Communication method, device and system

Abstract

The invention relates to a communication method, device and system. And the first terminal device determines a first resource in a resource selection window in a first resource set, the first resource being used for sending the first sidelink reference signal, and the first resource set being a dedicated resource set of the sidelink reference signal. And the first terminal equipment sends first information to the second terminal equipment, wherein the first information is used for indicating the first resource. And the first terminal device sends the first sidelink reference signal on the first resource. According to the embodiment of the invention, the resource set for sending the reference signal is provided, for example, the resources in the resource set can be used for sending the reference signal and are not used for sending data, so that the data and the reference signal can be sent in different resources, and the influence of the reference signal on the data receiving quality is reduced.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method, device and system. Background Art

[0002] The existing sidelink (SL) channel state information-reference signal (CSI-RS) configuration of frequency range (FR) 1 is selected by the transmitting (TX) user equipment (UE), and the SL CSI-RS configuration is provided to the receiving (RX) UE through the PC5-radio resource control (RRC) message. The SL CSI-RS configuration includes information such as the resource mapping mode and number of antenna ports of the SL CSI-RS. In the new radio (NR) vehicle to everything (V2X), the resource mapping of SL CSI-RS in the physical resource block (PRB) is based on the CSI-RS resource mapping mode in the NR Uu. According to the CSI-RS resource mapping mode, SL CSI-RS supports up to 2 antenna ports (such as the SL in NR V2X can support up to two streams in the physical sidelink shared channel (PSSCH)), and the frequency domain density is 1, that is, one SL CSI-RS is configured on each resource block (RB).

[0003] Figure 1A schematic diagram of a time slot structure of SL is given, which includes signals such as automatic gain control (AGC), physical sidelink control channel (PSCCH), PSSCH, demodulation reference signal (DMRS), and may also include a guard interval. SL CSI-RS only supports unicast transmission and is sent along with data in the PSSCH within the time slot. At the same time, SL CSI-RS is not transmitted on orthogonal frequency division multiplexing (OFDM) symbols containing PSCCH, second stage sidelink control information (SCI) or DMRS.

[0004] In FR2, the device may send signals through beams. Unlike FR1, the UE may send SL CSI-RS on multiple OFDM symbols in one time slot, and different SL CSI-RS may correspond to different beam directions. Reference signals in different beam directions may affect the reception quality of PSSCH. Summary of the invention

[0005] Embodiments of the present application provide a communication method, device, and system for reducing the impact of a reference signal on a data receiving process.

[0006] In a first aspect, a communication method is provided, which can be executed by a terminal device, or by other devices including terminal device functions, or by a chip system (or, chip) or other functional modules, which can realize the functions of the terminal device, and the chip system or functional module is, for example, arranged in the terminal device. The terminal device is, for example, a first terminal device. In the following description, the method is performed by the first terminal device as an example. The method comprises: determining a first resource within a resource selection window in a first resource set, the first resource being used to send a first sidelink reference signal, the first resource set being a dedicated resource set for the sidelink reference signal; sending first information to a second terminal device, the first information being used to indicate the first resource; and sending the first sidelink reference signal at the first resource.

[0007] An embodiment of the present application provides a resource set for sending a reference signal, and the resource set may include dedicated resources for sending a reference signal, or the resource set may be a resource set dedicated to sending a reference signal, for example, the resources in the resource set may be used to send a reference signal and not used to send data. Thus, the data and the reference signal may not be sent in the same resource, for example, the resource includes a time domain resource, then the data and the reference signal may not be sent in the same time domain resource (for example, the same time slot), thereby reducing the impact of the reference signal on the quality of data reception. The data here, for example, includes information carried on one or more channels of PSSCH, PSCCH or physical sidelink feedback channel (PSFCH).

[0008] In an optional implementation, the first sidelink reference signal is used by the second terminal device to determine a communication beam between the first terminal device and the second terminal device. For example, the first sidelink reference signal is used for beam management or beam scanning, and the second terminal device can align the communication beam between the second terminal device and the first terminal device based on the measurement of the first sidelink reference signal.

[0009] In an optional implementation, the first resource includes a first sub-resource and a second sub-resource, and the first information includes first indication information and second indication information, the first indication information is used to indicate the time domain resource position of the first sub-resource, and the second indication information is used to indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource. The embodiment of the present application defines a first resource set, and the first resource set may include resources within a resource pool and / or include resources outside the resource pool, and the first information may be sent within the resource pool. Therefore, when the first information indicates the time domain resource position of the first sub-resource, it can indicate the absolute time domain position of the first sub-resource without indicating the time interval between the first sub-resource and the first information, so that the receiving end of the first information can accurately determine the time domain position of the first sub-resource.

[0010] In an optional implementation, the first indication information is carried in SFN or DFN, and the SFN or the DFN is used to indicate the time domain position of the first sub-resource; the second indication information is carried in the time offset field, and the time offset field is used to indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource. The first indication information is to indicate the absolute time domain position of the first sub-resource, for example, through SFN or DFN indication, or it can also be indicated in other ways, without limitation. Once the time domain position of the first sub-resource is determined, the time domain position of the second sub-resource can be determined based on the time interval between the first sub-resource and the second sub-resource, that is, it is no longer necessary to indicate the absolute time domain position of the second sub-resource to save indication overhead.

[0011] In an optional implementation, the first resource is a periodic resource, and the first information is further used to indicate a period of the first resource. The first resource may be a non-periodic resource or a periodic resource.

[0012] In an optional implementation, the first information includes third indication information, and the third indication information is used to indicate the starting frequency domain position of the frequency domain resource of the first resource. For example, the number of frequency domain units occupied by the first resource (or the number of frequency domain units occupied by sub-resources in the first resource) may be predefined by the protocol, or configured together when configuring the first resource set, so the first information only needs to indicate the starting frequency domain position of the first resource.

[0013] In an optional implementation, the third indication information is also used to indicate the number of frequency domain units occupied by the first resource. This is equivalent to the third indication information indicating the starting frequency domain position of the frequency domain resource of the first resource and the number of frequency domain units occupied by the first resource. For example, the number can be determined by the first terminal device itself, which can improve scheduling flexibility.

[0014] In an optional implementation manner, the first information is included in a first SCI or MAC CE. Alternatively, the first information may also be included in information of other protocol layers.

[0015] In an optional implementation, the first information is used to indicate the index of the resource unit to which the first resource belongs, wherein the first resource set includes multiple resource units, and each resource unit in the multiple resource units corresponds to an index. In this implementation, the first resource set is divided into multiple resource units in advance, so that the first information can indicate the first resource as long as it indicates the index of the resource unit to which the first resource belongs. This indication method is relatively simple and is also conducive to saving indication overhead.

[0016] In an optional implementation, the index of the resource unit to which the first resource belongs is determined based on the first identifier in the first information, and the first identifier is the source identifier or the destination identifier of the transmitted data, or is the identifier of the first reference signal. For example, each UE can determine the index of the resource unit that the UE should select based on the corresponding identifier. If a UE receives information from other UEs (such as the first information), the receiving UE can also determine the resource unit selected by the other UE based on the identifier indicated by the information (such as the first identifier). In this case, the information does not need to additionally indicate the resource unit selected by the other UE, which is conducive to saving indication overhead.

[0017] In an optional implementation, the index of the resource unit to which the first resource belongs is indicated by the first identifier in the first information, and the fourth indication information and / or the fifth indication information in the first information, the fourth indication information is used to indicate the time domain offset, the time domain offset is the time domain offset of the first resource relative to the resource unit corresponding to the first identifier, the fifth indication information is used to indicate the frequency domain offset, the frequency domain offset is the frequency domain offset of the first resource relative to the resource unit corresponding to the first identifier, wherein the fourth indication information includes information for indicating that the time domain offset is located before or after the first resource in the time domain; wherein the first identifier is the source identifier or the destination identifier of the transmitted data, or the identifier of the first reference signal. If each UE determines the index of the resource unit by the identifier, it is likely that the index of the resource unit corresponding to the identifier of different UEs is the same, and resource conflict will occur. Then, in addition to indicating the first identifier, the first information may also include the fourth indication information and / or the fifth indication information, that is, the resource unit actually selected by the first UE is indicated by the first identifier, and the fourth indication information and / or the fifth indication information, that is, the resource unit actually selected by the first UE is no longer the resource unit directly determined according to the first identifier. Therefore, if the resource unit directly determined according to the first identifier conflicts with the resource unit directly determined according to the identifier corresponding to other UEs, the resource conflict can be avoided in this way.

[0018] In an optional implementation, the method further includes: receiving second sidelink control information, and the resource unit determined according to the second sidelink control information is the same as the resource unit corresponding to the first identifier. For example, if the first UE receives the second sidelink control information and determines that the resource unit selected by the sender of the second sidelink control information is the same as the resource unit directly determined according to the first identifier, the first UE can avoid resource conflicts in the manner described in the previous paragraph.

[0019] In an optional implementation, the first information further includes sixth indication information, and when the sixth indication information is a first value, it indicates that the index of the resource unit to which the first resource belongs is determined according to the first identifier. Whether the UE determines the resource unit according to the identifier can be indicated by corresponding information, thereby making the way in which the UE determines the resource unit more flexible.

[0020] In an optional implementation, the method further includes: obtaining first configuration information, the first configuration information being used to configure the first resource set, wherein the first configuration information includes mapping relationship information between the positions and indexes of the multiple resource units. The first configuration information is, for example, predefined by a protocol, or configured by a network device or a UE (e.g., a first UE, or a second UE, or other UEs except the first UE and the second UE), or preconfigured in the first UE and the second UE.

[0021] In an optional embodiment, the first sidelink reference signal includes multiple sidelink reference signals, at least one sub-time domain unit in a time domain unit included in the first resource is used to send part or all of the sidelink reference signals in the multiple sidelink reference signals, and the beam directions corresponding to the sidelink reference signals carried by different sub-time domain units in the at least one sub-time domain unit are the same or different. The sidelink reference signal is used, for example, for beam management or beam scanning. For example, a time domain unit can send sidelink reference signals in different beam directions, so that sidelink reference signals in more beam directions can be sent in a short time to improve the efficiency of beam management or beam scanning.

[0022] In an optional implementation manner, the first sidelink reference signal includes one or more of the following: SLSSB, SL CSI-RS, or SL DMRS. Alternatively, the first sidelink reference signal may also include other reference signals.

[0023] In a second aspect, another communication method is provided, which can be executed by a terminal device, or by other devices including terminal device functions, or by a chip system (or, chip) or other functional modules, which can realize the functions of the terminal device, and the chip system or functional module is, for example, arranged in the terminal device. The terminal device is, for example, a second terminal device. In the following description, the method is performed by the second terminal device as an example. The method includes: receiving first information, the first information is used to indicate a first resource, the first resource is used to send a first sidelink reference signal, the first resource belongs to a first resource set, and the first resource set is a resource set for sending a reference signal; receiving the first sidelink reference signal at the first resource.

