Sidelink positioning systems and methods for device-to-device communication

Abstract

The present disclosure relates to systems, apparatus, methods, and non-transitory computer readable media for receiving, by a first wireless communication device, a sidelink positioning reference signal (SL PRS) resource configuration from a higher layer for communication of the SL PRS in a time domain unit, and transmitting, by the first wireless communication device, the SL PRS to a second wireless communication device according to the SL PRS resource configuration.

Description

Technical Field

[0001] The present disclosure generally relates to wireless communication, and more particularly to device-to-device communication. Background Art

[0002] Sidelink (SL) communication refers to wireless radio communication between two or more user equipments (UEs). In this type of communication, two or more UEs that are geographically close to each other can communicate without routing through a network (e.g., a base station (BS)) or a core network. Thus, data transmission in SL communication is different from typical cellular network communication, which includes transmitting data to and receiving data from a BS. In SL communication, data is directly transmitted from a source UE to a target UE through, for example, a unified air interface (such as the PC5 interface) without passing through a BS. Summary of the Invention

[0003] The example arrangements disclosed herein are intended to address issues related to one or more of the problems existing in the prior art and provide additional features that will become apparent from the following detailed description in conjunction with the accompanying drawings. According to various arrangements, example systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these arrangements are provided by way of example and are not restrictive, and it will be apparent to those of ordinary skill in the art who have read the present disclosure that various modifications can be made to the disclosed arrangements while remaining within the scope of the present disclosure.

[0004] Some arrangements of the present disclosure relate to systems, methods, apparatuses, and non-transitory computer-readable media, and involve: receiving, by a first wireless communication device, a sidelink positioning reference signal (SL PRS) resource configuration from a higher layer for communicating SL PRS in a time domain unit, and sending, by the first wireless communication device, an SL PRS to a second wireless communication device according to the SL PRS resource configuration.

[0005] The above aspects and other aspects and their embodiments are described in more detail in the drawings, the specification, and the claims. Brief Description of the Drawings

[0006] The following describes various example arrangements of the present solution in detail with reference to the following diagrams or drawings. These drawings are provided for illustrative purposes only, and these drawings merely depict example arrangements of the present solution so that readers can understand the present solution. Therefore, these drawings should not be regarded as limiting the breadth, scope, or applicability of the present solution. It should be noted that for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

[0007] Figure 1A is a diagram showing an example wireless communication system according to various arrangements.

[0008] Figure 1B is a diagram showing a block diagram of an example wireless communication system for transmitting and receiving downlink communication signals, uplink communication signals, and / or SL communication signals according to various arrangements.

[0009] Figure 2 shows an example scenario of SL communication according to various arrangements.

[0010] Figure 3 is a flowchart showing an example method of communication for performing SL positioning-related transmissions according to various arrangements.

[0011] Figure 4 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SLPRS for multiple UEs in a structure of a single time slot according to various arrangements.

[0012] Figure 5 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SLPRS for multiple UEs in a structure of a single time slot and a structure of a single time slot according to various arrangements.

[0013] Figure 6 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure according to various arrangements.

[0014] Figure 7 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure according to various arrangements.

[0015] Figure 8 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure according to various arrangements.

[0016] Figure 9 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure according to various arrangements.

[0017] Figure 10 is a signaling diagram showing example synchronization methods for UE-based positioning according to various arrangements.

[0018] Figure 11 is a signaling diagram showing example synchronization methods for UE-based positioning according to various arrangements.

[0019] Figure 12 is a flowchart showing an example method for configuring and communicating SL PRS and SCI according to various arrangements. Detailed implementation manners

[0020] Various example arrangements of the present solution are described below with reference to the accompanying drawings so that those of ordinary skill in the art can make and use the present solution. As will be apparent to those of ordinary skill in the art after reading this disclosure, various changes or modifications can be made to the examples described herein without departing from the scope of the present solution. Therefore, the present solution is not limited to the example arrangements and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein is merely an example method. Based on design preferences, the specific order or hierarchy of steps in the disclosed method or process can be rearranged while remaining within the scope of the present solution. Therefore, those of ordinary skill in the art will understand that the methods and techniques disclosed herein provide various steps or actions in an example order, and the present solution is not limited to the specific order or hierarchy provided unless otherwise expressly stated.

[0021] With the rise of wireless multimedia services, users' demands for high data rates and user experience continue to grow, which poses higher requirements on the system capacity and coverage of traditional cellular networks. In addition, public safety, social networks, proximity data sharing, and local announcements have gradually expanded the demand for proximity services, which enable users to understand nearby users or objects and communicate with nearby users or objects. The high data rate capabilities and support for proximity services of traditional network-centric cellular networks are limited. Against this background, device-to-device (D2D) communication has emerged to address the deficiencies of the network-centric model. The application of D2D technology can relieve the burden on cellular networks, reduce the battery power consumption of UEs, increase data rates, and enhance the robustness of network infrastructure, thus meeting the above-mentioned demands for high data rate services and proximity services. D2D technology is also known as Proximity Services (ProSe), sidelink / SL communication, and so on.

[0022] In some arrangements, wireless communication can be performed on carriers, frequency bands, and / or spectrums. Some carriers are licensed carriers because these carriers are licensed by a government or other authority for exclusive use by a service provider. Some carriers are unlicensed carriers, which are not licensed by any government or authority for exclusive use. Two or more service providers can operate on an unlicensed carrier. Currently, UEs can communicate directly with each other on a licensed carrier (e.g., without using a base station for communication). A solution for UEs to communicate with each other on an unlicensed carrier has not been provided.

[0023] In some arrangements, a licensed carrier refers to a carrier, frequency band, or spectrum licensed by a government or authority (such as the Federal Communications Commission (FCC) in the United States and the European Telecommunications Standards Institute (ETSI) in Europe) for exclusive use by a service provider. An unlicensed carrier (or shared spectrum) refers to a carrier, frequency band, or spectrum that is not licensed by a government or other authority. Two or more service providers can operate on an unlicensed carrier.

[0024] Solutions for supporting SL positioning in a New Radio (NR) system include: SL positioning reference signal (e.g., SL positioning reference signal (SLPRS)) measurements and reports for SL positioning considering various positioning methods (such as Round Trip Time (RTT), Time Difference Of Arrival (TDOA), angle-based positioning methods, etc.), and resource allocation for SL PRS considering both dedicated resource pools and shared resource pools for SL PRS and considering both resource allocation scheme 1 and resource allocation scheme 2.

[0025] Different from the resource allocation of the Physical SL Control Channel (PSCCH) and Physical SL Shared Channel (PSSCH) in SL communication, where the time granularity is a time slot and the frequency granularity is a subchannel, the SL PRS resource and / or SL PRS resource set can be defined and used as the resource allocation granularity. Accordingly, mechanisms can be defined as follows: SL PRS sequence configuration, congestion control for SL positioning, and Inter-UE Coordination (IUC).

[0026] Refer to Figure 1A, shows an example wireless communication system 100. The wireless communication system 100 shows group communication in a cellular network. In a wireless communication system, network-side communication nodes or networks can include next-generation Node B (gNB), E-UTRAN (Evolved Universal Terrestrial Radio Access Network) node B (also referred to as evolved Node B, eNodeB or eNB), pico station, femto station, Transmission / Reception Point (TRP), or Access Point (AP), etc. Terminal-side nodes or UEs can include devices such as, for example, mobile devices, smart phones, cellular phones, Personal Digital Assistant (PDA), tablets, laptop computers, wearable devices, or vehicles with in-vehicle communication systems, etc. In some examples, the UE can be an in-vehicle UE, a pedestrian UE, a Road-Side UE (RSU), and a Positioning Reference Unit (PRU), etc. The UEs described herein are capable of implementing the methods described herein in the case of known or unknown positions. In Figure 1A , the network-side and terminal-side communication nodes are represented by network (BS) 102 and UEs 104a and 104b, respectively. In some arrangements, network 102 and UEs 104a / 104b are sometimes referred to as "wireless communication nodes" and "wireless communication devices", respectively. These communication nodes / communication devices can perform wireless communication.

[0027] In Figure 1AIn the illustrated arrangement, network 102 may define a cell 101, where UEs 104a and 104b are located within the cell 101. UEs 104a and / or 104b may move or remain stationary within the coverage of cell 101. The first UE 04a may communicate with network 102 via communication channel 103a. Similarly, the first UE 04b may communicate with network 102 via communication channel 103b (also referred to as communication channel link 103b). Additionally, UEs 104a and 104b may communicate with each other via communication channel 105. The communication channels 103a between the respective UEs and the network and communication channel 104b may be implemented using an interface (such as the Uu interface), which is also referred to as the Universal Mobile Telecommunication System (UMTS) air interface. The communication channel 105 between the UEs is an SL communication channel and may be implemented using the PC5 interface, which is introduced to address high mobility speed and high density applications, such as D2D communication, Vehicle-to-Vehicle (V2V) communication, Vehicle-to-Pedestrian (V2P) communication, Vehicle-to-Infrastructure (V2I) communication, or Vehicle-to-Network (V2N) communication, etc. In some instances, vehicle network communication modes are collectively referred to as Vehicle-to-Everything (V2X) communication. Network 102 is connected to the Core Network (CN) 108 via an external interface 107 (such as the Iu interface).

[0028] In some examples, a remote UE (such as the first UE 04b) that does not communicate directly with network 102 or CN 108 (e.g., communication channel link 103b is not established) communicates indirectly with network 102 and CN 108 using the SL communication channel 105 via a relay UE (such as the first UE 04a), which may communicate directly with network 102 and CN 108, or communicate indirectly with network 102 and CN 108 via another relay UE that can communicate directly with network 102 and CN 108.

[0029] Figure 1B A block diagram of an example wireless communication system for transmitting and receiving downlink communication signals, uplink communication signals, and SL communication signals according to some arrangements of the present disclosure is shown. In some arrangements, the system may transmit and receive data in a wireless communication environment (such as Figure 1A the wireless communication system 100 as described above).

[0030] The system generally includes a network 102 and UEs 104a and 104b, as Figure 1A shown. The network 102 includes a network transceiver module 110 (also referred to as a BS transceiver module 110), a network antenna 112, a network memory module 116 (also referred to as a BS memory module 116), a network processor module 114 (also referred to as a BS processor module), and a network communication module 118, with each module coupled or interconnected to one another via a data communication bus 120 as needed. The first UE 104a includes a UE transceiver module 130a, a UE antenna 132a, a UE memory module 134a, and a UE processor module 136a, with each module coupled or interconnected to one another via a data communication bus 140a as needed. Similarly, the first UE 104b includes a UE transceiver module 130b, a UE antenna 132b, a UE memory module 134b, and a UE processor module 136b, with each module coupled or interconnected to one another via a data communication bus 140b as needed. The network 102 communicates with the UEs 104a and 104b via one or more communication channels 150, which may be any suitable wireless channels or other media known in the art for transmitting data as described herein.

[0031] The system may also include any number of modules in addition to Figure 1B the modules shown. Those skilled in the art will understand that the various exemplary blocks, modules, circuits, and processing logics described in connection with the arrangements disclosed herein may be implemented in hardware, computer-readable software, firmware, or any practical combination thereof. To clearly illustrate this interchangeability and compatibility between hardware, firmware, and software, the various illustrative components, blocks, modules, circuits, and steps are generally described in terms of their functionality. Whether these functions are implemented as hardware, firmware, or software depends on the particular application and the design constraints imposed on the overall system. Persons familiar with the concepts described herein may implement these functions in a suitable manner for each particular application, but these implementation decisions should not be construed as limiting the scope of the present disclosure.

