System and method for transmitting and receiving positioning reference signal in NR unlicensed band

Abstract

Systems and methods for transmitting and receiving positioning reference signals in a new air interface (NR) unlicensed band are provided. The first wireless communication entity may transmit a positioning reference signal on the unlicensed band to the second wireless communication entity based on one or more channel occupancy parameters associated with the unlicensed band.

Description

Technical Field

[0001] The present disclosure relates to wireless communication, including but not limited to systems and methods for transmitting and receiving positioning reference signals in unlicensed bands of a New Radio (NR). Background Art

[0002] The standardization organization, the Third Generation Partnership Project (3GPP), is currently developing a new radio interface, called 5G New Radio (5G NR), and a next-generation packet core network (Next Generation Packet Core Network, NG-CN or NGC). 5G NR has three main components: a 5G access network (5G-AN), a 5G core network (5GC), and a user equipment (UE). To facilitate the implementation of different data services and requirements, the elements of the 5GC (also referred to as network functions) have been simplified, some of which are software-based and some are hardware-based, so that they can be adapted as needed. Summary of the Invention

[0003] Exemplary embodiments of the present disclosure are directed to solving problems related to one or more problems existing in the prior art, and providing additional features that will become apparent in conjunction with the detailed description with reference to the accompanying drawings. According to different embodiments, exemplary systems, methods, devices, and computer program products are disclosed. However, it should be understood that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art reading the present disclosure that various modifications can be made to the disclosed embodiments within the scope of the present disclosure.

[0004] At least one aspect relates to the following systems, methods, devices, or computer-readable media. A first wireless communication entity may transmit a positioning reference signal to a second wireless communication entity on an unlicensed band based on one or more channel occupancy parameters associated with the unlicensed band. The first wireless communication entity may identify the one or more channel occupancy parameters based on a Channel Access Priority Class (CAPC) table reused for data transmission.

[0005] In some embodiments, the first wireless communication entity may identify one or more channel occupancy parameters based on a preconfigured CAPC table. The configuration of the preconfigured CAPC table is associated with the configuration of the positioning reference signal. The one or more channel occupancy parameters may include at least one of the following: CAPC value, minimum contention window size, maximum contention window size, allowed contention window size, or maximum channel occupancy time (COT).

[0006] In some embodiments, the configuration of the positioning reference signal as DL-PRS may include at least one of the following: priority of the DL-PRS, transmission duration of the DL-PRS, repetition factor of the DL-PRS, time gap between two repetitions of the DL-PRS, or at least one item in the DL-PRS period. The configuration of the positioning reference signal as UL-SRS may include: priority of the UL-SRS, transmission duration of the UL-SRS, number of symbols of the UL-SRS, or UL-SRS period.

[0007] In some embodiments, the CAPC value may be indicated by an Information Element (IE). The CAPC value may be determined based on the configuration of the positioning reference signal. The CAPC value for transmitting the positioning reference signal as DL-PRS may be configured by a core network entity or a higher layer of the first wireless communication entity. The CAPC value for transmitting the positioning reference signal as UL-SRS may be configured by a core network entity or a higher layer of the first wireless communication entity or a higher layer of the second wireless communication entity.

[0008] In some embodiments, the CAPC value for transmitting the positioning reference signal as DL-PRS may be configured according to the Physical Frequency Layer (PFL), DL-PRS resource set, or DL-PRS resource. The CAPC value for transmitting the positioning reference signal as UL-SRS may be configured according to the Bandwidth Part (BWP), UL-SRS resource set, or UL-SRS resource, where the second wireless communication entity is in the RRC_CONNECTED state. The CAPC value for transmitting the positioning reference signal as UL-SRS may be configured according to the UL-SRS resource set or each UL-SRS resource, and where the second wireless communication entity is in the RRC_INACTIVE state.

[0009] In some embodiments, when at least one of the following conditions is met, the first wireless communication entity may use the Type 2A channel access procedure to initiate a channel occupancy procedure: (a) the transmission duration of the DL-PRS is at most 1 ms and the transmission duty cycle of the DL-PRS is at most 1 / 20; (b) the CAPC value configured for the DL-PRS is less than or equal to the CAPC threshold; (c) the priority value configured for the DL-PRS is less than the priority threshold; or (d) the DL-PRS is transmitted in broadcast mode. The first wireless communication entity may send a positioning reference signal in a shared channel occupancy procedure, provided that the following condition is met: the CAPC value configured for the positioning reference signal is less than or equal to the CAPC value for initiating the shared channel occupancy procedure.

[0010] In some embodiments, the period of the positioning reference signal may be associated with the period of the semi-static channel occupancy procedure. The association may include at least one of the following: the period of the positioning reference signal may be equal to the period of the semi-static channel occupancy procedure, or the period of the positioning reference signal may be an integer multiple of the period of the semi-static occupancy procedure. The configuration of the semi-static channel occupancy procedure for the positioning reference signal may not be limited to the number of radio frames. The configuration of the semi-static channel occupancy procedure may include: the period of the semi-static channel occupancy procedure, or the time offset of the period of the semi-static channel occupancy procedure relative to a reference time.

[0011] In some embodiments, the first wireless communication entity may report information about the semi-static channel occupancy procedure initiated by the first wireless communication entity to a core network entity. The information may include at least one of the following: the period of the semi-static channel occupancy procedure, the idle duration, or the COT length. The first wireless communication entity may receive a message including a recommendation of a transmission resource for a positioning reference signal that is a DL-PRS from the core network entity. The core network entity may recommend a transmission resource for a positioning reference signal that is a DL-PRS to the first wireless communication entity. The core network entity may recommend a transmission resource for a positioning reference signal that is a UL-SRS to the serving base station. The transmission resources for the positioning reference signal recommended to the first wireless communication entity and the transmission resources for the positioning reference signal recommended to the serving base station may be the same or different.

[0012] In some embodiments, in response to determining that the time domain resources configured for the positioning reference signal are within the COT, the first wireless communication entity may send the positioning reference signal. In response to determining that the time domain resources configured for the positioning reference signal are not within the COT, the first wireless communication entity may stop sending the positioning reference signal.

[0013] In some embodiments, if only the portion of symbols configured for positioning reference signals is within the COT, the first wireless communication entity may send positioning reference signals based on some rules. The first wireless communication entity may send channel occupancy window related information associated with the positioning reference signals to the third wireless communication entity. The first wireless communication entity or the second wireless communication entity may initiate the COT for the positioning reference signals in advance. If the COT is initiated based on the dynamic channel access procedure, the channel occupancy window related information may include at least one of the following: the CAPC value for initiating the COT, the duration of the COT, the start time of the COT, the length of the channel occupancy window, or the start time of the channel occupancy window.

[0014] In some embodiments, if the COT is initiated based on semi-static channel occupancy, the channel occupancy window related information may include at least one of the following: the semi-static channel occupancy period, the maximum COT of the semi-static channel occupancy period, the start time of the semi-static channel occupancy period, the length of the channel occupancy window, or the start time of the channel occupancy window. The length of the channel occupancy window may not be greater than the maximum COT. The length of the channel occupancy window may not be greater than the maximum COT of the semi-static channel occupancy period. The third wireless communication entity may be determined by the first wireless communication entity or the second wireless communication entity or the core network entity.

[0015] In some embodiments, the PFL configured for sending positioning reference signals may include an integer number of resource block (RB) sets. The first wireless communication entity may execute the channel access procedure for each RB set. A guard band may or may not be configured between two consecutive RB sets. An indicator of the multi-channel access procedure type may be included in the configuration of the PFL, or the configuration of the positioning service, or the configuration of the positioning reference signal resource set, or the configuration of the positioning reference signal resource.

[0016] In some embodiments, one or more transmission gaps for sending positioning reference signals as DL-PRS may be configured by the higher layer of the first wireless communication entity. One or more transmission gaps for sending positioning reference signals as UL-SRS may be configured by the core network entity, the higher layer of the first wireless communication entity, or the higher layer of the second wireless communication entity. Each of the one or more transmission gaps may be associated with a transmission gap ID. The configuration of the one or more transmission gaps may include at least one of the following: the transmission gap ID, the length of the one or more transmission gaps, the period of the one or more transmission gaps, the reference point in the time domain, or the offset of the one or more transmission gaps relative to the reference point in the time domain.

[0017] In some embodiments, the first wireless communication entity may perform a channel access procedure before transmitting on each positioning reference signal resource within a transmission gap. If the positioning reference signal is DL-PRS, the higher layer of the first wireless communication entity may configure multiple candidate COTs for transmitting the positioning reference signal within the transmission gap. If the positioning reference signal is UL-SRS, the core network entity, or the higher layer of the first wireless communication entity, or the higher layer of the serving base station may configure multiple candidate COTs for transmitting the positioning reference signal within the transmission gap. The configuration of the transmission gap may also include the number of candidate COTs and the configuration of the candidate COTs. The candidate COTs within the transmission gap may be periodic or aperiodic. If the candidate COT is periodic, the configuration of one of the candidate COTs includes at least one of the following: candidate COT ID, candidate COT length, candidate COT period, or the offset of the candidate COT relative to the start time of the transmission gap. If the candidate COT is aperiodic, the configuration of one of the candidate COTs includes at least one of the following: candidate COT ID, candidate COT length, or the offset of the candidate COT relative to the start time of the transmission gap. The candidate COTs for transmitting the positioning reference signal as DL-PRS within the transmission gap may be configured by transmission gap, or PFL, or serving cell or UE. The candidate COTs for transmitting the positioning reference signal as UL-SRS within the transmission gap may be configured by transmission gap, or UE or TRP.

[0018] In some embodiments, the first wireless communication entity may perform a channel access procedure for each candidate COT. The configuration of the transmission gap may also include the maximum number of candidate COTs initiated using the Type 1 channel access procedure. The total duration of all candidate COTs initiated using the Type 1 channel access procedure shall not be greater than the length of the transmission gap. The configuration of the transmission gap also includes the repetition information of the transmission gap. The repetition information of the transmission gap may include at least one of the following: the repetition factor of the transmission gap or the time gap between two repetitions.

[0019] In some embodiments, the first wireless communication entity may transmit the positioning reference signal on multiple successfully accessed channels, provided that the following conditions are met: the channels are consecutive and the number of consecutive channels is not less than a threshold. The first wireless communication entity may transmit the positioning reference signal according to a channel pattern, provided that the following conditions are met: the successfully accessed channels correspond to the channel pattern. The channel pattern may be configured by the core network entity. The second wireless communication entity may receive the positioning reference signal according to the channel pattern.

[0020] In some embodiments, the transmission of the positioning reference signal and the transmission of another positioning reference signal sent by another first wireless communication entity are configured based on a comb - based multiplexing manner. The first wireless communication entity sends access channel information and the configuration of the positioning reference signal to a third wireless communication entity. The access channel information may include at least one of the following: the ID of the set of RBs accessed, the starting position of the set of RBs accessed in the frequency domain, or the bandwidth of each set of RBs accessed. The configuration of the positioning reference signal may include at least one of the following: the comb size of the positioning reference signal; or the comb offset of the positioning reference signal.

[0021] In some embodiments, one or more channel occupancy parameters are sent by a first or second communication entity to a core network entity. The one or more channel occupancy parameters may include at least one of the following: COT ID, COT length, COT start time, the ID of the set of RBs occupied by the positioning reference signal within the COT; the starting position of the set of RBs within the COT in the frequency domain; or the bandwidth of each set of RBs within the COT.

[0022] In some embodiments, the second communication entity receives the positioning reference signal as a DL - PRS according to a reception configuration configured by a higher layer of the first communication entity or a core network entity. The reception configuration includes a first search space set group and a second search space set group corresponding to the COT. The first search space set group is configured to detect DCI outside the COT. The second search space set group is configured to receive the DL - PRS within the COT. The second search space set group is associated with the period of the positioning reference signal resource.

[0023] In some embodiments, the reception configuration includes a search window, where the search window is periodic or aperiodic. If the search window is periodic, the configuration of the search window includes at least one of the following: the length of the search window, the period of the search window, or the start time of the first period of the search window. If the search window is aperiodic, the configuration of the search window may include at least one of the following: the length of the search window, or the period of the search window. The reception configuration may include a search space set group corresponding to the search window. The search space set group may be configured to receive the DL - PRS within the search window. The second communication entity may continuously receive the positioning reference signal as a DL - PRS within the search window. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The various exemplary embodiments of the present disclosure are described in detail below with reference to the following figures or drawings. The drawings are provided for illustrative purposes only, and the drawings only depict the exemplary embodiments of the present disclosure to facilitate the reader's understanding of the present disclosure. Therefore, the drawings should not be regarded as limiting the breadth, scope, or applicability of the present disclosure. It should be noted that for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

[0025] Figure 1 Illustrates an exemplary cellular communication network that can implement the technology of the present disclosure;

[0026] Figure 2 Shows a block diagram of an exemplary base station and user equipment according to some embodiments of the present disclosure;

[0027] Figure 3 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0028] Figure 4 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0029] Figure 5 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0030] Figure 6 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0031] Figure 7 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0032] Figure 8 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0033] Figure 9 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0034] Figure 10 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0035] Figure 11 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0036] Figure 12 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0037] Figure 13 Shows an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0038] Figure 14Illustrates an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0039] Figure 15 Illustrates an exemplary configuration for transmitting and receiving positioning reference signals according to some embodiments of the present disclosure;

[0040] Figure 16 Illustrates a flowchart of an exemplary method for transmitting and receiving positioning reference signals according to an embodiment of the present disclosure. Detailed Embodiments

[0041] 1. Mobile communication technology and environment

[0042] Figure 1 Illustrates an exemplary wireless communication network and / or system 100 that can implement the technology of the present disclosure according to an embodiment of the present disclosure. In the following discussion, the wireless communication network 100 can be any wireless network, such as a cellular network or a Narrowband Internet of Things (NB-IoT) network, and is referred to as "network 100" in the present disclosure. Such an exemplary network 100 includes base stations 102 (hereinafter "BS102"; also referred to as wireless communication nodes) and user equipment 104 (hereinafter "UE104"; also referred to as wireless communication devices) that can communicate with each other via communication links 110 (e.g., wireless communication channels), and cell groups 126, 130, 132, 134, 136, 138, and 140 that cover a geographical area 101. In Figure 1 BS102 and UE 104 are included within the respective geographical boundaries of cell 126. Each of the other cells 130, 132, 134, 136, 138, and 140 may include at least one base station operating under its allocated bandwidth to provide sufficient radio coverage to its intended users.

[0043] For example, BS102 may operate under an allocated channel transmission bandwidth to provide sufficient coverage to UE104. BS102 and UE104 may communicate via a downlink radio frame 118 and an uplink radio frame 124, respectively. Each radio frame 118 / 124 may be further divided into subframes 120 / 127, and these subframes may include data symbols 122 / 128. In the present disclosure, BS102 and UE104 are described as non-limiting examples of "communication nodes", and generally, they can implement the methods of the present disclosure. According to various embodiments of the present disclosure, such communication nodes are capable of wireless and / or wired communication.

[0044] Figure 2FIG. 0 shows a block diagram of an exemplary wireless communication system 200 for transmitting and receiving wireless communication signals (e.g., OFDM / OFDMA signals) in accordance with some embodiments of the present disclosure. System 200 may include components and elements configured to support known or conventional operating features not detailed in the present disclosure. In one exemplary embodiment, system 200 may be used to transmit (e.g., send and receive) data symbols in a wireless communication environment such as Figure 1 the wireless communication environment 100).

[0045] System 200 generally includes a base station 202 (referred to as "BS202" in the following description) and a user equipment 204 (referred to as "UE 204" in the following description). BS202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each coupled and interconnected with each other via a data communication bus 220 as needed. UE204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each coupled and interconnected with each other via a data communication bus 240 as needed. BS202 communicates with UE204 via a communication channel 250, which may be any wireless channel or other medium suitable for data transmission as described in the present disclosure.

[0046] As will be understood by those of ordinary skill in the art, system 200 may also include any number of modules other than Figure 2 those shown. Those skilled in the art will understand that the different exemplary blocks, modules, circuits, and processing logics described in connection with the embodiments of the present disclosure may be implemented in hardware, computer-readable software, firmware, or any practical combination thereof. To clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, different exemplary components, blocks, modules, circuits, and steps are generally described in terms of their functional aspects. Whether the functions are implemented as hardware, firmware, or software may depend on the particular application and the design constraints imposed on the overall system. Persons familiar with the concepts described in the present disclosure may implement such functions in a suitable manner for each particular application, but such implementation decisions should not be construed as limiting the scope of the present disclosure.

[0047] According to some embodiments, the UE transceiver 230 may be referred to in this disclosure as an "uplink" transceiver 230, which includes a Radio Frequency (RF) transmitter and an RF receiver, and each RF transmitter and RF receiver includes circuitry coupled to an antenna 232. Alternatively, a duplex switch (not shown) may couple the uplink transmitter or receiver to the uplink antenna in a time-division duplex manner. Similarly, according to some embodiments, the BS transceiver 210 may be referred to in this disclosure as a "downlink" transceiver 210, which includes an RF transmitter and an RF receiver, and each RF transmitter and RF receiver includes circuitry coupled to an antenna 212. Alternatively, a downlink duplex switch may couple the downlink transmitter or receiver to the downlink antenna 212 in a time-division duplex manner. The operations of the two transceiver modules 210 and 230 may be coordinated in time such that the uplink receiver circuitry is coupled to the uplink antenna 232 to receive transmissions via the wireless transmission link 250, while the downlink transmitter is coupled to the downlink antenna 212. Conversely, the operations of the two transceivers 210 and 230 may be coordinated in time such that the downlink receiver is coupled to the downlink antenna 212 to receive transmissions via the wireless transmission link 250, while the uplink transmitter is coupled to the uplink antenna 232. In some embodiments, there is tight time synchronization with a minimum guard time between changes in the duplex direction.

[0048] The UE transceiver 230 and the base station transceiver 210 are configured to communicate via a wireless data communication link 250 and cooperate with a suitably configured RF antenna arrangement 212 / 232 that can support a particular wireless communication protocol and modulation scheme. In some exemplary embodiments, the UE transceiver 210 and the base station transceiver 210 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G standards, etc. However, it should be understood that this disclosure need not be limited to the application of specific standards and associated protocols. Instead, the UE transceiver 230 and the base station transceiver 210 may be configured to support alternative or additional wireless data communication protocols, including future standards or their variants.