[0024] In an optional embodiment, the method further includes: determining a communication beam between the first terminal device and the second terminal device based on the first sidelink reference signal.

[0025] In an optional embodiment, the first resource includes a first sub-resource and a second sub-resource, and the first information includes first indication information and second indication information, the first indication information is used to indicate the time domain resource position of the first sub-resource, and the second indication information is used to indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource.

[0026] In an optional embodiment, the first indication information is carried in SFN or DFN, and the SFN or DFN is used to indicate the time domain position of the first sub-resource; the second indication information is carried in a time offset field, and the time offset field is used to indicate the time interval between the time domain resources of the first sub-resource and the time domain resources of the second sub-resource.

[0027] In an optional implementation, the first resource is a periodic resource, and the first information is further used to indicate a period of the first resource.

[0028] In an optional implementation, the first information includes third indication information, and the third indication information is used to indicate a starting frequency domain position of a frequency domain resource of the first resource.

[0029] In an optional implementation, the third indication information is further used to indicate the number of frequency domain units occupied by the first resource.

[0030] In an optional implementation, the first information is included in a first SCI or MAC CE.

[0031] In an optional implementation, the first information is used to indicate an index of a resource unit to which the first resource belongs, wherein the first resource set includes multiple resource units, and each resource unit in the multiple resource units corresponds to an index.

[0032] In an optional implementation, the index of the resource unit to which the first resource belongs is determined based on a first identifier in the first information, where the first identifier is a source identifier or a destination identifier of transmitted data, or is an identifier of the first sidelink reference signal.

[0033] In an optional embodiment, the index of the resource unit to which the first resource belongs is indicated by the first identifier in the first information, and the fourth indication information and / or the fifth indication information in the first information, the fourth indication information is used to indicate the time domain offset, and the time domain offset is the time domain offset of the first resource relative to the resource unit corresponding to the first identifier, and the fifth indication information is used to indicate the frequency domain offset, and the frequency domain offset is the frequency domain offset of the first resource relative to the resource unit corresponding to the first identifier, wherein the fourth indication information includes information for indicating that the time domain offset is located before or after the first resource in the time domain; wherein the first identifier is the source identifier or the destination identifier of the sent data, or is the identifier of the first sidelink reference signal.

[0034] In an optional implementation, the first information further includes sixth indication information, and when the sixth indication information is a first value, it indicates that the index of the resource unit to which the first resource belongs is determined according to the first identifier.

[0035] In an optional implementation, the method further includes: obtaining first configuration information, where the first configuration information is used to configure the first resource set, wherein the first configuration information includes mapping relationship information between the positions and indexes of the multiple resource units.

[0036] In an optional embodiment, the first sidelink reference signal includes multiple sidelink reference signals, and at least one sub-time domain unit in a time domain unit included in the first resource is used to send part or all of the sidelink reference signals, and the beam directions corresponding to the sidelink reference signals carried by different sub-time domain units in the at least one sub-time domain unit are the same or different.

[0037] In an optional embodiment, the first sidelink reference signal includes one or more of the following: SLSSB, SL CSI-RS, or SL DMRS.

[0038] Regarding the technical effects brought about by the second aspect or various optional implementations, reference may be made to the introduction to the technical effects of the first aspect or corresponding implementations.

[0039] In a third aspect, a communication device is provided. The communication device may be the first terminal device described in any one of the first aspect to the second aspect. The communication device has the function of the first terminal device. The communication device is, for example, the first terminal device, or a larger device including the first terminal device, or a functional module in the first terminal device, such as a baseband device or a chip system. In an optional implementation, the communication device includes a baseband device and a radio frequency device. In another optional implementation, the communication device includes a processing unit (sometimes also referred to as a processing module) and a transceiver unit (sometimes also referred to as a transceiver module). The transceiver unit can implement a sending function and a receiving function. When the transceiver unit implements the sending function, it can be called a sending unit (sometimes also referred to as a sending module), and when the transceiver unit implements the receiving function, it can be called a receiving unit (sometimes also referred to as a receiving module). The sending unit and the receiving unit can be the same functional module, which is called a transceiver unit, and the functional module can implement the sending function and the receiving function; or, the sending unit and the receiving unit can be different functional modules, and the transceiver unit is a general term for these functional modules.

[0040] In an optional embodiment, the processing unit is used to perform channel access on an unlicensed frequency band; the transceiver unit (or, the sending unit) is used to send SCI, the SCI includes first information, the first information is used to indicate that at least one of the M bits in the second-order SCI is a reserved bit, the M bits are bits used to carry channel occupancy time sharing information COT-SI, and M is a positive integer.

[0041] In an optional embodiment, the processing unit is used to determine a first resource within a resource selection window in a first resource set, the first resource is used to send a first sidelink reference signal, and the first resource set is a dedicated resource set for the sidelink reference signal; the transceiver unit (or, the sending unit) is used to send first information to a second terminal device, and the first information is used to indicate the first resource; the transceiver unit (or, the sending unit) is also used to send the first sidelink reference signal on the first resource.

[0042] In an optional embodiment, the communication device also includes a storage unit (sometimes also referred to as a storage module), and the processing unit is used to couple with the storage unit and execute the program or instructions in the storage unit, so that the communication device can perform the function of the first terminal device described in any one of the first to second aspects above.

[0043] In a fourth aspect, a communication device is provided. The communication device may be the second terminal device described in any one of the first to second aspects. The communication device has the functions of the second terminal device. The communication device is, for example, a second terminal device, or a larger device including a second terminal device, or a functional module in the second terminal device, such as a baseband device or a chip system. In an optional implementation, the communication device includes a baseband device and a radio frequency device. In another optional implementation, the communication device includes a processing unit (sometimes also referred to as a processing module) and a transceiver unit (sometimes also referred to as a transceiver module). For the implementation of the transceiver unit, reference may be made to the introduction of the third aspect.

[0044] In an optional embodiment, the transceiver unit (or, the receiving unit) is used to receive first information, where the first information is used to indicate a first resource, the first resource is used to send a first sidelink reference signal, the first resource belongs to a first resource set, and the first resource set is a resource set used to send a reference signal; the transceiver unit (or, the receiving unit) is also used to receive the first sidelink reference signal on the first resource.

[0045] In an optional embodiment, the communication device also includes a storage unit (sometimes also referred to as a storage module), and the processing unit is used to couple with the storage unit and execute the program or instructions in the storage unit, so that the communication device can perform the function of the second terminal device described in any one of the first aspect to the second aspect above.

[0046] In a fifth aspect, a communication device is provided, which may be a terminal device, or a chip or chip system used in a terminal device. The communication device includes a communication interface and a processor, and optionally, a memory. The memory is used to store a computer program, and the processor is coupled to the memory and the communication interface. When the processor reads the computer program or instruction, the communication device executes the method executed by the first terminal device or the second terminal device in the above aspects.

[0047] In a sixth aspect, a communication system is provided, comprising a first terminal device and a second terminal device, wherein the first terminal device is used to execute the method performed by the first terminal device described in the first aspect, and the second terminal device is used to execute the method performed by the second terminal device described in the second aspect. For example, the first terminal device can be implemented by the communication device described in the third aspect or the fifth aspect; the second terminal device can be implemented by the communication device described in the fourth aspect or the fifth aspect.

[0048] In a seventh aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium is used to store a computer program or instruction, and when the computer-readable storage medium is executed, the method executed by the first terminal device or the second terminal device in the above aspects is implemented.

[0049] According to an eighth aspect, a computer program product comprising instructions is provided, which, when executed on a computer, enables the methods described in the above aspects to be implemented.

[0050] In a ninth aspect, a chip system is provided, comprising a processor and an interface, wherein the processor is used to call and execute instructions from the interface so that the chip system implements the above-mentioned methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 A schematic diagram of a time slot structure of SL;

[0052] Figure 2 Schematic diagram of the position of SL CSI-RS of two ports in PRB;

[0053] Figure 3A It is a schematic diagram of the P-1 state during beam management;

[0054] Figure 3B It is a schematic diagram of the P-2 state during beam management;

[0055] Figure 3C It is a schematic diagram of the P-3 state during beam management;

[0056] Figure 4 A schematic diagram of an application scenario of an embodiment of the present application;

[0057] Figure 5 A flow chart of a communication method provided in an embodiment of the present application;

[0058] Fig. 6A and Figure 6B Two schematic diagrams of resource units included in the first resource set provided in an embodiment of the present application;

[0059] Figure 7 A schematic diagram of resource selection by a UE in an embodiment of the present application;

[0060] Fig. 8A and Figure 8B Two schematic diagrams of the frequency domain resource positions of the first reference signal and the first PSSCH in the embodiments of the present application;

[0061] Fig. 9 A schematic diagram of a time domain resource position and a frequency domain resource position of a first resource indicated by first information in an embodiment of the present application;

[0062] Fig.10 A schematic diagram of indicating the index of the resource unit to which the first resource belongs through the field in the first information in an embodiment of the present application;

[0063] Fig.11A and Fig. 11B Two schematic diagrams of methods for resolving resource conflicts provided in embodiments of the present application;

[0064] Fig.12 A schematic diagram of a device provided in an embodiment of the present application;

[0065] Fig.13 A schematic diagram of another device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

[0067] In the embodiments of the present application, the number of nouns, unless otherwise specified, means "singular noun or plural noun", that is, "one or more". "At least one" means one or more, and "plural" means two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. For example, A / B means: A or B. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c means: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, c can be single or multiple.

[0068] The ordinal numbers such as "first" and "second" mentioned in the embodiments of the present application are used to distinguish multiple objects, and are not used to limit the size, content, order, timing, priority or importance of multiple objects. In addition, the numbering of the steps in the various embodiments introduced in the present application is only to distinguish different steps, and is not used to limit the order between the steps. For example, S501 may occur before S502, or may occur after S502, or may also occur at the same time as S502.

[0069] Below, some terms or concepts in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

[0070] In an embodiment of the present application, the terminal device is a device with wireless transceiver functions, which can be a fixed device, a mobile device, a handheld device (such as a mobile phone), a wearable device, a vehicle-mounted device, or a wireless device built into the above devices (for example, a communication module, a modem, or a chip system, etc.). The terminal device is used to connect people, objects, machines, etc., and can be widely used in various scenarios, such as but not limited to the following scenarios: perception scenarios, cellular communications, device-to-device communications (D2D), vehicle to everything (V2X), machine-to-machine / machine-type communications (M2M / MTC), Internet of Things (IoT), virtual reality (VR), augmented reality (AR), industrial control, self driving, remote medical, smart grid, smart furniture, smart office, smart wear, smart transportation, smart city, drones, robots, indoor commercial scenarios (such as mobile phone screen projection, file sharing, mobile phone to VR glasses video transmission) and other scenarios of terminal devices. When the terminal device is applied to V2X, it can also be called V2X device, for example, smart car (smart car or intelligent car), digital car (digital car), unmanned car (unmanned car or driverless car or pilotless car or automobile), automatic car (self-driving car or autonomous car), pure electric vehicle (pure EV or Battery EV), hybrid electric vehicle (hybrid electric vehicle, HEV), range extended EV (REEV), plug-in hybrid electric vehicle (plug-in HEV, PHEV), new energy vehicle (new energy vehicle), roadside unit (road site unit, RSU). The terminal device can also be a device in D2D communication, such as an electric meter, a water meter, etc.