[0032] Wireless transmission from the antenna of one of UE 104a and UE 104b to the antenna of network 102 is referred to as an uplink transmission, while wireless transmission from the antenna of network 102 to the antenna of one of UE 104a and UE 104b is referred to as a downlink transmission. According to some arrangements, each of UE transceiver modules 130a and 130b may be referred to herein as an uplink transceiver or a UE transceiver. The uplink transceiver may include a transmitter circuit and a receiver circuit respectively coupled to corresponding antennas 132a and 132b. A duplex switch may alternately couple the uplink transmitter or receiver to the uplink antenna in a time-division duplex manner. Similarly, network transceiver module 110 may be referred to herein as a downlink transceiver or a network transceiver. The downlink transceiver may include an RF (Radio Frequency) transmitter circuit and an RF receiver circuit respectively coupled to antenna 112. A downlink duplex switch may alternately connect the downlink transmitter or receiver to antenna 112 in a time-division duplex manner. The operations of transceiver 110 and transceivers 130a and 130b are coordinated in time such that while the downlink transmitter is coupled to antenna 112, the uplink receivers are coupled to antennas 132a and 132b to receive transmissions through wireless communication channel 150. In some arrangements, UE 104a and UE 104b may use UE transceivers 130a and 130b through respective antennas 132a and 132b to communicate with network 102 through wireless communication channel 150. Wireless communication channel 150 may be any wireless channel or other medium known in the art suitable for downlink and / or uplink transmission of the data described herein. UE 104a and UE 104b may communicate with each other through wireless communication channel 170. Wireless communication channel 170 may be any wireless channel or other medium suitable for SL transmission of the data described herein.

[0033] Each of UE transceivers 130a and 130b and network transceiver 110 is configured to communicate through wireless data communication channel 150 and cooperate with a suitably configured antenna arrangement that is capable of supporting a particular wireless communication protocol and modulation scheme. In some arrangements, UE transceivers 130a and 130b and network transceiver 110 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G and 6G standards, etc. However, it should be understood that the present disclosure is not necessarily limited to applications to specific standards and associated protocols. Rather, UE transceivers 130a and 130b and network transceiver 110 may be configured to support alternative or additional wireless data communication protocols, including future standards or their variants.

[0034] Processor modules 136a and 136b and processor module 114 may be implemented respectively by a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. Thus, the processor may be implemented as a microprocessor, a controller, a microcontroller, or a state machine, etc. The processor may also be implemented as a combination of computing devices, e.g., a combination of a digital signal processor and a microprocessor, a combination of multiple microprocessors, a combination of one or more microprocessors with a digital signal processor core, or any other such configured combination.

[0035] Furthermore, the methods and algorithms described in connection with the arrangements disclosed herein can be embodied directly in hardware, firmware, software modules executed respectively by processor modules 114, 136a, and 136b, or any practical combination thereof. Memory modules 116, 134a, and 134b can be implemented as RAM (Random Access Memory), flash memory, ROM (Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), registers, hard disks, removable disks, CD-ROM (Compact Disc Read Only Memory), or any other form of storage medium known in the art. In this regard, memory modules 116, 134a, and 134b can be coupled respectively to processor modules 114, 136a, and 136b such that processor modules 114, 136a, and 136b can read information from and write information to memory modules 116, 134a, and 134b. Memory modules 116, 134a, and 134b can also be integrated into their respective processor modules 114, 136a, and 136b. In some arrangements, memory modules 116, 134a, and 134b can each include cache memory for storing temporary variables or other intermediate information during the execution of instructions executed by processor modules 116, 134a, and 134b, respectively. Memory modules 116, 134a, and 134b can also each include non-volatile memory for storing instructions executed by processor modules 114, 136a, and 136b, respectively.

[0036] The network interface (also referred to as the network communication module) 118 generally represents the hardware, software, firmware, processing logic, and / or other components of network 102 that implement two-way communication between network transceiver 110 and other network components and communication nodes configured to communicate with network 102. For example, network interface 118 may be configured to support Internet or WiMAX (World Interoperability for Microwave Access) services. In a typical deployment, without limitation, network interface 118 provides an 802.3 Ethernet interface that enables network transceiver 110 to communicate with a traditional Ethernet-based computer network. In this way, network interface 118 may include a physical interface for connection to a computer network (e.g., a Mobile Switching Center (MSC)). As used herein, the term "configured for" or "configured to" with respect to a specified operation or function refers to a device, component, circuit, structure, machine, signal, etc. that is physically constructed, programmed, formatted, and / or arranged to perform the specified operation or function. Network interface 118 may enable network 102 to communicate with other networks or a core network via a wired connection or a wireless connection.

[0037] In some arrangements, each of UE 104a and UE 104b may operate in a hybrid communication network in which the UEs communicate with network 102 and with other UEs, e.g., communicate between 104a and 104b. As described in further detail below, UE 104a and UE 104b support SL communication with other UEs, and downlink / uplink communication between network 102 and UE 104a and UE 104b. Generally, SL communication enables UE 104a and UE 104b to establish a direct communication link with each other, or with other UEs in different cells, without network 102 relaying data between the UEs.

[0038] Figure 2 is a diagram showing an example system 200 for SL communication according to various arrangements. As Figure 2 shown, a network (also referred to as a base station) 210 (such as, Figure 1A network 102 in) broadcasts a signal that is received by a first UE 230, a second UE 230, and a third UE 240. Figure 2UE 220 and UE 230 therein are shown as vehicles with in-vehicle communication networks, while UE 240 is shown as a mobile device. As shown, via SL, UE 220 to UE 240 can communicate with each other over the air interface (e.g., direct transmission and direct reception) without the forwarding of base station 210 or core network 250. This type of V2X communication is referred to as PC5-based V2X communication or V2X SL communication.

[0039] As used herein, when two UEs 104a or 104b communicate with each other via SL over communication channel 105 / 170, the UE that sends data to the other UE is referred to as the transmitting (TX or Tx) UE, while the UE that receives the data is referred to as the receiving (RX or Rx) UE.

[0040] For PSCCH / PSSCH resource allocation in SL communication, the time granularity (e.g., time slot and subchannel) is defined as the PSSCH frequency domain resource unit. For each resource pool, the size of the subchannel is configured. In addition, the SL Channel Busy Ratio (CBR) and SL Channel Occupancy Ratio (CR) for SL congestion control are both defined based on the subchannel busy ratio or subchannel occupancy ratio. For SL positioning, the SL PRS allocation granularity can apply time slot-based and subchannel-based SL PRS resource allocation, sub-time slot-based SL PRS resource allocation, or SL PRS resource-based allocation.

[0041] Regarding SL PRS resource allocation, both Scheme 1 (e.g., network-centric operation of SL PRS resource allocation) and Scheme 2 (e.g., UE autonomous SL PRS resource allocation) support SL positioning / ranging.

[0042] Figure 3 is a flowchart showing an example method 300 for configuring and communicating for SL PRS according to various arrangements. The method 300 can be executed using system 100 and system 200. At 310, UE 104a receives an SL PRS resource configuration from a higher layer for communicating SL PRS in a time domain unit. At 330, UE 104a sends an SL PRS to another UE (such as a second UE (e.g., UE 104b or a second wireless communication device)) according to the SL PRS resource configuration.

[0043] In some arrangements, the starting symbol can be aligned among multiple resource pools. In a dedicated resource pool, time-division multiplexing (TDM)-based multiplexing of SL PRSs from different UEs can be supported in one time slot. To further increase the multiplexing capacity of UEs in a time slot, both TDM-based multiplexing and comb-based multiplexing of SL PRSs from UEs can be preconfigured or configured in a single time slot.

[0044] Figure 4 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRSs for multiple UEs in a structure 400 of a single time slot according to various arrangements. The horizontal dimension or x-dimension represents time-domain resources, and the vertical dimension or y-dimension represents frequency-domain resources. As Figure 4 shown, SL PRS resource 401 and SL PRS resource 402 are comb-based multiplexed in the same symbol. SL PRS resource 403 and SL PRS resource 404 are comb-based multiplexed in the same symbol. SL PRS resource 401 and SL PRS resource 402 are time-division multiplexed (TDM-ed) with SL PRS resource 403 and SL PRS resource 404. Different UEs can use SL PRS resource 401, SL PRS resource 402, SL PRS resource 403, and SL PRS resource 404 to transmit SL PRSs. As shown, the structure 400 of the time slot includes sidelink control information (SCI) 411, SCI 412, SCI 413, and SCI 414, which respectively correspond to (e.g., schedule) SL PRS resource 401, SL PRS resource 402, SL PRS resource 403, and SL PRS resource 404. SCI 411, SCI 412, SCI 413, and SCI 414 are located in the time domain between automatic gain control (AGC) block 420a and AGC block 420b. SL PRS resource 401 and SL PRS resource 402 are located in the time domain between AGC symbol 420b and AGC symbol 420c. SL PRS resource 403 and SL PRS resource 404 are located in the time domain between AGC symbol 420c and interval 430.

[0045] In addition, to avoid AGC issues, the time-domain resources for SLPRS are aligned among multiple resource pools. The time-domain resources for SL PRS include at least one of the following and are defined by at least one of the following: the time-domain starting point (e.g., starting symbol) of the SL PRS and the time-domain length (e.g., the number of symbols of the SL PRS in a time slot), the position of the SL PRS resource in the time slot. The multiple resource pools can be at least one or more of the following: dedicated resource pools for SL positioning, shared resource pools. The multiple resource pools can be frequency division multiplexed (FDMed) in one SL frequency-domain resource (e.g., Bandwidth Part (BWP)).

[0046] In some arrangements, the time-domain configuration of the SL PRS resources of the first UE (e.g., UE 104a) is aligned with the time-domain configuration of the SL PRS resources of multiple UEs. The SL PRS resources of the first UE and the SL PRS resources of multiple UEs are time division multiplexed (TDMed), comb-based multiplexed, or both TDM and comb-based multiplexed within a time-domain unit. The SL PRS resources are configured within a resource pool, which is a dedicated resource pool or a shared resource pool. In some examples, the time-domain unit is a time slot. The SL PRS resource configuration is received from a higher layer by signaling, and the signaling includes at least one of the following: Long Term Evolution Positioning Protocol (LPP) from a Location Management Function (LMF), Sidelink Positioning Protocol (SLPP) from the LMF or the UE, Radio Access Control (RRC) or Medium Access Control (MAC) from BS102, the higher layer of the first UE (the higher layer includes at least one of the following: MAC layer, RRC layer, or Non-Access Stratum (NAS) layer); or the SL PRS resource configuration is pre-configured.

[0047] In some arrangements, the SL PRS resource configuration includes a time-domain configuration. The time-domain configuration includes at least one of the following: the time-domain starting point in the time-domain unit, the time-domain length, or the SL PRS resource position.

[0048] Figure 5FIG. is a diagram illustrating an example allocation of time domain resources and frequency domain resources for transmitting SL PRS for multiple UEs in a structure 400 of a single time slot and a structure 500 of a single time slot according to various arrangements. The horizontal dimension or x dimension represents time domain resources, and the vertical dimension or y dimension represents frequency domain resources. Figure 4 The time slot structure 400 described in includes SL PRS resources 401, 402, 403, and 404 in a first resource pool.

[0049] For the time slot structure 500, SL PRS resource 501 is TDM'ed with SL PRS resource 502. SL PRS resource 501 and SL PRS resource 502 use the same frequency domain resources. Different UEs can use SL PRS resource 501 and SL PRS resource 502 to transmit SL PRS. As shown, the structure 500 of the time slot includes SCI 511 and SCI 512, which respectively correspond to (e.g., schedule) SL PRS resource 501 and SL PRS resource 502. SCI 511 and SCI 512 are located in the time domain between AGC symbol 520a and AGC symbol 520b. SL PRS resource 501 is located in the time domain between AGC symbol 520b and AGC symbol 520c. SL PRS resource 502 is located in the time domain between AGC symbol 520c and interval 530. SL PRS resource 501 and SL PRS resource 502 are in a second resource pool.