[0049] According to different embodiments, BS202 can be, for example, an evolved node B (eNB), serving eNB, target eNB, femtocell, or picocell. In some embodiments, UE 204 can be embodied as different types of user equipment, such as a mobile phone, smartphone, personal digital assistant (PDA), tablet computer, laptop computer, wearable computing device, etc. Processor modules 214 and 236 can be implemented or realized using a general-purpose processor, content addressable memory, digital signal processor, application specific integrated circuit, 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 in this disclosure. In this way, the processor can be implemented as a microprocessor, controller, microcontroller, state machine, etc. The processor can also be implemented as a combination of computing devices, for example, a combination of a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors combined with a digital signal processor core, or any other such configuration.

[0050] In addition, the steps of the methods or algorithms described in connection with the embodiments of this disclosure can be directly embodied in hardware, firmware, software modules executed by processor modules 214 and 236 respectively, or any actual combination thereof. Memory modules 216 and 234 can be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. In this regard, memory modules 216 and 234 can be respectively coupled to processor modules 210 and 230 such that processor modules 210 and 230 can respectively read information from and write information to memory modules 216 and 234. Memory modules 216 and 234 can also be integrated into their respective processor modules 210 and 230. In some embodiments, memory modules 216 and 234 can each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions to be executed by processor modules 210 and 230 respectively. Memory modules 216 and 234 can also each include non-volatile memory for storing the instructions executed by processor modules 210 and 230 respectively.

[0051] The network communication module 218 generally represents the hardware, software, firmware, processing logic, and / or other components of the base station 202 for enabling two-way communication between the base station transceiver 210 and other network components, as well as communication nodes configured to communicate with the base station 202. For example, the network communication module 218 may be configured to support Internet or WiMAX traffic. In a typical deployment, the network communication module 218 provides an 802.3 Ethernet interface (but is not limited to this) so that the base station transceiver 210 can communicate with a traditional computer network based on Ethernet. In this way, the network communication module 218 may include a physical interface for connecting to a computer network (e.g., a Mobile Switching Center (MSC)). As used in this disclosure, the terms "configured to", "configured for", and variations thereof for a particular operation or function refer to a device, component, circuit, structure, machine, signal, etc. that is physically constructed, programmed, formatted, and / or arranged to perform the particular operation or function.

[0052] The Open Systems Interconnection (OSI) model (referred to as the "Open Systems Interconnection model" in this disclosure) defines the conceptual and logical layout of network communication used by systems (e.g., wireless communication devices, wireless communication nodes) that are open to interconnecting and communicating with other systems. The model is divided into seven sub-components or layers, each of which represents a collection of concepts that provide services to the upper and lower layers. The OSI model also defines a logical network and effectively describes computer packet transfer using different layer protocols. The OSI model may also be referred to as the seven-layer OSI model or the seven-layer model. In some embodiments, the first layer may be the physical layer. In some embodiments, the second layer may be the Medium Access Control (MAC) layer. In some embodiments, the third layer may be the Radio Link Control (RLC) layer. In some embodiments, the fourth layer may be the Packet Data Convergence Protocol (PDCP) layer. In some embodiments, the fifth layer may be the Radio Resource Control (RRC) layer. In some embodiments, the sixth layer may be the Non Access Stratum (NAS) layer or the Internet Protocol (IP) layer, and the seventh layer is other layers.

[0053] Various exemplary embodiments of the present disclosure will be described below with reference to the accompanying drawings so that those of ordinary skill in the art can make and use the present disclosure. It will be apparent to those of ordinary skill in the art that, after reading the present disclosure, various changes or modifications can be made to the examples described herein without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific step order or hierarchical structure of the methods of the present disclosure is merely an example method. Based on design preferences, the specific step order or hierarchical structure of the disclosed method or process can be rearranged while still falling within the scope of the present disclosure. Thus, those of ordinary skill in the art will understand that the methods and techniques of the present disclosure present different steps or actions in a sample order, and the present disclosure is not limited to the specific order or hierarchical structure presented, unless expressly stated otherwise.

[0054] 2. Systems and methods for transmitting and receiving positioning reference signals in the New Radio (NR) unlicensed band

[0055] In the Frequency Range 1 (FR1) of the NR system, there are both licensed bands and unlicensed bands. The licensed bands support data transmission and positioning services, while the unlicensed bands have idle spectrum available for signal transmission. However, in NR in the unlicensed band (NR-U), only data transmission and reception are supported, and positioning services may not be available. The present disclosure focuses on the challenges of transmitting and receiving the Downlink Positioning Reference Signal (DL-PRS) and the Uplink Sounding Reference Signal (ULSRS) for positioning in the unlicensed band. Different solutions are provided for solving the transmission and reception of DL-PRS and UL SRS for positioning in NR-U.

[0056] In NR-U, the transmission and reception of DL / UL data can be supported. For DL positioning, the gNB can transmit DL-PRS to the UE via the Uu interface, and the UE can measure the DL-PRS to obtain positioning measurements. For UL positioning, the UE can transmit ULSRS for positioning via the Uu interface, and the gNB can measure the SRS to obtain positioning measurements. However, the current NR system only supports positioning services in the licensed bands of FR1, which poses a problem for transmitting and receiving DL-PRS and ULSRS for positioning in the unlicensed bands of FR1.

[0057] Embodiment 1: Configuration of CAPC for DL-PRS / Positioning SRS.

[0058] In an unlicensed band, a gNB / UE performing transmission on a channel may execute a channel access procedure for accessing the channel on which the transmission is performed. A channel access procedure for data transmission in NR-U may be a Type 1 channel access procedure. In the Type 1 channel access procedure, the sensing duration may be random, which is related to the Channel Access Priority Class (CAPC). There are four CAPCs for DL and UL respectively. Each CAPC may correspond to an allowed contention window size and a maximum Channel Occupancy Time (COT). Tables 1 and 2 respectively show the associations between the CAPCs for DL and UL, the allowed contention sizes, and the maximum COT. The gNB / UE may use any CAPC for DL / UL transmission to execute the Type 1 channel access procedure. After the gNB / UE successfully accesses the channel based on the Type 1 channel access procedure using a CAPC, the DL / UL transmission time cannot exceed the maximum COT associated with the CAPC. However, how to access the channel for transmitting DL-PRS / UL SRS for positioning is a problem. A solution for accessing the channel for transmitting DL-PRS / UL SRS for positioning is based on the Type 1 channel access procedure. In this embodiment, the CAPC for DL-PRS / UL SRS for positioning is designed and configured.

[0059]

[0060] Table 1 CAPCs for DL

[0061]

[0062] Table 2 CAPCs for UL

[0063] For the DL-PRS CAPC table, there are two alternatives:

[0064] (1) The CAPC table for DL data transmission may be reused. That is, the associations between the CAPC, the contention window size, and the maximum COT continue to follow the same associations as when used for DL data transmission, as shown in Table 1.

[0065] (2) A specific CAPC table that can be pre-configured for DL-PRS. The parameters of the DL-PRS CAPC table can be related to the configuration of DL-PRS. The parameters of the DL-PRS CAPC table can at least include the minimum contention window size, the maximum contention window size, the allowed contention window size, and the maximum COT. The configuration of DL-PRS can include one or more of the following: the priority of DL-PRS, the duration of DL-PRS transmission, the repetition factor of DL-PRS, the time gap between two repetitions of DL-PRS, and the DL-PRS period.

[0066] ■ The maximum COT of the DL-PRS CAPC table is related to the duration of DL-PRS transmission. The duration of DL-PRS transmission depends on the repetition factor of DL-PRS, the time gap between two repetitions of DL-PRS, and the DL-PRS period.

[0067] ■ The minimum contention window size, the maximum contention window size, and the allowed contention window size of the DL-PRS CAPC table are related to the DL-PRS priority.

[0068] ■ The DL-PRS CAPC value of the DL-PRS CAPC table is related to the DL-PRS priority. A mapping can be established between the DL-PRS CAPC value and the DL-PRS priority.

[0069] For DL-PRS transmission, the CAPC can be configured by the Location Management Function (LMF) and transmitted to the gNB by the LMF via the NR Positioning Protocol A (NRPPa). Alternatively, the CAPC for DL-PRS transmission can be determined by the higher layer of the gNB (e.g., RRC / MAC CE).

[0070] The CAPC for DL-PRS transmission can be configured / determined according to the Physical Frequency Layer (PFL). Alternatively, the CAPC for DL-PRS transmission can be configured / determined according to the DL-PRS resource set. Alternatively, the CAPC for DL-PRS transmission can be configured / determined according to the DL-PRS resource.

[0071] There are two alternatives for the configuration / determination of the CAPC for DL-PRS transmission:

[0072] (1) The CAPC for DL-PRS transmission can be indicated by an IE (Information Element).

[0073] (2) The configuration / determination of the DL-PRS CAPC may be associated with the configuration of the DL-PRS. The configuration of the DL-PRS includes one or more of the following: the priority of the DL-PRS, the duration of the DL-PRS transmission, the repetition factor of the DL-PRS, the time gap between two repetitions of the DL-PRS, and the DL-PRS period. The association between the DL-PRS CAPC and the configuration of the DL-PRS may include:

[0074] ■ The maximum COT corresponding to the CAPC may be associated with the duration of the DL-PRS transmission, where the duration of the DL-PRS transmission depends on one or more of the repetition factor of the DL-PRS, the time gap between two repetitions of the DL-PRS, and the DL-PRS period. That is, there is a mapping relationship between the maximum COT and the duration of the DL-PRS transmission.

[0075] If the duration of the DL-PRS transmission is obtained, the maximum COT may be obtained based on this association.

[0076] Then, the CAPC for the DL-PRS transmission may be obtained according to the maximum COT corresponding in the DL-PRS CAPC table.

[0077] transmission.

[0078] ■ The minimum contention window size, the maximum contention window size, and the allowed contention window size corresponding to the CAPC may be associated with the DL-PRS priority. That is, there is a mapping relationship between the allowed contention window size and the DL-PRS priority. If the DL-PRS priority is known, the allowed contention window size may be obtained. Then, according to the allowed contention window size corresponding in the DL-PRS CAPC table, the CAPC for the DL-PRS transmission may be obtained.

[0079] ■ The CAPC value for the DL-PRS transmission may be associated with the DL-PRS priority. That is, there is a mapping relationship between the DL-PRS CAPC value and the DL-PRS priority. If the DL-PRS priority is known, the CAPC value for the DL-PRS transmission may be obtained.

[0080] For the CAPC table of the UL SRS transmission for positioning, there are two alternatives:

[0081] (1) The CAPC table for UL data transmission may be reused. That is, the association between the CAPC, the contention window size, and the maximum COT continues to follow this association when used for UL data transmission, as shown in Table 2.

[0082] (2) A specific CAPC table that can be pre-configured for UL positioning SRS. The parameters of the UL positioning SRS CAPC table are related to the configuration of the UL SRS. The parameters of the UL positioning SRS CAPC table include at least the minimum contention window size, the maximum contention window size, the allowed contention window size, and the maximum COT. The configuration of the UL positioning SRS can include one or more of the following: the priority of the positioning SRS, the duration of the positioning SRS transmission, the number of symbols of the positioning SRS, and the positioning SRS period.

[0083] ■ The maximum COT of the positioning SRS CAPC table is related to the duration of the positioning SRS transmission. The duration of the positioning SRS transmission depends on the number of symbols of the positioning SRS and the positioning SRS period.

[0084] ■ The minimum contention window size, the maximum contention window size, and the allowed contention window size of the positioning SRS CAPC table are related to the positioning SRS priority.

[0085] ■ The positioning SRS CAPC value of the positioning SRS CAPC table is related to the positioning SRS priority. A mapping can be established between the positioning SRS CAPC value and the positioning SRS priority.

[0086] For positioning SRS transmission, the CAPC can be configured by the Location Management Function (LMF) and transmitted to the UE by the LMF via the LTE Positioning Protocol (LPP). Alternatively, the CAPC for positioning SRS transmission can be configured / determined by the higher layer of the gNB / UE (e.g., RRC / MACCE).

[0087] In the RRC_CONNECTED mode, the CAPC for positioning SRS transmission can be configured / determined according to the Bandwidth Part (BWP). Alternatively, in the RRC_CONNECTED mode, the CAPC for positioning SRS transmission can be configured / determined according to the positioning SRS resource set. Alternatively, in the RRC_CONNECTED mode, the CAPC for positioning SRS transmission can be configured / determined according to the positioning SRS resource.

[0088] In the RRC_INACTIVE mode, the CAPC for positioning SRS transmission can be configured / determined according to the positioning SRS resource set. Alternatively, in the RRC_INACTIVE mode, the CAPC for positioning SRS transmission can be configured / determined according to the positioning SRS resource.

[0089] For the configuration / determination of the CAPC for positioning SRS transmission, there are two alternatives:

[0090] (1) The CAPC for positioning SRS transmission can be indicated by an IE (Information Element).

[0091] (2) Configure the positioning SRS CAPC / Determine the association that can be related to the configuration of the positioning SRS. The configuration of the positioning SRS may include one or more of the following: the priority of the positioning SRS, the duration of the positioning SRS transmission, the number of symbols of the positioning SRS, or the positioning SRS period. The association between the positioning SRS CAPC and the configuration of the positioning SRS includes one or more of the following:

[0092] ■ The maximum COT corresponding to the CAPC may be associated with the duration of the positioning SRS transmission, where the duration of the positioning SRS transmission depends on the number of symbols of the positioning SRS and the positioning SRS period. That is, there is a mapping between the maximum COT and the duration of the positioning SRS transmission. If the duration of the positioning SRS transmission is obtained, the maximum COT can be obtained based on this association. Then, the CAPC for the positioning SRS transmission can be obtained according to the maximum COT corresponding in the positioning SRS CAPC table.

[0093] ■ The minimum contention window size, the maximum contention window size, and the allowed contention window size corresponding to the CAPC may be associated with the positioning SRS priority. That is, there is a mapping relationship between the allowed contention window size and the positioning SRS priority. If the positioning SRS priority is known, the allowed contention window size can be obtained. Then, according to the allowed contention window size corresponding in the positioning SRS CAPC table, the CAPC for the positioning SRS transmission can be obtained.

[0094] ■ The CAPC value for the positioning SRS transmission may be associated with the positioning SRS priority. That is, there is a mapping relationship between the positioning SRS CAPC value and the positioning SRS priority. If the positioning SRS priority is known, the CAPC value for the positioning SRS transmission can be obtained.

[0095] Embodiment 2: DL-PRS / Positioning SRS transmission based on the Type 2 channel access procedure.

[0096] For the current NR-U DL / UL data transmission, another channel access procedure is the Type 2 channel access procedure, where the sensing duration is fixed. The Type 2 channel access procedure is subdivided into three types of channel access procedures, which are Type 2A, Type 2B, and Type 2C. Another solution for accessing the channel for positioning DL-PRS / UL SRS is based on the Type 2 channel access procedure.

[0097] If the DL-PRS transmission duration is at most 1 ms, and the DL-PRS transmission duty cycle is at most 1 / 20, and additionally, if one or more of the following conditions are satisfied, the gNB may initiate DL channel occupancy for DL-PRS transmission using the Type 2A channel occupancy procedure:

[0098] ■ The CAPC value of the DL-PRS is less than or equal to the CAPC threshold.

[0099] ○ The CAPC threshold may be pre-configured.

[0100] ○ Alternatively, the CAPC threshold may be determined by a higher layer of the gNB (e.g., RRC, MAC CE).

[0101] ○ Alternatively, the CAPC threshold may also be configured by the LMF and transmitted to the gNB via NRPPa.

[0102] ■ The priority value of the DL-PRS is less than the priority threshold.

[0103] ○ The priority threshold may be pre-configured.

[0104] ○ Alternatively, the priority threshold may be determined by a higher layer of the gNB (e.g., RRC, MAC CE).

[0105] ○ Alternatively, the priority threshold may also be configured by the LMF and transmitted to the gNB via NRPPa.

[0106] ■ The DL-PRS transmission is broadcast to multiple UEs.

[0107] If the UE initiates a COT for UL transmission and shares the COT with the gNB for DL transmission, and if the CAPC value of the DL-PRS is less than or equal to the CAPC value used to initiate the shared COT, the gNB may transmit the DL-PRS in the shared COT using the Type 2 channel access procedure after the UL transmission. If the gNB initiates a COT for DL transmission and shares the COT with the UE for UL transmission, and if the CAPC value of the UL positioning SRS is less than or equal to the CAPC value used to initiate the shared COT, the UE may transmit the UL positioning SRS in the shared COT using the Type 2 channel access procedure after the DL transmission. If the gNB initiates a COT for DL transmission and shares the COT with the UE for UL transmission, and if any gap between any two transmissions in the shared COT is at most 25 microseconds, it may transmit the DL-PRS using the Type 2 channel access procedure after the UL transmission.

[0108] Example 3: Channel access for DL-PRS transmission after / before DL data transmission.

[0109] For DL data transmission and DL-PRS transmission, there can be two cases: the DL-PRS transmission is after the DL data transmission, and the DL-PRS transmission is before the DL data transmission. In this case, it is necessary to consider how to access the channel for DL-PRS transmission and DL data transmission. In this embodiment, some solutions are provided for channel access to transmit DL-PRS after / before DL data.

[0110] Consider the case where DL data transmission occurs without a time gap after DL-PRS transmission. The DL-PRS transmission may not end at the start of DL data transmission. Figure 3 A schematic diagram of DL-PRS transmission before DL data transmission is shown. If the gNB expects to use the Type 1 channel access procedure and the corresponding DL-PRS CAPC to transmit the DL-PRS transmission, and the gNB expects to use the Type 1 channel access procedure and the corresponding CAPC to transmit the DL data, it can be achieved in the following ways:

[0111] ■ The gNB can use the DL-PRS CAPC value to initiate channel occupancy and transmit the DL-PRS transmission. If the DL-PRS CPAC value corresponding to the DL-PRS transmission is greater than or equal to the CAPC value corresponding to the DL data transmission, the gNB can directly continue to transmit the DL data without a gap from the start of the DL data transmission. The total transmission duration of the DL-PRS transmission and the DL data transmission cannot exceed the maximum COT corresponding to the DL-PRS CAPC value.

