNR) in V2V communication between the sending UE and the receiving UE when the sending UE is traveling at a speed of 250 km / h. Example Figure 600 shows that at high speeds such as 250 km / h, using a typical MCS (e.g., transmitting 300 bytes on 20 RBs) may result in a high block error rate (BLER) at the receiving UE, regardless of the SNR at the receiving UE. For example, according to this example Figure 600, at 250 km / h, achieving a lower BLER of 10% may be difficult if a typical MCS (e.g., transmitting 300 bytes of data on 20 RBs) is used, regardless of whether a decision feedback (DF) algorithm is used. However, as shown in example Figure 600, at 250 km / h, if 50 RBs (e.g., corresponding to a lower MCS) are used to send 300 bytes of data, a lower BLER of 10% can be achieved at 2.5 dB SNR when using the DF algorithm, and a lower BLER of 10% can be achieved at 5 dB SNR when not using the DF algorithm.

[0066] The complexity for the receiving UE may increase if different SA transmission configurations are used to transmit the SA channel. For example, the number of assumptions (possible combinations of available control channel resources) that the receiving UE must test to decode the control channel may increase (e.g., non-linearly) with the number of transmission configurations used. For example, if the available SA resource pool has 20 RBs per subframe, and a typical SA transmission is performed on 1 RB, and a high-speed SA transmission is performed on 2 RBs, then for each subframe, there may be 20 different assumptions (20 different possible combinations) for the typical SA transmission, and 10 different assumptions for the high-speed SA transmission. In this example, the possibilities could be RB#0, RB#1, RB#2, ..., RB#19 for the typical SA transmission, and RBs#0#1, RBs#2#3, RBs#4#5, ..., RBs#18#19. Therefore, in this example, there could be a total of 30 possible assumptions per subframe. Therefore, methods to reduce the complexity of channel decoding are desired.

[0067] According to one aspect of this disclosure, available SA resources can be divided into multiple SA resource sets (e.g., N sets) based on transmission configuration. These SA resources can be reserved for control channel transmission, and each UE in the system can use the same SA resources to transmit control channels. Therefore, a UE wanting to receive communication from another UE can attempt to decode the control channels in the SA resources based on this assumption. In one aspect, the first resource set can have a fixed transmission configuration, allowing the presence of control channels in the first SA resource set to be detected using blind decoding. The first SA resource set can be used for typical transmission configurations, such as low to medium speeds for coexistence with legacy equipment.

[0068] The size of each SA resource set can depend on the travel speed of the sending UE. Furthermore, the type of SA transmission configuration associated with each SA resource set can also depend on the travel speed of the sending UE. Different SA resource sets can correspond to different travel speeds. The size and SA transmission configuration for each SA resource set can be fixed, pre-configured for the corresponding area, or transmitted by the network (e.g., by the eNB).

[0069] In one aspect, a first set of multiple SA resource sets can be used to communicate with a fixed SA transmission configuration (e.g., fixed MCS and resource size) and may not be used to communicate with other types of SA transmission configurations. The first SA resource set can be used when the SA transmission configuration does not change based on the sending UE's travel speed. The sending UE can use other SA resource sets (excluding the first set) to communicate using a configuration that changes according to the sending UE's travel speed. Therefore, other SA resource sets can be used when the sending UE is traveling at high speed. Thus, if the sending UE determines to use a fixed SA transmission configuration, the sending UE can use any of the multiple SA resource sets to transmit control channels. If the sending UE determines to change the SA transmission configuration based on its speed, the sending UE can use an SA resource set different from the first SA resource set to transmit control channels. In one configuration, the SA resource set used may correspond to the sending UE's speed.

[0070] Figure 7Figure 700 illustrates an example SA resource according to one aspect of this disclosure. In this example, the SA resource may include 10 subframes numbered 0 to 9. Each subframe may include a fixed number of resource blocks (e.g., 12 RBs). As shown in Figure 700, the SA resource can be divided into three SA resource sets, namely set 1, set 2, and set 3. Set 1 includes the RBs corresponding to subframe numbers 0 and 1, set 2 includes the RBs corresponding to subframe numbers 2, 3, 4, and 5, and set 3 includes the RBs corresponding to subframe numbers 6, 7, 8, and 9. Set 1 may be dedicated to a fixed SA transmission configuration. Set 2 may be used to transmit an SA transmission configuration when the sending UE is traveling at a medium speed, or it may be used to transmit a fixed SA transmission configuration. Set 3 may be used to transmit an SA transmission configuration when the sending UE is traveling at a high speed, or it may be used to transmit a fixed SA transmission configuration. Therefore, if the sending UE determines to use a typical configuration with a fixed SA transmission configuration, the sending UE can use any of set 1, set 2, and set 3 to transmit the control channel. If the sending UE determines to use a changing configuration based on its travel speed, the sending UE can use either set 2 or set 3 to transmit the control channel, depending on its travel speed. In one aspect, the sending UE can use set 1 for the typical configuration of SA transmission mode to reduce complexity at the receiving UE.