[0050] The SL PRS resources 401, 402, 403, and 404 in the first resource pool and the SL PRS resources 501 and 502 in the second resource pool can be FDMed. In some examples, the SL PRS resources 401, 402, 403, and 404 preconfigured or configured in the first resource pool and the SL PRS resources 501 and 502 preconfigured or configured in the second resource pool can be transmitted in the same time-domain resource (e.g., the same time slot as shown in the figure). Although the SL PRS resources 401, 402, 403, 404, 501, and 502 are different in different resource pools, their corresponding AGC symbols 420a, 420b, 420c, 520a, 520b, and 520c are aligned, or the starting symbols of the SL PRS resources 401, 402, 403, 404, 501, and 502 are aligned.

[0051] In some examples, the time-domain resources for SL PRS communication can be aligned among multiple resource pools. In some arrangements, the network preconfigures or configures the position of the AGC symbol in the time slot, which is preconfigured or configured at the BWP level, carrier level, or cross-carrier for carrier aggregation (CA). In some examples, the AGC time-domain resource (e.g., AGC symbol) is defined as one of the following: the AGC time-domain resource before the SL PRS resource, the AGC time-domain resource before the PSCCH resource, or the starting symbol for SL positioning in the time slot. In some examples, the network preconfigures or configures the position of each AGC symbol in the time slot for each SLBWP. In some arrangements, in method 300, UE 104a receives the position of the AGC resource in the time-domain unit for each resource pool in at least one resource pool or multiple resource pools, for each frequency-domain resource in at least one frequency-domain resource (e.g., BWP), for each carrier in at least one carrier, or for multiple carriers for CA. In some arrangements, the AGC resource is defined by at least one of the following AGC time-domain resources: the AGC time-domain resource before one of the SL PRS resources in each SL PRS resource, the AGC time-domain resource before the resource for PSCCH communication, or the starting time for SL positioning in the time-domain resource.

[0052] In some arrangements, the network configures the time-domain resources of SL PRS in a time slot for each SL BWP at the BWP level, carrier level, or across carriers used for CA. In some examples, the network preconfigures or configures the position of each time-domain resource of SL PRS in a time slot. In some arrangements, the SL PRS resource configuration includes the configuration of time-domain SL PRS resources in time-domain units for each resource pool of at least one resource pool or multiple resource pools, for each frequency-domain resource of at least one frequency-domain resource, for each carrier of at least one carrier, or for multiple carriers used for CA.

[0053] In some arrangements, the network preconfigures or configures the time-domain resources of SL PRS in a time slot in each resource pool. The resource pool can be a dedicated resource pool for SL PRS or a shared resource pool. In some examples, the time-domain resources of SL PRS are aligned among multiple resource pools.

[0054] In some arrangements, the time resources of SL PRS in a resource pool can be aligned among multiple UEs, and the resource pool can be at least one or more of a dedicated resource pool and a shared resource pool. The alignment of two time-domain resources means that the start positions of the two time-domain resources are the same and / or the end positions of the two time-domain resources are the same. Considering that the resource pool for SL positioning and the resource pool for SL communication can be (pre)configured in an SL BWP, but TDM-based multiplexing between SL data of different UEs in a time slot is not supported. It is difficult to ensure that the AGC symbol positions in a time slot are the same for the SL communication resource pool and the SL PRS resource pool.

[0055] In some arrangements, the time resources of SL PRS can be aligned across UEs at multiple resource pool levels. In other words, for all resource pools used for SL positioning, the start symbol or AGC symbol position of SL PRS resources within a time slot can be aligned.

[0056] In some arrangements, for SL PRS transmission, SL PRS transmission using periodic reservation and SL PRS transmission without using periodic reservation (e.g., using aperiodic reservation) are supported. For SL PRS transmission using periodic reservation, the SCI can include a resource reservation period field to indicate the periodicity of the same SL-PRS resources.

[0057] Regarding SL PRS transmission using aperiodic reservation, the SL PRS resource reservation in the same time slot is regarded as PSCCH. In some examples, up to N aperiodic resource reservations can be configured in other time slots. The number N can be preconfigured or configured by the network in the resource pool, for example, N = 2 or 1. Figure 6FIG. is a diagram illustrating an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure 600 according to various arrangements. The horizontal dimension or x-dimension represents time-domain resources, and the vertical dimension or y-dimension represents frequency-domain resources. In some arrangements, in an aperiodic reservation scheme, within one SL PRS reservation period 602, SCI 611 schedules SL PRS resources with 3 aperiodic reservations (denoted as SL PRS resource 620a, SL PRS resource 620b, and SL PRS resource 620c).

[0058] In some arrangements, there is a one-to-one mapping relationship between PSCCH resources (resources for SCI transmission) and SLPRS resources in time-domain resources (e.g., time slots). Such a configuration may include the following configurations: time resources (e.g., the number of time slots), frequency resources (e.g., the number of physical resource blocks (PRBs)), demodulation reference signal (DMRS) scrambling ID, and the number of reservation bits. In some examples, for future aperiodic reservations, all aperiodic SL PRS reservations indicated in one SCI have the same SL PRS resource ID, and there is no need to additionally include SL PRS resource ID (one or more ID) information in the SCI. In other words, multiple aperiodic reserved SL PRS are SL PRS resource repetitions. In addition, the information included in the SCI includes a list of at least one of the following: source ID of the aperiodic reserved SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation. For example, in Figure 6 all SL PRS resources 620a, 620b, and 620c have the same SL PRS resource ID (e.g., 1), and SCI 611 does not include any SL PRS resource ID.

[0059] In some examples, for future aperiodic reservation, the number of SL PRS resource IDs indicated in the SCI is 1 less than the number of reserved SL PRS resources indicated in the SCI. In some arrangements, the information included in the SCI includes a list of at least one of the following: source ID of the aperiodic reservation SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation. In some arrangements, the information included in the SCI includes multiple lists, the number of lists being equal to the number of SL PRS reservations for transmissions not using periodic reservation, or the number of lists being 1 more than the number of (one or more) SL PRS resource IDs indicated in the SCI. Each list includes at least one of the following: source ID of the aperiodic reservation SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation. For example, the SCI includes at most 2 more SL PRS resource indications (e.g., 2 SL PRS resource IDs) for future reservations. For example, in Figure 6 SL PRS resource 620a, SL PRS resource 620b, and SL PRS resource 620c each have different SL PRS resource IDs, e.g., 1, 2, and 3.

[0060] In some arrangements, there is a one-to-many mapping relationship between the PSCCH resources (resources for SCI transmission) and one or more SL PRS resources in a time slot. In some examples, for future aperiodic reservation, the SCI indicates one SLPRS resource to indicate which SL PRS resource is reserved for all aperiodic reservations. Such a configuration may include the following configurations: time resources (e.g., the number of time slots), frequency resources (e.g., the number of PRBs), DMRS scrambling ID, and the number of reserved bits. Since there is no one-to-one mapping relationship, the SCI should still indicate which resource in the same time slot is reserved. In addition, the information included in the SCI includes a list of at least one of the following: source ID of the aperiodic reservation SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation.

[0061] In some examples, given a one-to-one or one-to-many mapping between a PSCCH resource and one or more SL PRS resources, the one or more SL PRS resources mapped to the same PSCCH resource can be regarded as an SL PRS resource bundle. The PSCCH can only reserve the (one or more) SL PRS resources belonging to the corresponding SL PRS resource bundle according to the mapping relationship. For example, assume that the PSCCH / SCI resource 1 is mapped to the SL PRS resource bundle {SL PRS resource 1, SL PRS resource 2, SL PRS resource 3}. Whether it is periodic resource reservation or aperiodic resource reservation, the PSCCH / SCI 1 can only reserve one or more SL PRS resources from the SL PRS resource bundle {SL PRS resource 1, SL PRS resource 2, SL PRS resource 3}. In other words, whether in a periodic manner or an aperiodic manner, the PSCCH / SCI 1 cannot reserve the SL PRS resource 4.

[0062] In some examples, for future aperiodic reservations, the SCI can indicate multiple SL PRS resources, and each SL PRS resource among the multiple SL PRS resources can be associated with a resource ID. The number of SL PRS resource IDs indicated in the SCI is equal to the number of reserved SL PRS resources indicated by the SCI. For example, if the SCI indicates 3 aperiodic SL PRS resources, then 3 SL PRS resource IDs should be included in the SCI. In some arrangements, the information included in the SCI includes a list of at least one of the following: source ID of the aperiodic reserved SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation. In some arrangements, the information included in the SCI includes multiple lists, and the number of lists is equal to the number of SL PRS reservations for transmissions not using periodic reservations, or equal to the number of (one or more) SL PRS resource IDs indicated in the SCI, where each list includes at least one of the following: source ID of the aperiodic reserved SL PRS, destination ID, resource reservation period, broadcast type, time resource allocation.

[0063] In some examples, in the sensing-based resource selection for SL positioning, an entity (such as the Medium Access Control (MAC) layer or the physical layer) is responsible for the sensing trigger.

[0064] In some arrangements, the physical layer may control the sensing process, including triggering resource preemption and re-evaluation. In some examples, the physical layer of the UE may perform tasks of the MAC layer, including determining the timing to start sensing and determining at least one of the following: resource pool, priority of SL PRS transmission, remaining packet delay budget, SL PRS resource ID, number of symbols for SL PRS, multiple SL PRS resources (e.g., SL PRS resource IDs), one or more PSCCH resources, SL PRS resource packets including one or more SL PRS resources associated with the PSCCH resources, resource reservation interval, and subset of resources for preemption or re-evaluation, etc.

[0065] In some arrangements, the higher layer (e.g., MAC layer) triggers the sensing process. For example, the MAC layer of the Tx UE may request the Tx UE to determine a subset of resources. The MAC layer may select resources for PSSCH / PSCCH transmission from the subset of resources based on the candidate resource report of the physical layer. In some examples, the MAC layer triggers the sensing process and provides at least one or more of the following: SL PRS resource ID, number of symbols for SL PRS, multiple SL PRS resources (e.g., SL PRS resource IDs), one or more PSCCH resources, SL PRS resource packets including one or more SL PRS resources associated with the PSCCH resources, resource pool, priority of SL PRS transmission, remaining packet delay budget, number of sub-channels, resource reservation interval, subset of resources for preemption or re-evaluation, and indication of resource selection mechanism, etc.

[0066] In some arrangements, the higher layer (e.g., MAC layer) requests the UE to determine a subset of resources, and the higher layer selects resources for SL PRS transmission and / or PSCCH / SCI transmission from the subset of resources. As part of the re-evaluation or preemption process, the higher layer provides a set of resources that may need to be re-evaluated and a set of resources that may need to be preempted. In some arrangements, to select resources for SL PRS transmission and / or PSCCH / SCI transmission, the UE (e.g., the physical layer of the UE) determines a set of resources that may need to be re-evaluated and a set of resources that may need to be preempted.