[0112] ○ Otherwise, the gNB can terminate the DL-PRS transmission by discarding the transmission on the symbols of at least the last DL-PRS transmission before the DL data transmission, and attempt to initiate channel occupancy using the CAPC value corresponding to the DL data transmission for DL data transmission.

[0113] ○ Otherwise, or, the gNB can fully transmit the DL-PRS transmission and ignore the DL data transmission.

[0114] ■ Alternatively, the gNB may determine a unified CAPC value to initiate channel occupancy for DL-PRS transmission and DL data transmission. The unified CAPC value is related to the DL-PRS transmission duration and the DL data transmission duration. The maximum COT corresponding to the unified CAPC value may be greater than or equal to the total transmission duration of the DL-PRS transmission and the DL data transmission. The unified CAPC value may be used to initiate channel occupancy at the start of the DL-PRS transmission, and the DL-PRS transmission may be performed. If the DL-PRS transmission has not ended before the start of the DL data transmission, and if the DL-PRS CPAC value corresponding to the DL-PRS transmission is greater than or equal to the CAPC value corresponding to the DL data transmission, the gNB may directly continue to transmit the DL data without a gap from the start of the DL data transmission.

[0115] ○ If the DL-PRS transmission has not ended before the start of the DL data transmission, and if the DL-PRS CPAC value corresponding to the DL-PRS transmission is less than the CAPC value corresponding to the DL data transmission, the gNB may terminate the DL-PRS transmission by discarding the transmission on the symbols of at least the last DL-PRS transmission before the DL data transmission, and attempt to initiate channel occupancy using the CAPC value corresponding to the DL data transmission for the DL data transmission.

[0116] ○ Alternatively, if the DL-PRS transmission has not ended before the start of the DL data transmission, and if the DL-PRS CPAC value corresponding to the DL-PRS transmission is less than the CAPC value corresponding to the DL data transmission, the gNB may completely transmit the DL-PRS transmission and ignore the DL data transmission.

[0117] ■ Alternatively, if the DL-PRS CPAC value corresponding to the DL-PRS transmission is greater than the CAPC value corresponding to the DL data transmission, the gNB may use the CAPC value corresponding to the DL data transmission to transmit the DL data transmission and ignore the DL-PRS transmission. If the DL-PRS CPAC value corresponding to the DL-PRS transmission is less than the CAPC value corresponding to the DL data transmission, the gNB may use the DL-PRS CAPC value corresponding to the DL-PRS transmission to transmit the DL-PRS transmission and ignore the DL data transmission. If the DL-PRS CPAC value corresponding to the DL-PRS transmission is equal to the CAPC value corresponding to the DL data transmission, the gNB may initiate channel occupancy using the DL-PRS CAPC value and transmit the DL-PRS transmission, and then directly continue to transmit the DL data without a gap from the start of the DL data transmission.

[0118] Figure 3 A schematic diagram of gapless DL data transmission after DL-PRS transmission is provided.

[0119] Consider the case where DL-PRS transmission is performed without a time gap after DL data transmission. At the start of DL-PRS transmission, the DL data transmission may not have ended. Figure 4 A schematic diagram of DL-PRS transmission after DL data transmission is shown. If the gNB expects to use the Type 1 channel access procedure and the corresponding DL-PRS CAPC to transmit DL-PRS, and the gNB expects to use the Type 1 channel access procedure and the corresponding CAPC to transmit DL data, it can be achieved in the following ways:

[0120] ■ The gNB can initiate channel occupancy using the CAPC value corresponding to the DL data transmission and transmit the DL data completely. If the CPAC value corresponding to the DL data transmission is greater than or equal to the DL-PRS CAPC value corresponding to the DL-PRS transmission, by discarding the DL-PRS transmission on the symbols of the DL-PRS transmission time that conflicts with the DL data transmission, the gNB can directly continue to transmit the DL-PRS without a gap from the end of the DL data transmission. The total transmission duration of the DL data transmission and the DL-PRS transmission cannot exceed the maximum COT corresponding to the CAPC value of the DL data transmission. Otherwise, the gNB can ignore the DL-PRS transmission.

[0121] ■ Alternatively, the gNB can determine a unified CAPC value to initiate channel occupancy for DL data transmission and DL-PRS transmission. The unified CAPC value is related to the DL data transmission duration and the DL-PRS transmission duration. The maximum COT corresponding to the unified CAPC value can be greater than or equal to the total transmission duration of the DL data transmission and the DL-PRS transmission. Channel occupancy is initiated using the unified CAPC value at the start of the DL data transmission, and the DL data transmission can be transmitted completely. If the DL data transmission has not ended before the start of the DL-PRS transmission, and if the CPAC value corresponding to the DL data transmission is greater than or equal to the DL-PRS CAPC value corresponding to the DL-PRS transmission, by discarding the DL-PRS transmission on the symbols of the DL-PRS transmission time that conflicts with the DL data transmission, the gNB can directly continue to transmit the DL-PRS transmission without a gap from the end of the DL data transmission. If the DL data transmission has not ended before the start of the DL-PRS transmission, and if the CPAC value corresponding to the DL data transmission is less than the DL-PRS CAPC value corresponding to the DL-PRS transmission, the gNB ignores the DL-PRS transmission.

[0122] ■ Alternatively, if the CPAC value corresponding to the DL data transmission is greater than the DL-PRS CAPC value corresponding to the DL-PRS transmission, the gNB may use the DL-PRS CAPC value corresponding to the DL-PRS transmission to transmit the DL-PRS and ignore the DL data transmission. If the CPAC value corresponding to the DL data transmission is less than the DL-PRS CAPC value corresponding to the DL-PRS transmission, the gNB may use the CAPC value corresponding to the DL data transmission to transmit the DL data and ignore the DL-PRS transmission. If the CPAC value corresponding to the DL data transmission is equal to the DL-PRS CAPC value corresponding to the DL-PRS transmission, the gNB may initiate channel occupancy using the CAPC value corresponding to the DL data transmission, fully transmit the DL data transmission, and then the gNB may continue to transmit the DL-PRS transmission without a gap directly from the end of the DL data transmission by discarding the DL-PRS transmission on the symbols of the DL-PRS transmission time that conflict with the DL data transmission.

[0123] Figure 4 A schematic diagram of transmitting the DL-PRS transmission without a gap after the DL data transmission is provided.

[0124] Consider the case of transmitting the DL data transmission with a time gap after or before the DL-PRS transmission. That is, the DL-PRS transmission is fully transmitted before the start of the DL data, or the DL data is fully transmitted before the start of the DL-PRS transmission. Figure 5 A schematic diagram of transmitting the DL-PRS transmission after / before the DL data transmission is shown. If the gNB expects to transmit the DL-PRS transmission using the Type 1 channel access procedure and the corresponding DL-PRS CAPC, and the gNB expects to transmit the DL data using the Type 1 channel access procedure and the corresponding CAPC, it can be achieved as follows:

[0125] ■ If the gap between the DL data transmission and the DL-PRS transmission is at most 25 microseconds, the gNB may determine a unified CAPC value. The unified CAPC value is related to the DL-PRS transmission duration and the DL data transmission duration. The maximum COT corresponding to the unified CAPC value may be greater than or equal to the total transmission duration of the DL-PRS transmission and the DL data transmission. The unified CAPC value is used to initiate channel occupancy at the start of the first DL transmission, and the Type 2 channel access procedure may be used to transmit the next DL transmission. If the gap between the DL data transmission and the DL-PRS transmission is greater than 25 microseconds, the gNB may initiate two COTs for the DL-PRS transmission and the DL data transmission respectively using the CAPC corresponding to the DL-PRS transmission and the DL data transmission.

[0126] ■ The gNB can initiate the COT of the first DL transmission using the corresponding CAPC value and transmit the first DL transmission. If the gap between the DL data transmission and the DL-PRS transmission is at most 25 microseconds, the Type 2 channel access procedure can be used to transmit the next DL transmission. If the gap between the DL data transmission and the DL-PRS transmission is greater than 25 microseconds, the gNB can initiate another COT of the next DL transmission using the corresponding CAPC value.

[0127] Figure 5 Sketches are provided for DL-PRS transmission with a gap after / before the DL data transmission.

[0128] For positioning SRS transmission, there are also cases where the positioning SRS transmission is performed after or before the UL data transmission. The above solutions for DL transmission can also be applied to UL transmission with positioning SRS and PUCCH / PUSCH.

[0129] Embodiment 4: DL-PRS / Positioning SRS transmission based on semi-static channel occupancy.

[0130] In Embodiment 1 and Embodiment 2, the Type 1 and Type 2 channel access procedures belong to dynamic channel access procedures. For DL / UL data transmission in the current NR-U, the periodic channel occupancy can be initiated by the gNB / UE, which is semi-static channel occupancy. The period of the semi-static channel occupancy consists of the maximum COT and the idle duration, where the idle duration follows the maximum COT and is at the end of the period. DL / UL transmission is performed during the maximum COT, while no DL / UL transmission is performed during the idle duration. However, how to transmit DL-PRS / positioning SRS based on semi-static channel occupancy is a problem. This embodiment provides some solutions for DL-PRS / positioning SRS transmission based on semi-static channel occupancy.

[0131] DL-PRS is a periodic reference signal and is transmitted in a periodic manner. If it is desired that the DL-PRS is transmitted at the start of the semi-static channel occupancy period, the DL-PRS period needs to be related to the semi-static channel occupancy period initiated by the gNB. Therefore, the DL-PRS period can be associated with the period of the semi-static channel occupancy initiated by the gNB. The association between the DL-PRS period and the semi-static channel occupancy period initiated by the gNB is one or more of the following:

[0132] ■ The DL-PRS period can be equal to the period of the semi-static channel occupancy initiated by the gNB.

[0133] ■ The DL-PRS period can be an integer multiple of the semi-static occupancy period initiated by the gNB.

[0134] If the gNB transmits DL-PRS within the COT of the semi-static channel occupancy initiated by the gNB / UE, there may be an association between the DL-PRS period, the slot offset of the DL-PRS resource set, the slot offset of the DL-PRS resource, the symbol offset of the DL-PRS resource, and the semi-static channel occupancy period, so as to ensure that the DL-PRS transmission ends before the start of the idle duration of the semi-static channel occupancy. If the DL-PRS transmission overlaps with the idle duration in a period of the semi-static channel occupancy, one or more of the following are applied, and detailed rules are provided in Embodiment 6:

[0135] ■ Discard the DL-PRS resources.

[0136] ■ Discard the symbols of the DL-PRS resources that overlap with the idle duration.

[0137] UL positioning SRS can be transmitted in a semi-persistent and periodic manner. If it is desired to transmit the positioning SRS at the start of the semi-static channel occupancy period initiated by the UE, the positioning SRS period needs to be related to the semi-static channel occupancy period initiated by the UE. Thus, the positioning SRS period can be associated with the semi-static channel occupancy period initiated by the UE. The association between the positioning SRS period and the semi-static channel occupancy period initiated by the UE is one or more of the following:

[0138] ■ The positioning SRS period can be equal to the semi-static channel occupancy period initiated by the UE.

[0139] ■ The positioning SRS period can be an integer multiple of the semi-static occupancy period initiated by the UE.

[0140] If the UE transmits the positioning SRS within the COT of the semi-static channel occupancy initiated by the UE / gNB, there may be an association between the positioning SRS period, the number of symbols of the positioning SRS, the starting symbol offset of the positioning SRS, and the semi-static channel occupancy period, so as to ensure that the positioning SRS transmission ends before the start of the idle duration of the semi-static channel occupancy. If the positioning SRS transmission overlaps with the idle duration in a period of the semi-static channel occupancy, one or more of the following are applied, and detailed rules are provided in Embodiment 6:

[0141] ■ Discard the positioning SRS resources.

[0142] ■ Discard the symbols of the positioning SRS resources that overlap with the idle duration.

[0143] Embodiment 5: Specific configuration of semi-static channel occupancy for DL-PRS / positioning SRS.

[0144] In Embodiment 4, by configuring the parameters of DL-PRS / positioning SRS, DL-PRS / positioning SRS transmission can be performed based on the current semi-static channel occupancy. Another solution for the periodic transmission of DL-PRS / positioning SRS is to configure the specific parameters of the semi-static channel occupancy of DL-PRS / positioning SRS. In this embodiment, the specific parameters of the semi-static channel occupancy of DL-PRS / positioning SRS are configured.

[0145] The gNB can initiate semi-static channel occupancy for DL-PRS transmission on a channel within the bandwidth of the serving cell, and there is no restriction on the number of radio frames. The DL-PRS semi-static channel occupancy period can be related to the DL-PRS period. The association between the DL-PRS semi-static channel occupancy period and the DL-PRS period can be one or more of the following:

[0146] ■ The DL-PRS semi-static channel occupancy period can be equal to the DL-PRS period.

[0147] ■ The DL-PRS semi-static channel occupancy period can be an integer multiple of the DL-PRS period.

[0148] The time offset of the first period of the DL-PRS semi-static channel occupancy relative to the reference time can be configured, where the reference time can be SFN0 / DFN0. This time offset of the first period of the DL-PRS semi-static channel occupancy can be associated with the time offset of the DL-PRS transmission, where the time offset of the DL-PRS transmission depends on the slot offset of the DL-PRS resource set, the slot offset of the DL-PRS resource, and the symbol offset of the DL-PRS resource. Specifically, the time offset of the first period of the DL-PRS semi-static channel occupancy can be equal to the time offset of the DL-PRS transmission.

[0149] The DL-PRS semi-static channel occupancy period and the time offset of the first period of the DL-PRS semi-static channel occupancy can be determined by the higher layer of the gNB (e.g., the RRC of the gNB). Alternatively, the DL-PRS semi-static channel occupancy period and the time offset of the first period of the DL-PRS semi-static channel occupancy can be pre-configured. Alternatively, the DL-PRS semi-static channel occupancy period and the time offset of the first period of the DL-PRS semi-static channel occupancy can be configured by the LMF and transmitted to the gNB via NRPPa.

[0150] The semi-static channel occupancy initiated by the gNB for DL-PRS transmission purposes can be used to transmit DL data and is shared to transmit UL data / positioning SRS.

[0151] The UE may initiate semi-static channel occupancy for positioning SRS transmission on a channel within the bandwidth of the serving cell, and there is no limit on the number of radio frames. The semi-static channel occupancy period for positioning SRS may be related to the positioning SRS period. The association between the semi-static channel occupancy period for positioning SRS and the positioning SRS period may be one or more of the following:

[0152] ■ The semi-static channel occupancy period for positioning SRS may be equal to the positioning SRS period.

[0153] ■ The semi-static channel occupancy period for positioning SRS may be an integer multiple of the positioning SRS period.

[0154] The time offset of the first period of the semi-static channel occupancy for positioning SRS with respect to a reference time can be configured, and the reference time can be SFN0 / DFN0. The time offset of the first period of the semi-static channel occupancy for positioning SRS may be associated with the time offset of the positioning SRS transmission, where the time offset of the positioning SRS transmission depends on the starting symbol offset of the positioning SRS. Specifically, the time offset of the first period of the semi-static channel occupancy for positioning SRS may be equal to the time offset of the positioning SRS transmission.

[0155] The semi-static channel occupancy period for positioning SRS and the time offset of the first period of the semi-static channel occupancy for positioning SRS may be configured by the higher layer of the gNB (e.g., the RRC of the gNB). Alternatively, the semi-static channel occupancy period for positioning SRS and the time offset of the first period of the semi-static channel occupancy for positioning SRS may be determined by the higher layer of the UE (e.g., the RRC of the UE). Alternatively, the semi-static channel occupancy period for positioning SRS and the time offset of the first period of the semi-static channel occupancy for positioning SRS are pre-configurable. Alternatively, the semi-static channel occupancy period for positioning SRS and the time offset of the first period of the semi-static channel occupancy for positioning SRS may be configured by the LMF and transmitted to the UE via LPP.

[0156] The semi-static channel occupancy initiated by the UE for positioning SRS transmission may be used to transmit UL data and shared to transmit DL data / DL-PRS.

[0157] Example 6: DL-PRS / Positioning SRS resources recommended by the LMF in semi-static channel occupancy.

[0158] In semi-static channel occupancy, the gNB / UE performs sensing during the idle duration of the previous cycle of the COT in the adjacent next cycle. To increase the success probability of channel access, there may not be any gNB / UE performing DL / UL transmission during the idle duration. Thus, if the gNB initiates semi-static channel occupancy, the semi-static channel occupancy related information can be reported to the LMF. If there are multiple gNBs initiating semi-static channel occupancy, they all transmit their respective semi-static channel occupancy related information to the LMF. The semi-static channel occupancy related information includes at least one or more of the following: the semi-static channel occupancy period, the time of the idle duration, and the COT length. When the LMF receives the semi-static channel occupancy related information, it can recommend DL-PRS transmission resources to the gNB, and the recommended DL-PRS transmission resources can avoid the time-frequency resources occupied by multiple idle durations. Alternatively, the LMF can also transmit the semi-static channel occupancy related information / idle duration related information of other gNBs to the gNB. The idle duration related information includes at least one or more of the following: the time of the idle duration, the frequency resources of the idle duration. When the gNB receives the semi-static channel occupancy related information / idle duration related information of other gNBs, it can determine the DL-PRS transmission resources by avoiding the time-frequency resources occupied by the idle durations of other gNBs. Alternatively, the LMF can transmit non-preferred resources for DL-PRS transmission to the gNB, where the non-preferred resources for DL-PRS transmission are associated with the idle durations of multiple gNBs and the resources occupied by the idle durations of multiple gNBs. When the gNB receives the non-preferred resources for DL-PRS transmission, it can determine the DL-PRS transmission resources by avoiding the non-preferred resources for DL-PRS transmission.