[0071] The receiving UE can receive transmissions from various sending UEs. The receiving UE can determine which SA resource set the sending UE uses to transmit the control channel. If the receiving UE receives communication from the sending UE within one of the multiple SA resource sets, the receiving UE can attempt to decode the control channel based on the SA transmission configuration used for the control channel from that SA resource set (e.g., through blind decoding). Since the receiving UE does not attempt decoding based on the entire SA resource set, but only on a subset of SA resources, the decoding complexity is reduced. Furthermore, for example, set 1 can be dedicated to a fixed SA transmission configuration, thus limiting the assumptions used for set 1 to a fixed SA transmission configuration, which further reduces decoding complexity. When decoding the control channel, the receiving UE can determine the data transmission configuration based on that control channel. Subsequently, the receiving UE can receive data from the sending UE based on that data transmission configuration. For example, see... Figure 7 In the example, if the receiving UE determines to use set 1 to transmit the SA, the receiving UE can attempt to decode the control channel based on a fixed SA transmission configuration from set 1, instead of attempting to decode based on set 2 or set 3. See, for example, [link to example]. Figure 7In the example, if the receiving UE determines to use set 3 to transmit the SA, the receiving UE can attempt to decode the control channel based on a fixed SA transmission configuration, or it can attempt to decode the control channel based on an SA transmission configuration from set 3 for high driving speeds. In this example, if the sending UE uses a varying configuration based on the transmission, the receiving UE can ultimately decode the control channel based on the SA transmission configuration for high driving speeds. If the sending UE uses a fixed configuration, the receiving UE can ultimately decode the control channel based on the fixed SA transmission configuration.

[0072] In one configuration, a fixed SA transmission configuration for a typical setup can be specified based on a scenario (e.g., geographical region). For example, where speeds are typically low to medium in urban areas, this fixed SA transmission configuration could correspond to the sending UE moving at low to medium speeds. Similarly, where speeds are typically high on rural roads, this fixed SA transmission configuration could correspond to the sending UE moving at high speeds.

[0073] Figure 8 According to one aspect of this disclosure, a flowchart 800 of a wireless communication method is shown. This method can be performed by a UE (e.g., UE 104, first UE 512, device 1202 / 1202').

[0074] At point 802, the UE can determine its travel speed. In one aspect, the travel speed can be determined based on at least one of the UE's existing travel speed or a maximum travel speed corresponding to the UE's location. In another aspect, the maximum travel speed corresponding to the UE's location can be determined by determining the UE's location and then determining the maximum travel speed corresponding to that location. In another aspect, the maximum travel speed corresponding to the UE's location is a speed limit for the area corresponding to the UE's location. In yet another aspect, the travel speed can also be determined based on the travel speed of the receiving UE.

[0075] At point 804, the UE can determine its transmission configuration for device-to-device communication based on its travel speed. This D2D communication can be V2V or V2X communication. The device-to-device communication can occur on licensed or unlicensed spectrum. In one aspect, the transmission configuration may include at least one of the following: MCS, the number of resource blocks for transmission, and the number of retransmissions. In another aspect, the association information between the travel speed and the corresponding transmission configuration may be pre-configured or received from the base station.

[0076] In one aspect, when the UE's travel speed increases, the UE can adjust its transmission configuration by performing at least one of the following: increasing the number of resource blocks used for transmission; decreasing the modulation and coding scheme (MCS) value; or increasing the number of retransmissions. In another aspect, when the UE's travel speed decreases, the UE can adjust its transmission configuration by performing at least one of the following: decreasing the number of resource blocks used for transmission; increasing the MCS value; or decreasing the number of retransmissions.

[0077] At point 806, the UE can transmit device-to-device communication based on the transmission configuration. In one aspect, the UE can transmit an SA based on an SA transmission configuration and transmit data via a data channel based on a data transmission configuration. In this aspect, the SA indicates the data transmission configuration and the location of resources in the data channel used for transmitting data.

[0078] In one aspect, a UE can transmit device-to-device communication in the following manner: if the UE determines to use a fixed SA transmission configuration, it transmits the SA on any of a plurality of SA resource sets; if the UE determines to change its SA transmission configuration based on its travel speed, it transmits the SA on a corresponding SA resource set different from the first SA resource set. Available SA resources can be allocated to the plurality of SA resource sets based on the type of SA transmission configuration. In this aspect, the first SA resource set can be associated with a fixed SA transmission configuration, and each of the other SA resource sets can be associated with a corresponding type of SA transmission configuration and a fixed SA transmission configuration. In this aspect, the size of each SA resource set and at least one type of SA transmission configuration for each SA resource set can be associated with the corresponding travel speed of the UE. In this aspect, the size of each SA resource set or at least one of the at least one type of SA transmission configuration for each SA resource set can be pre-configured or received from a base station.

[0079] Figure 9 According to one aspect of this disclosure, a flowchart 900 of a method for wireless communication is shown. This method can be performed by a UE (e.g., UE 104, a second UE 532, device 1202 / 1202').

[0080] At 902, the UE can receive communication from the sending UE via device-to-device communication. This device-to-device communication can occur on licensed spectrum or unlicensed spectrum.

[0081] At position 904, the UE can determine the appropriate SA resource set from among multiple SA resource sets for receiving communication from the sending UE. The available SA resources can be allocated into these multiple SA resource sets based on the type of SA transport configuration.

[0082] At 906, the UE can decode the SA based on communication within the corresponding SA resource set. In one aspect, the UE can decode the SA indicating a data transmission configuration by performing blind decoding within the corresponding SA resource set. In another aspect, if the corresponding SA resource set is a first SA resource set, the UE can decode the SA based on a fixed SA configuration; and if the corresponding SA resource set is a different set from the first set, the UE can decode the SA based on a fixed SA configuration, or decode the SA based on an SA transmission configuration corresponding to the corresponding SA resource set.

[0083] At 908, the UE can determine the data transmission configuration based on the SA in the corresponding SA resource set.

[0084] At point 910, the UE can receive data from the sending UE based on the data transmission configuration. In one aspect, the data transmission configuration includes at least one of the following: MCS, the number of resource blocks for transmission, and the number of retransmissions.