[0067] In some arrangements, based on a sensing result (e.g., an initial sensing), the UE may determine a set S of candidate resources for SL PRS transmission. These candidate resources may be associated with the same PSCCH resource. In response to determining that a resource in the set for re-evaluation is not a member of set S, the UE assumes that the resource has been removed or discarded. In response to determining that a resource in the set for pre-emption is not a member of set S and the resource meets the condition for exclusion during the sensing process and the priority of the resource is lower than the received SL PRS priority, the UE assumes that the resource has been removed or discarded. For pre-emption, determining that the priority of the resource is lower than the received SL PRS priority is associated with a higher layer parameter (e.g., sl-prs-PreemptionEnable). The higher layer parameter for pre-emption may be configured or pre-configured in each resource pool, and the resource pool may be a dedicated resource pool or a shared resource pool. The higher layer parameter may be configured in RRC, LPP, or SLPP. Candidate values for the higher layer parameter for pre-emption may include at least one of the following: enable, disable, or one or more priority values. The priority value may be an integer or a non-integer.

[0068] In some arrangements, for those resources that are evaluated for re-evaluation or pre-emption (e.g., the UE determines that these resources have been reserved by other UEs and / or the priority of these (one or more) resources is lower than the priority of the resources of other UEs, or in other words, these (one or more) resources are determined to be removed or discarded), based on another sensing process, the UE replaces the removed or discarded (one or more) resources with the (one or more) resources sensed as candidates and selected by the MAC layer or the physical layer. The removed / discarded resources and the (one or more) resources used to replace the removed / discarded resources have at least the same SL PRS resource ID, the same associated PSCCH resource, the same PSCCH resource, the same SL PRS resource packet, the same broadcast type indicator, the same source ID, the same destination ID, and the same SL PRS priority. The removed / discarded resources and the (one or more) resources used to replace the removed / discarded resources are in different time domain units. The time domain unit may be a time slot.

[0069] In some examples, in the SL positioning resource allocation scheme 2, to find a resource to replace the removed or discarded resource for SL PRS transmission, the UE performs another sensing process. When triggering this another sensing process, at least one of the following information is the same as the information in the initial sensing process: SL PRS resource ID, the number of symbols for SL PRS, multiple SL PRS resources (e.g., SL PRS resource ID), one or more PSCCH resources, an SL PRS resource packet including one or more SL PRS resources associated with the PSCCH resource, a resource pool, the priority of SL PRS transmission, the remaining packet delay budget, the number of sub-channels, a resource reservation interval, a subset of resources for preemption or re-evaluation, an indication of a resource selection mechanism. The removed / discarded resource and the resource(s) used to replace the removed / discarded resource are in different time domain units. The time domain unit can be a time slot.

[0070] In some arrangements, the first wireless communication device performs sensing in the first time domain unit and selects a first SL PRS resource, a first SL PRS resource packet, or a first PSCCH resource to send an SL PRS to the second wireless communication device, where at least one of the following cases is included: The first SL PRS resource packet includes one or more SL PRS resources associated with the PSCCH resource. The first wireless communication device determines a second SL PRS resource, a second resource packet, or a second PSCCH resource in the second time domain unit for replacing the first SL PRS resource, the first SL PRS resource packet, or the first PSCCH resource in the first time domain unit after preemption or re-evaluation. The second SL PRS resource, the second resource packet, or the second PSCCH resource is the same as the first SL PRS resource, the first SL PRS resource packet, or the first PSCCH resource, respectively.

[0071] In some arrangements, all the aperiodic SL PRS reservations indicated in an SCI have the same SL PRS resource ID. For a Tx UE in resource allocation scheme 2, for its SL PRS transmission, in order to achieve the transmission of SL PRS resource 1, a sensing process is performed. In an example where the Tx UE transmits the first occasion of the SCI / SL PRS in slot n and reserves SL PRS1 in slot n+t1, the Rx UE (or another UE performing sensing) receives the SCI and determines that the SL PRS resource in slot n+t1 is occupied. In an example where the Rx UE (or another UE performing sensing) receives another SCI from the Tx UE, the other SCI indicates that the same SL PRS resource (e.g., SL PRS resource 1) is reserved in the time-frequency domain resource (e.g., time occasion), which is different from those reservations indicated in the previous SCI received from the network. The Rx UE can determine that the previous reservation is disabled. In this example, between the previous SCI and the subsequent other SCI, one or more of the following items indicated by both of them can be the same: source ID, destination ID, broadcast type, resource reservation period, SL PRS priority. For example, the Rx UE (or another UE performing sensing) can determine that the resource is available for other transmissions or its own transmission.

[0072] Figure 7 FIG. 4 is a diagram showing an example allocation of time-domain resources and frequency-domain resources for transmitting SL PRS for multiple UEs in a structure 700 according to various arrangements. The horizontal dimension or x dimension represents time-domain resources, and the vertical dimension or y dimension represents frequency-domain resources. In some arrangements, the network configures an SCI 711, and the SCI 711 schedules SL PRS resource reservations (denoted as SL PRS resource 720a, SL PRS resource 720b, SL PRS resource 720c, and SL PRS resource 720d). In some examples, the reservations of SL PRS resource 720a, SL PRS resource 720b, SL PRS resource 720c, and SL PRS resource 720d have the same ID, e.g., SL PRS resource 1. Subsequently, the Rx UE (or another UE performing sensing) receives another SCI 712 from the Tx UE, and the other SCI 712 indicates that some of the same SL PRS resources (e.g., SL PRS resource 720b and SL PRS resource 720d) are reserved in the time-frequency domain resource (e.g., time occasion), which is different from the reservations indicated in the previous SCI 711 received from the network. The Rx UE can determine that the reservation of the previous SCI 711 is disabled. For example, the Rx UE (or another UE performing sensing) can determine that resources 720a and 720c are available for other transmissions or its own transmission.

[0073] In an example where a Rx UE (another UE performing sensing) receives another SCI from a Tx UE, the another SCI indicates that a different SL PRS resource (e.g., SL PRS resource 2) is reserved in a time-frequency domain resource (e.g., a time occasion), which is different from the reservation indicated in a previous SCI received from the network. The Rx UE may determine that the previous reservation is valid. In this example, between the previous SCI and the subsequent another SCI, one or more of the following items indicated by both may be the same: source ID, destination ID, broadcast type, resource reservation period, or SL PRS priority.

[0074] Figure 8 FIG. is a diagram showing an example allocation of time domain resources and frequency domain resources for transmitting SL PRS for multiple UEs in a structure 800 according to various arrangements. The horizontal dimension or x-dimension represents time domain resources, and the vertical dimension or y-dimension represents frequency domain resources. In some arrangements, the network configures an SCI 811, and the SCI 811 schedules SL PRS resource reservations (denoted as SL PRS resource 820a and SL PRS resource 820b). In some examples, the reservations of SL PRS resource 820a and SL PRS resource 820b have the same ID, e.g., SL PRS resource 1. Subsequently, a Rx UE (or another UE performing sensing) receives another SCI 812 from a Tx UE, and the another SCI 812 indicates that some SL PRS resources (e.g., SL PRS resource 830a and SL PRS resource 830b) in a different SL PRS resource are reserved in a time-frequency domain resource (e.g., a time occasion), which is different from the reservation indicated in the previous SCI 811 received from the network. In some examples, the reservations of SL PRS resource 830a and SL PRS resource 830b have the same ID, e.g., SL PRS resource 2. The Rx UE may determine that the reservation of the previous SCI 811 is valid.

[0075] Generally speaking, from the perspective of the Rx UE, the SL PRS resource ID indicated in the SCI or implied by the position of the SCI has an impact on whether the Rx UE determines that the SL PRS reservation in the previous SCI from the network is valid.

[0076] In some arrangements, the aperiodic SL PRS reservation indicated in an SCI can be for different SL PRS resources. For example, in an example where the Rx UE (or another UE performing sensing) receives another SCI from the Tx UE, and this other SCI indicates that the same SL PRS resource (e.g., SL PRS resource 2) is reserved in time-frequency domain resources (e.g., a time occasion) that is different from the location of the reservation of the same SL PRS resource indicated in a previous SCI, the Rx UE can assume that the previous reservation from the network is disabled. In this example, between the previous SCI and the subsequent other SCI, one or more of the following items indicated by both can be the same: source ID, destination ID, broadcast type, resource reservation period, SL PRS priority.

[0077] Figure 9 FIG. Figure 9 is a diagram showing an example allocation of time domain resources and frequency domain resources for transmitting SL PRS for multiple UEs in a structure 900 according to various arrangements. The horizontal dimension or x-dimension represents time domain resources, and the vertical dimension or y-dimension represents frequency domain resources. In some arrangements, the network configures an SCI 911 that schedules SL PRS resource reservations (denoted as SL PRS resources 920a and 930b). In some examples, the reservation of SL PRS resource 920a has a first ID, e.g., SL PRS resource 1, while SL PRS resource 930b has a second ID, e.g., SL PRS resource 2. Subsequently, the Rx UE (or another UE performing sensing) receives another SCI 912 from the Tx UE, and this other SCI 912 indicates that SL PRS resources 930a, 930b, and 930c are reserved in time-frequency domain resources (e.g., a time occasion) that is different from the reservation indicated in the previous SCI 911 received from the network. In some examples, the reservations of SL PRS resources 930a, 930b, and 930c have the same ID. The Rx UE can determine that the reservation of the previous SCI 911 is disabled. For example, the Rx UE (or another UE performing sensing) can determine that resource 910a is available for other transmissions or its own transmissions.

[0078] In some arrangements, the Rx UE (or another UE performing sensing) receives another SCI from the Tx UE, and this other SCI indicates that one or more different SL PRS resources (e.g., SL PRS resources 3, 4) are reserved compared to the SL PRS resources indicated in a previous SCI. The Rx UE may assume that the previous reservation is valid. In this example, between the previous SCI and the subsequent other SCI, one or more of the following items indicated by both may be the same: source ID, destination ID, broadcast type, resource reservation period, SL PRS priority. For example, in Figure 8 after receiving SCI 811, the Rx UE (or another UE performing sensing) receives another SCI 812 from the Tx UE, and this other SCI 812 indicates that one or more different SL PRS resources (e.g., SL PRS resource 830a and SL PRS resource 830b) are reserved in time-frequency domain resources (e.g., time occasion). In some examples, the ID of the reservation for SL PRS resource 820a is 1, the ID of the reservation for SL PRS resource 830a is 2, the ID of the reservation for SL PRS resource 820b is 3, and the ID of the reservation for SL PRS resource 830b is 4. The Rx UE may determine that the reservation of the previous SCI 811 is valid.

[0079] In some arrangements, the Tx UE transmits PSCCH / SCI resource 1 in time slot n and reserves one or more SL PRS resources in future time slots. The Rx UE (or another UE performing sensing) receives this SCI and assumes that the (one or more) SL PRS resources in the future time slots are occupied. In response to the Rx UE (or another UE performing sensing) receiving another PSCCH / SCI resource from the Tx UE in a time slot different from time slot n that indicates an SL PRS reservation and this other PSCCH / SCI resource is the same as the previous PSCCH / SCI resource 1 in time slot n, the Rx UE may assume that the previous reservation is disabled. In other words, the SL PRS reservation of the new PSCCH / SCI may override the SL PRS reservation of the previous PSCCH / SCI. In this example, between the previous PSCCH / SCI and the subsequent other PSCCH / SCI, one or more of the following items may be the same: source ID, destination ID, broadcast type, resource reservation period, or SL PRS priority.

[0080] In some arrangements, the Tx UE transmits PSCCH / SCI resource 1 in time slot n and reserves one or more SL PRS resources in future time slots. The Rx UE (or another UE performing sensing) receives the SCI and assumes that the (one or more) SL PRS resources in future time slots are occupied. In response to the Rx UE (or another UE performing sensing) receiving another PSCCH / SCI resource from the Tx UE in a time slot different from time slot n that indicates the SL PRS reservation and the other PSCCH / SCI resource is different from the previous PSCCH / SCI resource 1 in time slot n, the Rx UE may assume that the previous reservation remains valid. In this example, between the previous PSCCH / SCI and the subsequent other PSCCH / SCI, one or more of the following may be the same: source ID, destination ID, broadcast type, resource reservation period, or SL PRS priority.