[0159] If the UE initiates semi-static channel occupancy, the semi-static channel occupancy related information can be reported to the LMF. If multiple UEs initiate semi-static channel occupancy, they each transmit their semi-static channel occupancy related information to the LMF. The semi-static channel occupancy related information includes at least one or more of: the semi-static channel occupancy period, the time of the idle duration, and the COT length. When the LMF receives the semi-static channel occupancy related information, it can recommend positioning SRS transmission resources to the serving gNB, and the recommended positioning SRS transmission resources can avoid the time-frequency resources occupied by multiple idle durations. Alternatively, the LMF can also transmit the semi-static channel occupancy related information / idle duration related information of other UEs to the serving gNB. The idle duration related information includes at least one or more of: the time of the idle duration, the idle duration frequency resources. When the serving gNB receives the semi-static channel occupancy related information / idle duration related information of other UEs, it can determine the positioning SRS transmission resources by avoiding the time-frequency resources occupied by the idle durations of other UEs. Alternatively, the LMF can transmit non-preferred resources for positioning SRS transmission to the serving gNB, where the non-preferred resources for positioning SRS transmission are associated with the idle durations of multiple UEs and the resources occupied by the idle durations of multiple UEs. When the serving gNB receives the non-preferred resources for positioning SRS transmission, it can determine the positioning SRS transmission resources by avoiding the non-preferred resources for positioning SRS transmission.

[0160] Embodiment 7: Use some resources / symbols within the COT for DL-PRS transmission.

[0161] Since the configuration of DL-PRS (including the transmission time of DL-PRS) is configured by the LMF and the COT is initiated by the gNB, there may be two cases: the start time of DL-PRS transmission is before the start of the COT, and the end time of DL-PRS transmission is after the end of the COT. In these two cases, some DL-PRS resources / symbols are outside the COT, and some DL-PRS resources / symbols are within the COT. In this case, how to transmit the DL-PRS resources is a problem. In this embodiment, some rules and configurations are provided for using some resources / symbols within the COT for DL-PRS transmission.

[0162] The gNB is configured to transmit multiple DL-PRS resources, and the gNB performs channel access for DL-PRS transmission. One case is that the gNB can initiate channel occupancy after the transmission time of some DL-PRS resources, as Figure 6 shown. Another case is that after the COT ends, the DL-PRS transmission has not ended, as Figure 7As shown. These two cases result in some DL-PRS resources / symbols being within the COT and some DL-PRS resources / symbols being outside the COT.

[0163] Figure 6 Shows a COT initiated after the transmission time of some DL-PRS resources. Figure 7 Shows a COT that ends before the transmission time of some DL-PRS resources. One solution is for the gNB to determine for each DL-PRS resource whether to transmit the DL-PRS transmission. If the transmission time of a DL-PRS resource is completely within the COT, the DL-PRS resource can be transmitted by the gNB in the COT. If part of the transmission time of a DL-PRS resource is within the COT and some transmission time is outside the COT, the DL-PRS resource is discarded and cannot be transmitted. If the transmission time of a DL-PRS resource is completely outside the COT, the DL-PRS resource is discarded and cannot be transmitted.

[0164] Another solution is that the gNB can determine for each DL-PRS symbol whether to transmit the DL-PRS transmission. As Figure 8 and Figure 9 shown, some symbols of a DL-PRS resource are outside the COT and some symbols are within the COT. One or more of the following rules can be applied to determine whether / how to transmit the DL-PRS resource:

[0165] ■ If all symbols of a DL-PRS resource are within the COT, the DL-PRS resource can be transmitted in the COT. Otherwise, the DL-PRS resource is discarded and cannot be transmitted in the COT.

[0166] ■ Or, if the number of symbols of a DL-PRS resource that are within the COT is not less than a threshold, the DL-PRS symbols within the COT can be transmitted in the COT, while the DL-PRS symbols outside the COT are discarded and cannot be transmitted. The threshold can be configured / determined by the LMF / gNB. The threshold can be related to the number of symbols of the DL-PRS resource. The threshold can be associated with the comb size of the DL-PRS resource.

[0167] ■ Or, some patterns can be configured / determined by the LMF / gNB. If the DL-PRS symbols within the COT are the same as or include the configured pattern, the DL-PRS symbols that meet the configured pattern can be transmitted in the COT, while other DL-PRS symbols can be discarded and cannot be transmitted. The pattern can be related to the comb size and comb offset of the DL-PRS resource.

[0168] Figure 8Shows the COT initiated after some DL-PRS symbol transmissions. Figure 9 Shows the COT ended before some DL-PRS symbol transmissions. For UL positioning SRS transmissions, there are also the following cases: some positioning SRS resources / symbols are outside the COT, while some positioning SRS resources / symbols are inside the COT. In such cases, whether / how to transmit the positioning SRS is a problem. The solutions described above for DL-PRS transmissions can be applied to UL positioning SRS transmissions. In semi-static channel occupancy, the DL-PRS / positioning SRS transmission time can overlap with the idle duration. If the DL-PRS / positioning SRS transmission occurs during the idle duration, the above solutions can be applied to transmit the DL-PRS / positioning SRS.

[0169] Embodiment 8: DL-PRS transmission from multiple gNBs based on a dynamic channel access procedure.

[0170] To obtain the UE's position estimate through the Downlink Time Difference of Arrival (DL-TDOA) method and the Multiple-Round Trip Time (Multi-RTT) method, multiple gNBs need to transmit DL-PRS to the UE. In the current NR-U, the serving gNB accesses the channel through a channel access procedure to transmit data, while the neighboring gNBs do not access the channel for data transmission. How to enable multiple gNBs to access the channel to transmit DL-PRS is a problem. In this embodiment, a solution for channel access is provided for multiple gNBs to transmit DL-PRS.

[0171] Neighboring gNBs may be allowed to access the channel to transmit DL-PRS based on Type 1 and / or Type 2 channel access procedures.

[0172] If the serving gNB initiates the channel occupancy for DL-PRS transmission using the Type 1 channel access procedure, the DL-PRS channel occupancy window related information can be notified by the serving gNB to the neighboring gNBs. The serving gNB can notify the DL-PRS channel occupancy window related information to the neighboring gNBs via the following ways:

[0173] ■ The Xn interface.

[0174] ■ Or, completed by the LMF through NRPPa. That is, the serving gNB transmits the DL-PRS channel occupancy window related information to the LMF via NRPPa

[0175] and then the LMF transmits the DL-PRS channel occupancy window related information to the neighboring gNBs via NRPPa.

[0176] In the DL-PRS channel occupancy window, the serving gNB and adjacent gNBs only transmit DL-PRS. In this case, for the DL-PRS transmission of adjacent gNBs within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0177] ■ The adjacent gNB can transmit DL-PRS without sensing.

[0178] ■ Alternatively, the adjacent gNB can transmit DL-PRS immediately after detecting at least one sensing time slot duration of idle, where the sensing time slot is 9 microseconds.

[0179] ■ Alternatively, the adjacent gNB can access the channel within the DL-PRS channel occupancy window based on the Type 2 channel access procedure to transmit DL-PRS.

[0180] Alternatively, in the DL-PRS channel occupancy window, the serving gNB can transmit DL-PRS and DL data, while the adjacent gNBs can only transmit DL-PRS. In this case, for the DL-PRS transmission of adjacent gNBs within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0181] ■ The adjacent gNB can transmit DL-PRS immediately after detecting at least one sensing time slot duration of idle, where the sensing time slot is 9 microseconds.

[0182] ■ Alternatively, the adjacent gNB can access the channel within the DL-PRS channel occupancy window based on the Type 2 channel access procedure to transmit DL-PRS.

[0183] The DL-PRS channel occupancy window length is not greater than the maximum COT. For the configuration / determination of the DL-PRS channel occupancy window length, it can be achieved in the following ways:

[0184] ■ The DL-PRS channel occupancy window length is configured by the higher layer of the gNB (e.g., the RRC of the gNB).

[0185] ■ Alternatively, the DL-PRS channel occupancy window length is associated with the CAPC. That is, there is a mapping relationship between the DL-PRS channel occupancy window length and the CAPC. If the CAPC is indicated, the DL-PRS channel occupancy window length can be obtained.

[0186] The DL-PRS channel occupancy window related information includes at least one or more of the following:

[0187] ■ The CAPC for initiating channel occupancy;

[0188] ■ The channel occupancy time;

[0189] ■ Start time of channel occupancy;

[0190] ■ DL-PRS channel occupancy window length;

[0191] ■ Start time of the DL-PRS channel occupancy window.

[0192] The neighboring gNB that can receive the information related to the DL-PRS channel occupancy window can be determined by the serving gNB. Alternatively, the neighboring gNB can be determined by the UE, and the UE reports the identifier of the neighboring gNB to the serving gNB through the Physical Uplink Control Channel / Physical Uplink Shared Channel (PUCCH / PUSCH). Alternatively, the neighboring gNB can be configured by the LMF, and the LMF transmits the identifier information of the neighboring gNB to the serving gNB via NRPPa. If the serving gNB receives the identifier of the neighboring gNB, the serving gNB can notify the information related to the DL-PRS channel occupancy window to these neighboring gNBs.

[0193] If the neighboring gNB initiates channel occupancy for DL-PRS transmission using the Type 1 channel access procedure, the neighboring gNB can notify the information related to channel occupancy to other gNBs. The neighboring gNB can notify the information related to channel occupancy to other gNBs in the following ways:

[0194] ■ Xn interface.

[0195] ■ Alternatively, it is completed by the LMF through NRPPa. That is, the neighboring gNB transmits the information related to channel occupancy to the LMF via NRPPa

[0196] and then the LMF transmits the information related to channel occupancy to other gNBs via NRPPa.

[0197] Within the COT initiated by the neighboring gNB, the serving gNB and all neighboring gNBs only transmit DL-PRS. For the DL-PRS transmission of the gNB within the COT, it can be achieved in the following ways:

[0198] ■ The gNB can transmit DL-PRS without sensing.

[0199] ■ Alternatively, the gNB can transmit DL-PRS immediately after detecting that at least one sensing time slot duration is idle, where the sensing time slot is 9 microseconds.

[0200] ■ Alternatively, the gNB can access the channel within the COT based on the Type 2 channel access procedure to transmit DL-PRS.

[0201] The information related to channel occupancy includes one or more of the following:

[0202] ■ CAPC for initiating channel occupancy;

[0203] ■ Channel occupancy time;

[0204] ■ Start time of channel occupancy.

[0205] Other gNBs that receive DL-PRS channel occupancy window related information can be determined by the initiating gNB. Alternatively, other gNBs can be configured by the LMF, and the LMF can transmit the identification information of other gNBs to the initiating gNB via NRPPa. If the initiating gNB receives the identification of other gNBs, the initiating gNB will inform other gNBs of the DL-PRS channel occupancy window related information.

[0206] Embodiment 9: DL-PRS transmission from multiple gNBs based on semi-static channel access procedures.

[0207] In Embodiment 6, multiple gNBs access the channel for DL-PRS transmission based on dynamic channel access procedures. In the unlicensed band, another solution is based on semi-static channel occupancy to allow multiple gNBs to access the channel for DL-PRS transmission.

[0208] The serving gNB can initiate semi-static channel occupancy for DL-PRS transmission. If the DL-PRS is transmitted by the serving gNB at the start of the semi-static channel occupancy period, the serving gNB will inform the adjacent gNBs of the DL-PRS channel occupancy window related information. The serving gNB informs the adjacent gNBs of the DL-PRS channel occupancy window related information in the following ways:

[0209] ■ Xn interface.

[0210] ■ Alternatively, it is completed by the LMF via NRPPa. That is, the serving gNB transmits the DL-PRS channel occupancy window related information to the LMF via NRPPa, and then the LMF transmits the DL-PRS channel occupancy window related information to the adjacent gNBs via NRPPa.

[0211] In the DL-PRS channel occupancy window, only the serving gNB and adjacent gNBs transmit DL-PRS. In this case, for the DL-PRS transmission of adjacent gNBs within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0212] ■ The adjacent gNB can transmit DL-PRS without sensing.

[0213] ■ Alternatively, the adjacent gNB can transmit DL-PRS immediately after detecting at least one sensing time slot duration idle, where the sensing time slot is 9 microseconds.

[0214] ■ Alternatively, an adjacent gNB may access a channel within the DL-PRS channel occupancy window based on the Type 2 channel access procedure to transmit DL-PRS.

[0215] Alternatively, within the DL-PRS channel occupancy window, the serving gNB may transmit DL-PRS and DL data, while an adjacent gNB may only transmit DL-PRS. In this case, for the DL-PRS transmission of an adjacent gNB within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0216] ■ The adjacent gNB may transmit DL-PRS immediately after detecting at least one sensing time slot duration being idle, where the sensing time slot is 9 microseconds.

[0217] ■ Alternatively, an adjacent gNB may access a channel within the DL-PRS channel occupancy window based on the Type 2 channel access procedure to transmit DL-PRS.

[0218] The length of the DL-PRS channel occupancy window is not greater than the maximum COT of the semi-static channel occupancy period. For the configuration / determination of the length of the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0219] ■ The length of the DL-PRS channel occupancy window is configured by a higher layer of the gNB (e.g., the RRC of the gNB).

[0220] ■ Alternatively, the length of the DL-PRS channel occupancy window is associated with the semi-static channel occupancy period. That is, there is a mapping relationship between the length of the DL-PRS channel occupancy window and the semi-static channel occupancy period. If the semi-static channel occupancy period is determined, the length of the DL-PRS channel occupancy window can be obtained.

[0221] The information related to the DL-PRS channel occupancy window includes one or more of the following:

[0222] ■ The semi-static channel occupancy period;

[0223] ■ The maximum COT of the semi-static channel occupancy period;

[0224] ■ The start time of the semi-static channel occupancy period;

[0225] ■ The length of the DL-PRS channel occupancy window;

[0226] ■ The start time of the DL-PRS channel occupancy window.

[0227] The neighboring gNB that receives the information related to the DL-PRS channel occupancy window can be determined by the serving gNB. Alternatively, the neighboring gNB can be determined by the UE, and the UE reports the identifier of the neighboring gNB to the serving gNB via the Physical Uplink Control Channel / Physical Uplink Shared Channel PUCCH / PUSCH. Alternatively, the neighboring gNB can be configured by the LMF, and the LMF transmits the identifier information of the neighboring gNB to the serving gNB via NRPPa. If the serving gNB receives the identifier of the neighboring gNB, the serving gNB informs the neighboring gNB of the information related to the DL-PRS channel occupancy window.

[0228] The neighboring gNB can initiate semi-static channel occupancy for DL-PRS transmission. If the neighboring gNB initiates semi-static channel occupancy for DL-PRS transmission, the neighboring gNB can notify other gNBs of the information related to the channel occupancy. The neighboring gNB can notify other gNBs of the information related to the channel occupancy in the following ways:

[0229] ■ The Xn interface;

[0230] ■ Alternatively, it is completed by the LMF via NRPPa. That is, the neighboring gNB transmits the information related to the channel occupancy to the LMF via NRPPa, and then the LMF transmits the information related to the channel occupancy to other gNBs via NRPPa.

[0231] Within the COT of the semi-static channel occupancy period initiated by the neighboring gNB, the serving gNB and all neighboring gNBs can only transmit DL-PRS. For the DL-PRS transmission of the gNB within the COT of the period, it can be achieved in the following ways:

[0232] ■ The gNB can transmit DL-PRS without performing sensing.

[0233] ■ Alternatively, the gNB can transmit DL-PRS immediately after detecting that at least one sensing time slot duration is idle, where the sensing time slot is 9 microseconds.

[0234] ■ Alternatively, the gNB can access the channel within the COT based on the Type 2 channel access procedure to transmit DL-PRS.

[0235] The information related to the channel occupancy includes one or more of the following:

[0236] ■ The semi-static channel occupancy period;

[0237] ■ The maximum COT of the semi-static channel occupancy period;

[0238] ■ The start time of the semi-static channel occupancy period.

[0239] Other gNBs that receive information related to the DL-PRS channel occupancy window can be determined by the initiating gNB. Alternatively, other gNBs can be configured by the LMF, and the LMF will transmit the identification information of the other gNBs to the initiating gNB via NRPPa. If the initiating gNB receives the identification of the other gNBs, the initiating gNB will inform these other gNBs of the information related to the DL-PRS channel occupancy window.

[0240] The serving gNB and adjacent gNBs can share the COT initiated by the UE to transmit DL-PRS.

[0241] If the UE initiates semi-static channel occupancy and no channel occupancy sharing information is configured, the serving gNB can share the COT of the semi-static channel occupancy based on the Type 2 channel access procedure. The channel occupancy sharing information can be provided by the IE cg-COT-SharingList-r16. If the serving gNB successfully shares the COT of the semi-static channel occupancy initiated by the UE, the serving gNB can notify the adjacent gNBs of the information related to the DL-PRS channel occupancy window. The serving gNB can notify the adjacent gNBs of the information related to the DL-PRS channel occupancy window in the following ways:

[0242] ■ The Xn interface;

[0243] ■ Alternatively, it is completed by the LMF via NRPPa. That is, the serving gNB transmits the information related to the DL-PRS channel occupancy window to the LMF via NRPPa, and then the LMF transmits the information related to the DL-PRS channel occupancy window to the adjacent gNBs via NRPPa.

[0244] In the DL-PRS channel occupancy window, the serving gNB and adjacent gNBs only transmit DL-PRS. In this case, for the DL-PRS transmission of the adjacent gNBs within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0245] ■ The adjacent gNB can transmit DL-PRS without sensing.

[0246] ■ Alternatively, the adjacent gNB can transmit DL-PRS immediately after detecting at least one sensing time slot duration of idle, where the sensing time slot is 9 microseconds.

[0247] ■ Alternatively, the adjacent gNB can access the DL-PRS based on the Type 2 channel access procedure

[0248] The channel within the channel occupancy window is used to transmit DL-PRS.

[0249] Alternatively, in the DL-PRS channel occupancy window, the serving gNB may transmit DL-PRS and DL data, while the neighboring gNB may only transmit DL-PRS. In this case, for the DL-PRS transmission of the neighboring gNB within the DL-PRS channel occupancy window, it can be achieved in the following ways:

[0250] ■ The neighboring gNB may transmit DL-PRS immediately after detecting at least one sensing time slot duration of idle, where the sensing time slot is 9 microseconds.