[0071] In addition, in the embodiments of the present application, the terminal device can also be a terminal device in an IoT system. IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, thereby realizing an intelligent network that interconnects people and machines and things.

[0072] The various terminal devices introduced above, if located on a vehicle (e.g., placed in a vehicle or installed in a vehicle), can all be considered as vehicle-mounted terminal devices, which are also called on-board units (OBU). The terminal device of the present application can also be an on-board module, on-board module, on-board component, on-board chip or on-board unit built into the vehicle as one or more components or units, and the vehicle can implement the method of the present application through the built-in on-board module, on-board module, on-board component, on-board chip or on-board unit.

[0073] The terminal device may sometimes be referred to as UE, terminal, access station, UE station, remote station, wireless communication device, or user equipment, etc.

[0074] In the embodiment of the present application, the communication device for implementing the function of the terminal device may be a terminal device, or may be a device capable of supporting the terminal device to implement the function, such as a chip system, which may be installed in the terminal device. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for implementing the function of the terminal device as an example, and the terminal device is used as an example. In addition, for the convenience of description, the terminal device is described in the embodiment of the present application by taking the UE as an example.

[0075] The network equipment in the embodiment of the present application, for example, includes access network equipment, and / or core network equipment. The access network equipment is a device with wireless transceiver function, which is used to communicate with the terminal device. The access network equipment includes but is not limited to base stations (base transceiver station (BTS), Node B, evolved node B (eNodeB) / eNB, or next generation node B (gNodeB) / gNB), transceiver points (transmission reception point, TRP), base stations of subsequent evolution of the third generation partnership project (3rd generation partnership project, 3GPP), access nodes in wireless fidelity (Wi-Fi) systems, wireless relay nodes, wireless backhaul nodes, etc. The base station can be: a macro base station, a micro base station, a micro-micro base station, a small station, a relay station, etc. Multiple base stations can support networks with the same access technology, or networks with different access technologies. The base station can include one or more co-station or non-co-station transmission and receiving points. The access network device may also be a wireless controller, a centralized unit (CU), and / or a distributed unit (DU) in a cloud radio access network (CRAN) scenario. The access network device may also be a server, etc. For example, the network device in the V2X technology may be an RSU. The following describes the access network device using a base station as an example. A base station may communicate with a terminal device, or may communicate with a terminal device through a relay station. A terminal device may communicate with multiple base stations in different access technologies. The core network device is used to implement functions such as mobility management, data processing, session management, policy and billing. The names of the devices that implement the core network functions in systems with different access technologies may be different, and the embodiments of the present application do not limit this. Taking the fifth generation mobile communication technology (5G) system as an example, the core network device includes: access and mobility management function (AMF), session management function (SMF), policy control function (PCF) or user plane function (UPF), etc.

[0076] In the embodiment of the present application, the communication device for realizing the function of the network device may be a network device, or may be a device capable of supporting the network device to realize the function, such as a chip system, which may be installed in the network device. In the technical solution provided in the embodiment of the present application, the technical solution provided in the embodiment of the present application is described by taking the device for realizing the function of the network device as an example that the network device is used as the device.

[0077] Figure 1 A schematic diagram of the SL time slot structure is given. The time slot includes signals such as AGC, PSCCH, PSSCH, DMRS, and may also include a guard interval. SL CSI-RS only supports unicast transmission and is sent along with data in the PSSCH within the time slot. At the same time, SL CSI-RS is not transmitted on OFDM symbols containing PSCCH, second-level SCI or DMRS. Each PRB in the PSSCH uses the same pattern for SL CSI-RS, please refer to Figure 2 , is a schematic diagram of the location of the SL CSI-RS of two ports in the PRB, Figure 2 The last symbol represents the gap (GAP). Figure 2 The figure shows one PRB, and PSSCH can occupy multiple PRBs (e.g. Figure 2 Taking PSSCH occupying 30 PRBs as an example), the format of each PRB may be the same.

[0078] Unlike FR1, in FR2, devices may send signals through beams. The frequency range definitions of FR1 and FR2 are shown in Table 1.

[0079] Table 1

[0080]

[0081]

[0082] Beam management is an important technology proposed by 5G NR for FR2. It refers to the process by which base stations and UEs obtain and maintain beam sets for transmission and reception. It is a reference workflow for beamforming in multi-input multi-output (MIMO) systems. According to the working state, beam management can be divided into three states. The operations of each state are summarized as follows:

[0083] P-1: The UE measures the base station's transmit beam set and selects the base station's transmit beam and the UE's receive beam from it. For details, see Figure 3A , is a schematic diagram of P-1;

[0084] P-2: Based on the beam selected by P-1, the UE measures a smaller set of base station transmit beams (beamlets) to improve the BS transmit beam. The smaller set of transmit beams may include some of the beams selected by P-1. Figure 3B , is a schematic diagram of P-2;

[0085] P-3: The UE uses different receive beams to measure the same transmit beam improved according to P-2 to improve the UE's receive beam. For details, see Figure 3C , which is a schematic diagram of P-3.

[0086] In FR2, the UE may send SL CSI-RS on multiple OFDM symbols in one time slot, and different SL CSI-RS may correspond to different beam directions. For example, the UE may send multiple SL CSI-RS with different beam directions in one time slot during beam management, or may send multiple SL CSI-RS with different beam directions in one time slot during other communication processes. Figure 1 It can be seen that SL adjusts the received signal strength by performing AGC on the entire frequency band through the first OFDM symbol in the time slot, thereby ensuring data reception in the entire time slot (the transmission power in the entire time slot no longer changes). In FR2, if the transmitting UE sends SL CSI-RS in multiple beam directions in a time slot, the change in beam direction will cause the receiving power of the UE receiving data to change rapidly in a time slot. The AGC of the first OFDM symbol in the time slot cannot accurately reflect the received signal strength of the entire time slot. The receiving power determined by the UE receiving data according to the AGC may not be adapted to the transmission power of the PSSCH in the time slot, resulting in reduced reception quality of the PSSCH for the UE receiving data.

[0087] In view of this, an embodiment of the present application provides a resource set for sending a reference signal, and the resources within the resource set can be used to send a reference signal. It can be understood that the resources within the resource set can be used to send a reference signal and not for sending data, so that the data and the reference signal may not be sent in the same resource. For example, if the resource includes a time domain resource, the data and the reference signal may not be sent in the same time domain resource, thereby reducing the impact of the reference signal on the data reception quality.

[0088] The technical solution provided in the embodiments of the present application can be applied to the fourth generation mobile communication technology (the 4th generation, 4G) system, such as the long term evolution (long term evolution, LTE) system, or can be applied to the fifth generation mobile communication technology (the 5th generation, 5G) system, such as the NR system, or can also be applied to the next generation mobile communication system or other similar communication systems, such as the sixth generation mobile communication technology (the 6th generation, 6G) system, etc., without specific limitation. In addition, the technical solution provided in the embodiments of the present application can be applied to SL. For example, the SL-U belongs to a D2D scenario, such as an NR-D2D scenario, etc., or belongs to a V2X scenario, such as an NR-V2X scenario, etc. For example, the embodiments of the present application can be used in fields such as factory manufacturing, whole-house intelligence, intelligent driving, assisted driving, intelligent networked vehicles, or indoor commercial scenarios. For example, the embodiments of the present application can be applied to high-frequency bands, such as FR2.

[0089] For reference Figure 4 , which is a communication network architecture applicable to the embodiments of the present application. Figure 4 Including UE1 and UE2, UE1 and UE2 can communicate through SL, for example, UE1 can send a reference signal, and UE2 can receive a reference signal from UE1; or UE1 can send a reference signal and data in different resources respectively, and UE2 can receive a reference signal and data from UE1. Among them, the UE1 and / or UE2 can be within the coverage of the network device, or can also be outside the coverage of the network device. If the UE1 and UE2 are within the coverage of the network device, the two UEs can be within the coverage of the same network device, or can also be within the coverage of different network devices. The UE1 and UE2 can execute the method provided in the embodiment of the present application.

[0090] In addition, the embodiments of the present application may also involve more UEs. For example, in addition to UE2, more UEs may receive reference signals and / or data from UE1, and there is no limitation to this.

[0091] In addition, the embodiments of the present application may also involve more network devices, or may not involve any network devices, and there is no limitation on this.

[0092] In order to better introduce the embodiments of the present application, the method provided by the embodiments of the present application is introduced below in conjunction with the accompanying drawings.

[0093] In various embodiments of the present application, the reference signal is, for example, a SL reference signal, and the SL reference signal includes, for example, one or more of the following: SL CSI-RS, SL synchronization signal and physical broadcast channel (physical broadcast channel, PBCH) block (synchronization signal / PBCH block, SSB), or, SL DMRS. Or the SL reference signal may also include other reference signals. In various embodiments of the present application, the time domain unit is, for example, a subframe, a time slot, a mini-slot, or an OFDM symbol group, and the sub-time domain unit is a next-level time domain unit included in the time domain unit. For example, the time domain unit is a subframe, and the sub-time domain unit is a time slot, a mini-slot, an OFDM symbol group, or an OFDM symbol; or, the time domain unit is a time slot, and the sub-time domain unit is a mini-slot, an OFDM symbol group, or an OFDM symbol; or, the time domain unit is a mini-slot, and the sub-time domain unit is an OFDM symbol group or an OFDM symbol; or, the time domain unit is an OFDM symbol group, and the sub-time domain unit is an OFDM symbol. An OFDM symbol group may include one or more OFDM symbols. For simplicity, OFDM symbols are referred to as symbols hereinafter.

[0094] In various embodiments of the present application, the frequency domain unit is, for example, a sub channel, a resource block (RB) set, a physical resource block (PRB), a carrier or a subcarrier, etc.

[0095] Unless otherwise specified below, the steps represented by dotted lines in the drawings corresponding to the various embodiments of the present application are all optional steps.

[0096] The methods provided in each embodiment of the present application can be applied to Figure 4 The network architecture shown in FIG. 1 is a first UE in the embodiment of the present application. Figure 4 UE1 in the embodiment of the present application; the second UE involved in each embodiment of the present application may be Figure 4 UE2 in .

[0097] This application embodiment provides a communication method, see Figure 5 , which is a flow chart of the method.

[0098] S501. A first UE determines a first resource within a resource selection window in a first resource set.