[0081] In some arrangements, method 300 further includes: sending, by a first UE (e.g., UE 104a), an SCI to a plurality of UEs to indicate the number of SL PRS reservations for transmissions with or without periodic reservation. In some arrangements, the resources for transmitting the SCI and the SL PRS resources in the time domain unit are mapped through a one-to-one mapping relationship. In some arrangements, the resources for transmitting the SCI and a plurality of SL PRS resources in the time domain unit are mapped through a one-to-many mapping relationship. In some arrangements, a second UE (e.g., UE 104b) is one of the plurality of UEs. In some arrangements, the SCI reserves only the SL PRS resources belonging to the SL PRS resource packet. The SL PRS resource packet includes one or more SL PRS resources mapped to the resources for transmitting the SCI.

[0082] In some arrangements, method 300 further includes: sending, by a first wireless communication device, an SCI to one of a plurality of UEs, the SCI including the number of SL PRS resource IDs. The number of SL PRS resource IDs is 1 less than the number of SL PRS reservations for transmissions without periodic reservation.

[0083] In some arrangements, method 300 further includes: sending, by a first UE, an SCI to one of a plurality of UEs, the SCI including the number of SL PRS resource IDs. The number of SL PRS resource IDs is equal to the number of SL PRS reservations for transmissions without periodic reservation. In some arrangements, method 300 further includes: sending, by a first UE, an SCI to one of a plurality of UEs, the SCI including one or more lists of information. The information includes at least one or more of the following: source ID, destination ID, resource reservation period, SL PRS priority, or broadcast type.

[0084] In some arrangements, for transmitting SL PRS, the physical layer of a first UE determines at least one of the following: one or more SL PRS resources, resources for transmitting SCI, the number of time domain resources, the resource pool in which one or more SL PRS resources will be transmitted, the priority of SL PRS transmission, the remaining packet delay budget, the resource reservation period, or a subset of resources for preemption and re-evaluation.

[0085] In some arrangements, for transmitting SL PRS, the higher layer of a first wireless communication device determines at least one of the following: one or more SL PRS resources, resources for transmitting SCI, the number of time domain resources, the resource pool in which one or more SL PRS resources will be transmitted, the priority of SL PRS transmission, the remaining packet delay budget, the resource reservation period, or a subset of resources for preemption and re-evaluation. The higher layer includes at least one of the MAC layer, the RRC layer, or the NAS layer.

[0086] In some arrangements, a second UE (e.g., UE 104b) receives a reservation of one or more first SL PRS resources from a first UE (e.g., UE 104a) via a first SCI in a first time domain unit. The second UE receives a reservation of one or more SL PRS resources that are the same as the one or more first SL PRS resources from a first wireless communication device via a second SCI in a second time domain unit. The second UE determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is invalid.

[0087] In some arrangements, a second UE (e.g., UE 104b) receives a reservation of one or more first SL PRS resources from a first UE via a first SCI in a first time domain unit. The second UE receives a reservation of one or more SL PRS resources that are different from the one or more first SL PRS resources from the first UE via a second SCI in a second time domain unit. The second UE determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is valid.

[0088] In some arrangements, a second UE (e.g., UE 104b) receives a reservation of one or more first SL PRS resources from a first UE via a first SCI in a first time domain unit. The second UE receives a reservation of one or more second SL PRS resources from the first UE via a second SCI in a second time domain unit. The first SCI and the second SCI are the same PSCCH resource. The second UE determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is invalid.

[0089] In some arrangements, a second UE (e.g., UE 104b) receives a reservation of one or more first SL PRS resources from a first UE (e.g., UE 104a) via a first SCI in a first time domain unit. The second UE receives a reservation of one or more second SL PRS resources from the first wireless communication device via a second SCI in a second time domain unit. The first SCI and the second SCI are different PSCCH resources. The second UE determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is valid.

[0090] In some arrangements, the first SCI and the second SCI have at least one of the following: the same source ID, the same destination ID, the same broadcast type, the same resource reservation period, or the same SL PRS priority.

[0091] In some arrangements, the impact of synchronization errors between UEs can be mitigated. In some examples, in resource allocation scheme 2, a server UE can be used to determine a positioning method, select an anchor UE, assist in allocation, and / or perform position calculation. The server UE can be used to transmit a Channel Access Priority Class (CAPC) configuration to a Tx UE. In some examples, either the anchor UE or the target UE or any UE can serve as the server UE. For example, in SL-Time Difference of Arrival (TDOA) positioning of class DL, multiple anchor UEs send SL PRSs to the target UE respectively. Once an anchor UE successfully occupies a Channel Occupancy Time (COT), the anchor UE can share the COT with other involved anchor UEs. In some examples, all anchor UEs involved in an SL-TDOA positioning are in a group.

[0092] Synchronization information exchange of an anchor UE between a UE (e.g., the first UE) and a Location Management Function (LMF) or another UE (the second UE) can be supported to mitigate the impact of synchronization errors. The time synchronization information can include information of a reference UE (e.g., UE ID, reference time, and quality of the timing of the reference UE, etc.) and the relative synchronization time offset (including quality) between the reference UE and a list of anchor UEs.

[0093] In some examples, the LMF transmits the synchronization information of the anchor UE to the UE via Long-Term Evolution Positioning Protocol (LPP) signaling or via SLPP signaling for UE-based positioning. Figure 10is a signaling diagram showing an example synchronization method 1000 for UE-based positioning according to various arrangements. According to various arrangements, the method 1000 can be executed by an anchor UE 1002, an LMF 1004, and a server UE 1006. Although only one anchor UE 1002 is shown and described, the method 1000 is applicable to multiple anchor UEs, where each anchor UE can be the anchor UE 1002.

[0094] In some arrangements, at 1010, the LMF 1004 sends a UE information request 1010 to the anchor UE 1002. At 1020, the anchor UE 1002 sends a UE information report (e.g., UE information) to the LMF 1004 via LPP signaling or via SLPP signaling. The UE information may include at least one of the following information for the anchor UE 1002: UE ID, timing information (e.g., System Frame Number (SFN), Direct Frame Number (DFN)), SFN initial time, synchronization reference source, NR Physical Layer Cell ID (PCI), NR Cell Global Identify (CGI), NR Absolute Radio Frequency Channel Number (ARFCN), SL PRS configuration, geographical coordinates, Antenna Reference Point (ARP) geographical coordinates, UE type (e.g., whether the anchor UE 1002 can be a server UE), UE Tx Timing Error Group (TEG) association, and UE Tx ARP association, etc.

[0095] In some examples, at 1010, the LMF 1004 may send a UE information request to the anchor UE 1002 via LPP or via SLPP. The UE information request signaling may include one or more of the following: UE ID, timing information (e.g., SFN, DFN), SFN initial time, synchronization reference source, NR PCI, NR CGI, NR ARFCN, SL PRS configuration, geographical coordinates, ARP geographical coordinates, UE type (e.g., whether the anchor UE can be a server UE), UE Tx TEG association, UE Tx ARP association.

[0096] In some examples, the serving UE 1006 may send a synchronization information request to the LMF 1004 via LPP or via SLPP to obtain information about the timing offset between different anchor UEs 1002. For example, at 1030, the serving UE 1006 sends a request for synchronization information of the anchor UE 1002 to the LMF 1004. At 1040, the LMF 1004 sends the information of the anchor UE 1002 received at 1020 to the serving UE 1006.

[0097] In some examples, another UE (e.g., a second UE) transmits the synchronization information of the anchor UE to a UE (a first UE) via the sidelink positioning protocol (SLPP). Figure 11 FIG. is a signaling diagram illustrating an example synchronization method 1100 for UE-based positioning according to various arrangements. According to various arrangements, the method 1100 may be performed by the anchor UE 1002, the UE 1104, and the serving UE 1006. Although only one anchor UE 1002 is shown and described, the method 1100 is applicable to multiple anchor UEs, where each anchor UE may be the anchor UE 1002.

[0098] At 1110, the UE 1104 sends a UE information request 1110 to the anchor UE 1002 via SLPP. At 1120, the anchor UE 1002 transmits a UE information report 1120 including UE information to the UE 1104 via SLPP. The UE information includes at least one of the following information of the anchor UE 1002: UE ID, timing information (e.g., SFN, DFN), SFN initial time, synchronization reference source, NR PCI, NR CGI, NR ARFCN, SL PRS configuration, geographical coordinates, ARP geographical coordinates, UE type (e.g., whether the anchor UE can be a serving UE), UE Tx TEG association, or UE Tx ARP association. The UE information request signaling may include one or more of the following: UE ID, timing information (e.g., SFN, DFN), SFN initial time, synchronization reference source, NR PCI, NR CGI, NR ARFCN, SL PRS configuration, geographical coordinates, ARP geographical coordinates, UE type (e.g., whether the anchor UE can be a serving UE), UE Tx TEG association, or UE Tx ARP association.

[0099] In some examples, the serving UE 1006 may send a synchronization information request to the UE 1104 via LPP to obtain information about the time offset between different anchor UEs 1002. For example, at 1130, the serving UE 1006 sends a request for synchronization information of the anchor UE 1002 to the UE 1104. At 1140, the UE 1104 sends the information of the anchor UE 1002 received at 1120 to the serving UE 1006.

[0100] In some arrangements, the method 300 further includes: receiving, by a first UE (e.g., UE 104a), a UE information request from a device via LPP or SLPP. In some arrangements, the method 300 further includes: transmitting, by a first wireless communication device, a UE information report to the device via LPP or SLPP.

[0101] In some arrangements, the UE information request or the UE information report includes at least one of the following information for an anchor UE: UE ID, SFN, DFN, SFN initial time, synchronization reference source, NR PCI, NR CGI, NR ARFCN, SL PRS configuration, geographical coordinates, ARP geographical coordinates, UE type, UE Tx TEG association, or UE Tx ARP association.

[0102] In some examples, the device includes an LMF. In some examples, the device includes another UE. In some examples, the method 300 further includes: sending, by the device, synchronization information between a plurality of UEs and a reference UE or between a plurality of UEs and a reference network device to the UE based on the UE information reports of the plurality of UEs. The first UE is one of the plurality of UEs.

[0103] In some examples, the synchronization information includes at least one of the following: information of the reference UE, reference UE ID, reference timing of the reference UE, SFN of the reference UE, DFN of the reference UE, UTC (Coordinated Universal Time) time, physical cell ID, global cell ID, ARFCN, quality of the timing of the reference UE, UE IDs of the plurality of UEs, synchronization timing offset between the reference and one of the plurality of UEs, or quality of the synchronization timing offset.

[0104] In some arrangements, for the SL PRS sequence ID configuration, both the one provided by the higher layer is supported and the one based on the 12 least significant bits (LSBs) cyclic redundancy check (CRC) of the PSCCH associated with the SL PRS is supported Both PSCCH DMRS and SL PRS can be candidate reference signals (RS) for sensing. During the sensing process, the sensing RS can be pre-configured or configured for each resource pool and is used to derive the Reference Signal Received Power (RSRP) to further compare the measured RSRP with a threshold.

[0105] In some examples, the SL PRS has a larger bandwidth and can thus produce a more accurate RSRP measurement compared to the RSRP based on PSCCH DMRS. To use the SL PRS as the sensing RS and avoid resource conflicts simultaneously, the UE cannot measure the SLPRS RSRP without sequence ID information.

[0106] In some examples, is based on the 12 LSB bits CRC of the PSCCH associated with the SLPRS, and the SL PRS sequence ID configured by the higher layer is not allowed.