[0251] ■ Alternatively, the neighboring gNB may access the channel within the DL-PRS channel occupancy window based on the Type 2 channel access procedure to transmit DL-PRS.

[0252] The DL-PRS transmissions of the serving gNB and the neighboring gNB may end before the start of the idle duration of the semi-static channel occupancy. The DL-PRS channel occupancy window length is not greater than the maximum COT of the semi-static channel occupancy. If the serving gNB detects a UL transmission in time slot n1 and the COT ends in time slot n2, then the DL-PRS channel occupancy window length is not greater than n2 - n1. The DL-PRS channel occupancy window length may be configured by the higher layer of the gNB (e.g., the RRC of the gNB). The DL-PRS channel occupancy window may start from the detection time of the UL transmission. Alternatively, the start time of the DL-PRS channel occupancy window may be later than the detection time of the UL transmission, which is configured / determined by the higher layer of the gNB.

[0253] The DL-PRS channel occupancy window related information includes one or more of the following:

[0254] ■ The semi-static channel occupancy period initiated by the UE;

[0255] ■ The maximum COT of the semi-static channel occupancy period initiated by the UE;

[0256] ■ The start time of the semi-static channel occupancy period initiated by the UE;

[0257] ■ The DL-PRS channel occupancy window length;

[0258] ■ The start time of the DL-PRS channel occupancy window.

[0259] The neighboring gNBs that receive the DL-PRS channel occupancy window related information can be determined by the serving gNB. Alternatively, the neighboring gNBs can be determined by the UE, and the UE reports the identifiers of the neighboring gNBs to the serving gNB through the Physical Uplink Control Channel / Physical Uplink Shared Channel PUCCH / PUSCH. Alternatively, the neighboring gNBs can be configured by the LMF, and the LMF transmits the identifier information of the neighboring gNBs to the serving gNB via NRPPa. If the serving gNB receives the identifiers of the neighboring gNBs, the serving gNB notifies these neighboring gNBs of the DL-PRS channel occupancy window related information.

[0260] If the UE initiates a semi-static channel occupancy with configured grant transmission and is configured with channel occupancy sharing information, the serving gNB can share the COT of the semi-static channel occupancy by detecting the Uplink Control Information (UCI), where the UCI carries the COT sharing information. The channel occupancy sharing information can be provided by the IE cg-COT-SharingList-r16. The COT sharing information can be provided by the IE CG-COT-Sharing-R16. In the COT sharing information, the sharing offset and the sharing duration can be provided and carried in the UCI. If the serving gNB detects the UCI including the COT sharing information in slot n, the serving gNB can start the DL transmission from slot n + sharing offset, and the DL transmission duration is indicated by the sharing duration. The DL transmission can be DL-PRS. If the DL-PRS transmission is DL-PRS, the serving gNB notifies the neighboring gNBs of the DL-PRS channel occupancy window related information. The DL-PRS channel occupancy window length is not greater than the sharing duration indicated in the UCI. The DL-PRS channel occupancy window can start from slot n + sharing offset. Alternatively, the start time of the DL-PRS channel occupancy window can be later than slot n + sharing offset, which can be configured / determined by the higher layer of the gNB.

[0261] Another solution is that the UE initiates semi-static channel occupancy with configured grant transmissions and can be configured with specific channel occupancy sharing information for DL-PRS transmissions. The specific channel occupancy sharing information for DL-PRS transmissions can be configured by the higher layer of the gNB (e.g., the RRC of the gNB). Specifically, the higher layer of the gNB can configure a specific channel occupancy sharing list for DL-PRS transmissions, and the list includes multiple rows indicating channel occupancy sharing information. Among the multiple rows of the specific channel occupancy sharing list for DL-PRS transmissions, one row indicates that the channel occupancy is unavailable, and the other rows provide specific channel occupancy sharing information for DL-PRS transmissions. Each row indicating specific channel occupancy sharing information includes at least a specific DL-PRS sharing offset and a specific DL-PRS sharing duration. Each row is indicated by a row index. The specific channel occupancy sharing information for DL-PRS transmissions indicated by the row index can be carried in the UCI. If the serving gNB detects the UCI including specific channel occupancy information for DL-PRS in slot n, the serving gNB can start transmitting DL-PRS from slot n + specific DL-PRS sharing offset, and the DL-PRS transmission duration is indicated by the specific DL-PRS sharing duration. And the serving gNB informs the adjacent gNB of the DL-PRS channel occupancy window related information. The DL-PRS channel occupancy window length is not greater than the specific DL-PRS sharing duration indicated in the UCI. The DL-PRS channel occupancy window can start from slot n + specific DL-PRS sharing offset. Alternatively, the start time of the DL-PRS channel occupancy window can be later than slot n + specific DL-PRS sharing offset, which can be configured / determined by the higher layer of the gNB.

[0262] The mechanism and configuration for sharing DL-PRS transmissions of multiple gNBs that share the semi-static channel occupancy initiated by the UE can be applied to the DL-PRS transmissions of multiple gNBs that share the COT initiated by the UE based on the dynamic channel access procedure.

[0263] Example 10: Define channel access for DL-PRS transmissions in the frequency domain.

[0264] In the bandwidth part (BWP) serving the gNB, DL transmissions using the Physical Downlink Control Channel / Physical Downlink Shared Channel (PDCCH / PDSCH) and UL transmissions using the PUCCH / PUSCH / SRS are carried out. The frequency configuration of the DL-PRS resources is defined in the Physical Frequency Layer (PFL) and is independent of the BWP. How to access the channels for SL-PRS transmissions in the PFL in the unlicensed band is a problem. In this embodiment, in the PFL of the unlicensed band, some configurations and procedures are introduced for DL-PRS transmissions.

[0265] In the current NR-U, a channel refers to a set of RBs. One BWP of the serving gNB includes an integer number of RB sets. A guard band can be configured between two consecutive RB sets. In the unlicensed band, the PFL can be configured to include an integer number of RB sets, where one RB set is a channel. In the PFL of the unlicensed band, the channel access operation is carried out on a per-RB-set basis. The guard band between two consecutive RB sets can be configured by the higher layer of the gNB in the PFL. Alternatively, in the PFL, there is no guard band between two consecutive RB sets. DL-PRS is transmitted in the PFL of the unlicensed band.

[0266] The gNB can access multiple channels for DL transmissions. Assume that the set of multiple channels on which DL transmissions are performed is C. Each channel is c_i, where c_i ∈ C, i = 0, 1, … q - 1, and q is the number of channels on which DL transmissions are performed. In the current NR-U, there are two types of multi-channel access, which are Type A multi-channel access procedure and Type B multi-channel access procedure. In the Type A multi-channel access procedure, the gNB independently uses the Type 1 channel access procedure to access each channel. In the Type B multi-channel access procedure, the gNB first uniformly and randomly selects a channel c j , and the selection of c j does not exceed once per second. Then, the gNB uses the Type 1 channel access procedure to perform channel access on the channel c j . For other channels c i ≠ c j and c i ∈ C, a sensing operation with a fixed sensing duration for the channel c j is performed before transmission on the channel c i . If the channel c i is sensed to be idle during the fixed sensing duration, then transmission is carried out on the channel c i .

[0267] If the gNB expects to transmit DL-PRS on multiple channels, the Type A multi-channel access procedure and the Type B multi-channel access procedure can be applied to the DL-PRS transmission in the PFL. Parameters can be added to the configuration of the PFL, where the parameter can be the type of multi-channel access procedure. That is, the type of multi-channel access procedure can be configured according to the PFL. Alternatively, the type of multi-channel access procedure can be configured according to the positioning service. Alternatively, parameters can be added to the configuration of the DL-PRS resource set, where the parameter can be the type of multi-channel access procedure. That is, the type of multi-channel access procedure can be configured according to the DL-PRS resource set. Alternatively, parameters can be added to the configuration of the DL-PRS resource, where the parameter can be the type of multi-channel access procedure. That is, the type of multi-channel access procedure can be configured according to the DL-PRS resource.

[0268] Embodiment 11: Configuration of the DL-PRS transmission gap.

[0269] The gNB can configure the DL-PRS transmission gap, which is dedicated to DL-PRS transmission, reception, and measurement. For DL-PRS transmission / reception / measurement, one or more DL-PRS transmission gaps can be configured / activated by the higher layer of the gNB (e.g., the RRC of the gNB, the MAC CE of the gNB). Each DL-PRS transmission gap is associated with a DL-PRS transmission gap ID. The configuration of each DL-PRS transmission gap includes at least one of the following:

[0270] ■ DL-PRS transmission gap ID;

[0271] ■ DL-PRS transmission gap length;

[0272] ■ DL-PRS transmission gap period;

[0273] ■ Reference points in the time domain, e.g., SFN0, DFN0;

[0274] ■ Offset of the DL-PRS transmission gap relative to the reference point in the time domain.

[0275] During the DL-PRS transmission gap, the gNB can perform a channel access procedure before transmitting each DL-PRS resource and initiate channel occupancy for each DL-PRS resource transmission. That is, the channel access procedure can be performed by the gNB according to the DL-PRS resource. One or more of the following channel access procedures can be applied to initiate channel occupancy for DL-PRS resource transmission:

[0276] ■ Before transmitting the DL-PRS resource, the gNB performs a sensing operation for at least one sensing time slot, where one sensing time slot is 9 microseconds. If it is sensed that at least one sensing time slot is idle, the gNB transmits the DL-PRS resource after the sensing time slot.

[0277] ■ Alternatively, before transmitting the DL-PRS resource, the gNB performs a sensing operation for at least one sensing interval, where the sensing interval is 25 microseconds. The sensing interval includes two sensing time slots, where the sensing time slot is 9 microseconds, and one sensing time slot is at the start of the sensing interval, while the other sensing time slot is at the end of the sensing interval. If both sensing time slots of the sensing interval are sensed as idle, the gNB transmits the DL-PRS resource immediately after the sensing interval.

[0278] ■ Alternatively, before transmitting the DL-PRS resource, the gNB performs a sensing operation for at least one sensing duration, where the sensing duration is 16 microseconds. The sensing duration includes one sensing time slot, where the sensing time slot is 9 microseconds and at the end of the sensing duration. If within the sensing duration, a total of at least 5 microseconds are sensed as being idle, where at least 4 microseconds occur within the sensing time slot, the gNB transmits the DL-PRS resource immediately after the sensing duration.

[0279] ■ Alternatively, the gNB may initiate a COT for DL-PRS resource transmission based on the Type 1 channel access procedure using the CAPC value corresponding to the DL-PRS

[0280] resource.

[0281] If the gap between two DL-PRS resources is less than one sensing time slot / 16 microseconds, the gNB may initiate the channel occupancy of the first DL-PRS resource and directly transmit the next DL-PRS resource without performing sensing. However, if the channel access operation is performed before each DL-PRS resource transmission, the gNB needs to sense frequently and the failure probability of channel occupancy is high. To reduce the number of channel access operations and increase the success probability of channel occupancy, the gNB may configure multiple candidate COTs for DL-PRS transmission in each DL-PRS transmission gap. Thus, in addition to the above configuration for each DL-PRS transmission gap, the configuration of the DL-PRS transmission gap may further include the number of candidate COTs and the candidate COT configuration. Figure 10 A schematic diagram of the DL-PRS transmission gap and the candidate COT is shown. The candidate COT may be configured by the higher layer of the gNB (e.g., the RRC of the gNB, the MAC CE of the gNB). The candidate COT in the DL-PRS transmission gap may be periodic or aperiodic.

[0282] If the candidate COT in the DL-PRS transmission gap is periodic, the configuration of the candidate COT includes at least:

[0283] ■ Candidate COT ID;

[0284] ■ Candidate COT length;

[0285] ■ Candidate COT period;

[0286] ■ Offset of the first candidate COT with respect to the start time of the DL-PRS transmission gap.

[0287] If the candidate COT in the DL-PRS transmission gap is aperiodic, the configuration of the candidate COT includes at least:

[0288] ■ Candidate COT ID;

[0289] ■ Candidate COT length;

[0290] ■ Offset of the candidate COT with respect to the start time of the DL-PRS transmission gap.

[0291] Figure 10 A schematic diagram of the DL-PRS transmission gap and the candidate COT is provided. The candidate COT can be configured according to the DL-PRS transmission gap. That is, for different DL-PRS transmission gaps, the configuration of the candidate COT is different. Alternatively, the candidate COT can also be configured according to the PFL. That is, for the DL-PRS transmission gaps in the same PFL, the configuration of the candidate COT is the same. For the DL-PRS transmission gaps in different PFLs, the configuration of the candidate COT is different. Alternatively, the candidate COT can also be configured according to the serving cell. That is, different gNBs can configure different candidate COTs. Alternatively, the candidate COT can also be configured according to the UE. That is, if it is desired that the same UE receives and measures the DL-PRS transmission, different gNBs can configure the same candidate COT.

[0292] For the DL-PRS resource, the gNB determines which candidate COT the DL-PRS resource transmission time belongs to based on the configuration of the DL-PRS. Then, the gNB performs channel access before the candidate COT to which the DL-PRS resource transmission time belongs. One or more of the following channel access procedures can be applied before the candidate COT:

[0293] ■ The gNB senses at least one sensing time slot before the candidate COT, where the sensing time slot is 9 microseconds. If at least one sensing time slot is sensed as idle, the candidate COT can be initiated for DL-PRS transmission.

[0294] ■ Alternatively, the gNB senses at least the sensing interval before the candidate COT, where the sensing interval is 25 microseconds. The sensing interval includes two sensing time slots, where the sensing time slot is 9 microseconds, and where one sensing time slot is at the start of the sensing interval and the other sensing time slot is at the end of the sensing interval. If both sensing time slots of the sensing interval are sensed as idle, the candidate COT can be initiated for DL-PRS transmission.

[0295] ■ Alternatively, the gNB senses at least the sensing duration before the candidate COT, where the sensing duration is 16 microseconds. The sensing duration includes one sensing time slot, where the sensing time slot is 9 microseconds and at the end of the sensing duration. If within the sensing duration, in total at least 5 microseconds are sensed as idle, where at least 4 microseconds occur within the sensing time slot, the candidate COT can be initiated for DL-PRS transmission.

[0296] If the candidate COT is initiated, the gNB can transmit the DL-PRS starting at the start of the candidate COT. If the gNB does not transmit the DL-PRS transmission at the start of the initiated candidate COT and the duration between the start of the initiated candidate COT and the DL-PRS transmission time is at most one sensing time slot / 16 microseconds, the gNB can directly transmit the DL-PRS at the DL-PRS transmission time. If the gNB does not transmit the DL-PRS transmission at the start of the initiated candidate COT and the duration between the start of the initiated candidate COT and the DL-PRS transmission time is greater than one sensing time slot / 16 microseconds, the gNB may need to sense at least one sensing time slot immediately before the DL-PRS transmission. If at least one sensing time slot is sensed as idle, the gNB can transmit the DL-PRS immediately after the sensing time slot.

[0297] In the initiated candidate COT, the gNB can transmit multiple DL-PRS resources. If there is a gap between the current DL-PRS resource and the previous DL-PRS resource, the Type 2 channel access procedure can be used for the current DL-PRS resource. Alternatively, if the gap between the current DL-PRS resource and the previous DL-PRS resource is at most one sensing time slot / 16 microseconds, the current DL-PRS resource can be directly transmitted without sensing. If the gap between the current DL-PRS resource and the previous DL-PRS resource is greater than one sensing time slot / 16 microseconds, the gNB may need to sense at least one sensing time slot before the current DL-PRS resource. If at least one sensing time slot is sensed as idle, the gNB can transmit the current DL-PRS after the sensing time slot. Alternatively, the gNB can transmit multiple DL-PRS resources during the initiated candidate COT without sensing.

[0298] The candidate COTs initiated can be shared by the initiating gNB with other gNBs for DL-PRS transmission. Other gNBs can share the candidate COTs for DL-PRS transmission based on the Type 2 channel access procedure. Alternatively, based on Embodiment 8 and Embodiment 9, other gNBs can share the candidate COTs for DL-PRS transmission.

[0299] For DL-PRS resources, the gNB can initiate one or more candidate channel occupations starting at the first candidate COT. If the candidate channel occupation fails, the next candidate COT can be initiated. The gNB stops performing the channel access procedure for the remaining candidate COTs until one or more candidate COTs are successfully initiated. Alternatively, the gNB can initiate one or more candidate channel occupations starting at the candidate COT to which the DL-PRS transmission time belongs. If the candidate channel occupation fails, the next candidate COT can be initiated. The gNB stops performing the channel access procedure for the remaining candidate COTs until one or more candidate COTs are successfully initiated or the number of initiated candidate COTs reaches the maximum number of candidate COTs. The number of candidate COTs that the gNB needs to successfully initiate can be determined by the gNB.

[0300] Alternatively, within the DL-PRS transmission gap, the gNB may initiate channel occupancy based on the Type 1 channel access procedure. The maximum number of candidate COTs initiated using the Type 1 channel access procedure may be determined / configured by the gNB, where the total duration of all candidate COTs shall not be greater than the DL-PRS transmission gap length. For DL-PRS resource transmission, the gNB may initiate candidate COTs based on the Type 1 channel access procedure using the CAPC value corresponding to the DL-PRS resource transmission. If the candidate channel occupancy fails, the next candidate COT may be initiated based on the Type 1 channel access procedure using the CAPC value corresponding to the DL-PRS resource transmission. The gNB may stop performing the channel access procedure on the remaining candidate COTs using the CAPC value corresponding to the DL-PRS resource transmission until one or more candidate COTs are successfully initiated or the number of initiated candidate COTs reaches the maximum number of candidate COTs. The number of candidate COTs that the gNB needs to successfully initiate may be determined by the gNB. If the time gap between two DL-PRS resources is at most one sensing time slot / 16 microseconds, the gNB may initiate a COT to transmit the first DL-PRS resource and directly transmit the next DL-PRS resource without sensing. If the time gap between two DL-PRS resources is greater than one sensing time slot / 16 microseconds, the gNB needs to initiate a COT for the second DL-PRS resource based on the Type 1 channel access procedure using the CAPC value corresponding to the second DL-PRS resource transmission. Alternatively, if the time gap between two DL-PRS resources is greater than one sensing time slot / 16 microseconds and if the gNB has initiated a COT for the first DL-PRS resource, the gNB may sense at least one sensing time slot immediately before the second DL-PRS resource.