[0099] The first resource is used to send a first reference signal. For example, the first UE adopts a mode of self-selected resources, i.e., mode 2. Under mode 2, the first UE selects resources from the resource pool by itself, without the need for the network device to schedule resources for the first UE. In the embodiment of the present application, if the first UE wants to send a reference signal, it selects resources from the first resource set. Therefore, the resource selection window is not a traditional resource selection window (the traditional resource selection window is, for example, a resource selection window defined in the protocol of version (Release 16)), but a resource selection window located in the first resource set. The time domain start position and the time domain end position of the resource selection window are both located in the first resource set, and last for a first duration in the time domain. The resource selection window, for example, includes part or all of the resources in the first resource set. The first resource set will be introduced later. To send a first reference signal, the first UE can select a resource in the resource selection window, for example, the first resource is selected. The first resource may include one or more resources. For the sake of distinction, the resources included in the first resource may also be referred to as sub-resources, for example, the first resource includes one or more sub-resources. Each sub-resource may be used to send a reference signal, and the first reference signal may also include one or more reference signals.

[0100] Taking the time domain unit as a time slot as an example, for example, the first UE triggers resource selection in time slot n, a resource selection process of the first UE is introduced as follows. The resources described in the following resource selection process include time domain resources and frequency domain resources. Before introducing the resource selection process, the structure of the first resource set in the embodiment of the present application is first introduced.

[0101] Optionally, the resources included in the first resource set may be an existing structure. For example, the first resource set may include a plurality of physical resource blocks (PRBs), or a plurality of resource elements (CEs).

[0102] Alternatively, the first resource set may include multiple resource units, for example, the first resource set includes T*F resource units, where T represents the number of time domain units included in the resource units in the first resource set, and F represents the number of frequency domain units included in the resource units in the first resource set. Fig. 6A or Figure 6B The figure shows an example of resource units included in the first resource set. Fig. 6A and Figure 6B The first resource set is located outside the resource pool. Fig. 6A and Figure 6BTake T=2 and F=5 as examples. For example, if the first resource set is configured by a network device or a UE, the network device or the UE may pre-divide the resources in the first resource set into T*F resource units; or if the first resource set is pre-defined by a protocol, the protocol may pre-define the T*F resource units included in the first resource set. For example, a resource unit includes a time domain unit in the time domain and a frequency domain unit in the frequency domain. Taking the time domain unit as a time slot and the frequency domain unit as a subchannel as an example, a resource unit includes a time slot and a subchannel on the time slot. For example, as described in the previous article, the first resource may include one or more sub-resources, each of which may include one or more resource units.

[0103] Each resource unit in the plurality of resource units in the first resource set may correspond to an index. When setting the index for the resource units in the first resource set, the index may be set according to a corresponding rule, which may be specified by a network device or a UE (e.g., a first UE, a second UE, or another UE), or may be predefined by a protocol. For example, a rule is a numbering method that firstly numbers the time domain and then the frequency domain. Fig. 6A As shown, the first resource set includes resource units 0 to 9. For another example, another rule is to number the frequency domain first and then the time domain. Figure 6B As shown, the first resource set includes resource units 0-9.

[0104] A resource selection process of the first UE is introduced below.

[0105] 1. The first UE determines a time domain unit and The candidate resources R are continuous frequency domain units. x,y , For example, the number of frequency domain units included in the frequency domain resources used to send the reference signal, or the number of frequency domain units included in the sub-frequency domain resources used to send the reference signal. For example, the first UE may determine the resource selection window in the first resource set, the candidate resource R x,y 2. The first UE determines a resource sensing window (or resource listening window) corresponding to the resource selection window.

[0106] 3. The first UE initializes the available resource set S A , S A Includes all resources in the resource selection window.

[0107] 4. The first UE receives the data from S AThe following resources are excluded: the time slots of all periodic resource reservations configured by the resource pool corresponding to the unperceived time slots (transmitted time slots) in the resource perception window. Among them, the unperceived time slot can be understood as the time slot in which the first UE sends data, or as the time slot used for the first UE to send data, so the first UE has no perception result in this time slot. In order to avoid conflicts, the first UE can assume that there is reservation information sent by other UEs in the time slot (for example, reservation information is carried by SCI), and the time slot may have reserved resources for periodic transmission, then the first UE needs to exclude all available periodic resources configured by all resource pools (since all frequency domain resources are possible, the entire time slot is excluded). Among them, step 4 is an optional step.

[0108] 5. The first UE continues to A The following time-frequency resources are excluded: the received SCI or media access control (MAC) control element (CE) is decoded successfully, and the RSRP measured for the physical sidelink shared channel (PSSCH) demodulation reference signal (DMRS) of the resources reserved by the SCI or MAC CE is higher than the corresponding RSRP threshold, and the resources reserved by the SCI or MAC CE are located within the resource selection window, wherein the resources reserved by the SCI or MAC CE can be used for retransmission and / or periodic transmission.

[0109] The first UE may use the finally determined S A The first UE reports to a higher layer of the first UE, such as a media access control (MAC) layer. A A resource is randomly selected from the random selection list for sending a first reference signal. For example, the first UE selects a resource (r 0 ,r 1 ,r 2 ,…).

[0110] If the resource units are not divided in the first resource set, the first UE may select a resource for sending the first reference signal in the resource selection window of the first resource set according to the above process. For example, the first UE finally selects the first resource (for example, the first resource is resource (r 0 ,r 1 ,r 2 ,…)).

[0111] Alternatively, if resource units are divided in the first resource set, the first UE may also select a resource for sending the first reference signal in the resource selection window of the first resource set according to the above process. For example, the first UE finally selects the first resource (for example, the first resource is resource (r 0 ,r 1 ,r 2 ,…)); or, if resource units are divided within the first resource set, the above process may also be changed accordingly.

[0112] For example, if resource units are divided within the first resource set, then before executing step 5 as above, the first UE may first determine the index of the resource unit that the first UE should select based on the first identifier, and the resource unit is located, for example, within the resource selection window. After determining the index, the first UE also determines the corresponding resource unit. The first identifier is, for example, a source identifier (source ID) or a destination identifier (destination ID) of transmitted data, or an identifier of a first reference signal. For example, if the first UE is a data transmitter, the source identifier is the identifier of the first UE; if the second UE is a data receiver, the source identifier is the identifier of the second UE. For example, the resources determined by the first UE based on the first identifier may satisfy the following relationship:

[0113] C = First Mark % (T*F) (Formula 1)

[0114] In Formula 1, C represents the index of the resource selected by the first UE, % represents the division modulus operation, T represents the number of time domain units included in the resource unit in the first resource set, and F represents the number of frequency domain units included in the resource unit in the first resource set. Alternatively, the resource selected by the first UE may also satisfy other relationships, which are not specifically limited.

[0115] If the first UE uses an identifier to select resources, then different UEs may all use the same method to select resources for sending reference signals. For example, if the second UE wants to send a reference signal, the second UE can select resources based on a second identifier, where the second identifier is, for example, a source identifier or a destination identifier of data to be sent by the second UE, or an identifier of a reference signal to be sent by the second UE. That is, different UEs select resources based on identifiers, and the indexes of resource units to which resources selected by different UEs belong may be different or the same. Optionally, if the resource units to which resources selected by different UEs belong are the same, a resource conflict occurs. Therefore, optionally, in order to reduce the occurrence of transmission failures and the like caused by resource conflicts, after the first UE determines the index of the resource unit based on the first identifier, it may continue to determine whether the resource unit conflicts with resource units that have been reserved by other UEs, that is, determine whether other UEs have reserved the resource unit.

[0116] For example, the first UE receives information from other UEs (the information is, for example, SCI, for example, called the second SCI, or the information may also be SL MAC CE, or the information may also be information of other protocol layers), and the other UE is, for example, the second UE, or other UEs other than the first UE and the second UE. The information indicates the index of the resource unit used by the other UE to send a reference signal. If the index is the same as the index of the resource unit corresponding to the first identifier, a resource conflict occurs. Alternatively, if the information (such as SCI or MAC CE) received by the first UE from other UEs does not reserve the resource unit determined by the first UE according to the first identifier, the first UE determines that no resource conflict occurs.

[0117] If no resource conflict occurs, the first UE may not need to perform step 5 as above, but instead uses the resource determined according to the first identifier as the final selected resource for sending the first reference signal, for example, the resource is the first resource, and the resource selection process ends.

[0118] Alternatively, if a resource conflict occurs, the first UE may perform step 5 as above, which is equivalent to the first UE giving up using the resource directly determined according to the first identifier and reselecting a resource within the resource selection window. In this case, the resource selected by the first UE through step 5 as above is the resource finally selected for sending the first reference signal, for example, the resource is the first resource.

[0119] For example, reference Figure 7 , is a schematic diagram of UE resource selection, taking the UE as UE1 as an example. According to the resource selection process described above, for example, UE1 performs resource sensing and receives SCI from UE2 and SCI from UE3 within the resource listening window. The SCI of UE2 indicates resource R1, and resource R1 is within the resource selection window of UE1. The SCI of UE3 indicates resource R3, and resource R3 is within the resource selection window of UE1. Resource R3 is used for retransmission, for example; in addition, the SCI of UE3 also indicates a period, indicating that UE3 has reserved a periodic resource, for example, the periodic resource reserved by UE3 is resource R3. UE1 triggers resource selection in time slot n. When performing resource selection, it does not select resources R1, R2, and R3, but selects resources from the remaining resources in the resource selection window.

[0120] The first resource set involved in the embodiments of the present application may be a set of dedicated resources configured for beam management (or beam scanning), or the first resource set does not overlap with resources used to send data (e.g., PSSCH), or the first resource set may include dedicated resources for sending reference signals, or the first resource set may be a resource set dedicated to sending reference signals, for example, resources within the first resource set may be used to send reference signals but not for sending data (e.g., not for sending PSSCH). The first resource set does not overlap with resources used to send data, for example, the time domain resources in the first resource set do not overlap with the time domain resources used to send data; or the time domain resources in the first resource set do not overlap with the time domain resources used to send data, and the frequency domain resources in the first resource set do not overlap with the frequency domain resources used to send data. Optionally, all resources within the first resource set are used only to send reference signals and not for sending data, for example, not used to send PSSCH, not used to send PSCCH, not used to send PSFCH, etc.; or, all resources within the first resource set are used only to send reference signals and not for sending other information besides reference signals, such other information including, for example, data and / or control information, etc.

[0121] For example, if the reference signal and data (such as PSSCH) are sent in the same time slot, according to the current time slot structure, the receiving UE can only adjust the received signal strength by performing AGC on the entire frequency band through the first OFDM symbol in the time slot, thereby ensuring the data reception of the entire time slot. In FR2, the reference signal in the time slot may be sent in multiple beam directions, and the change of the beam direction will cause the receiving power of the receiving UE in a time slot to change rapidly. The AGC of the first OFDM symbol in the time slot cannot accurately reflect the received signal strength of the entire time slot, and the receiving power determined by the receiving UE according to the AGC may not be adapted to the transmission power of the data in the time slot, thereby causing the receiving UE to reduce the reception quality of the data. The embodiment of the present application sets a first resource set dedicated to sending a reference signal. When sending a reference signal, the UE selects resources from the first resource set instead of selecting resources from the resources used to send data, and when sending data, it selects resources from the resources used to send data (such as a resource pool) instead of selecting resources from the first resource set. Since the time domain resources included in the first resource set do not overlap with the time domain resources used to send data, the reference signal and the data will not be sent in the same time domain resources (for example, the same time slot), that is, the reference signal and the data will be sent in different time domain resources (for example, time slots), thereby reducing the impact of the reference signal on the data reception quality, so that both the reference signal and the data can have better reception and transmission quality.