[0107] In some examples, the UE has the SL PRS sequence ID provided by the higher layer, and these UEs broadcast their SL PRS sequence IDs. The broadcast signaling can be at least one of SCI, SLPP, etc. Each SL PRS sequence ID broadcast by such UEs can be associated with the SLPRS resource or the transmission location of the SLPRS resource. The transmission location can be the slot number, symbol number, frequency domain allocation, etc.

[0108] The ARP location information of the anchor UE can be included in the anchor UE location information. The ARP location information of the anchor UE is the relative position of the ARP to the anchor UE, and each ARP location is associated with an ARP ID. In addition, the anchor UE can provide the ARP location information of the SL PRS resource in the auxiliary data.

[0109] In some arrangements, the first UE (e.g., UE 104a) sends the SL PRS to the second UE (e.g., UE104b) based on the SL PRS sequence ID. The first UE receives the SL PRS sequence UE from the higher layer through signaling. The signaling includes at least one of the following: LPP from the LMF, SLPP from the LMF or UE, RRC from BS102, or the SL PRS resource configuration is pre-configured. The higher layer of the first wireless communication device, where the higher layer includes at least one of the following: MAC layer, RRC layer, or NAS layer. In some arrangements, the first UE broadcasts the SL PRS sequence ID to multiple wireless communication devices through at least one of SCI or SLPP.

[0110] In some examples, method 300 further includes: reporting ARP location information by the first UE or the second UE to a device. The ARP location information includes at least a relative location of at least one ARP with respect to the location of the first UE or the second UE. Each ARP location is associated with an ARPID. In some examples, the device includes an LMF or another UE.

[0111] In some arrangements, in the SLPRS resource allocation scheme 1, the sender UE can receive SL PRS resource allocation from the gNB through Downlink Control Information (DCI), rather than selecting resources through sensing or random resource selection. Both dedicated resource pools and shared resource pools can be used for SL positioning. In some arrangements, the DCI can distinguish between dedicated resource pools and shared resource pools.

[0112] In some arrangements, the same DCI format or the same Radio Network Temporary Identifier (RNTI) (e.g., a DCI format with a CRC scrambled by the same RNTI) is used for both dedicated resource pools and shared resource pools. In some examples, a resource pool index indicator can be used to indicate whether the fields / indicators included in the DCI are for SL PRS transmission in a dedicated resource pool or for SL PRS transmission in a shared resource pool. In some examples, the number of bits occupied by the resource pool index is related to the total number of both shared resource pools and dedicated resource pools used for transmitting SL PRS.

[0113] In some arrangements, the same DCI format or the same RNTI (e.g., a DCI format with a CRC scrambled by the same RNTI) is used for both dedicated resource pools and shared resource pools. In some examples, an additional one-bit "SLPRS resource pool type" can be introduced to indicate whether the DCI is for scheduling SL PRS transmission in a dedicated resource pool or a shared resource pool. If the shared resource pool is indicated, the number of bits occupied by the "resource pool index" is related to the total number of shared resource pools used for transmitting SL PRS; if the dedicated resource pool is indicated, the number of bits occupied by the "resource pool index" is related to the total number of both shared resource pools and dedicated resource pools used for transmitting SL PRS; in some examples, the DCI format can be DCI format 3-0 or a new DCI format.

[0114] In some arrangements, depending on whether the UE is scheduled to transmit SL PRS in a shared resource pool or a dedicated resource pool, different DCI formats or different RNTIs (e.g., DCI formats with CRC scrambled by different RNTIs) are respectively applied to schedule SL PRS transmission in the shared resource pool or the dedicated resource pool. Whichever method is applied to the DCI format / RNTI design for the dedicated resource pool and the shared resource pool, at least one of the following designs for specific fields in the DCI should be applied. If the dedicated resource pool and the shared resource pool share the same DCI format or the same RNTI, then if the DCI is intended for the dedicated resource pool, only a few fields related to scheduling SL PRS in the dedicated resource pool are activated or enabled or transmitted via the DCI; if the DCI is intended for the shared resource pool, only a few fields related to scheduling SL PRS in the shared resource pool are activated or enabled or transmitted via the DCI.

[0115] Figure 12 is a flowchart showing an example method 1200 for configuring and communicating SL PRS and SCI according to various arrangements. Method 1200 can be executed using system 100 and system 200.

[0116] At 1210, a first UE (e.g., UE 104a) receives DCI from a network node (e.g., BS 102), the DCI carrying information for scheduling SL PRS. At 1220, the first UE sends SCI and SL PRS to a second UE (e.g., UE 104b) based on the information included in the DCI. In some arrangements, the DCI is used to schedule the first UE's SL PRS transmission in a dedicated resource pool or a shared resource pool. In some arrangements, the same DCI format or the same RNTI is used for the DCI that schedules SL PRS in the dedicated resource pool and the shared resource pool. An indicator for indicating the resource pool type is indicated in the DCI. In some arrangements, the DCI for scheduling SL PRS in the dedicated resource pool and the DCI for scheduling SL PRS in the shared resource pool have different DCI formats or are accompanied by CRC scrambled by different RNTIs.

[0117] In some arrangements, if the resource pool index field indicates that the DCI is used to schedule SLPRS transmission in a shared resource pool, if the SL PRS resource pool type field indicates that the DCI is used to schedule SL PRS transmission in a shared resource pool, or if the DCI format or RNTI implies / indicates that the DCI is used to schedule SL PRS transmission in a shared resource pool, then one or more of the following should be used for the DCI design: (1) An SL data indicator can be introduced in the DCI. For example, the number of bits of the SL data indicator is 1, which indicates whether the DCI is used to schedule only SL PRS transmission or both SL PRS transmission and SL data transmission; (2) There is only one DCI format for the shared resource pool, where different RNTIs are used for the following two cases: only scheduling SL PRS transmission or scheduling both SL PRS transmission and SL data transmission; (3) In order to indicate which SL PRS resource is scheduled for transmission, a new field "SL PRS resource ID" can be introduced in the DCI, where the number of bits of the field "SL PRS resource ID" is related to the total number of SL PRS resources configured for transmission in the shared resource pool; (4) In order to indicate which SL PRS resource is scheduled for transmission and whether SL data is also scheduled, a new field "SL data and SL PRS resource field" can be introduced in the DCI, where the number of bits of the field "SL PRS resource ID" is related to the total number of SL PRS resources configured for transmission in the shared resource pool; for example, "0" represents SL PRS resource 1 with SL data, and "1" represents SL PRS resource 2 with SL data,..., "n" represents SL PRS resource 1 without SL data, "n + 1" represents SL PRS resource 2 without SL data,...; (5) In order to indicate which SL PRS resource is scheduled for transmission, the SL PRS resource ID can be associated or mapped with the HARQ process number. This mapping relationship can be configured in RRC signaling, or depending on pre-configuration, in some examples, the mapping relationship between the HARQ process number and the SL PRS resource ID can be configured in the resource pool, or through another dedicated RRC signaling. In this case, if the DCI is used to schedule only SL PRS transmission, the HARQ process number field can be used to indicate the SL PRS resource ID. If the DCI is used to schedule both SL PRS transmission and SL data transmission, the HARQ process number field can be used to indicate the HARQ process number for SL communication and to indicate the SL PRS resource ID for SL positioning; (6) If the SL PRS is only scheduled through the DCI, the PUCCH indicator may not be included in the DCI, or if the PUCCH resource indicator is included in the DCI, only ACK feedback is expected from the UE to the gNB.

[0118] In some arrangements, for a shared resource pool, a new second-stage SCI (2 nd stage SCI) is introduced to indicate whether it is SL PRS or both SL PRS and SL-SCH (e.g., SL data for SL communication). At least one or more of the following should be indicated in this new second-stage SCI: (1) An SL data indicator can be introduced in the SCI. For example, the number of bits of the SL data indicator is 1, which indicates whether the SCI is for scheduling only SL PRS transmission or for scheduling both SL PRS transmission and SL data transmission; (2) To indicate which SL PRS resource is scheduled for transmission, a new field "SL PRS resource ID" can be introduced in the SCI, where the number of bits of the field "SL PRS resource ID" is related to the total number of SL PRS resources configured for transmission in the shared resource pool; (3) To indicate both which SL PRS resource is scheduled for transmission and whether SL data is also scheduled, a new field "SL data and SL PRS resource field" can be introduced in the SCI, where the number of bits of the field "SL PRS resource ID" is related to the total number of SL PRS resources configured for transmission in the shared resource pool; for example, "0" represents SL PRS resource 1 with SL data, and "1" represents SL PRS resource 2 with SL data,..., "n" represents SL PRS resource 1 without SL data, "n + 1" represents SL PRS resource 2 without SL data; (4) To indicate which SL PRS resource is scheduled for transmission, the SL PRS resource ID can be associated with or mapped to the HARQ process number. This mapping relationship can be configured in RRC signaling or, depending on pre-configuration, in some examples, the mapping relationship between the HARQ process number and the SL PRS resource ID can be configured in the resource pool or through another dedicated RRC signaling. In this case, if the SCI is used for scheduling only SL PRS transmission, the HARQ process number field can be used to indicate the SL PRS resource ID. If the SCI is used for scheduling both SL PRS transmission and SL data transmission, the HARQ process number field can be used to indicate the HARQ process number for SL communication and to indicate the SL PRS resource ID for SL positioning.

[0119] In some arrangements, if DCI or SCI is used to indicate SL PRS transmission of a wireless communication device in a shared resource pool, the DCI includes or applies at least one of the following: RNTIs that are different for two cases: scheduling only SL PRS transmission or scheduling both SL PRS transmission and SL data transmission; a field for indicating whether the DCI is for a dedicated resource pool or a shared resource pool; a field for indicating a time interval; a field for indicating frequency resource allocation; a field for indicating time resource allocation; a field for indicating whether the DCI is for scheduling only SL PRS transmission or for scheduling both SL PRS transmission and SL data transmission; a field for indicating one or more SL PRS resource IDs; a field for indicating a Hybrid Automatic Repeat request (HARQ) process number to indicate either the HARQ process number or both the HARQ process number and the SL PRS resource ID, wherein there is a (pre)-configured mapping relationship between the HARQ process number and the SL PRS resource ID; a field for indicating a PUCCH resource, wherein if only SL PRS transmission is scheduled, the wireless communication device only sends an Acknowledgement (ACK) to the network node in the PUCCH; a field for indicating a configuration index.

[0120] In some arrangements, if the resource pool index field indicates that the DCI is used to schedule SLPRS transmission in a dedicated resource pool, or if the SL PRS resource pool type field indicates that the DCI is used to schedule SL PRS transmission in a dedicated resource pool, or if the DCI format or RNTI implies / indicates that the DCI is used to schedule SL PRS transmission in a dedicated resource pool, then at least one or more of the following methods should be used for the DCI design: (1) If there is a (pre)-configured one-to-one mapping relationship between the PSCCH resource and the associated SL PRS resource, and if the non-periodic reservation in the SCI is the same SL PRS resource, the DCI needs to indicate the SCI location of the first / initial SL PRS transmission. For example, the DCI indicates the lowest index of the subchannel allocation for the initial / first transmission, or indicates the PSCCH resource ID, or indicates the lowest PRB index and the number of PRBs of the PSCCH. There is no need to include a frequency resource allocation field or an SL PRS resource ID field in the DCI; (2) If there is a (pre)-configured one-to-one mapping relationship between the PSCCH resource and the associated SL PRS resource, and if the non-periodic reservation in the SCI is the same SL PRS resource, the DCI needs to indicate information about the SL PRS resource. For example, the DCI may include an SL PRS resource ID field, and the number of bits in the SL PRS resource ID field is related to the total number of SL PRS resources configured for transmission in the dedicated resource pool.There is no need to include a frequency resource allocation field or an SCI location field for the first / initial SL PRS transmission in the DCI; (3) The DCI indicates the frequency resource allocation field and the SCI location field for the first / initial SL PRS transmission. For example, if there is a (pre)-configured one-to-one mapping relationship between the PSCCH resource and the associated SL PRS resource, and if the non-periodic reservation in the SCI is for different SL PRS resources; (4) The DCI indicates one or more SL PRS resource ID fields. For example, if there is a (pre)-configured one-to-one mapping relationship between the PSCCH resource and the associated SL PRS resource, and if the non-periodic reservation in the SCI is for different SL PRS resources; (5) The DCI indicates the SL PRS resource ID field and the SCI location field for the first / initial SL PRS transmission. For example, if there is a (pre)-configured one-to-many mapping relationship between the PSCCH resource and one or more associated SL PRS resources, and if the non-periodic reservation in the SCI is for the same SL PRS resource; (6) The DCI indicates the SL PRS resource ID field, the SCI location field for the first / initial SL PRS transmission, and the frequency resource allocation field. For example, if there is a (pre)-configured one-to-many mapping relationship between the PSCCH resource and one or more associated SL PRS resources, and the non-periodic reservation in the SCI is for different SL PRS resources.