[0085] In one aspect, the UE can receive data transmission by determining the location of resources in the data channel based on the SA, and receiving data transmission based on the location of the resources and the data transmission configuration. In another aspect, the size of each SA resource set and at least one type of SA transmission configuration for each SA resource set can be associated with the corresponding travel speed of the sending UE. In this aspect, the size of each SA resource set or at least one of the at least one type of SA transmission configuration for each SA resource set can be pre-configured or received from the base station.

[0086] Wireless networks can use Zadoff-Chu sequences to orthogonalize or pseudo-orthogonalize wireless signals. A Zadoff-Chu sequence is a complex-valued mathematical sequence that can be applied to wireless signals, resulting in signals with essentially constant amplitude. Furthermore, when received by a receiver, a cyclically shifted version of the Zadoff-Chu sequence is pseudo-orthogonal to the wireless signal. The resulting Zadoff-Chu sequence without cyclic shifting serves as the root index. In one configuration, each root sequence can be identified by a unique root index.

[0087] In one configuration, a subframe for D2D (or V2V / V2X) communication may include multiple DM-RS symbols. Some of these DM-RS symbols may reside in the control channel (e.g., PSCCH) of the subframe. Some of these DM-RS symbols may reside in the data channel (e.g., PSSCH) of the subframe. A Zadoff-Chu sequence may be transmitted in each DM-RS symbol of the subframe. This Zadoff-Chu sequence may be referred to as a DM-RS sequence. In one configuration, a DM-RS sequence may refer to a sequence different from a Zadoff-Chu sequence. In one configuration, group hopping may be enabled for the DM-RS sequence of the control channel, such that different DM-RS sequences are transmitted on different DM-RS symbols in the control channel. In one configuration, group hopping may refer to hopping or changing the root index of the Zadoff-Chu sequence used for different DM-RS symbols. In one configuration, enabling group switching for DM-RS symbols in subframes can resolve or mitigate timing / frequency ambiguity issues encountered by vehicle D2D devices.

[0088] Figure 10 Figure 1000 illustrates an example of enabling group hopping for DM-RS symbols in a subframe. In this example, a subframe for D2D (or V2V / V2X) communication may include four DM-RS symbols 1002, 1004, 1006, and 1008. DM-RS symbols 1002, 1004, 1006, and 1008 are located in the control channel (e.g., PSCCH) of D2D or V2V / V2X communication.

[0089] In one configuration, group hopping can be enabled for DM-RS symbols in the control channel. In this configuration, the root indexes of the Zadoff-Chu sequences for DM-RS symbols 1002, 1004, 1006, and 1008 can be different.

[0090] In one configuration, the DM-RS sequence for each DM-RS symbol in the control channel can be determined at least in part based on the group hopping pattern. In one configuration, the group hopping pattern can be a pattern of different root indices of the Zadoff-Chu sequences for different DM-RS symbols. In one configuration, the group hopping pattern can be determined based on the different root indices of the Zadoff-Chu sequences for different DM-RS symbols.

[0091] In one configuration, the root index of the Zadoff-Chu sequence for a DM-RS symbol may depend on a time resource index. This time resource index may refer to either the slot index or the symbol index of the DM-RS symbol. For example, the root index of the Zadoff-Chu sequence for DM-RS symbol 1002 may depend on either the slot index (e.g., "0") or its symbol index (e.g., "2") of DM-RS symbol 1002; and the root index of the Zadoff-Chu sequence for DM-RS symbol 1006 may depend on either the slot index (e.g., "1") or its symbol index (e.g., "8").

[0092] In one configuration, the root index of the Zadoff-Chu sequence for a DM-RS symbol may depend on the frequency resource index used by the corresponding control channel (in the scheduling allocation resource pool). For example, the root index of the Zadoff-Chu sequence for DM-RS symbol 1002 may depend on the index of the first resource block (RB) used by the PSCCH of that subframe. Similarly, the root index of the Zadoff-Chu sequence for DM-RS symbol 1004 may depend on the index of the first RB used by the PSCCH of that subframe.

[0093] In one configuration, the root index of the Zadoff-Chu sequence used for the DM-RS symbol can depend on an identifier. This identifier can be determined at least in part based on the SA identifier associated with the D2D or V2V / V2X communication. This identifier can provide some randomization relative to DM-RS transmissions potentially interfering from different UEs. In another configuration, this identifier can be fixed.

[0094] In one configuration, a UE in D2D or V2V / V2X communication can determine whether to enable or disable group hopping for a DM-RS symbol in the control channel (e.g., PSCCH) based on one or more of the following: the UE's speed, pre-configuration, or signaling from the eNB. For example, the UE can enable group hopping for a DM-RS symbol in the control channel when its speed is faster than or equal to a threshold (e.g., 140 km / h), and disable group hopping for a DM-RS symbol in the control channel when its speed is slower than the threshold. The UE can use the above references Figure 5 The described method is used to determine its speed.

[0095] In one configuration, a UE in D2D or V2V / V2X communication can apply a group hopping mode to DM-RS symbols in a data channel (e.g., PSSCH). In one configuration, the group hopping mode applied to DM-RS symbols in the data channel can be similar to the group hopping mode described above for DM-RS symbols in the control channel. In one configuration, the group hopping mode applied to DM-RS symbols in the data channel can depend on the symbol index of the DM-RS symbol. Using the symbol index of the DM-RS symbol to determine the root index of the Zadoff-Chu sequence for that DM-RS symbol can make it highly likely that all DM-RS symbols transmitted in that subframe are different (e.g., using different root indices). In one configuration, the group hopping mode applied to DM-RS symbols in the data channel can depend on the slot index of the DM-RS symbol.