[0301] Alternatively, the configuration of each DL-PRS transmission gap may further include the repetition information of the DL-PRS transmission gap. The repetition information of the DL-PRS transmission gap includes at least: the repetition factor and the time gap between two repetitions of the DL-PRS transmission gap. Figure 11A schematic diagram regarding DL-PRS transmission gaps with multiple repetitions is shown. When repeating the DL-PRS transmission gap, one or more COTs can be initiated to transmit DL-PRS resources using the Type 1 / 2 channel access procedure. For DL-PRS transmission, the gNB can initiate a COT starting from the first repetition of the DL-PRS transmission gap. If the COT initiated in the first repetition of the DL-PRS transmission gap fails, the gNB can initiate a COT in the next repetition of the DL-PRS transmission gap until one or more COTs / repetitions are successfully occupied or the number of repetitions for initiating the COT reaches the maximum number of repetitions of the DL-PRS transmission gap. Alternatively, for DL-PRS resources, the gNB can determine which repetition of the DL-PRS transmission gap the DL-PRS resource transmission time belongs to based on the configuration of the DL-PRS. Then, the gNB initiates a COT for DL-PRS resource transmission within the repetition of the DL-PRS transmission gap to which the DL-PRS resource transmission time belongs. Figure 11 A schematic diagram regarding DL-PRS transmission gaps with repetitions is provided.

[0302] Example 12: Configuration of positioning SRS transmission gaps.

[0303] Similar to the DL-PRS transmission gap, the UE can configure a positioning SRS transmission gap, which is dedicated to positioning SRS transmission, reception, and measurement. For positioning SRS transmission / reception / measurement, one or more positioning SRS transmission gaps can be configured / activated / determined by the LMF / higher layer of the gNB / UE (e.g., the RRC of the gNB, the MAC CE of the gNB). Each positioning SRS transmission gap is associated with a positioning SRS transmission gap ID. The configuration of each positioning SRS transmission gap can at least include the following:

[0304] ■ Positioning SRS transmission gap ID;

[0305] ■ Positioning SRS transmission gap length;

[0306] ■ Positioning SRS transmission gap period;

[0307] ■ Reference points in the time domain, e.g., SFN0, DFN0;

[0308] ■ Offset of the positioning SRS transmission gap in the time domain relative to the reference point.

[0309] In the positioning SRS transmission gap, the UE can perform a channel access procedure before each positioning SRS resource transmission and initiate channel occupancy for each positioning SRS resource transmission. That is, the UE can execute the channel access procedure according to the positioning SRS resources. One or more of the following channel access procedures can be applied to initiate channel occupancy for positioning SRS resource transmission:

[0310] ■The UE senses at least one sensing time slot before transmitting the positioning SRS resource, where the sensing time slot is 9 microseconds. If at least one sensing time slot is sensed as idle, the UE transmits the positioning SRS resource after the sensing time slot.

[0311] ■Alternatively, the UE senses at least a sensing interval before transmitting the positioning SRS resource, where the sensing interval is 25 microseconds. The sensing interval includes two sensing time slots, where the sensing time slot is 9 microseconds, and where one sensing time slot is at the start of the sensing interval and the other sensing time slot is at the end of the sensing interval. If both sensing time slots of the sensing interval are sensed as idle, the UE transmits the positioning SRS resource after the sensing interval.

[0312] ■Alternatively, the UE senses at least a sensing duration before transmitting the positioning SRS resource, where the sensing duration is 16 microseconds. The sensing duration includes a sensing time slot, where the sensing time slot is 9 microseconds and at the end of the sensing duration. If within the sensing duration, a total of at least 5 microseconds are sensed as idle, where at least 4 microseconds occur within the sensing time slot, the UE transmits the positioning SRS resource after the sensing duration.

[0313] ■Alternatively, the UE can initiate a COT for positioning SRS resource transmission based on the Type 1 channel access procedure using the CAPC value corresponding to the positioning SRS resource.

[0314] If the gap between two positioning SRS resources is less than one sensing time slot / 16 microseconds, the UE can initiate the channel occupancy of the first positioning SRS resource and directly transmit the next positioning SRS resource without sensing. However, if the channel access operation is performed before each positioning SRS resource transmission, the UE needs to sense frequently and the failure probability of channel occupancy is high. To reduce the number of channel access operations and improve the success probability of channel occupancy, the UE can configure multiple candidate COTs for positioning SRS transmission in each positioning SRS transmission gap. Thus, in addition to the above configuration for each positioning SRS transmission gap, the configuration of the positioning SRS transmission gap can also include the number of candidate COTs and the candidate COT configuration. The candidate COT can be configured by the LMF / higher layer of the gNB / UE (e.g., the RRC of the gNB, the MAC CE of the gNB). The candidate COTs in the positioning SRS transmission gap can be periodic or aperiodic.

[0315] When the candidate COT in the positioning SRS transmission gap is periodic, the configuration of the candidate COT includes at least the following:

[0316] ■Candidate COT ID;

[0317] ■ Candidate COT length;

[0318] ■ Candidate COT period;

[0319] ■ Offset of the first candidate COT relative to the start time of the positioning SRS transmission gap.

[0320] If the candidate COT within the positioning SRS transmission gap is aperiodic, the configuration of the candidate COT shall include at least:

[0321] ■ Candidate COT ID;

[0322] ■ Candidate COT length;

[0323] ■ Offset of the candidate COT relative to the start time of the positioning SRS transmission gap.

[0324] The candidate COT can be configured according to the positioning SRS transmission gap. That is, for different v transmission gaps, the configuration of the candidate COT is different. Alternatively, the candidate COT can also be configured according to the TRP. That is, if it is desired that the same gNB receives and measures the positioning SRS transmission, the candidate COT can be configured to be the same. Alternatively, the candidate COT can also be configured according to the UE. That is, for different UEs, the candidate COT can be configured differently.

[0325] For the positioning SRS resource, the UE can determine which candidate COT the positioning SRS resource transmission time belongs to based on the configuration of the positioning SRS. Then, the UE performs channel access before the candidate COT to which the positioning SRS resource transmission time belongs. One or more of the following channel access procedures can be applied before the candidate COT:

[0326] ■ The UE senses at least one sensing time slot before transmitting the positioning SRS resource, where the sensing time slot is 9 microseconds. If at least one sensing time slot is sensed to be idle, the UE can transmit the positioning SRS resource after the sensing time slot.

[0327] ■ Alternatively, the UE senses at least the sensing interval before transmitting the positioning SRS resource, where the sensing interval is 25 microseconds. The sensing interval includes two sensing time slots, where the sensing time slot is 9 microseconds, and where one sensing time slot is at the start of the sensing interval and the other sensing time slot is at the end of the sensing interval. If both sensing time slots of the sensing interval are sensed to be idle, the UE transmits the positioning SRS resource after the sensing interval.

[0328] ■ Alternatively, the UE senses for at least a sensing duration before transmitting the positioning SRS resource, where the sensing duration is 16 microseconds. The sensing duration includes a sensing time slot, where the sensing time slot is 9 microseconds and at the end of the sensing duration. If, within the sensing duration, a total of at least 5 microseconds are sensed as idle, where at least 4 microseconds occur within the sensing time slot, then the UE transmits the positioning SRS resource after the sensing duration.

[0329] If a candidate COT is initiated, the UE is capable of transmitting the positioning SRS starting at the beginning of the candidate COT. If the UE does not transmit the positioning SRS transmission at the beginning of the initiated candidate COT, and the duration between the beginning of the initiated candidate COT and the positioning SRS transmission time is at most one sensing time slot / 16 microseconds, then the UE can directly transmit the positioning SRS at the positioning SRS transmission time. If the UE does not transmit the positioning SRS transmission at the beginning of the initiated candidate COT, and the duration between the beginning of the initiated candidate COT and the positioning SRS transmission time is greater than one sensing time slot / 16 microseconds, then the UE needs to sense at least one sensing time slot before transmitting the positioning SRS. If at least one sensing time slot is sensed as idle, then the UE can transmit the positioning SRS after the sensing time slot.

[0330] In the initiated candidate COT, the UE can transmit multiple positioning SRS resources. If there is a gap between the current positioning SRS resource and the previous positioning SRS resource, then the Type 2 channel access procedure can be used for the current positioning SRS resource. Alternatively, if the gap between the current positioning SRS resource and the previous positioning SRS resource is at most one sensing time slot / 16 microseconds, then the current positioning SRS resource can be directly transmitted without sensing. If the interval between the current positioning SRS resource and the previous positioning SRS resource is greater than one sensing time slot / 16 microseconds, then the UE may need to sense at least one sensing time slot before the current positioning SRS resource. If at least one sensing time slot is sensed as idle, then the UE can transmit the current positioning SRS after the sensing time slot. Alternatively, the UE can transmit multiple positioning SRS resources during the initiated candidate COT without sensing.

[0331] For locating SRS resources, the UE may initiate one or more candidate channel occupations starting at the first candidate COT. If the candidate channel occupation fails, the next candidate COT may be initiated. The UE stops performing the channel access procedure for the remaining candidate COTs until one or more candidate COTs are successfully initiated. Alternatively, the UE may initiate one or more candidate channel occupations starting at the candidate COT to which the SRS transmission time for positioning belongs. If the candidate channel occupation fails, the next candidate COT may be initiated. The UE stops the channel access procedure for the remaining candidate COTs until one or more candidate COTs are successfully initiated or the number of initiated candidate COTs reaches the maximum number of candidate COTs. The number of candidate COTs that the UE needs to successfully initiate may be determined by the UE.

[0332] Alternatively, within the SRS transmission gap for positioning, the UE may initiate channel occupation based on the Type 1 channel access procedure. The LMF / gNB / UE may determine / configure the maximum number of candidate COTs initiated using the Type 1 channel access procedure, where the total duration of all candidate COTs shall not be greater than the length of the SRS transmission gap for positioning. For SRS resource transmission for positioning, the UE may initiate a candidate COT based on the Type 1 channel access procedure using the CAPC value corresponding to the SRS resource transmission for positioning. If the candidate channel occupation fails, the next candidate COT may be initiated based on the Type 1 channel access procedure using the CAPC value corresponding to the SRS resource transmission for positioning. The UE may stop the channel access procedure for the remaining candidate COTs using the CAPC value corresponding to the SRS resource transmission for positioning until one or more candidate COTs are successfully initiated or the number of initiated candidate COTs reaches the maximum number of candidate COTs. The number of candidate COTs that the UE needs to successfully initiate may be determined by the UE. If the time gap between two SRS resources for positioning is at most one sensing time slot / 16 microseconds, the UE may initiate COT for the first SRS resource for positioning and directly transmit the next SRS resource without performing sensing. If the time gap between two SRS resources for positioning is greater than one sensing time slot / 16 microseconds, the UE may need to initiate COT for the second SRS resource for positioning based on the Type 1 channel access procedure using the CAPC value corresponding to the second SRS resource transmission for positioning. Alternatively, if the time gap between two SRS resources for positioning is greater than one sensing time slot / 16 microseconds and if the UE has initiated COT for the first SRS resource for positioning, the UE may sense at least one sensing time slot before the second SRS resource for positioning.

[0333] Alternatively, the configuration of each positioning SRS transmission gap may further include the repetition information of the positioning SRS transmission gap. The repetition information of the positioning SRS transmission gap includes at least: the repetition factor and the time gap between two repetitions of the positioning SRS transmission gap. When repeating the positioning SRS transmission gap, one or more COTs may be initiated to transmit the positioning SRS resource using the Type 1 / 2 channel access procedure. For positioning SRS transmission, the UE may initiate a COT starting from the first repetition of the positioning SRS transmission gap. If the COT initiated in the first repetition of the positioning SRS transmission gap fails, the UE may initiate a COT in the next repetition of the positioning SRS transmission gap until one or more COTs / repetitions are successfully occupied or the number of repetitions of initiating the COT reaches the maximum number of repetitions of the positioning SRS transmission gap. Alternatively, for the positioning SRS resource, the UE may determine which repetition of the positioning SRS transmission gap the positioning SRS resource transmission time belongs to based on the configuration of the positioning SRS. Then, the UE initiates a COT for positioning SRS resource transmission within the repetition of the positioning SRS transmission gap to which the positioning SRS resource transmission time belongs.

[0334] Embodiment 13: DL-PRS transmission in multiple channels.

[0335] To obtain satisfactory positioning accuracy, the bandwidth of DL-PRS is usually large. In the unlicensed band, DL-PRS transmission may require multiple channels. Since the channel access operation is performed per channel, some channels may be successfully accessed while some channels may not be accessed. Figure 12 A schematic diagram of multi-channel access is shown. Thus, how to transmit DL-PRS in multiple channels in the unlicensed band is a problem. In this embodiment, some configurations and rules are provided for DL-PRS transmission in multiple channels. Figure 12 A schematic diagram of multi-channel access is provided.

[0336] If some channels are successfully accessed while some channels are not successfully accessed, when some conditions are met, the gNB may transmit DL-PRS in the accessed channels. The LMF may configure the channel mode. When the mode of the accessed channel meets the channel mode configured by the LMF, DL-PRS may be transmitted in the accessed channel. To reduce the detection complexity, the UE may detect DL-PRS in the frequency domain according to the channel mode configured by the LMF.

[0337] The rules that the gNB needs to meet for DL-PRS transmission in multiple channels may be one or more of the following:

[0338] ■ If the successfully accessed channels are continuous and the number of continuous accessed channels is not less than the threshold, the gNB may transmit DL-PRS in the continuous accessed channels. Otherwise, the gNB may not transmit DL-PRS in any channels. The threshold may be configured / determined by the LMF / gNB.

[0339] ■ When it is ensured that a determined channel can be successfully accessed and several channels continuous with the determined channel are also successfully accessed, if the total number of the determined channel and its continuous accessed channels is not less than the threshold, the gNB may transmit DL-PRS in the determined channel and its continuous accessed channels. Otherwise, the gNB does not transmit DL-PRS in any channels. This determined channel and the threshold may be configured / determined by the LMF / gNB. This determined channel may be associated with one or more of the following: RB set ID, the starting position of the RB set in the frequency domain, or the bandwidth of the RB set.

[0340] If the number of successfully accessed channels is not less than the threshold, the gNB may transmit DL-PRS in the accessed channels. Otherwise, the gNB does not transmit DL-PRS in any channels. The threshold may be configured / determined by the LMF / gNB.

[0341] The above solutions can be applied to the DL-PRS transmission in multiple channels with or without guard bands. The serving gNB may transmit the information of the accessed channels for DL-PRS transmission to the UE through the downlink control information DCI. Alternatively, the serving gNB may transmit the information of the accessed channels for DL-PRS transmission to the LMF via NRPPa, and the LMF may transmit these accessed channel information to the UE via LPP. The information of the accessed channels for transmitting DL-PRS includes at least one or more of the following: RB set ID, the starting position of the RB set in the frequency domain, or the bandwidth of the RB set.

[0342] In addition, the serving gNB may transmit the channel information for the DL-PRS transmission of the neighboring gNB to the UE through DCI. Alternatively, the serving gNB may transmit the channel information for the DL-PRS transmission of the neighboring gNB to the LMF through NRPPa, and the LMF transmits the channel information for the DL-PRS transmission of the neighboring gNB to the UE through LPP.

[0343] For positioning SRS transmission, the bandwidth of the positioning SRS is also large. In the unlicensed band, positioning SRS transmission usually requires multiple channels. Since the channel access operation is performed per channel, some channels can be successfully accessed while some channels may not be accessed. The solution for positioning SRS transmission in multiple channels is similar to the DL-PRS transmission in multiple channels.

[0344] If some channel accesses are successful while some are not, the UE may transmit DL-PRS in the access channel when some conditions are met. The LMF may configure the channel mode. When the access channel mode meets the channel mode configured by the LMF, positioning SRS may be transmitted in the access channel. The LMF may transmit the channel mode to the gNB, and the gNB may detect the positioning SRS in the frequency domain according to the channel mode configured by the LMF.

[0345] The rules that the UE needs to meet for positioning SRS transmission in multiple channels may be at least one or more of the following:

[0346] ■ If the successfully accessed channels are continuous and the number of continuous accessed channels is not less than the threshold, the UE may transmit positioning SRS in the continuous accessed channels. Otherwise, the UE may not transmit positioning SRS in any channel. The threshold may be configured / determined by the LMF / gNB / UE.

[0347] ■ When it is ensured that a certain channel can be successfully accessed and several channels continuous with the certain channel are also successfully accessed, if the total number of the certain channel and its continuous accessed channels is not less than the threshold, the UE may transmit positioning SRS in the certain channel and its continuous accessed channels. Otherwise, the UE may not transmit positioning SRS in any channel. This certain channel and the threshold may be configured / determined by the LMF / gNB / UE. This certain channel may be associated with one or more of the following: RB set ID, the starting position of the RB set in the frequency domain, or the bandwidth of the RB set.

[0348] The solution for positioning SRS transmission in multiple channels may be applied to multiple channels with or without guard bands. The UE may transmit the access channel information for positioning SRS transmission to its serving gNB through UCI. And the UE may transmit the access channel information for positioning SRS transmission to the LMF via LPP, and the LMF may transmit these access channel information to the neighboring gNB via NRPPa. The access channel information for transmitting DL-PRS includes at least one or more of the following: RB set ID, the starting position of the RB set in the frequency domain, and RB set bandwidth. Alternatively, the UE may transmit the access channel information for positioning SRS transmission to the LMF via LPP, and the LMF may transmit these access channel information to the serving gNB and the neighboring gNB via NRPPa.

[0349] Embodiment 14: DL-PRS transmission of multiple gNBs in multiple channels.