[0122] For example, a first resource set can be set for a bandwidth part (BWP), and the first resource set can be located in any resource pool within the BWP, or can be located outside all resource pools within the BWP, or the first resource set can also include resources within some or all resource pools within the BWP. Among them, the resource pool configured by the first UE can be located within the BWP. The first resource set can be configured by first configuration information, and the first configuration information can be determined and sent by a network device. Optionally, an embodiment of the present application may also include S502, where the network device sends the first configuration information, and accordingly, the first UE receives the first configuration information. S502, for example, occurs before S501. Alternatively, the first configuration information may also be determined by a certain UE (such as the first UE, the second UE or other UE). If it is determined by a UE other than the first UE, S502 may also be replaced by the UE used to determine the first configuration information sending the first configuration information, and accordingly, the first UE receives the first configuration information. Figure 5 In the example, the network device sends the first configuration information. Alternatively, the first configuration information may also be predefined or preconfigured in some or all UEs in the BWP through a protocol. Optionally, after the first UE obtains the first configuration information, it may determine the resource selection window as described above according to the first configuration information, thereby determining the first resource in the resource selection window.

[0123] Optionally, the first configuration information may include a bitmap, and the bits included in the bitmap may correspond one-to-one to the time domain units included in the first resource pool, or the bits included in the bitmap may correspond one-to-one to the time domain units included in the first BWP, or the bits included in the bitmap may correspond one-to-one to some or all of the time domain units outside all resource pools in the first BWP. The first resource pool is, for example, a resource pool configured for the first UE, and the first BWP is the BWP where the first resource pool is located. For example, if the first resource set is located in the first resource pool, the bits included in the bitmap may correspond one-to-one to the time domain units included in the first resource pool, or the bits included in the bitmap may correspond one-to-one to the time domain units included in the first BWP; alternatively, if the first resource set is located outside all resource pools in the first BWP, the bits included in the bitmap may correspond one-to-one to some or all of the time domain units outside all resource pools in the first BWP, or the bits included in the bitmap may correspond one-to-one to the time domain units included in the first BWP; alternatively, the first resource set includes time domain units in some or all of the resource pools in the first BWP, or the first resource set includes time domain units in some or all of the resource pools in the first BWP, and includes some or all of the time domain units outside all resource pools in the first BWP, then the bits included in the bitmap may correspond one-to-one to the time domain units included in the first BWP. Among them, when the value of a bit in the bitmap is the third value, it indicates that the time domain unit corresponding to the bit belongs to the first resource set; and when the value of a bit in the bitmap is the fourth value or not the third value, it indicates that the time domain unit corresponding to the bit does not belong to the first resource set.

[0124] Alternatively, the first configuration information may not include a bitmap, but may indicate one or more of the following: a starting time domain position of the time domain resources included in the first resource set, a period of the time domain resources included in the first resource set, a number of resources (e.g., time domain units) dedicated to sending reference signals included in one period (e.g., N period The time interval between the first resource dedicated to sending a reference signal in a cycle (including one or more time domain units) and the starting time domain position of the cycle (for example, N offset denoted by N), or the time interval between two adjacent resources dedicated to sending reference signals (one of which includes one or more time domain units) within a period (for example, N intervalThe starting time domain position of the time domain resources included in the first resource set is, for example, SFN or DFN, wherein the time slot index corresponding to the starting time domain position is, for example, 0. In addition, the first configuration information may also indicate the frequency domain resources included in the first resource set, such as indicating the starting frequency domain position and bandwidth of the frequency domain resources included in the first resource set, or indicating the starting frequency domain position and ending frequency domain position of the frequency domain resources included in the first resource set, etc., without limitation.

[0125] For example, regardless of the implementation method in which the first resource set includes resource units or the implementation method in which the first resource set does not include resource units, the first configuration information can be implemented in the manner described in the above two paragraphs. However, for the implementation method in which the first resource set includes resource units, the first configuration information may also include further information. Optionally, for the implementation method in which the first resource set includes resource units, the first configuration information may also include association relationship information between the positions and indexes of some or all resource units in the first resource set; for the UE that obtains the first configuration information, once a certain index is determined, the time domain position and frequency domain position of the resource unit corresponding to the index can be determined.

[0126] S503: The first UE sends first information to the second UE. Correspondingly, the second UE receives the first information from the first UE. The first information is, for example, SCI, or SL MAC CE, or other information.

[0127] The first information may indicate a resource selected by the first UE, for example, indicating a first resource. The first information may be sent to the second UE in a unicast manner; or, the first information may be sent in a broadcast manner, and the second UE may be one of the UEs receiving the first information; or, the first information may be sent in a multicast manner, and the second UE may be one of the UEs in the multicast group receiving the first information.

[0128] The first information may indicate the first resource in different ways, as shown below.

[0129] 1. The first resource set is not divided into resource units.

[0130] In this case, the first information may indicate the time domain resource position and frequency domain resource position of the first resource. Taking the example that the first resource includes two sub-resources, such as the first sub-resource and the second sub-resource, the first information may include the first indication information and the second indication information, the first indication information may indicate the time domain resource position of the first sub-resource, and the second indication information may indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource. Among them, since the embodiment of the present application newly defines the first resource set, the first resource set is not a resource pool, and the first information can be sent in the sending resource pool of the first UE, but the first resource set may be located in the resource pool, or may not be located in the resource pool, or may also include part or all of the resources in the resource pool, so the first information cannot indicate the time interval between the time domain position of the first resource and the time domain position of the first information, but needs to indicate the absolute time domain position of the first resource, that is, the first indication information may indicate the absolute time domain position of the first sub-resource.

[0131] Optionally, the first information includes a system frame number (SFN) field and a time offset field, the first indication information is carried by the SFN field, and the second indication information is carried by the time offset field. The SFN field, for example, includes a direct frame number (DFN) field and a time domain unit index field, the DFN field may indicate the index of the frame where the time domain resource of the first sub-resource is located, and the time domain unit index field may indicate the index of the time domain unit where the time domain resource of the first sub-resource is located in the frame. For example, if the time domain unit is a time slot, the time domain unit index field is, for example, a time slot index field, which may indicate the index of the time slot where the time domain resource of the first sub-resource is located in the frame. The DFN field, for example, includes 10 bits, and the length of the time domain unit index field may be related to the subcarrier spacing. For example, if the subcarrier spacing is 15kHz, the time domain unit index field may include 4 bits; or, if the subcarrier spacing is 60kHz, the time domain unit index field may include 7 bits, and so on. For example, the frame index indicated by the DFN field in the SFN field is 3, the time slot index indicated by the time domain unit index field is 7, and the time interval indicated by the time offset field is 5 time slots. Then, the time domain resource of the first sub-resource is located in the 7th time slot of the 3rd frame, and the time domain resource of the second sub-resource is located 5 time slots after the first sub-resource, that is, the 12th time slot of the 3rd frame. Alternatively, the first information may not include the SFN field, but include the DFN field and the time offset field. The DFN field may indicate the time domain position of the first sub-resource, for example, indicating the index of the frame where the time domain resource of the first sub-resource is located. Optionally, the first information may also include a time domain unit index field, which may indicate the index of the time domain unit where the time domain resource of the first sub-resource is located within the frame.

[0132] Alternatively, the first resource may also include a sub-resource, for example, the first sub-resource, then the first information may include the first indication information but not the second indication information. The implementation method of the first indication information may refer to the above.

[0133] As described above, the first information indicates the time domain resource location of the first resource. The following describes the first information indicating the frequency domain resource location of the first resource. For example, the first information may include third indication information, and the third indication information may indicate the frequency domain resource location of the first resource.

[0134] As an optional implementation of the third indication information, the third indication information can be carried in an existing field in the first information. This method does not need to add a new field in the first information, which is conducive to compatibility with existing technologies. For example, if the information in the format of the first information is originally used to schedule PSSCH, the first information may include a field for indicating the frequency domain resource position of PSSCH. Taking the first information as SCI as an example, the field included in SCI for indicating the frequency domain resource position of PSSCH is, for example, a frequency resource assignment field, and the frequency resource assignment field may include a bit for indicating a frequency domain resource indicator value (FRIV), and the frequency domain resource position of PSSCH can be determined according to the FRIV. Then, the embodiment of the present application can use the frequency field assignment field to indicate the frequency domain resource position of the reference signal, for example, the frequency resource assignment field in the first information can carry the third indication information. Under this indication method, the starting frequency domain position of the reference signal can be the same as the starting frequency domain position of the PSSCH. For example, if the first information schedules the first PSSCH in addition to the first reference signal, the starting frequency domain position of the first reference signal and the starting frequency domain position of the first PSSCH are both indicated by the frequency resource allocation field. The frequency resource allocation indication only indicates one frequency domain position, which is both the starting frequency domain position of the first reference signal and the starting frequency domain position of the first PSSCH.

[0135] Optionally, if the third indication information is carried in an existing field in the first information, one way in which the third indication information indicates the frequency domain resource position of the first resource is that the third indication information may indicate the starting frequency domain position of the frequency domain resource of the first resource. The number of frequency domain units included in the frequency domain resource (or sub-frequency domain resource) used to send the reference signal is, for example, expressed as It can be configured by a network device or a UE, or predefined by a protocol. For example, the number can be included in the configuration information used to configure the first resource set, so the first information indicates the starting frequency domain position of the frequency domain resource of the first resource.

[0136] Taking the first information scheduling of the first reference signal and the first PSSCH as an example, please refer to Fig. 8A , is an example of the frequency domain resource location of the first PSSCH and the first reference signal, Fig. 8ATake the example that the first resource includes the first sub-resource and the second sub-resource, and the example that the resource used to transmit the first PSSCH includes two resources, and the example that the first information is included in the SCI. For example, according to the indication of the time resource assignment field in the first information, the first information reserves the resources after t1 and the resources after t2 for sending the first PSSCH; at the same time, according to the indication of the frequency resource assignment field, the index of the starting sub-channel where the frequency domain resource of the first PSSCH is located can be determined and the number of subchannels L subCH Therefore, the second PSSCH transmission will be after t1 time slots, in the ( Fig. 8A It is represented as a) continuous L on the subchannel subCH The third PSSCH transmission will be carried out on the channel after t2 time slots. ( Fig. 8A It is represented as b) continuous L on the subchannel subCH For example, according to the first indication information and the second indication information, the time domain resource of the first sub-resource is located in the 7th time slot of the 3rd frame, and the time domain resource of the second sub-resource is located 5 time slots after the first sub-resource, that is, the 12th time slot of the 3rd frame. Then, combined with the frequency resource allocation field, it can be known that the time domain resource of the first sub-resource is located in the 7th time slot of the 3rd frame, and in the 12th time slot of the 3rd frame. Continuous Fig. 8A In the channel c), the time domain resource of the second sub-resource is located in the 12th time slot of the 3rd frame. Continuous It can be seen that the starting frequency domain position of the first reference signal is the same as the starting frequency domain position of the first PSSCH.