[0096] Figure 11 According to one aspect of this disclosure, a flowchart 1100 of a wireless communication method is shown. Specifically, the figure illustrates a method for enabling group hopping for DM-RS symbols in a control channel used for D2D or V2V / V2X communication. This method can be performed by a UE (e.g., UE 104, first UE 512, second UE 532, or device 1202 / 1202').

[0097] At 1102, the UE can determine the enable group transition for multiple DM-RS sequences associated with a control channel (e.g., PSCCH) used for device-to-device communication. These multiple DM-RS sequences can be carried on multiple DM-RS symbols (e.g., 1002, 1004, 1006, and 1008) in the control channel of the subframe. In one configuration, the determination of the enable group transition can be based on one or more of the following: the UE's travel speed, pre-configuration, or eNB signaling. In one configuration, different DM-RS sequences can be carried on different DM-RS symbols.

[0098] At 1104, the UE can determine the plurality of DM-RS sequences by applying a group hopping mode to the plurality of DM-RS symbols. In one configuration, the plurality of DM-RS sequences can be generated based on the Zadoff-Chu sequence. In another configuration, in order to apply the group hopping mode to the plurality of DM-RS symbols, the UE changes the root index of the Zadoff-Chu sequence used for different DM-RS symbols.

[0099] In one configuration, the root index for the Zadoff-Chu sequence of the DM-RS symbol among the plurality of DM-RS symbols may be determined based on a time resource index. In one configuration, the time resource index may be either a slot index or a symbol index of the DM-RS symbol. In one configuration, the root index for the Zadoff-Chu sequence of the DM-RS symbol may be further determined based on a frequency resource index used by the control channel. In one configuration, the root index for the Zadoff-Chu sequence of the DM-RS symbol may be further determined based on an identifier. In one configuration, the identifier may be determined at least in part based on a scheduling allocation identifier associated with device-to-device communication. In another configuration, the identifier may be a fixed identifier.

[0100] At 1106, the UE can send or receive scheduling allocations for device-to-device communication, along with the plurality of DM-RS sequences.

[0101] At 1108, the UE may optionally determine a second plurality of DM-RS sequences associated with a data channel (e.g., PSSCH) used for device-to-device communication by applying a second set of hopping patterns to a second plurality of DM-RS symbols in the data channel of the subframe. In one configuration, the second plurality of DM-RS sequences may be generated based on a Zadoff-Chu sequence. In one configuration, to apply the second set of hopping patterns to the second plurality of DM-RS symbols, the UE may change the root index of the Zadoff-Chu sequence for different DM-RS symbols. In one configuration, the root index of the Zadoff-Chu sequence for the DM-RS symbols in the second plurality of DM-RS symbols may be determined based on the slot index of the DM-RS symbols.

[0102] At 1110, the UE may optionally use the second plurality of DM-RS sequences to send or receive data for device-to-device communication.

[0103] Figure 12 This is a conceptual data flow diagram 1200 illustrating the data flow between different units / components in an exemplary device 1202. The device may be a UE (User Equipment). The device includes a receiving component 1204, a transmission component 1206, a travel speed component 1208, a transmission configuration component 1210, a communication management component 1212, a decoding component 1214, and a group hopping component 1216. Device 1202 and a second UE 1240 may be connected to base station 1250 at locations 1262, 1264, and 1266.

[0104] According to one aspect, device 1202 may be a UE that transmits or receives communications to or from other devices (e.g., second UE 1240). In this aspect, travel speed component 1208 may determine the travel speed of device 1202. At 1268, travel speed component 1208 may transmit information about the travel speed to transmission configuration component 1210. At 1284, travel speed component 1208 may transmit information about the travel speed to group switching component 1216. In one aspect, the travel speed may be determined based on at least one of the travel speed of device 1202 or the maximum travel speed corresponding to the location of device 1202. In one aspect, travel speed component 1208 may determine the maximum travel speed corresponding to the location of device 1202 by determining the location of device 1202 and determining the maximum travel speed corresponding to the location of device 1202. In one aspect, the maximum travel speed corresponding to the location of device 1202 may be a speed limit of the area corresponding to the location of device 1202. In one aspect, the driving speed can also be determined based on the driving speed of the receiving UE (e.g., UE 1240).

[0105] The transmission configuration component 1210 can determine the transmission configuration of the device 1202 for device-to-device communication based on the UE's travel speed. This device-to-device communication can occur on licensed or unlicensed spectrum. At 1270, the transmission configuration component 1210 can transmit information about the transmission configuration to the communication management component 1212. In one aspect, the transmission configuration may include at least one of the following: MCS, the number of resource blocks used for transmission, and the number of retransmissions. In one aspect, the association information between the travel speed and the corresponding transmission configuration may be pre-configured or received from a base station (e.g., base station 1250).

[0106] In one aspect, when the travel speed of device 1202 increases (e.g., according to travel speed component 1208), transmission configuration component 1210 can adjust the transmission configuration of the UE by performing at least one of the following: increasing the number of resource blocks used for transmission, decreasing the modulation and coding scheme (MCS) value, or increasing the number of retransmissions. In another aspect, when the travel speed of the UE decreases (e.g., according to travel speed component 1208), transmission configuration component 1210 can adjust the transmission configuration of the UE by performing at least one of the following: decreasing the number of resource blocks used for transmission, increasing the MCS value, or decreasing the number of retransmissions.