[0121] In some arrangements, if DCI is used to indicate SL PRS transmission by a wireless communication device in a dedicated resource pool, the DCI includes or applies at least one of the following: a field for indicating whether the DCI is for a dedicated resource pool or a shared resource pool; a field for indicating a time interval; a field for indicating one or more SL PRS resource IDs; a SCI location field for indicating the first / initial SL PRS transmission; a field for indicating frequency resource allocation; a field for indicating time resource allocation; a field for indicating one or more PSCCH resources; a field for indicating a hybrid automatic repeat request (HARQ) process number to indicate the HARQ process number or to indicate both the HARQ process number and the SL PRS resource ID, where there is a (pre)-configured mapping relationship between the HARQ process number and the SL PRS resource (e.g., SL PRS resource ID); a field for indicating a hybrid automatic repeat request (HARQ) process number to indicate the HARQ process number or both the HARQ process number and the PSCCH resource ID, where there is a (pre)-configured mapping relationship between the HARQ process number and the PSCCH resource (e.g., PSCCH resource ID), the PSCCH resource can indicate the frequency domain and time domain configuration of the SCI, and the mapping relationship between the HARQ process or the SL process and the SL PRS / PSCCH resource can be configured in RRC signaling or depends on pre-configuration; a field for indicating a configuration index.

[0122] At 1205, a network node (e.g., BS102) sends DCI to a first UE (e.g., UE 104a), and the DCI carries information for scheduling SL PRS.

[0123] In some examples, for scheduling of only SL-PRS or scheduling of SL-PRS + data, a new RNTI can be introduced, e.g., a DCI format 3_0 with a CRC scrambled by SL-PRS-RNTI or SL-PRS-CS-RNTI (Configured Scheduling-RNTI, semi-persistent scheduling RNTI). It should be noted that the traditional RNTI of DCI format 3_0 can still be reused for scheduling of only data.

[0124] In some examples, for a shared resource pool, at least one new bit should be introduced to indicate whether the scheduling is for SL-PRS only or for SL-PRS + data. In the case of scheduling SL-PRS only, the UE can ignore some fields, such as the new data indicator, the PSFCH (Physical Sidelink Feedback Channel)-to-HARQ (PSFCH-to-HARQ) feedback timing indicator, and the PUCCH resource indicator. Otherwise, SL-PRS and data are scheduled in the same time slot(s). In both cases, BS102 should implicitly or explicitly indicate to the UE the appropriate SL-PRS resources that meet the location requirements. Otherwise, the UE randomly selects SL-PRS resources on its own, and BS102 is not aware of this because BS102 cannot predict how many symbols in the allocated PRB are reserved for SL-PRS, so some problems may occur when BS102 determines the number of PRBs / symbols to be allocated for data transmission through DCI 3_0. To save DCI overhead, the existing HARQ process number field can be used to implicitly indicate the SL-PRS resources, where a one-to-one mapping can be associated through (pre-)configuration.

[0125] In some examples, for a dedicated resource pool, it is similar to the case of SL-PRS for the shared resource pool only, or may be simpler than the case of SL-PRS for the shared resource pool only. If a one-to-one mapping between the SCI resource and the SL-PRS resource is introduced, the PRS resource index can be implicitly indicated by the SCI frequency position.

[0126] In some examples, in the dynamic authorization type resource allocation of Scheme 1, DCI 3_0 is used for both the dedicated resource pool and the shared resource pool together with the new RNTI SL-PRS-RNTI or SL-PRS-CS-RNTI. For the dedicated resource pool, the SL-PRS resource ID is implicitly indicated by the frequency position of the SCI. For the shared resource pool, the SL-PRS resource ID is implicitly indicated by the HARP process ID.

[0127] In some examples, in the dynamic authorization type resource allocation of Solution 1, the specific fields of DCI 3_0 are as follows or at least include one or more of the following: a new bit for indicating whether to schedule only SL-PRS or to schedule SL-PRS + data; a resource pool index for indicating a shared resource pool or a dedicated resource pool; a time interval; a HARQ process and a PRS resource indicator, where a one-to-one mapping can be (pre)-configured between the HARQ process ID and the PRS resource ID, and for the case of only SL PRS, this field is only used for PRS resource indication, while for a dedicated resource pool, this field is ignored by the UE; the lowest index of the subchannel allocation for the initial transmission; the SCI format 1-A field for frequency resource allocation; the SCI format 1-A field for time resource allocation; a configuration index. For a dedicated resource pool or a shared resource pool that schedules only SL-PRS, the UE ignores at least one of the following fields: a new data indicator, a PSFCH to HARQ feedback timing indicator, a PUCCH resource indicator, a count side link allocation index.

[0128] Although various arrangements of the present solution have been described above, it should be understood that these arrangements are provided only as examples and are not limiting. Similarly, various diagrams may depict example architectures or configurations, aiming to enable those of ordinary skill in the art to understand the example features and functions of the present solution. However, these persons will understand that the solution is not limited to the example architectures or configurations shown, but can be implemented using various alternative architectures and configurations. In addition, those of ordinary skill in the art will understand that one or more features of some arrangements can be combined with one or more features of another arrangement described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the above-described illustrative arrangements.

[0129] It should also be understood that any reference to elements using names such as "first", "second", etc. generally does not limit the number or order of these elements. Instead, these names can be used herein as a convenient means for distinguishing between two or more elements or two or more instances of an element. Therefore, referring to a first element and a second element does not mean that only two elements can be adopted, nor does it mean that the first element must precede the second element in a certain way.

[0130] In addition, those of ordinary skill in the art will understand that various different techniques and methods can be used to represent information and signals. For example, data, instructions, commands, information, signals, bits, and symbols that may be mentioned in the above description can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0131] Those of ordinary skill in the art will further appreciate that any of the various illustrative logical blocks, modules, processors, means, circuits, methods, and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., digital implementation, analog implementation, or a combination of both), firmware, various forms of program or design code incorporating instructions (which may be referred to herein, for convenience, as "software" or "software modules"), or any combination of these technologies. To clearly illustrate the interchangeability of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have generally been described above in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these technologies, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in various ways for each particular application, but such implementation decisions do not result in a departure from the scope of the present disclosure.

[0132] In addition, those of ordinary skill in the art will understand that the various illustrative logical blocks, modules, devices, components, and circuits described herein can be implemented in or performed by an integrated circuit (IC), which may include a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logical blocks, modules, and circuits may also include antennas and / or transceivers to communicate with various components within a network or within a device. A general-purpose processor may be a microprocessor, but alternatively, the processor may be any conventional processor, controller, or state machine. The processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other suitable configuration for performing the functions described herein.

[0133] If these functions are implemented in software form, they can be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the methods or algorithms disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media include computer storage media and communication media, and communication media include any medium capable of transferring a computer program or code from one place to another. Storage media can be any available medium accessible by a computer. By way of example and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage devices, magnetic disk storage devices or other magnetic storage devices, or any other medium that can be used to store the required program code in the form of instructions or data structures and can be accessed by a computer.

[0134] In this document, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purposes of discussion, various modules are described as discrete modules; however, it will be apparent to those of ordinary skill in the art that two or more modules can be combined to form a single module that performs the associated functions according to the arrangement of the present solution.

[0135] Furthermore, memory or other storage devices and communication components can also be employed in the arrangement of the present solution. It will be understood that, for clarity, the above description has described the arrangement of the present solution in terms of different functional units and processors. However, it will be apparent that, without detracting from the present solution, any suitable functional allocation can be made between different functional units, processing logic elements, or domains. For example, functions shown to be performed by separate processing logic elements or controllers can be performed by the same processing logic element or controller. Therefore, the reference to a particular functional unit is only a reference to a suitable means for providing the stated function and does not imply a strict logical or physical structure or organization.

[0136] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments without departing from the scope of the disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown herein, but should be accorded the widest scope consistent with the novel features and principles disclosed herein as recited in the appended claims.

Claims

1. A wireless communication method, comprising: receiving, by a first wireless communication device, an SL PRS resource configuration from a higher layer for communicating a sidelink positioning reference signal (SLPRS) in a time domain unit; sending, by the first wireless communication device, the SLPRS to a second wireless communication device according to the SL PRS resource configuration.

2. The method according to claim 1, wherein There is at least the following situation: the time domain configuration of the SL PRS resources of the first wireless communication device is aligned with the time domain configurations of the SL PRS resources of multiple wireless communication devices; the SL PRS resources of the first wireless communication device and the SL PRS resources of the multiple wireless communication devices are time division multiplexed (TDMed), comb-based multiplexed, or TDM and comb-based multiplexed within the time domain unit; the SL PRS resources are configured in a resource pool, and the resource pool is a dedicated resource pool or a shared resource pool; the time domain unit is a time slot; and the SL PRS resource configuration is received from the higher layer by signaling, and the signaling includes at least one of the following: Long-Term Evolution Positioning Protocol (LPP) from a Location Management Function (LMF); Sidelink Positioning Protocol (SLPP) from the LMF or a wireless communication device; Radio Resource Control (RRC) or Media Access Control (MAC) from a base station (BS), the higher layer of the first wireless communication device, where the higher layer includes at least one of a MAC layer, an RRC layer, or a Non-Access Stratum (NAS) layer; or the SL PRS resource configuration is pre-configured.

3. The method according to claim 1, wherein The SL PRS resource configuration includes a time domain configuration, where the time domain configuration includes at least one of a time domain start point, a time domain length, or an SL PRS resource position in the time domain unit.

4. The method according to claim 1 further comprises: receiving, by the first wireless communication device, the position of automatic gain control (AGC) resources in the time domain unit for each of at least one resource pool or each resource pool of multiple resource pools, for each of at least one frequency domain resource, for each of at least one carrier, or for multiple carriers for carrier aggregation (CA).

5. The method according to claim 4, wherein, The AGC resources are defined by at least one of the following: AGC time domain resources before one SL PRS resource among multiple SL PRS resources, AGC time domain resources before resources for communicating a physical sidelink control channel (PSCCH), or a start time for SL positioning in the time domain resources.

6. The method according to claim 1, wherein, The SL PRS resource configuration includes: the configuration of time domain SL PRS resources in the time domain unit for each of at least one resource pool or each resource pool of multiple resource pools, for each of at least one frequency domain resource, for each of at least one carrier, or for multiple carriers for carrier aggregation (CA).