[0137] As another optional implementation of the third indication information, the third indication information can be carried in a newly added field in the first information. This method does not need to indicate the frequency domain resources of the reference signal through the field used to indicate the frequency domain resources of the PSSCH, so that the reference signal can be better decoupled from the PSSCH, thereby making the transmission of the reference signal more flexible. For example, the newly added field is called the starting subchannel assignment field, or the newly added field can also have other names without limitation. For example, the newly added field can satisfy the following relationship:

[0138]

[0139] In formula 2, starting subchannel assignment indicates the value of the new field. represents the starting frequency domain position of the frequency domain resource of the first sub-resource, represents the starting frequency domain position of the frequency domain resource of the second sub-resource, It can represent the total number of frequency domain units included in the sub-resources within the first resource. For example, if the number of frequency domain units included in different sub-resources included in the first resource is the same, then It can represent the total number of frequency domain units included in any sub-resource within the first resource.

[0140] Optionally, if the third indication information is carried in a newly added field in the first information, one way in which the third indication information indicates the frequency domain resource position of the first resource is that the third indication information may, for example, indicate the starting frequency domain position of the frequency domain resource of the first resource, and indicate the number of frequency domain units occupied by the frequency domain resource of the first resource or the number of frequency domain units occupied by the sub-frequency domain resources included in the first resource. The number of frequency domain units occupied by the frequency domain resources of the first resource or the number of frequency domain units occupied by the sub-frequency domain resources included in the first resource is, for example, expressed as Optional, It can be configured by a network device or a UE, or predefined by a protocol, for example, the number can be included in the configuration information used to configure the first resource set. Or, It can also be determined by the first UE itself. For example, the number of frequency domain units included in the resources scheduled by the first UE for transmitting different reference signals can be the same or different, or the number of frequency domain units included in the resources scheduled by different UEs for transmitting reference signals can be the same or different, which can be more flexible for resource scheduling.

[0141] Taking the first information scheduling of the first reference signal and the first PSSCH as an example, please refer to Figure 8B , is an example of the frequency domain resource location of the first PSSCH and the first reference signal, Figure 8B Take the example that the first resource includes the first sub-resource and the second sub-resource, and the example that the resource used to transmit the first PSSCH includes two resources, and the example that the first information is included in the SCI. For example, according to the indication of the time resource assignment field in the first information, the first information reserves the resources after t1 and the resources after t2 for sending the first PSSCH; at the same time, according to the indication of the frequency resource assignment field in the first information, the index of the starting sub-channel where the frequency domain resource of the first PSSCH is located can be determined and the number of subchannels L subCH Therefore, the second PSSCH transmission will be after t1 time slots, in the ( Fig. 8A It is represented as a) continuous L on the subchannel subCH The third PSSCH transmission will be carried out on the channel after t2 time slots. ( Fig. 8A It is represented as b) continuous L on the subchannel subCH For example, according to the indication of the first indication information and the second indication information, or according to the indication of the SFN field and the time offset field, the time domain resource of the first sub-resource is located in the 7th time slot of the 3rd frame, and the time domain resource of the second sub-resource is located 5 time slots after the first sub-resource, that is, the 12th time slot of the 3rd frame. Combined with the newly added field in the first information, the time domain resource of the first sub-resource is located in the 7th time slot of the 3rd frame, and in the 12th time slot of the 3rd frame. ( Fig. 8A It is represented as continuous ( Fig. 8A In the channel c), the time domain resource of the second sub-resource is located in the 12th time slot of the 3rd frame. ( Fig. 8A It is represented as continuous In the indication mode of the newly added field, the starting frequency domain position of the reference signal and the starting frequency domain position of the PSSCH can be the same or different. Figure 8B Take the example that the starting frequency domain position of the first reference signal is different from the starting frequency domain position of the first PSSCH.

[0142] in Fig. 8A and Figure 8B In the example, resources used to send SCI and the first PSSCH are both located in a resource pool, which is, for example, a resource pool configured by the first UE, such as a first resource pool; the first resource is located in a first resource set, which, for example, has no intersection with the first resource pool.

[0143] Please refer to Fig. 9 , is an example of the first information indicating the time domain resource position and frequency domain resource position of the first resource. For example, the first information indicates the time domain resource position of the first sub-resource through the SFN field and the time offset field, and indicates the starting frequency domain resource position of the first resource through the frequency resource allocation field or the newly added field. Fig. 9 As shown, the receiving end of the first information (eg, the second UE) can determine the first resource according to the SFN field and the time offset field, as well as the frequency resource allocation field or the newly added field. Fig. 9 Take the example that the first resource set is located outside the resource pool.

[0144] 2. Resource units are divided within the first resource set.

[0145] In this manner, the first information may indicate the index of the resource unit to which the first resource belongs, without having to indicate the specific location of the resource unit. The indication manner is relatively simple and helps to save indication overhead.

[0146] For example, although the resource unit is set, the UE does not select the resource unit according to the identifier. For example, the first resource is not determined according to the first identifier, but is determined according to steps 1 to 5 in the resource selection process introduced in S501. Then the first information may indicate the index of the resource unit to which the first resource belongs, so that the receiving end of the first information can determine the resource unit selected by the first UE. Optionally, a new field may be added to the first information, and the new field may indicate the index of the resource unit to which the first resource belongs. For example, refer to Fig.10 Taking the newly added field represented as RS_ID as an example, the index indicated by the RS_ID is 1, for example, then the second UE can determine that the first UE will use resource unit 1 to send a reference signal.

[0147] Alternatively, in the case where a resource unit is set, if the UE selects a resource unit based on an identifier, for example, the first resource is determined based on a first identifier, then the first information may indicate the index of the resource unit to which the first resource belongs, for example, a new field may be added to the first information to indicate the index of the resource unit to which the first resource belongs; or, the first information may not necessarily indicate the index of the resource unit to which the first resource belongs, because the first information includes the first identifier, the receiving end of the first information can determine the index of the resource unit to which the first resource belongs based on the first identifier. That is, in this case, the first information may no longer need to indicate the first resource through a special field, or indicate the location of the first resource. For the receiving end of the first information, the resource unit to be used by the first UE can be determined based on the first identifier, thereby reducing the overhead of the first information. Alternatively, if the UE selects a resource unit based on an identifier, it may also be considered that the first identifier included in the first information indicates the index of the resource unit, that is, the first information still indicates the index of the resource unit, but no new field is added.

[0148] Alternatively, in the case where a resource unit is set, if the UE selects a resource unit based on an identifier, as described above, there may be a resource conflict. As described above, if the resource determined by the first UE based on the first identifier conflicts with the resource reserved by other UEs, the first UE may reselect the resource according to step 5 in the resource selection process in S501. For example, the first UE reselects the first resource, and the first resource is different from the resource directly determined by the first UE based on the first identifier. Then, the first information may indicate the index of the resource unit to which the first resource belongs. For example, the first information includes the first identifier, and the first information may also include fourth indication information and / or fifth indication information. The fourth indication information may indicate a time domain offset, and the fifth indication information may indicate a frequency domain offset, which is equivalent to the first information indicating the index of the resource unit to which the first resource belongs through the first identifier, and the fourth indication information and / or the fifth indication information. For example, the fourth indication information may be carried in the time offset field in the first information, or the field may have other names, such as a newly added field in the first information; the fifth indication information may be carried in the frequency offset field in the first information, or the field may have other names, such as a newly added field in the first information. The time offset indicated by the fourth indication information may be the time offset of the first resource relative to the resource unit corresponding to the first identifier (i.e., the resource unit directly determined according to the first identifier, such as the resource unit determined according to Formula 1), and the frequency offset indicated by the fifth indication information may be the frequency offset of the first resource relative to the resource unit corresponding to the first identifier. For example, the first UE receives the second SCI, and the first UE determines that the index of the resource unit indicated by the second SCI is the same as the index of the resource unit corresponding to the identifier, then a resource conflict occurs. In this case, the first UE reselects the resource for sending the first reference signal, for example, the first UE reselects the first resource. Among them, the first resource may have a time domain offset with the resource corresponding to the first identifier, and / or, the first resource may have a frequency domain offset with the resource corresponding to the first identifier. In short, the first resource and the resource corresponding to the first identifier are different resources. The first information can indicate the first resource by indicating the first identifier, and the fourth indication information and / or the fifth indication information. The receiving end of the first information (e.g., the second UE) can determine the first resource according to the first identifier in the first information, and the fourth indication information and / or the fifth indication information.

[0149] The time domain offset field used to carry the fourth indication information and the aforementioned time offset field used to indicate the time interval between the first sub-resource and the second sub-resource are different fields. If it is necessary to distinguish, the aforementioned time offset field can be referred to as the first time offset field or the first time domain offset field, and the time domain offset field used to carry the fourth indication information can be referred to as the second time offset field or the second time domain offset field.

[0150] Optionally, the fourth indication information may include information for indicating that the time domain offset is located before or after the first resource in the time domain, so that the receiving end of the first information can determine whether the first resource is located before or after the resource unit corresponding to the first identifier in time. For example, the length of the time domain offset field is L time bits (e.g. L time =log 2 T+1), wherein the highest bit or the lowest bit in the time domain offset field is used to indicate that the time domain offset is located before or after the resource unit corresponding to the first identifier. For example, the value of the highest bit or the lowest bit is "0", indicating that the first resource is located after the resource unit corresponding to the first identifier; or, the value of the highest bit or the lowest bit is "1", indicating that the first resource is located before the resource unit corresponding to the first identifier. Other bits in the time domain offset field except the highest bit or the lowest bit can indicate the time domain offset.