[0107] Group hopping component 1216 can enable or disable group hopping based on the UE's travel speed and for DM-RS symbols in the control channel used for device-to-device communication. At 1286, group hopping component 1216 can transmit information about the group hopping to communication management component 1212. In one aspect, enabling / disabling group hopping can be pre-configured or received from a base station (e.g., base station 1250).

[0108] In one aspect, when the UE's travel speed increases (e.g., according to travel speed component 1208), group switching component 1216 can enable group switching. In another aspect, when the UE's travel speed decreases (e.g., according to travel speed component 1208), group switching component 1216 can disable group switching.

[0109] At 1272 and 1274, the communication management component 1212 can send device-to-device communication via the transmission component 1206 based on the transmission configuration (e.g., for the second UE 1240) and / or group transition configuration (e.g., enabled or disabled).

[0110] In one aspect, the communication management component 1212 can transmit device-to-device communication via the transmission component 1206 by sending an SA based on an SA transmission configuration, and can transmit data via a data channel based on a data transmission configuration. In this aspect, the SA can indicate the data transmission configuration and the location of resources used for the data channel.

[0111] In one aspect, the communication management component 1212 can transmit device-to-device communication via the transmission component 1206 in the following manner: if the communication management component 1212 determines to use a fixed SA transmission configuration, it transmits the SA on any of a plurality of SA resource sets; if the communication management component 1212 determines to change the SA transmission configuration of the UE based on the UE's travel speed, it transmits the SA on a corresponding SA resource set different from the first SA resource set. SA resources can be divided into the plurality of SA resource sets based on the type of SA transmission configuration. In this aspect, the first SA resource set can be associated with a fixed SA transmission configuration, and each of the other SA resource sets can be associated with a corresponding type of SA transmission configuration and a fixed SA transmission configuration. In this aspect, the size of each SA resource set and at least one type of SA transmission configuration for each SA resource set can be associated with the corresponding travel speed of the UE. In this aspect, the size of each SA resource set or at least one of the at least one type of SA transmission configuration for each SA resource set can be pre-configured or received from a base station (e.g., base station 1250).

[0112] According to one aspect, apparatus 1202 may be a receiving UE for receiving communications from a sending UE. In this aspect, at 1276 and 1278, communication management component 1212 may receive communications from a sending UE (e.g., a second UE 1240) via receiving component 1204 through device-to-device communication.

[0113] Communication management component 1212 can determine, among multiple SA resource sets, the appropriate SA resource set for receiving communication from the transmitting UE (e.g., second UE 1240). SA resources can be allocated into the multiple SA resource sets based on the type of SA transport configuration. At 1280, communication management component 1212 can transmit information about the appropriate SA resource set to decoding component 1214. In one configuration, communication management component 1212 can perform channel estimation based on a DM-RS sequence received from group hopping component 1216.

[0114] Decoding component 1214 can decode the SA based on communication within the corresponding SA resource set. At 1282, decoding component 1214 can transmit information about the SA to transmission configuration component 1210.

[0115] In one aspect, the decoding component 1214 can decode the SA by performing blind decoding on the corresponding SA resource set to decode the SA indicating the data transmission configuration.

[0116] In one aspect, if the corresponding SA resource set is a first SA resource set, the decoding component 1214 can decode an SA based on a fixed SA configuration; if the corresponding SA resource set is an SA resource set different from the first set, it can decode an SA based on a fixed SA configuration or an SA based on an SA transmission configuration corresponding to the corresponding SA resource set.

[0117] The transmission configuration component 1210 can determine the data transmission configuration based on the SA in the corresponding SA resource set. At 1970, the transmission configuration component 1210 can transmit information about the data transmission configuration to the communication management component 1212.

[0118] At 1276 and 1278, the communication management component 1212 can receive data from the sending UE (e.g., the second UE 1240) via the receiving component 1204 based on the data transmission configuration.

[0119] In one aspect, the data transfer configuration may include at least one of the following: MCS, the number of resource blocks for transfer, and the number of retransmissions.

[0120] In one aspect, the communication management component 1212 may receive data (e.g., from the second UE 1240) by determining the location of resources for the data channel based on the SA, and receiving data based on the location of the resources for the data channel and the data transmission configuration.

[0121] In one aspect, the size of each SA resource set and at least one type of SA transmission configuration for each SA resource set may be associated with the corresponding travel speed of the sending UE (e.g., the second UE 1240). In this aspect, the size of each SA resource set or at least one of the at least one type of SA transmission configuration for each SA resource set may be pre-configured or received from the base station.

[0122] The device may include means for performing Figure 8 , 9 and Figure 11 The other components of each box in the algorithm of the aforementioned flowchart. Therefore, Figure 8 , 9 and Figure 11 Each block in the aforementioned flowchart can be executed by a component, and the apparatus may include one or more of these components. These components may be one or more hardware parts specifically configured to perform the stated processing / algorithm, implemented by a processor configured to perform the stated processing / algorithm, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

[0123] Figure 13 Figure 1300 illustrates an example of a hardware implementation of a device 1202' using processing system 1314. Processing system 1314 can be implemented using a bus architecture, typically denoted as bus 1324. Depending on the specific application and overall design constraints of processing system 1314, bus 1324 may include any number of interconnected buses and bridges. Bus 1324 will link together various circuits including one or more processors and / or hardware components (denoted as processor 1304, component 1204, 1206, 1208, 1210, 1212, 1214, 1216), and computer-readable medium / memory 1306. Furthermore, bus 1324 may also link various other circuits such as clock sources, peripheral devices, voltage regulators, and power management circuitry, which are well known in the art and therefore not described further.