[0350] In Embodiment 11, rules and configurations are provided for DL-PRS transmission in multiple channels. If the gNB accesses multiple channels that meet the DL-PRS transmission conditions, these multiple access channels can be shared with other gNBs. Multiple gNBs can use comb-based multiplexing to transmit DL-PRS in the channels. Therefore, the gNB that initiates COT in multiple channels can inform other gNBs of the access channel information and its DL-PRS configuration in the following ways:

[0351] ■ The Xn interface.

[0352] ■ Alternatively, it is completed by the LMF through NRPPa. That is, the initiating gNB transmits the access channel information to the LMF via NRPPa, and then the LMF transmits the access channel information and the DL-PRS configuration of the initiating gNB to other gNBs via NRPPa.

[0353] The access channel information and the DL-PRS configuration of the initiating gNB include one or more of the following:

[0354] ■ The ID of the access RB set;

[0355] ■ The starting position of the access RB set in the frequency domain;

[0356] ■ The bandwidth of each access RB set;

[0357] ■ The comb size of the DL-PRS resources of the initiating gNB;

[0358] ■ The comb offset of the DL-PRS resources of the initiating gNB.

[0359] Embodiment 15: Hopping of DL-PRS / Location SRS transmission across COTs.

[0360] In the unlicensed band, DL-PRS / Location SRS can be transmitted in multiple channels. Since some channels are available while some are not, the DL-PRS / Location SRS resources may not be completely transmitted, and the bandwidth for DL-PRS / Location SRS transmission in the COT is not ideal. To solve this problem, hopping of DL-PRS / Location SRS across COTs is introduced in this embodiment.

[0361] For DL-PRS / Location SRS transmission, after the gNB / UE executes the channel occupancy procedure in multiple channels for the COT, the gNB / UE can transmit the channel occupancy information for the DL-PRS / Location SRS resources to the LMF via NRPPa / LPP. The channel occupancy information for the DL-PRS / Location SRS resources in the COT includes at least one or more of the following:

[0362] ■ COT ID;

[0363] ■ COT length;

[0364] ■ COT start time;

[0365] ■ RB set ID occupied by DL-PRS / Location SRS within COT;

[0366] ■ Starting position of the RB set within COT in the frequency domain;

[0367] ■ Bandwidth of each RB set within COT.

[0368] Figure 13 Channel occupancy in multiple RB sets in multiple COTs is shown. The LMF determines whether to perform frequency hopping across COTs for DL-PRS / Location SRS reception. The indicator can be configured by the LMF and transmitted to the UE / gNB via LPP / NRPPa. The indicator indicates whether the UE / gNB receives DL-PRS / Location SRS with frequency hopping across COTs, and it is 1 bit. The indicator for DL-PRS frequency hopping can be provided by the LMF to the UE in the auxiliary data. To assist the UE / gNB in receiving DL-PRS / Location SRS and performing frequency hopping, the LMF can provide information about the COTs for the UE / gNB to perform frequency hopping. The information about the COTs includes at least one or more of the following:

[0369] ■ COT ID;

[0370] ■ COT length;

[0371] ■ COT start time;

[0372] ■ RB set ID occupied by DL-PRS / Location SRS within COT;

[0373] ■ Starting position of the RB set occupied by DL-PRS / Location SRS within COT in the frequency domain;

[0374] ■ Bandwidth of each RB set occupied by DL-PRS / Location SRS.

[0375] When the UE / gNB receives the frequency hopping indicator and COT information, if the indicator indicates that frequency hopping is performed, the UE / gNB can measure the DL-PRS / Location SRS and obtain measurements based on the multi-hop of DL-PRS / Location SRS in multiple COTs and the corresponding RB sets. Figure 14 Channel occupancy in multiple RB sets in multiple COTs is shown.

[0376] Embodiment 16: DL-PRS reception of UE.

[0377] If the gNB uses the Type 1 channel access procedure to initiate channel occupancy for DL-PRS transmission, the sensing duration of the access channel is random, and then the DL-PRS transmission time is also random. How to receive and measure DL-PRS in the unlicensed band is a problem. One solution is for the UE to continuously detect DL-PRS. However, if the UE continuously detects DL-PRS, the power consumption is very high. In this embodiment, two search space set groups are introduced for DL-PRS reception.

[0378] For DL-PRS reception, two search space set groups can be configured by the higher layer of the LMF / gNB. The UE can detect DCI outside the COT in one search space set group, and can detect DL-PRS within the COT in another search space set group. The search frequencies of the two search space set groups are different. The search space set group switching is indicated by DCI. The DCI at least includes: the COT duration and the search space set group switching indicator. The UE can use the search space set group to detect DCI, and when the UE detects DCI, it switches to another search space set group to detect DL-PRS within the COT duration. The start time of the COT is the time slot in which DCI is detected. The search space set group for searching DL-PRS within the COT is associated with the DL-PRS resource period. If there are multiple DL-PRS resources within the COT, the search space set group for searching DL-PRS within the COT is related to the common factor of the multiple DL-PRS resource periods. Figure 14 It shows that the UE uses two search space set groups to detect DCI and DL-PRS. Alternatively, the higher layer of the LMF / gNB can configure one search space set group for DL-PRS reception. This search space set group is used to detect DCI outside the COT. The DCI at least includes the COT duration. When the UE detects DCI, the UE continuously detects DL-PRS within the COT. Figure 14 It shows the UE reception with two search space set groups.

[0379] If the gNB transmits DL-PRS transmission that does not include DCI, the search window can be configured / pre-configured by the higher layer of the LMF / gNB. The search window can be periodic or aperiodic. If the search window is periodic, the configuration of the search window includes at least one or more of the following:

[0380] ■ Search window length;

[0381] ■ Search window period;

[0382] ■ The start time of the first period of the search window / the offset of the first period of the search window relative to the reference time

[0383] ■ offset;

[0384] ■Reference time, for example, SFN0 / DFN0.

[0385] If the search window is aperiodic, the configuration of the search window may include at least one or more of the following:

[0386] ■Search window length;

[0387] ■Search window start time / offset of the search window relative to the reference time;

[0388] ■Reference time, for example, SFN0 / DFN0.

[0389] If the gNB transmission does not include a DL-PRS transmission with DCI, the UE considers that the gNB initiates one or more COTs within the search window and transmits the DL-PRS within the search window. Thus, the UE can receive the DL-PRS in a set of search spaces outside the search window and can also receive the DL-PRS in another set of search spaces within the search window. The set of search spaces can be configured by the higher layer of the LMF / gNB. The set of search spaces for receiving the DL-PRS within the search window is associated with the period of the DL-PRS resource. If there are multiple DL-PRS resources within the search window, the set of search spaces for receiving the DL-PRS within the search window is related to the greatest common divisor of the periods of the multiple DL-PRS resources. Alternatively, the UE can only receive the DL-PRS in the set of search spaces within the search window and does not detect and receive the DL-PRS outside the search window. The set of search spaces can be configured by the higher layer of the LMF / gNB. Alternatively, the UE can continuously receive the DL-PRS within the search window and does not detect and receive the DL-PRS outside the search window.

[0390] If the UE does not receive the first symbol of the DL-PRS resource, the UE may no longer receive the other symbols of the DL-PRS resource. Alternatively, if the number of symbols of the DL-PRS resource not received by the UE is greater than or equal to a threshold, the UE may no longer receive the other symbols of the DL-PRS resource. The threshold can be configured by the higher layer of the LMF / gNB. The threshold can be related to the number of symbols of the DL-PRS resource and the comb size of the DL-PRS resource. Figure 15 A schematic diagram of DL-PRS reception is shown, where some DL-PRS symbols are missed.

[0391] It should be understood that one or more features from the above embodiments do not exclude a particular embodiment, but can be combined in any way (e.g., in any priority and / or order, simultaneously or otherwise).

[0392] Figure 16FIG. 1600 is a flowchart of a method for transmitting and receiving positioning reference signals in a New Radio (NR) unlicensed band. Method 1600 may be implemented using any one or more of the components and devices detailed herein in conjunction with Figures 1 to 15 In general, in some embodiments, method 1600 may be performed by a first wireless communication entity (e.g., BS 202 or UE 204) and / or a second wireless communication entity (e.g., BS 202 or UE 204). Depending on the embodiment, additional, fewer, or different operations may be performed in method 1600. At least one aspect of the operations relates to a system, method, apparatus, or computer-readable medium.

[0393] The first wireless communication entity may transmit a positioning reference signal on an unlicensed band to the second wireless communication entity based on one or more channel occupancy parameters associated with the unlicensed band. The first wireless communication entity may identify one or more channel occupancy parameters based on a channel access priority class (CAPC) table configured for data transmission reuse.

[0394] In some embodiments, the first wireless communication entity may identify one or more channel occupancy parameters based on a preconfigured CAPC table. The configuration of the preconfigured CAPC table is associated with the configuration of the positioning reference signal. The one or more channel occupancy parameters may include at least one of the following: a CAPC value, a minimum contention window size, a maximum contention window size, an allowed contention window size, or a maximum channel occupancy time (COT).

[0395] In some embodiments, the configuration of the positioning reference signal as a downlink positioning reference signal (DL-PRS) may include at least one of the following: the priority of the DL-PRS, the transmission duration of the DL-PRS, the repetition factor of the DL-PRS, the time gap between two repetitions of the DL-PRS, or the period of the DL-PRS. The configuration of the positioning reference signal as an uplink sounding reference signal (UL-SRS) may include at least one of the following: the priority of the UL-SRS, the transmission duration of the UL-SRS, the number of symbols of the UL-SRS, or the period of the UL-SRS.

[0396] In some embodiments, the CAPC value may be indicated by an information element (IE). The CAPC value may be determined based on the configuration of the positioning reference signal. The CAPC value for transmitting the positioning reference signal as a DL-PRS may be configured by a core network entity or a higher layer of the first wireless communication entity. The CAPC value for transmitting the positioning reference signal as a UL-SRS may be configured by a core network entity or a higher layer of the first wireless communication entity or a higher layer of the second wireless communication entity.

[0397] In some embodiments, the CAPC value for transmitting a positioning reference signal as a DL-PRS may be configured according to a Physical Frequency Layer (PFL), a DL-PRS resource set, or a DL-PRS resource. The CAPC value for transmitting a positioning reference signal as a UL-SRS may be configured according to a Bandwidth Part (BWP), a UL-SRS resource set, or a UL-SRS resource. The second wireless communication entity may be in the RRC_CONNECTED state. The CAPC value for transmitting a positioning reference signal as a UL-SRS may be configured according to a UL-SRS resource set or a UL-SRS resource, where the second wireless communication entity is in the RRC_INACTIVE state.

[0398] In some embodiments, when at least one of the following conditions is met, the first wireless communication entity may use a Type 2A channel access procedure to initiate a channel occupancy procedure: (a) the transmission duration of the DL-PRS is at most 1 ms, and the transmission duty cycle of the DL-PRS is at most 1 / 20; (b) the CAPC value configured for the DL-PRS is less than or equal to a CAPC threshold; (c) the priority value configured for the DL-PRS is less than a priority threshold; or (d) the DL-PRS is transmitted in a broadcast manner. When the following condition is met, the first wireless communication entity may transmit a positioning reference signal in a shared channel occupancy procedure: the CAPC value configured for the positioning reference signal is less than or equal to the CAPC value for initiating the shared channel occupancy procedure.

[0399] In some embodiments, the period of the positioning reference signal may be associated with the period of a semi-static channel occupancy procedure. The association may include at least one of the following: the period of the positioning reference signal may be equal to the period of the semi-static channel occupancy procedure, or the period of the positioning reference signal may be an integer multiple of the period of the semi-static occupancy procedure. The configuration of the semi-static channel occupancy procedure for the positioning reference signal may not be limited to the number of radio frames. The configuration of the semi-static channel occupancy procedure may include at least one of the following: the period of the semi-static channel occupancy procedure, or the time offset of the period of the semi-static channel occupancy procedure relative to a reference time.

[0400] In some embodiments, the first wireless communication entity may report information about a semi-static channel occupancy procedure initiated by the first wireless communication entity to a core network entity. The information may include at least one of the following: the period of the semi-static channel occupancy procedure, the time of the idle duration, or the COT length. The core network entity may recommend transmission resources for a positioning reference signal as a DL-PRS to the first wireless communication entity. The core network entity may recommend transmission resources for a positioning reference signal as a UL-SRS to a serving base station.

[0401] In some embodiments, in response to determining that the time domain resources configured for positioning reference signals are within the COT, the first wireless communication entity may transmit the positioning reference signals. In response to determining that the time domain resources configured for positioning reference signals are not within the COT, the first wireless communication entity may stop transmitting the positioning reference signals.

[0402] In some embodiments, if only some symbols configured for positioning reference signals are within the COT, the first wireless communication entity may transmit the positioning reference signals based on some rules. The first wireless communication entity may send the channel occupancy window related information associated with the positioning reference signals to the third wireless communication entity. The COT of the positioning reference signals may be initiated in advance by the first wireless communication entity or the second wireless communication entity. If the COT is initiated based on the dynamic channel access procedure, the channel occupancy window related information may include at least one of the following: the CAPC value for initiating the COT, the COT duration, the COT start time, the channel occupancy window length, or the channel occupancy window start time.

[0403] In some embodiments, if the COT is initiated based on the semi-static channel occupancy, the channel occupancy window related information may include at least one of the following: the semi-static channel occupancy period, the maximum COT of the semi-static channel occupancy period, the start time of the semi-static channel occupancy period, the channel occupancy window length, or the channel occupancy window start time. The channel occupancy window length may not be greater than the maximum COT. The channel occupancy window length may not be greater than the maximum COT of the semi-static channel occupancy period. The third wireless communication entity may be determined by the first wireless communication entity or the second wireless communication entity or the core network entity.

[0404] In some embodiments, the PFL configured for transmitting the positioning reference signals may include an integer number of resource block (RB) sets. The first wireless communication entity may perform the channel access procedure according to the RB sets. A guard band may or may not be configured between two consecutive RB sets. An indicator of the multi-channel access procedure type may be included in the configuration of the PFL, or the configuration of the positioning service, or the configuration of the positioning reference signal resource set, or the configuration of the positioning reference signal resources.

[0405] In some embodiments, one or more transmission gaps configured for transmitting the positioning reference signals as DL-PRS may be configured by the higher layer of the first wireless communication entity. One or more transmission gaps configured for transmitting the positioning reference signals as UL-SRS may be configured by the core network entity, the higher layer of the first wireless communication entity, or the higher layer of the second wireless communication entity. Each of the one or more transmission gaps may be associated with a transmission gap ID. The configuration of the one or more transmission gaps may include at least one of the following: the transmission gap ID, the length of the one or more transmission gaps, the period of the one or more transmission gaps, the reference point in the time domain, or the offset of the one or more transmission gaps relative to the reference point in the time domain.

[0406] In some embodiments, the first wireless communication entity may perform a channel access procedure before transmitting on each positioning reference signal resource in a transmission gap. If the positioning reference signal is a DL-PRS, multiple candidate COTs for transmitting the positioning reference signal may be configured by the higher layer of the first wireless communication entity in the transmission gap. If the positioning reference signal is a UL-SRS, multiple candidate COTs for transmitting the positioning reference signal may be configured by a core network entity, or the higher layer of the first wireless communication entity, or the higher layer of the serving base station in the transmission gap. The configuration of the transmission gap may also include the number of candidate COTs and the configuration of the candidate COTs. The candidate COTs in the transmission gap may be periodic or aperiodic. If the candidate COT is periodic, the configuration of one candidate COT may be at least one of the following: candidate COT ID, candidate COT length, candidate COT period, or the offset of the candidate COT relative to the start time of the transmission gap. If the candidate COT is aperiodic, the configuration of one candidate COT may be at least one of the following: candidate COT ID, candidate COT length, or the offset of the candidate COT relative to the start time of the transmission gap. The candidate COTs in the transmission gap for transmitting the positioning reference signal as a DL-PRS may be configured by transmission gap, or PFL, or serving cell, or UE. The candidate COTs in the transmission gap for transmitting the positioning reference signal as a UL-SRS may be configured by transmission gap, or UE, or TRP.

[0407] In some embodiments, the first wireless communication entity may perform a candidate COT channel access procedure. The configuration of the transmission gap may also include the maximum number of candidate COTs initiated using the Type 1 channel access procedure. The total duration of all candidate COTs initiated using the Type 1 channel access procedure may not be greater than the length of the transmission gap. The configuration of the transmission gap also includes the repetition information of the transmission gap. The repetition information of the transmission gap may be at least one of the following: the repetition factor of the transmission gap or the time gap between two repetitions.

[0408] In some embodiments, when the following conditions are met: the channel is continuous and the number of continuous channels is not less than a threshold, the first wireless communication entity may transmit a positioning reference signal on multiple successfully accessed channels. When the following conditions are met: the successfully accessed channel corresponds to a channel mode, the first wireless communication entity may transmit the positioning reference signal in the channel mode. The channel mode may be configured by a core network entity. The second wireless communication entity may receive the positioning reference signal according to the channel mode.

[0409] In some embodiments, the transmission of the positioning reference signal and the transmission of another positioning reference signal sent by another first wireless communication entity may be configured in a comb-based multiplexing manner. The first wireless communication entity may send access channel information and the configuration of the positioning reference signal to a third wireless communication entity. The access channel information may be at least one of the following: the ID of the access RB set, the starting position of the access RB set in the frequency domain, or the bandwidth of each access RB set. The configuration of the positioning reference signal may be at least one of the following: the comb size of the positioning reference signal; or the comb offset of the positioning reference signal.

[0410] In some embodiments, one or more channel occupancy parameters may be sent by the first or second communication entity to the core network entity. The one or more channel occupancy parameters may be at least one of the following: COT ID; COT length; COT start time; the RB set ID occupied by the positioning reference signal within the COT; the starting position of the RB set in the frequency domain within the COT; or the bandwidth of each RB set within the COT.

[0411] In some embodiments, the second communication entity may receive the positioning reference signal as DL-PRS according to the reception configuration configured by the higher layer of the first communication entity or the core network entity. The reception configuration may include a first search space set group and a second search space set group corresponding to the COT. The first search space set group may be configured to detect DCI outside the COT. The second search space set group may be configured to receive the DL-PRS within the COT. The second search space set group may be associated with the positioning reference signal resource period.