[0151] For example, reference Fig.11A, is a schematic diagram of a solution to resource conflicts. The resource unit determined by UE A according to the source ID of UE A (for example, the source ID is 4) is resource unit 4, and the SCI sent by UE A includes the source ID of UE A. The resource units determined according to the identifier of UE B (for example, the source ID is 19) and the identifier of UE C (for example, source ID=34) are both resource unit 4, so UE B and UE C can both determine that a resource conflict has occurred after receiving the SCI. Therefore, UE B can reselect resources. For example, UE B selects resource unit 5. The SCI sent by UE B may include a time domain offset field, and the time domain offset field includes fourth indication information. The value of the highest bit or the lowest bit in the fourth indication information is "0", that is, it indicates that the resource unit selected by UE B is located after resource unit 4. In addition, the values ​​of other bits in the fourth indication information indicate that the time domain offset is 1; then the receiving end of the SCI can determine that UE B selects resource unit 5. In addition, UE C may also reselect resources. For example, UE C selects resource unit 3. The SCI sent by UE C may include a time domain offset field. The time domain offset field includes the fourth indication information. The value of the highest bit or the lowest bit in the fourth indication information is "1", that is, it indicates that the resource unit selected by UE C is located before resource unit 4. In addition, the values ​​of other bits in the fourth indication information indicate that the time domain offset is 1; then the receiving end of the SCI can determine that UE B has selected resource unit 3. Among them, the SCI sent by UE B and UE C, for example, do not include the frequency domain offset field (or the fifth indication information), or the SCI sent by UE B and UE C both include the frequency domain offset field (or the fifth indication information), and the frequency domain offsets indicated by these two frequency domain offset fields (fifth indication information) are both 0. Among them, each SCI is sent within the resource pool ( Fig.11A For example, UE1, UE2 and UE3 are configured with the same resource pool, and the resource unit is located in a first resource set, which has no intersection with the resource pool.

[0152] Optionally, the fifth indication information may include information for indicating that the frequency domain offset is located in the first direction or the second direction of the first resource in the frequency domain, so that the receiving end of the first information can determine in which direction of the resource unit corresponding to the first identifier the first resource is located in the frequency domain. At this time, the first resource set includes T*F resource units, F represents the number of frequency domain units included in the resource units in the first resource set, and the value of F is, for example, 0, 1, 2, 3, ..., or 1, 2, 3, 4, ... For example, the first direction is the direction from large to small value of F (or the direction in which the value of F decreases), and the second direction is the direction from small to large value of F (or the direction in which the value of F increases); or, the first direction is the direction from small to large value of F, and the second direction is the direction from large to small value of F. It is equivalent to that the embodiment of the present application does not need to consider the high or low frequency (for example, for different resource units, the UE may not be able to identify whether the frequency of a resource unit is high or low relative to the frequency of another resource unit), but can indicate the position of the resource unit by indicating the direction of change of F. For example, the highest bit or the lowest bit in the frequency domain offset field is used to indicate that the frequency domain offset is located in the first direction or the second direction of the resource unit corresponding to the first identifier. For example, the value of the highest bit or the lowest bit is "0", indicating that the first resource is located in the first direction of the resource unit corresponding to the first identifier; or, the value of the highest bit or the lowest bit is "1", indicating that the first resource is located in the second direction of the resource unit corresponding to the first identifier. Other bits in the frequency domain offset field except the highest bit or the lowest bit may indicate the frequency domain offset.

[0153] In addition, since the frequency domain range of the first resource set is limited, a situation may occur where, after a certain UE (e.g., the second UE) receives information (e.g., the first information) from another UE (e.g., the first UE), the resource unit corresponding to the index of the resource unit determined according to the first identifier and the fourth indication information and / or the fifth indication information included in the first information exceeds the range of the first resource set. Fig. 6A or Figure 6BTaking the first resource set shown as an example, for example, the second UE receives the SCI from the first UE, if the second UE determines the index of the resource unit according to the first identifier and the fourth indication information and / or the fifth indication information included in the first information, the determined index is 10, and the resource unit 10 is not in the first resource set. In this case, the second UE can recalculate the frequency domain offset from the end point of the first direction or the end point of the second direction in the first resource set to determine the index of the resource unit. For example, if the second UE is offset in the first direction of the resource unit corresponding to the first identifier, the second UE can recalculate the offset from the end point of the second direction of the first resource set. For example, if the first direction is a high-frequency direction and the second direction is a low-frequency direction, the second UE first offsets in the high-frequency direction, and when the highest frequency in the first resource set is reached, the second UE recalculates the offset from the lowest frequency in the first resource set; or, if the second UE is offset in the second direction of the resource unit corresponding to the first identifier, the second UE can recalculate the offset from the end point of the first direction of the first resource set. For example, if the first direction is a high-frequency direction and the second direction is a low-frequency direction, the second UE first offsets in the low-frequency direction, and when the lowest frequency in the first resource set is reached, the second UE recalculates the offset from the highest frequency in the first resource set. This method of determining the resource unit index can be understood as the receiving UE determining the index of the resource unit according to the frequency domain offset in a cyclic manner within the first resource set. For example Fig. 6A In the example, the index of the resource unit directly determined by the second UE according to the first identifier (i.e., the resource unit corresponding to the first identifier) ​​is 4, and the frequency domain offset indicated by the fifth indication information is 4. The second UE starts from the frequency domain position of resource unit 4 and offsets 3 in the first direction. For example, the first direction is the high frequency direction and the second direction is the low frequency direction. The second UE reaches the upper frequency limit of the first resource set. At this time, the frequency domain offset 1 is performed from the lowest frequency of the first resource set, and resource unit 0 and resource unit 1 can be determined. Combined with other information (such as the fourth indication information), it can be determined that the final resource unit is resource unit 0 or resource unit 1.

[0154] Optionally, if the first UE determines the resource unit in a cyclic manner, the fifth indication information may not include information for indicating that the frequency domain offset is located in the first direction or the second direction of the first resource in the frequency domain. For example, for the second UE, if the fifth indication information includes information for indicating that the frequency domain offset is located in the first direction or the second direction of the first resource in the frequency domain, it means that the second UE directly determines the index of the resource unit based on the first identifier, and based on the fourth indication information and / or the fifth indication information included in the first information; and if the fifth indication information does not include information for indicating that the frequency domain offset is located in the first direction or the second direction of the first resource in the frequency domain, it means that the second UE can determine the index of the resource unit in a cyclic manner.

[0155] For example, refer to Fig. 11B , is a schematic diagram of another solution to resource conflicts. The resource unit determined by UE A according to the source ID of UE A is resource unit 4, and the SCI sent by UE A includes the source ID of UE A. The resource units determined according to the identifier of UE B (for example, source ID is 19) and the identifier of UE C (for example, source ID=34) are both resource unit 4, so UE B and UE C can both determine that a resource conflict has occurred after receiving the SCI. Then UE B can reselect resources, for example, UE B selects resource unit 10, and the SCI sent by UE B may include a frequency domain offset field, and the frequency domain offset field includes the fifth indication information, and the value of the highest bit or the lowest bit in the fifth indication information is "1", that is, indicating that the resource unit selected by UE C is located in the second direction of resource unit 4, and the second direction is, for example, the direction in which the value of F increases, and the values ​​of other bits in the fifth indication information indicate that the frequency domain offset is 2; then the receiving end of the SCI can determine that UE B selects resource unit 10. In addition, UE C may also reselect resources. For example, the SCI sent by UE C may include a frequency domain offset field. The frequency domain offset field includes fifth indication information. The fifth indication information may not indicate whether the resource unit selected by UE C is located in the first direction or the second direction of resource unit 4. For example, the fifth indication information indicates that the frequency domain offset is 4. For example, the first resource set is Fig. 6A or Figure 6B As shown, it can be seen that if 4 resource units are offset in the direction of increasing the value of F based on resource unit 4, the range of the first resource set will be exceeded. Therefore, when the range of the first resource set is exceeded, the frequency domain offset can be calculated again from the frequency domain unit corresponding to the smallest F in the first resource set. Then, the receiving end of the SCI can determine that UE C selects resource unit 1. Among them, each SCI is sent in the resource pool ( Fig.11A For example, UE1, UE2 and UE3 are configured with the same resource pool, and the resource unit is located in a first resource set, which has no intersection with the resource pool.

[0156] Optionally, if the first information does not indicate the time domain offset, the first information may not include the fourth indication information, and the receiving end of the first information does not need to determine the resources selected by the first UE based on the fourth indication information. Alternatively, even if the first information does not indicate the time domain offset, the first information may include the fourth indication information, but the value of the fourth indication information at this time may be a default value, and the receiving end of the first information may determine that the fourth indication information is an invalid value based on the default value, or determine that the first information does not indicate the time domain offset. The relationship between the frequency domain offset and the fifth indication information is similar.

[0157] Optionally, whether the UE selects resources in the first resource set according to the identifier or not according to the identifier can be indicated by a network device or a UE, or preconfigured in the UE, or predefined by a protocol. For example, the network device indicates that the first information may include sixth indication information. When the sixth indication information is a first value, it may indicate that the index of the resource unit is determined according to the identifier, or indicates that the index of the resource unit is determined according to the identifier, or indicates that the index of the resource unit to which the first resource belongs is determined according to the first identifier; when the sixth indication information is a second value or is not the first value, it may indicate that the index of the resource unit is not determined according to the identifier, or indicates that the index of the resource unit is not determined according to the identifier, or indicates that the index of the resource unit to which the first resource belongs is not determined according to the first identifier.

[0158] Alternatively, when the first information includes the sixth indication information, it may indicate that the index of the resource unit is determined according to the identifier, or indicate that the index of the resource unit is determined according to the identifier, or indicate that the index of the resource unit to which the first resource belongs is determined according to the first identifier; when the first information does not include the sixth indication information, it may indicate that the index of the resource unit is not determined according to the identifier, or indicate that the index of the resource unit is not determined according to the identifier, or indicate that the index of the resource unit to which the first resource belongs is not determined according to the first identifier.

[0159] Alternatively, the sixth indication information may not be included in the first information, but may be included in other information, and there is no limitation on this.

[0160] Regardless of the above indication method used by the first information to indicate the first resource, optionally, the first information can also indicate a time window for sending a beam measurement result, and the beam measurement result can be obtained by measuring the first reference signal by the receiving end of the first information (for example, the second UE). For example, the first reference signal can be used for beam management, or the receiving end of the first reference signal (for example, the second UE) determines the communication beam between the first UE and the second UE according to the first reference signal. After receiving the first reference signal, the second UE can measure the first reference signal to obtain the beam measurement result. The second UE can send the beam measurement result to the first UE, and the first information can indicate the time window for sending the beam measurement result, so that the first UE can receive the beam measurement result within the time window, and the second UE can also send the beam measurement result within the time window, thereby improving the success rate of sending the beam measurement result, and also making it unnecessary for the first UE to continuously detect the beam measurement result, so as to save the power consumption of the first UE. The time window may be located within the time domain resources included in the first resource set, or the time window may be located outside the first resource set; the time window may be located within one or more resource pools in the first BWP (for example, located within the first resource pool of the first UE and / or located within the resource pools of other UEs), or located outside all resource pools included in the first BWP. Fig. 6A , Figure 6B , Fig. 9 , Fig.10 The time window is shown in the accompanying drawings. In these drawings, it is taken as an example that the time window is located in a certain resource pool.

[0161] For example, the first information may indicate the time window by adding a new field, and the new field may include, for example, a measurement window field and a window duration field. The measurement window may indicate the starting time domain position of the time window, for example, the indication method of the measurement window is similar to the aforementioned SFN field, and will not be described in detail. The window duration may indicate the duration of the time window.