[0124] Processing system 1314 may be coupled to transceiver 1310. Transceiver 1310 is coupled to one or more antennas 1320. Transceiver 1310 provides a unit for communicating with various other devices via a transmission medium. Transceiver 1310 receives signals from the one or more antennas 1320, extracts information from the received signals, and provides the extracted information to processing system 1314 (specifically, receiving component 1204). Furthermore, transceiver 1310 also receives information from processing system 1314 (specifically, transmission component 1206) and, based on the received information, generates signals to be applied to the one or more antennas 1320. Processing system 1314 includes processor 1304 coupled to computer-readable medium / memory 1306. Processor 1304 is responsible for general processing, including executing software stored on computer-readable medium / memory 1306. When the software is executed by processor 1304, processing system 1314 performs the various functions described above for any particular device. The computer-readable medium / memory 1306 can also be used to store data manipulated when the processor 1304 executes software. Furthermore, the processing system 1314 includes at least one of components 1204, 1206, 1208, 1210, 1212, 1214, and 1216. These components may be software components running in the processor 1304, residing in / stored in the computer-readable medium / memory 1306, one or more hardware components coupled to the processor 1304, or some combination thereof. The processing system 1314 may be a component of the UE 350, which may include memory 360 and / or at least one of TX processor 368, RX processor 356, and controller / processor 359.

[0125] In one configuration, the apparatus 1202 / 1202' for wireless communication may include: a unit for determining the travel speed of the UE; a determining unit for determining a transmission configuration of the UE for device-to-device communication based on the travel speed of the UE; and a unit for transmitting the device-to-device communication based on the transmission configuration. In one aspect, when the travel speed of the UE increases, the determining unit may be configured to perform at least one of the following: increasing the number of resource blocks used for transmission; decreasing the MCS value; or increasing the number of retransmissions. In one aspect, when the travel speed of the UE decreases, the determining unit may be configured to perform at least one of the following: decreasing the number of resource blocks used for transmission; increasing the MCS value; or decreasing the number of retransmissions. In one aspect, the unit for transmitting device-to-device communication may be configured to: transmit SA based on the SA transmission configuration; and transmit data via a data channel based on the data transmission configuration. In one aspect, the unit for transmitting device-to-device communication can be configured to: if the UE determines to use a fixed SA transmission configuration, then transmit SA on any of a plurality of SA resource sets; if the UE determines to change its SA transmission configuration based on its travel speed, then transmit SA on a corresponding SA resource set different from the first SA resource set, wherein the SA resources are divided into the plurality of SA resource sets based on the type of the SA transmission configuration.

[0126] In another configuration, the apparatus 1202 / 1202' for wireless communication may include: a unit for receiving communication from a transmitting UE via device-to-device communication; a unit for determining, among a plurality of SA resource sets, a corresponding SA resource set for receiving communication from the transmitting UE, wherein the SA resources are allocated to the plurality of SA resource sets based on the type of SA transmission configuration; a unit for decoding SAs based on communication in the corresponding SA resource set; a unit for determining a data transmission configuration based on the SAs in the corresponding SA resource set; and a unit for receiving data from the transmitting UE based on the data transmission configuration. In one aspect, the unit for decoding SAs may be configured to perform blind decoding in the corresponding SA resource set to decode SAs indicating the data transmission configuration. In one aspect, a unit for decoding an SA can be configured to: decode an SA based on a fixed SA configuration if the corresponding SA resource set is a first SA resource set; and decode an SA based on the fixed SA configuration, or decode an SA based on an SA transmission configuration corresponding to the corresponding SA resource set, if the corresponding SA resource set is an SA resource set different from the first SA resource set. In another aspect, a unit for receiving data can be configured to: determine the location of resources for a data channel based on the SA, and receive the data based on the location of the resources for the data channel and the data transmission configuration.

[0127] In one configuration, the apparatus 1202 / 1202' for wireless communication may include: a unit for determining group hopping enabled for a plurality of DM-RS sequences associated with a control channel for device-to-device communication; a unit for determining the plurality of DM-RS sequences by applying a group hopping mode to the plurality of DM-RS symbols; and a unit for transmitting or receiving scheduling allocations for the device-to-device communication using the plurality of DM-RS sequences. In one configuration, the unit for determining group hopping enabled may be configured to operate based on one or more of the following: the device's travel speed, pre-configuration, or eNB signaling. In one configuration, to apply the group hopping mode to the plurality of DM-RS symbols, the unit for determining the plurality of DM-RS sequences may be configured to: change the root index of the Zadoff-Chu sequence for different DM-RS symbols.

[0128] In one configuration, device 1202 / 1202' may include a unit for determining a second plurality of DM-RS sequences associated with a data channel for device-to-device communication by applying a second set of hopping patterns to the second plurality of DM-RS symbols in the data channel of a subframe. In one configuration, to apply the second set of hopping patterns to the second plurality of DM-RS symbols, the unit for determining the second plurality of DM-RS symbols may be configured to change the root index of the Zadoff-Chu sequence for different DM-RS symbols.

[0129] In one configuration, device 1202 / 1202' may include a unit for transmitting or receiving data for device-to-device communication using the second plurality of DM-RS sequences.

[0130] The aforementioned units may be one or more of the aforementioned components of device 1202, and / or the processing system 1314 of device 1202' configured to perform the functions described in the aforementioned units. As described above, the processing system 1314 may include a TX processor 368, an RX processor 356, and a controller / processor 359. Therefore, in one configuration, the aforementioned units may be the TX processor 368, the RX processor 356, and the controller / processor 359 configured to perform the functions stated in the aforementioned units.