7. The method according to claim 1 further comprises: sending, by the first wireless communication device, sidelink control information (SCI) to multiple wireless communication devices to indicate the number of SLPRS reservations for transmissions with or without periodic reservation, where there is at least one of the following situations: In the time domain unit, the resources for transmitting the SCI and the SL PRS resources are mapped through a one-to-one mapping relationship; In the time domain unit, the resources for transmitting the SCI and multiple SL PRS resources are mapped through a one-to-many mapping relationship; and The second wireless communication device is one of the multiple wireless communication devices.

8. The method according to claim 7, wherein, The SCI only reserves the SL PRS resources belonging to the SL PRS resource packet, where the SL PRS resource packet includes one or more SL PRS resources mapped to the resources for transmitting the SCI.

9. The method according to claim 1 further comprises: The first wireless communication device sends sidelink control information (SCI) to one of the multiple wireless communication devices, and the SCI includes the number of sidelink physical layer reference signal (SL PRS) resource identifiers (IDs), where the number of SL PRS resource IDs is 1 less than the number of SL PRS reservations for transmissions that do not utilize periodic reservation.

10. The method according to claim 1 further comprises: The first wireless communication device sends sidelink control information (SCI) to one of the multiple wireless communication devices, and the SCI includes the number of sidelink physical layer reference signal (SL PRS) resource identifiers (IDs), where the number of SL PRS resource IDs is equal to the number of SL PRS reservations for transmissions that do not utilize periodic reservation.

11. The method according to claim 1 further comprises: The first wireless communication device sends sidelink control information (SCI) to one of the multiple wireless communication devices, and the SCI includes one or more lists of information, where the information includes at least one or more of the following: source ID, destination ID, resource reservation period, SL PRS priority, or broadcast type.

12. The method according to claim 1, wherein, For transmitting the SL PRS, the physical layer of the first wireless communication device determines at least one of the following: One or more SL PRS resources; Resources for transmitting sidelink control information (SCI); The number of time domain resources; The resource pool in which the one or more SL PRS resources will be transmitted; The priority of SL PRS transmission; The remaining packet delay budget; The resource reservation period; or A subset of resources for preemption and re-evaluation.

13. The method according to claim 1, wherein For transmitting the SL PRS, the higher layer of the first wireless communication device determines at least one of the following: One or more SL PRS resources; Resources for transmitting sidelink control information (SCI); The number of time domain resources; The resource pool in which the one or more SL PRS resources will be transmitted; The priority of SL PRS transmission; The remaining packet delay budget; The resource reservation period; or A subset of resources for preemption and re-evaluation, where the higher layer includes at least one of the following: Medium Access Control (MAC) layer, Radio Resource Control (RRC) layer, or Non-Access Stratum (NAS) layer.

14. According to the method of claim 1, wherein: The second wireless communication device receives the reservation of one or more first SL PRS resources from the first wireless communication device through the first sidelink control information (SCI) in the first time domain unit; The second wireless communication device receives a reservation of one or more SL PRS resources that are the same as the one or more first SL PRS resources from the first wireless communication device via a second SCI in a second time domain unit; The second wireless communication device determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is invalid.

15. The method according to claim 1, wherein: The second wireless communication device receives a reservation of one or more first SL PRS resources from the first wireless communication device via a first side link control information (SCI) in a first time domain unit; The second wireless communication device receives a reservation of one or more SL PRS resources that are different from the one or more first SL PRS resources from the first wireless communication device via a second SCI in a second time domain unit; The second wireless communication device determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is valid.

16. The method according to claim 1, wherein: The second wireless communication device receives a reservation of one or more first SL PRS resources from the first wireless communication device via a first side link control information (SCI) in a first time domain unit; The second wireless communication device receives a reservation of one or more second SL PRS resources from the first wireless communication device via a second SCI in a second time domain unit, wherein the first SCI and the second SCI are the same PSCCH resource; The second wireless communication device determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is invalid.

17. The method according to claim 1, wherein: The second wireless communication device receives a reservation of one or more first SL PRS resources from the first wireless communication device via a first side link control information (SCI) in a first time domain unit; The second wireless communication device receives a reservation of one or more second SL PRS resources from the first wireless communication device via a second SCI in a second time domain unit, wherein the first SCI and the second SCI are different PSCCH resources; The second wireless communication device determines that the reservation for the one or more first SL PRS resources indicated in the first SCI is valid.

18. The method according to any one of claims 14, 15, 16 or 17, wherein, The first SCI and the second SCI have at least one of the following: The same source ID; The same destination ID; The same broadcast type; The same resource reservation period; or The same SL PRS priority.

19. The method according to claim 1, further comprising at least one of the following: The first wireless communication device receives a user equipment (UE) information request from a device via the Long-Term Evolution Positioning Protocol (LPP) or the Side Link Positioning Protocol (SLPP); or The first wireless communication device transmits a UE information report to a device via the LPP or the SLPP.

20. The method according to claim 19, wherein, The UE information request or the UE information report includes at least one of the following: UE identifier (ID) for an anchor radio communication device, system frame number (SFN), direct frame number (DFN), SFN initial time, synchronization reference source, New Radio (NR) physical layer cell ID (PCI), NR cell global identifier (CGI), NR absolute radio frequency channel number (ARFCN), SL PRS configuration, geographical coordinates, geographical coordinates of the antenna reference point (ARP), UE type, UE transmission (Tx) timing error group (TEG) association, or UE Tx ARP association.

21. The method according to claim 19, wherein, The device includes a Location Management Function (LMF).

22. The method according to claim 19, wherein The device includes another radio communication device.

23. The method according to claim 19, further comprising: The device sends synchronization information between the plurality of radio communication devices and a reference radio communication device or between the plurality of radio communication devices and a reference network device based on the UE information reports of the plurality of radio communication devices, wherein the first radio communication device is one of the plurality of radio communication devices.

24. The method according to claim 23, wherein, The synchronization information includes at least one of the following: information of a reference UE, reference UE ID, reference timing of the reference UE, system frame number (SFN) of the reference UE, direct frame number (DFN) of the reference UE, Coordinated Universal Time (UTC) time, physical cell ID, global cell ID, absolute radio frequency channel number (ARFCN), quality of the timing of the reference UE, UE IDs of the plurality of radio communication devices, synchronization timing offset between the reference and one of the plurality of radio communication devices, and quality of the synchronization timing offset.

25. The method according to claim 1, wherein, The first radio communication device sends the SL PRS to the second radio communication device based on the SL PRS sequence identifier (ID).

26. The method according to claim 25, wherein the first radio communication device receives the SLPRS sequence ID from a higher layer by signaling, and the signaling includes at least one of the following: Long Term Evolution Positioning Protocol (LPP) from a Location Management Function (LMF); Sidelink Positioning Protocol (SLPP) from the LMF or a radio communication device; The higher layer of the first wireless communication device, wherein, The higher layer includes at least one of a Media Access Control (MAC) layer, a Radio Resource Control (RRC) layer, or a Non-Access Stratum (NAS) layer; Radio Resource Control (RRC) from a base station (BS); or The SL PRS resource configuration is pre-configured.

27. The method according to claim 25, wherein, The first radio communication device broadcasts the SL PRS sequence ID to a plurality of radio communication devices by at least one of sidelink control information (SCI) or Sidelink Positioning Protocol (SLPP).

28. The method according to claim 1, further comprising: The first radio communication device or the second radio communication device reports antenna reference point (ARP) position information to a device.

29. The method according to claim 28, wherein, The ARP position information includes a relative position of at least one ARP with respect to the position of the first radio communication device or the second radio communication device, and each ARP position is associated with an ARPID.

30. The method according to claim 28, wherein The device includes a Location Management Function (LMF) or another wireless communication device.

31. The method according to claim 1 further comprises: The first wireless communication device performs sensing and selects a first SL PRS resource, a first SL PRS resource bundle, or a first PSCCH resource in a first time domain unit to send the SL PRS to the second wireless communication device, where at least one of the following cases exists: The first SL PRS resource bundle includes one or more SL PRS resources associated with the PSCCH resource; The first wireless communication device determines a second SL PRS resource, a second resource bundle, or a second PSCCH resource in a second time domain unit to replace the first SL PRS resource, the first SL PRS resource bundle, or the first PSCCH resource in the first time domain unit after preemption or re-evaluation, where the second SL PRS resource, the second resource bundle, or the second PSCCH resource is respectively the same as the first SL PRS resource, the first SL PRS resource bundle, or the first PSCCH resource.

32. A wireless communication method, comprising: Receiving, by a first wireless communication device, downlink control information (DCI) from a network node, the DCI carrying information for scheduling a sidelink positioning reference signal (SL PRS); Sending, by the first wireless communication device, sidelink control information (SCI) and the SL PRS to a second wireless communication device based on the information included in the DCI.

33. The method according to claim 32, wherein, At least one of the following cases exists: The DCI is used to schedule the SL PRS transmission of the first wireless communication device in a dedicated resource pool or a shared resource pool; The same DCI format or the same Radio Network Temporary Identity (RNTI) is used for the DCI that schedules the SL PRS in the dedicated resource pool and the shared resource pool, where an indicator for indicating the resource pool type is indicated in the DCI; The DCI for scheduling the SL PRS in the dedicated resource pool and the DCI for scheduling the SL PRS in the shared resource pool have different DCI formats, or are accompanied by CRC scrambled by different RNTIs.

34. The method according to claim 32, wherein, The DCI or the SCI is used to indicate the transmission of the SL PRS of the first wireless communication device in the shared resource pool, and the DCI includes or applies at least one of the following: Different Radio Network Temporary Identities (RNTIs) for only scheduling the SL PRS transmission and for scheduling the SL PRS transmission and the SL data transmission; A field for indicating whether the DCI is for a dedicated resource pool or a shared resource pool; A field for indicating a time interval; A field for indicating frequency resource allocation; A field for indicating time resource allocation; A field for indicating whether the DCI is for only scheduling the SL PRS transmission or for scheduling the SL PRS transmission and the SL data transmission; A field for indicating one or more SL PRS resource IDs; A field for indicating a Hybrid Automatic Repeat reQuest (HARQ) process number to indicate the HARQ process number or both the HARQ process number and the SL PRS resource ID, wherein there is a (pre)-configured mapping relationship between the HARQ process number and the SL PRS resource; A field for indicating a Physical Uplink Control Channel (PUCCH) resource, wherein if only SL PRS transmission is scheduled, the wireless communication device sends only an acknowledgement (ACK) to the network node in the PUCCH; or A field for indicating a configuration index.

35. The method according to claim 32, wherein The DCI is used to indicate SL PRS transmission of the first wireless communication device in a dedicated resource pool, and the DCI includes or applies at least one of the following: A field for indicating whether the DCI is for a dedicated resource pool or a shared resource pool; A field for indicating a time interval; A field for indicating one or more SL PRS resource IDs; A field for indicating the SCI location of the first / initial SL PRS transmission; A field for indicating frequency resource allocation; A field for indicating time resource allocation; A field for indicating one or more Physical Sidelink Control Channel (PSCCH) resources; A field for indicating a Hybrid Automatic Repeat reQuest (HARQ) process number to indicate the HARQ process number or both the HARQ process number and the SL PRS resource ID, wherein there is a (pre)-configured mapping relationship between the HARQ process number and the SL PRS resource; A field for indicating a Hybrid Automatic Repeat reQuest (HARQ) process number to indicate the HARQ process number or both the HARQ process number and the PSCCH resource ID, wherein there is a (pre)-configured mapping relationship between the HARQ process number and the PSCCH resource; A field for indicating a configuration index.

36. A wireless communication method, comprising: The network node sends downlink control information (DCI) to a wireless communication device, and the DCI carries information for scheduling sidelink positioning reference signal (SL PRS).

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