[0412] In some embodiments, the reception configuration may include a search window, where the search window is periodic or aperiodic. If the search window is periodic, the configuration of the search window may be at least one of the following: search window length, search window period, or the start time of the first period of the search window. If the search window is aperiodic, the configuration of the search window may be at least one of the following: search window length, or search window period. The reception configuration may include a search space set group corresponding to the search window. The search space set group may be configured to receive the DL-PRS within the search window. The second communication entity may continuously receive the positioning reference signal as DL-PRS within the search window.

[0413] While the above has described different embodiments of the present disclosure, it should be understood that it is presented by way of example only and not limitation. Similarly, different figures may depict exemplary architectures or configurations provided to enable those of ordinary skill in the art to understand the exemplary features and functions of the present disclosure. However, such persons will understand that the solution is not limited to the illustrated exemplary architectures or configurations, but rather various alternative architectures and configurations may be used to implement it. Additionally, as those of ordinary skill in the art will understand, one or more features of one embodiment may be combined with one or more features of another embodiment described herein. Accordingly, the breadth and scope of the present disclosure should not be limited by any of the above exemplary embodiments.

[0414] It should also be understood that any reference in the present disclosure to elements by names such as "first", "second", etc. generally does not limit the number or order of those elements. Instead, these names may be used in the present disclosure as a means of distinguishing between two or more elements or instances of an element. Thus, the reference to a first element and a second element does not mean that only two elements may be employed, or that the first element must precede the second element in some manner.

[0415] Additionally, those skilled in the art will understand that any of a variety of different technologies and techniques may be used to represent information and signals. For example, the data, instructions, commands, information, signals, bits, and symbols that may be referenced in the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0416] Those skilled in the art will further appreciate that any of the different exemplary logic blocks, modules, processors, devices, circuits, methods, and functions described in connection with the embodiments of the present disclosure may be implemented by electronic hardware (e.g., digital implementation, analog implementation, or a combination of both), firmware, different forms of programs incorporating instructions or design code (for convenience, which may be referred to in the present disclosure as "software" or "software modules"), or any combination of these technologies. To clearly illustrate this interchangeability of hardware, firmware, and software, the above has described the different exemplary components, blocks, modules, circuits, and steps in terms of their functional aspects. Whether the functions are implemented as hardware, firmware, or software, or a combination of these solutions, depends on the particular application and the design constraints imposed on the overall system. Those skilled in the art may implement the described functions in different ways for each particular application, but such implementation decisions will not result in departing from the scope of the present disclosure.

[0417] In addition, those skilled in the art will understand that the various exemplary logic blocks, modules, devices, components, and circuits described in this disclosure may be implemented within 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 any combination of other programmable logic devices. The logic blocks, modules, and circuits may also include antennas and / or transceivers to communicate with various components within a network or within a device. The general-purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other suitable configuration that performs the functions described in this disclosure.

[0418] If implemented in software, the functions may be stored as one or more instructions or code on a computer-readable medium. Accordingly, the steps of the methods or algorithms of this disclosure may be implemented as software stored on a computer-readable medium. The computer-readable medium includes both computer storage media and communication media, where the communication media includes any medium that can transfer a computer program or code from one place to another. The storage media may be any available medium accessible by a computer. By way of example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage devices, or any other medium that can be used to store the desired program code in the form of instructions or data structures and that is accessible by a computer.

[0419] In this disclosure, the term "module" refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described in this disclosure. Additionally, for purposes of discussion, different modules are described as discrete modules; however, as will be apparent to those of ordinary skill in the art, two or more modules may be combined to form a single module that performs the associated functions according to embodiments of this disclosure.

[0420] Furthermore, a memory or other storage, as well as communication components, may be employed in embodiments of this disclosure. It should be understood that, for clarity, the above description has described embodiments of this disclosure with reference to different functional units and processors. However, it will be apparent that any suitable functional allocation may be made between different functional units, processing logic elements, or domains without detracting from the effectiveness of this disclosure. For example, functions shown to be performed by separate processing logic elements or controllers may be performed by the same processing logic element or controller. Accordingly, the reference to a particular functional unit is only a reference to a means suitable for implementing the described function and does not indicate a strict logical structure or physical organization.

[0421] Various modifications to the embodiments described in this disclosure will be apparent to those skilled in the art, and the general principles defined in this disclosure can be applied to other embodiments without departing from the scope of the disclosure. Thus, this disclosure is not intended to be limited to the embodiments shown in this disclosure, but rather to embrace the widest scope consistent with the novel features and principles of this disclosure, as set forth in the following claims.

Claims

1. A wireless communication method, comprising: A first wireless communication entity transmits a positioning reference signal on the unlicensed band to a second wireless communication entity based on one or more channel occupancy parameters associated with the unlicensed band.

2. The wireless communication method according to claim 1, further comprising: The first wireless communication entity identifies the one or more channel occupancy parameters based on a channel access priority class (CAPC) table reused for data transmission.

3. The wireless communication method according to claim 1, further comprising: The first wireless communication entity identifies the one or more channel occupancy parameters based on a preconfigured CAPC table; wherein the configuration of the preconfigured CAPC table is associated with the configuration of the positioning reference signal.

4. The wireless communication method according to any one of claims 2 to 3, wherein, The one or more channel occupancy parameters include at least one of the following: CAPC value, minimum contention window size, maximum contention window size, allowed contention window size, or maximum channel occupancy time (COT).

5. The wireless communication method according to claim 3, wherein, The configuration of the positioning reference signal as DL-PRS includes at least one of the following: the priority of the DL-PRS, the transmission duration of the DL-PRS, the repetition factor of the DL-PRS, the time gap between two repetitions of the DL-PRS, or the period of the DL-PRS.

6. The wireless communication method according to claim 3, wherein, The configuration of the positioning reference signal as UL-SRS includes at least one of the following: the priority of the UL-SRS, the transmission duration of the UL-SRS, the number of symbols of the UL-SRS, or the period of the UL-SRS.

7. The wireless communication method according to claim 4, wherein, The CAPC value is indicated by an information element (IE).

8. The wireless communication method according to claim 4, wherein, The CAPC value is determined based on the configuration of the positioning reference signal.

9. The wireless communication method according to claim 4, Among them, The CAPC value for transmitting the positioning reference signal as DL-PRS is configured by a core network entity or a higher layer of the first wireless communication entity, wherein the CAPC value for transmitting the positioning reference signal as UL-SRS is configured by the core network entity or a higher layer of the first wireless communication entity or a higher layer of the second wireless communication entity.

10. The wireless communication method according to claim 4, wherein, The CAPC value for transmitting the positioning reference signal as DL-PRS is configured according to a physical frequency layer (PFL), a DL-PRS resource set, or a DL-PRS resource.

11. The wireless communication method according to claim 4, wherein, The CAPC value for transmitting the positioning reference signal as UL-SRS is configured according to a bandwidth part (BWP), a UL-SRS resource set, or a UL-SRS resource, wherein the second wireless communication entity is in the RRC_CONNECTED state.

12. The wireless communication method according to claim 4, wherein, The CAPC value for transmitting the positioning reference signal as UL-SRS is configured according to a UL-SRS resource set or a UL-SRS resource, and wherein the second wireless communication entity is in the RRC_INACTIVE state.

13. The wireless communication method according to claim 1, further comprising: The first wireless communication entity initiates a channel occupancy procedure using a Type 2A channel access procedure when at least one of the following conditions is met: (a) The transmission duration of the DL-PRS is at most 1 ms, and the transmission duty cycle of the DL-PRS is at most 1 / 20; (b) The CAPC value configured for the DL-PRS is less than or equal to the CAPC threshold; (c) The priority value configured for the DL-PRS is less than the priority threshold; or (d) The DL-PRS is transmitted in broadcast mode.

14. The wireless communication method according to claim 1, further comprising: When the following conditions are met, the first wireless communication entity transmits the positioning reference signal in a shared channel occupancy procedure: The CAPC value configured for the positioning reference signal is less than or equal to the CAPC value for initiating the shared channel occupancy procedure.

15. The wireless communication method according to claim 1, wherein, The period of the positioning reference signal is associated with the period of the semi-static channel occupancy procedure.

16. The wireless communication method according to claim 15, wherein, The association includes at least one of the following: the period of the positioning reference signal is equal to the period of the semi-static channel occupancy procedure, or the period of the positioning reference signal is an integer multiple of the period of the semi-static channel occupancy procedure.

17. The wireless communication method according to claim 1, wherein, The configuration of the semi-static channel occupancy procedure for the positioning reference signal is not limited to the number of radio frames.

18. The wireless communication method according to claim 17, wherein, The configuration of the semi-static channel occupancy procedure includes at least one of the following: the period of the semi-static channel occupancy procedure, or the time offset of the period of the semi-static channel occupancy procedure relative to a reference time.

19. The wireless communication method according to claim 1, further comprising: The first wireless communication entity reports information about the semi-static channel occupancy procedure initiated by the first wireless communication entity to the core network entity; wherein the information includes at least one of the following: the period of the semi-static channel occupancy procedure, the time of the idle duration, or the COT length.

20. The wireless communication method according to claim 19, The first wireless communication entity receives a message including a recommendation of the transmission resource of the positioning reference signal as the DL-PRS from the core network entity.

21. The wireless communication method according to claim 1, further comprising: In response to determining that the time domain resource configured for the positioning reference signal is within the COT, the first wireless communication entity transmits the positioning reference signal.

22. The wireless communication method according to claim 1, further comprising: In response to determining that the time domain resource configured for the positioning reference signal is not within the COT, the first wireless communication entity stops transmitting the positioning reference signal.

23. The wireless communication method according to claim 1, further comprising: When only some of the symbols configured for the positioning reference signal are within the COT, the first wireless communication entity transmits the positioning reference signal based on some rules.

24. The wireless communication method according to claim 1, further comprising: The first wireless communication entity sends information about the channel occupancy window related to the positioning reference signal to a third wireless communication entity; Wherein, the first wireless communication entity or the second wireless communication entity pre-initiate a COT for the positioning reference signal.

25. The wireless communication method according to claim 24, wherein, In the case where the COT is initiated based on a dynamic channel access procedure, the channel occupancy window related information includes at least one of the following: the CAPC value for initiating the COT, the duration of the COT, the start time of the COT, the length of the channel occupancy window, or the start time of the channel occupancy window.

26. The wireless communication method according to claim 24, wherein, In the case where the COT is initiated based on semi-static channel occupancy, the channel occupancy window related information includes at least one of the following: the semi-static channel occupancy period, the maximum COT of the semi-static channel occupancy period, the start time of the semi-static channel occupancy period, the length of the channel occupancy window, or the start time of the channel occupancy window.

27. The wireless communication method according to claim 25, wherein, The length of the channel occupancy window is not greater than the maximum COT.

28. The wireless communication method according to claim 26, wherein, The length of the channel occupancy window is not greater than the maximum COT of the semi-static channel occupancy period.

29. The wireless communication method according to claim 24, wherein, The third wireless communication entity is determined by the first wireless communication entity or the second wireless communication entity or the core network entity.

30. The wireless communication method according to claim 1, wherein, The PFL for transmitting the positioning reference signal includes an integer number of resource block (RB) sets.

31. The wireless communication method according to claim 30, wherein, The first wireless communication entity performs a channel access procedure according to the RB set.

32. The wireless communication method according to claim 30, wherein, A guard band is configured or not configured between two consecutive RB sets.

33. The wireless communication method according to claim 30, wherein, An indicator of the multi-channel access procedure type is included in the configuration of the PFL, or the configuration of the positioning service, or the configuration of the positioning reference signal resource set, or the configuration of the positioning reference signal resource.

34. The wireless communication method according to claim 1, wherein, The higher layer of the first wireless communication entity configures one or more transmission gaps for transmitting the positioning reference signal as DL-PRS.

35. The wireless communication method according to claim 1, wherein, One or more transmission gaps for transmitting the positioning reference signal as UL-SRS are configured by the core network entity, the higher layer of the first wireless communication entity, or the higher layer of the second wireless communication entity.

36. The wireless communication method according to any one of claims 34 to 35, wherein, The one or more transmission gaps are respectively associated with a transmission gap ID.

37. The wireless communication method according to any one of claims 34 to 35, wherein, The configuration of the one or more transmission gaps includes at least one of the following: the transmission gap ID, the length of the one or more transmission gaps, the period of the one or more transmission gaps, a reference point in the time domain, or the offset of the one or more transmission gaps relative to the reference point in the time domain.

38. The wireless communication method according to claim 1, further comprising: The first wireless communication entity performs a channel access procedure before transmitting each positioning reference signal resource in the transmission gap.

39. The wireless communication method according to claim 38, wherein, In the case where the positioning reference signal is DL-PRS, in the transmission gap, the higher layer of the first wireless communication entity configures a plurality of candidate COTs for transmitting the positioning reference signal.

40. The wireless communication method according to claim 38, wherein, In the case where the positioning reference signal is UL-SRS, in the transmission gap, the core network entity or the higher layer of the first wireless communication entity or the higher layer of the serving base station configures a plurality of candidate COTs for transmitting the positioning reference signal.

41. The wireless communication method according to claim 38, wherein, The configuration of the transmission gap further includes the number of candidate COTs and the candidate COT configuration.

42. The wireless communication method according to any one of claims 38 to 41, wherein, The candidate COTs in the transmission gap are periodic or aperiodic.

43. The wireless communication method according to claim 42, wherein, In the case where the candidate COT is periodic, the configuration of one candidate COT in the candidate COTs includes at least one of the following: the candidate COT ID, the candidate COT length, the candidate COT period, or the offset of the candidate COT with respect to the start time of the transmission gap.

44. The wireless communication method according to claim 42, wherein, In the case where the candidate COT is aperiodic, the configuration of one candidate COT in the candidate COTs includes: the candidate COT ID, the candidate COT length, or the offset of the candidate COT with respect to the start time of the transmission gap.

45. The wireless communication method according to claim 42, wherein, The candidate COT for transmitting the positioning reference signal as the DL-PRS in the transmission gap can be configured according to the transmission gap, or PFL, or serving cell, or UE.

46. The wireless communication method according to claim 42, wherein, The candidate COT for transmitting the positioning reference signal as the UL-SRS in the transmission gap can be configured according to the transmission gap, or UE, or TRP.

47. The wireless communication method according to claim 1, further comprising: The first wireless communication entity performs a channel access procedure according to the candidate COT.

48. The wireless communication method according to claim 42, wherein, The configuration of the transmission gap further includes the maximum number of candidate COTs initiated using the Type 1 channel access procedure.

49. The wireless communication method according to claim 48, wherein, The total duration of all candidate COTs initiated using the Type 1 channel access procedure is not greater than the length of the transmission gap.

50. The wireless communication method according to claim 42, wherein, The configuration of the transmission gap further includes the repetition information of the transmission gap.

51. The wireless communication method according to claim 50, wherein, The repetition information of the transmission gap includes at least one of the following: the repetition factor of the transmission gap or the time gap between two repetitions.

52. The wireless communication method according to claim 1, further comprising: In the case where the following conditions are satisfied, the first wireless communication entity transmits the positioning reference signal in multiple successfully accessed channels: The successfully accessed channels are consecutive, and the number of the consecutive channels is not less than a threshold.

53. The wireless communication method according to claim 1, further comprising: In the case where the following conditions are satisfied, the first wireless communication entity transmits the positioning reference signal in a channel mode: The successfully accessed channel corresponds to the channel mode.

54. The wireless communication method according to claim 53, wherein, The channel mode is configured by a core network entity.

55. The wireless communication method according to claim 53, wherein, The second wireless communication entity receives the positioning reference signal according to the channel mode.

56. The wireless communication method according to claim 1, wherein, The transmission of the positioning reference signal and the transmission of another positioning reference signal sent by another first wireless communication entity are configured in a comb-like multiplexing manner.

57. The wireless communication method according to claim 1, further comprising: The first wireless communication entity sends access channel information and the configuration of the positioning reference signal to a third wireless communication entity; wherein, the access channel information includes at least one of the following: access RB set ID, the starting position of the access RB set in the frequency domain, or the bandwidth of each access RB set; wherein, the configuration of the positioning reference signal includes at least one of the following: the comb size of the positioning reference signal; or the comb offset of the positioning reference signal.

58. The wireless communication method according to claim 1, wherein, The one or more channel occupancy parameters are sent by the first communication entity or the second communication entity to the core network entity.

59. The wireless communication method according to claim 58, wherein, The one or more channel occupancy parameters include at least one of the following: COT ID; the COT length; the COT start time; the RB set ID occupied by the positioning reference signal within the COT; the start position of the RB set within the COT in the frequency domain; or the bandwidth of each RB set within the COT.

60. The wireless communication method according to claim 1, wherein, The second communication entity receives a positioning reference signal as a DL-PRS according to a reception configuration configured by a higher layer or a core network entity of the first communication entity.

61. The wireless communication method according to claim 60, wherein, The reception configuration includes a first search space set group and a second search space set group corresponding to the COT, wherein the first search space set group is configured to detect DCI outside the COT, and the second search space set group is configured to receive the DL-PRS within the COT.

62. The wireless communication method according to claim 61, wherein, The second search space set group is associated with the period of the positioning reference signal resource.

63. The wireless communication method according to claim 60, wherein, The reception configuration includes a search window, wherein the search window is periodic or aperiodic.

64. The wireless communication method according to claim 63, wherein, When the search window is periodic, the configuration of the search window includes at least one of the following: the length of the search window, the period of the search window, or the start time of the first period of the search window.

65. The wireless communication method according to claim 63, wherein, When the search window is aperiodic, the configuration of the search window includes: the length of the search window, or the period of the search window.

66. The wireless communication method according to claim 60, wherein, The reception configuration includes a search space set group corresponding to the search window, wherein the search space set group is configured to receive the DL-PRS within the search window.

67. The wireless communication method according to claim 60, wherein, The second wireless communication entity continuously receives the positioning reference signal as a DL-PRS within the search window.

68. A non-transitory computer-readable medium storing instructions that, when executed by at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 67.

69. An apparatus, comprising: at least one processor configured to perform the method according to any one of claims 1 to 67.

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