[0131] It should be understood that the specific order or hierarchy of blocks in the processing / flowcharts disclosed herein is merely one example of an exemplary method. It should be understood that these specific orders or hierarchies of blocks in the processing / flowcharts can be rearranged according to design preferences. Furthermore, some blocks can be combined or omitted. The appended method claims give the elements of various blocks in an exemplary order, but this does not imply that they are limited to the given specific order or hierarchy.

[0132] To enable any person skilled in the art to implement the various aspects described herein, the foregoing descriptions have been made regarding these aspects. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein may also be applied to other aspects. Therefore, the invention is not limited to the aspects shown herein, but is consistent with the full scope of the invention disclosure, wherein, unless specifically stated otherwise, the use of the singular to modify a component does not mean "one and only one," but can mean "one or more." The term "exemplary" as used herein means "serving as an example, illustration, or description." Any aspect described herein as "exemplary" should not be construed as preferred or advantageous over other aspects. Unless otherwise specifically stated otherwise, the term "some" refers to one or more. Combinations such as "at least one of A, B, or C," "one or more of A, B, or C," "at least one of A, B, and C," "one or more of A, B, and C," and "A, B, C, or any combination thereof," including any combination of A, B, and / or C, may include multiple A, multiple B, or multiple C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" can be only A, only B, only C, A and B, A and C, B and C, or A and B and C, wherein any such combination may contain one or more members of A, B, or C. All structural and functional equivalents of components throughout the various aspects described in this invention are expressly incorporated herein by reference and are intended to be covered by the claims; such structural and functional equivalents are well known or will be known to those skilled in the art. Furthermore, no disclosure herein is intended to be offered to the public, whether or not such disclosure is expressly stated in the claims. Terms such as "module," "apparatus," "element," "device," etc., are not substitutes for the term "unit." Therefore, the constituent elements of a claim should not be construed as functional modules unless the constituent element is expressly described using the term "functional module."

Claims

1. A method for wireless communication performed by a user equipment (UE), comprising: Determine the location of the UE; The maximum driving speed in the area is determined based on the speed limit of the area corresponding to the location of the UE; Based on the maximum driving speed, determine the driving speed of the UE; The transmission configuration of the UE for device-to-device communication is determined by the UE based on the UE's travel speed; as well as The device-to-device communication is sent based on the transmission configuration, wherein the transmission configuration includes the number of retransmissions.

2. The method according to claim 1, wherein, Sending the device-to-device communication includes sending an SA based on a scheduling allocation (SA) transmission configuration, wherein, in response to the UE determining to change the UE's SA transmission configuration based on the UE's travel speed, the SA is sent on a corresponding SA resource set other than the first SA resource set. Among them, SA resources are divided into multiple SA resource sets based on the type of SA transport configuration.

3. The method according to claim 1, wherein, The transmission configuration further includes at least one of the following: a modulation and coding scheme (MCS) or a number of resource blocks for transmission, and wherein, as the UE's travel speed increases, the transmission configuration is determined to include at least one of the following: Increase the number of resource blocks used for transmission; Reduce the modulation and coding scheme (MCS) value; or Increase the number of retransmissions.

4. The method according to claim 1, wherein, When the UE's travel speed decreases, the transmission configuration is determined to include at least one of the following: Reduce the number of resource blocks used for transmission; Increase the modulation and coding scheme (MCS) value; or Reduce the number of retransmissions.

5. The method according to claim 1, wherein, The maximum travel speed at the location of the UE is the speed limit of the area corresponding to the location of the UE.

6. The method according to claim 1, wherein, The travel speed of the UE is still determined based on the travel speed of the receiving UE.

7. The method according to claim 1, wherein, The transmission configuration is determined based on the association information between the driving speed and the corresponding transmission configuration, wherein the association information is pre-configured or received from the base station.

8. The method according to claim 2, wherein, The sending operation of the device-to-device communication includes: Data is sent via a data channel based on the data transmission configuration.

9. The method according to claim 8, wherein, The SA indicates the data transmission configuration and the location of resources used for the data channel.

10. The method according to claim 2, wherein, The sending operation of the device-to-device communication includes: In response to the UE determining to use a fixed SA transmission configuration, the SA is transmitted on any one of the plurality of SA resource sets.

11. The method according to claim 10, wherein, The first SA resource set is associated with the fixed SA transport configuration, and Each of the other SA resource sets is associated with a corresponding type of SA transport configuration and the fixed SA transport configuration.

12. The method according to claim 10, wherein, The size of each SA resource set and the at least one type of SA transmission configuration for each SA resource set are associated with the corresponding travel speed of the UE.

13. The method according to claim 12, wherein, The size of each SA resource set or at least one of the at least one type of SA transport configuration for each SA resource set is pre-configured or received from the base station.

14. A user equipment (UE) for wireless communication, comprising: A unit used to determine the location of the UE; A unit for determining the maximum travel speed of a region based on a speed limit of the region corresponding to the location of the UE; A unit for determining the travel speed of the UE based on the maximum travel speed; A unit for determining the transmission configuration of the UE for device-to-device communication based on the UE's travel speed; as well as A unit for transmitting device-to-device communication based on the transmission configuration, wherein the transmission configuration includes the number of retransmissions.

15. The UE according to claim 14, wherein, The unit for transmitting device-to-device communication is configured to transmit SA based on a scheduling allocation (SA) transmission configuration, wherein, in response to the UE determining to change the UE's SA transmission configuration based on the UE's travel speed, the SA is transmitted on a corresponding SA resource set other than the first SA resource set. Among them, SA resources are divided into multiple SA resource sets based on the type of SA transport configuration.

16. The UE according to claim 14, wherein, The transmission configuration further includes at least one of the following: a modulation and coding scheme (MCS) or a number of resource blocks for transmission, and wherein, as the UE's travel speed increases, the unit for determining the transmission configuration is configured to perform at least one of the following: Increase the number of resource blocks used for transmission; Reduce the modulation and coding scheme (MCS) value; or Increase the number of retransmissions.

17. The UE according to claim 14, wherein, When the UE's travel speed decreases, the unit for determining the transmission configuration is configured to perform at least one of the following: Reduce the number of resource blocks used for transmission; Increase the modulation and coding scheme (MCS) value; or Reduce the number of retransmissions.

18. The UE according to claim 14, wherein, The maximum travel speed corresponding to the location of the UE is the speed limit of the area corresponding to the location of the UE.

19. The UE according to claim 14, wherein, The driving speed is still determined based on the driving speed of the receiving UE.

20. The UE according to claim 14, wherein, The transmission configuration is determined based on the association information between the driving speed and the corresponding transmission configuration, wherein the association information is pre-configured or received from the base station.

21. The UE according to claim 15, wherein, The unit for transmitting device-to-device communication is configured as follows: Data is sent via a data channel based on the data transmission configuration.

22. The UE according to claim 21, wherein, The SA indicates the data transmission configuration and the location of resources used for the data channel.

23. The UE according to claim 15, wherein, The unit for transmitting device-to-device communication is configured as follows: In response to the UE determining to use a fixed SA transmission configuration, the SA is transmitted on any one of the multiple SA resource sets.

24. The UE according to claim 23, wherein, The first SA resource set is associated with the fixed SA transport configuration, and Each of the other SA resource sets is associated with a corresponding type of SA transport configuration and the fixed SA transport configuration.

25. The UE according to claim 23, wherein, The size of each SA resource set and the at least one type of SA transmission configuration for each SA resource set are associated with the corresponding travel speed of the UE.

26. The UE according to claim 25, wherein, The size of each SA resource set or at least one of the at least one type of SA transport configuration for each SA resource set is pre-configured or received from the base station.

27. A user equipment (UE) for wireless communication, comprising: Memory; as well as At least one processor, coupled to the memory, is configured to: Determine the location of the UE; The maximum driving speed in the area is determined based on the speed limit of the area corresponding to the location of the UE; Based on the maximum driving speed, determine the driving speed of the UE; The UE determines the transmission configuration of the UE for device-to-device communication based on the UE's travel speed; as well as The device-to-device communication is sent based on the transmission configuration, wherein the transmission configuration includes the number of retransmissions.

28. The UE according to claim 27, wherein, Sending the device-to-device communication includes sending the SA based on the scheduling allocation (SA) transmission configuration, wherein if the UE determines to change the SA transmission configuration based on the UE's travel speed, the SA is sent on a corresponding SA resource set outside the first SA resource set. Among them, SA resources are divided into multiple SA resource sets based on the type of SA transport configuration.

29. The UE according to claim 27, wherein, The transmission configuration further includes at least one of the following: a modulation and coding scheme (MCS) or a number of resource blocks for transmission, and wherein, when the UE's travel speed increases, the at least one processor configured to set the transmission configuration is configured to perform at least one of the following: Increase the number of resource blocks used for transmission; Reduce the modulation and coding scheme (MCS) value; or Increase the number of retransmissions.

30. The UE according to claim 27, wherein, When the UE's travel speed decreases, in order to determine the transmission configuration, the at least one processor is configured to perform at least one of the following: Reduce the number of resource blocks used for transmission; Increase the modulation and coding scheme (MCS) value; or Reduce the number of retransmissions.

31. The UE according to claim 27, wherein, The maximum travel speed corresponding to the location of the UE is the speed limit of the area corresponding to the location of the UE.

32. The UE according to claim 27, wherein, The driving speed is still determined based on the driving speed of the receiving UE.

33. The UE according to claim 27, wherein, The transmission configuration is determined based on the association information between the driving speed and the corresponding transmission configuration, wherein the association information is pre-configured or received from the base station.

34. The UE according to claim 28, wherein, The at least one processor configured to send device-to-device communication is configured to: Data is sent via a data channel based on the data transmission configuration.

35. The UE according to claim 34, wherein, The SA indicates the data transmission configuration and the location of resources used for the data channel.

36. The UE according to claim 28, wherein, The at least one processor configured to send device-to-device communication is configured to: If the UE determines to use a fixed SA transmission configuration, then the SA is transmitted on any of the multiple SA resource sets.

37. The UE according to claim 36, wherein, The first SA resource set is associated with the fixed SA transport configuration, and Each of the other SA resource sets is associated with a corresponding type of SA transport configuration and the fixed SA transport configuration.

38. The UE according to claim 36, wherein, The size of each SA resource set and the at least one type of SA transmission configuration for each SA resource set are associated with the corresponding travel speed of the UE.

39. The UE according to claim 38, wherein, The size of each SA resource set or at least one of the at least one type of SA transport configuration for each SA resource set is pre-configured or received from the base station.

40. A computer-readable medium for a user equipment (UE) storing computer-executable code, including code for performing the following operations: Determine the location of the UE; The maximum driving speed in the area is determined based on the speed limit of the area corresponding to the location of the UE; Based on the maximum driving speed, determine the driving speed of the UE; The UE determines the transmission configuration of the UE for device-to-device communication based on the UE's travel speed; as well as The device-to-device communication is sent based on the transmission configuration, wherein the transmission configuration includes the number of retransmissions.

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