[0162] Regardless of which indication method the first information adopts as above to indicate the first resource, optionally, the first information may also indicate the format of the time domain unit included in the first resource. The first resource may include one or more time domain units, wherein the formats of different time domain units may be the same or different. If the formats of different time domain units are the same, the first information indicates the format of any one of the time domain units; if the formats of different time domain units are different, the first information indicates the format of each time domain unit. Among them, the format of a time domain unit may indicate which sub-time domain units in the time domain unit are used to send reference signals. For example, the format of a time domain unit indicates the role of each sub-time domain unit in the time domain unit. Optionally, all sub-time domain units in a time domain unit are used to send reference signals; or, in addition to the sub-time domain unit used to send the reference signal, a time domain unit also includes a sub-time domain unit as a gap (GAP). For example, the first reference signal includes one or more reference signals, and a time domain unit included in the first resource can be used to send at least one reference signal of the one or more reference signals. Among them, in the at least one reference signal, the beam directions corresponding to different reference signals may be the same or different. If different reference signals correspond to different beam directions, the time domain unit may include a sub-time domain unit for sending the reference signal. In addition, a sub-time domain unit serving as a GAP may be included between the sub-time domain units used to send reference signals corresponding to two different beam directions so that the UE can switch the beam direction.

[0163] Optionally, the first resource may be a periodic resource, for example, the first information may also indicate a period of the first resource.

[0164] S504: The first UE sends a first reference signal in the first resource. Correspondingly, the second UE receives the first reference signal in the first resource.

[0165] Among them, if the first reference signal is a unicast signal, the second UE can receive the first reference signal; or, if the first reference signal is a broadcast signal or a multicast signal, the second UE is one of the UEs receiving the first reference signal, and in addition to the second UE, there may be other UEs receiving the first reference signal.

[0166] The first reference signal is used, for example, for beam management, or for the second UE to determine the communication beam between the first UE and the first UE, or may have other uses. For example, if the first reference signal is used for beam management or for determining the communication beam between the first UE and the first UE, the second UE may measure the first reference signal after receiving the first reference signal to obtain a beam measurement result. The beam measurement result may be represented, for example, by RSRP or other parameters. Among them, if the first reference signal is used for beam scanning, the beam measurement result may also be referred to as a beam scanning result, etc., without any limitation on the name.

[0167] Optionally, the method may further include S505, the second UE sends the beam measurement result to the first UE, and correspondingly, the first UE receives the beam measurement result. For example, if the first information further indicates a time window for sending the beam measurement result, the second UE may send the beam measurement result to the first UE within the time window, and the first UE may also receive the beam measurement result within the time window. Figure 5 Take S505 in this example.

[0168] In summary, the embodiments of the present application provide a resource set for sending a reference signal, and the resources in the resource set can be used to send a reference signal. It can be understood that the resources in the resource set can be used to send a reference signal and are not used to send data (such as PSSCH), so that the data and the reference signal may not be sent in the same resource, thereby reducing the impact of the reference signal on the data reception quality. For example, in the time domain unit where the PSSCH is located, AGC can still be implemented through the first symbol. Since the time domain unit does not include a reference signal, the transmission power in the time domain unit remains roughly unchanged. The AGC of the first symbol can cover the overall receiving power of the time slot, thereby improving the receiving quality of the PSSCH at the receiving end.

[0169] Fig.12 A schematic diagram of the structure of a communication device provided in an embodiment of the present application is given. The communication device 1200 may be Figure 5 The first UE or the circuit system of the first UE described in the embodiment shown is used to implement the method corresponding to the first UE in the above method embodiment. Alternatively, the communication device 1200 may be Figure 5 The second UE or the circuit system of the second UE is used to implement the method corresponding to the second UE in the above method embodiment. For example, one circuit system is a chip system.

[0170] The communication device 1200 includes at least one processor 1201. The processor 1201 can be used for internal processing of the device to implement certain control processing functions. Optionally, the processor 1201 includes instructions. Optionally, the processor 1201 can store data. Optionally, different processors can be independent devices, can be located in different physical locations, and can be located on different integrated circuits. Optionally, different processors can be integrated into one or more processors, for example, integrated on one or more integrated circuits.

[0171] Optionally, the communication device 1200 includes one or more memories 1203 for storing instructions. Optionally, data may also be stored in the memory 1203. The processor and the memory may be provided separately or integrated together.

[0172] Optionally, the communication device 1200 includes a communication line 1202 and at least one communication interface 1204. Since the memory 1203, the communication line 1202 and the communication interface 1204 are all optional, Fig.12 Indicated by dotted lines.

[0173] Optionally, the communication device 1200 may further include a transceiver and / or an antenna. The transceiver may be used to send information to other devices or receive information from other devices. The transceiver may be referred to as a transceiver, a transceiver circuit, an input / output interface, etc., and is used to implement the transceiver function of the communication device 1200 through an antenna. Optionally, the transceiver includes a transmitter and a receiver. Exemplarily, the transmitter may be used to generate a radio frequency signal from a baseband signal, and the receiver may be used to convert the radio frequency signal into a baseband signal.

[0174] The processor 1201 may include a general-purpose central processing unit (CPU), a microprocessor, an application specific integrated circuit (ASIC), or one or more integrated circuits for controlling the execution of the program of the present application.

[0175] The communication link 1202 may include a pathway to transmit information between the above-mentioned components.

[0176] The communication interface 1204 uses any transceiver-like device for communicating with other devices or communication networks, such as Ethernet, radio access network (RAN), wireless local area networks (WLAN), wired access networks, etc.

[0177] The memory 1203 may be a read-only memory (ROM) or other types of static storage devices that can store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that can store information and instructions, or an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical disc, laser disc, optical disc, digital versatile disc, Blu-ray disc, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto. The memory 1203 may exist independently and be connected to the processor 1201 via the communication line 1202. Alternatively, the memory 1203 may also be integrated with the processor 1201.

[0178] The memory 1203 is used to store computer-executable instructions for executing the solution of the present application, and the execution is controlled by the processor 1201. The processor 1201 is used to execute the computer-executable instructions stored in the memory 1203, thereby realizing Figure 5 The steps performed by the first UE or the second UE in the illustrated embodiment.

[0179] Optionally, the computer-executable instructions in the embodiments of the present application may also be referred to as application code, which is not specifically limited in the embodiments of the present application.

[0180] In a specific implementation, as an embodiment, the processor 1201 may include one or more CPUs, such as Fig.12 CPU0 and CPU1 in.

[0181] In a specific implementation, as an embodiment, the communication device 1200 may include multiple processors, such as Fig.12 1 and 1205. Each of these processors may be a single-CPU processor or a multi-CPU processor. A processor herein may refer to one or more devices, circuits, and / or processing cores for processing data (e.g., computer program instructions).

[0182] when Fig.12When the device shown is a chip, for example, a chip of the first UE or a chip of the second UE, the chip includes a processor 1201 (may also include a processor 1205), a communication line 1202 and a communication interface 1204, and optionally, the chip may include a memory 1203. Specifically, the communication interface 1204 may be an input interface, a pin or a circuit, etc. The memory 1203 may be a register, a cache, etc. The processor 1201 and the processor 1205 may be a general-purpose CPU, a microprocessor, an ASIC, or one or more integrated circuits for controlling the execution of the program of the communication method of any of the above embodiments.

[0183] The embodiment of the present application can divide the functional modules of the device according to the above method example. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in the embodiment of the present application is schematic and is only a logical functional division. There may be other division methods in actual implementation. For example, in the case of dividing each functional module according to each function, Fig.13 A schematic diagram of a device is shown, and the device 1300 may be the first UE or the second UE involved in the above-mentioned various method embodiments, or a chip in the first UE or a chip in the second UE. The device 1300 includes a processing unit 1302 and a transceiver unit 1301.

[0184] It should be understood that the device 1300 can be used to implement the steps performed by the first UE or the second UE in the communication method of the embodiment of the present application, and the relevant features can refer to the above Figure 5 The embodiments shown will not be described in detail here.

[0185] Optional, Fig.13 The functions / implementation processes of the transceiver unit 1301 and the processing unit 1302 can be Fig.12 The processor 1201 in the embodiment calls the computer execution instruction stored in the memory 1203 to implement. Or, Fig.13 The function / implementation process of the processing unit 1302 in Fig.12 The processor 1201 in the embodiment calls the computer execution instruction stored in the memory 1203 to implement, Fig.13 The function / implementation process of the transceiver unit 1301 can be Fig.12 It is implemented by the communication interface 1204 in.

[0186] Optionally, when the device 1300 is a chip or a circuit, the function / implementation process of the transceiver unit 1301 can also be implemented by a pin or a circuit. Optionally, the transceiver unit 1301 may include a sending unit and / or a receiving unit, the sending unit is used to implement the sending function, and the receiving unit is used to implement the receiving function; or, the transceiver unit 1301 may be an integral module that can implement the sending function and / or the receiving function. Optionally, the transceiver unit 1301 may be implemented by a transceiver.

[0187] The present application also provides a computer-readable storage medium, which stores a computer program or instruction. When the computer program or instruction is executed, the method performed by the first UE or the second UE in the aforementioned method embodiment is implemented. In this way, the functions described in the above embodiments can be implemented in the form of software functional units and sold or used as independent products. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. Storage media include: various media that can store program codes, such as USB flash drives, mobile hard drives, ROM, RAM, magnetic disks, or optical disks.

[0188] The present application also provides a computer program product, which includes: a computer program code, when the computer program code is run on a computer, the computer executes the method executed by the first UE or the second UE in any of the aforementioned method embodiments.

[0189] An embodiment of the present application also provides a processing device, including a processor and an interface; the processor is used to execute the method executed by the first UE or the second UE involved in any of the above method embodiments.

[0190] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid state disk (SSD)), etc.

[0191] The various illustrative logic units and circuits described in the embodiments of the present application can be implemented or operated by a general-purpose processor, a digital signal processor (DSP), an ASIC, a field-programmable gate array (FPGA), or other programmable logic devices, discrete gates or transistor logic, discrete hardware components, or any combination of the above. The general-purpose processor can be a microprocessor, and optionally, the general-purpose processor can also be any conventional processor, controller, microcontroller or state machine. The processor can also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other similar configuration.

[0192] The steps of the method or algorithm described in the embodiments of the present application can be directly embedded in the hardware, the software unit executed by the processor, or the combination of the two. The software unit can be stored in RAM, flash memory, ROM, erasable programmable read-only memory (erasable programmable read-only memory, EPROM), EEPROM, register, hard disk, removable disk, CD-ROM or other storage media of any form in the art. Exemplarily, the storage medium can be connected to the processor so that the processor can read information from the storage medium and can write information to the storage medium. Optionally, the storage medium can also be integrated into the processor. The processor and the storage medium can be arranged in an ASIC, and the ASIC can be arranged in a terminal device. Optionally, the processor and the storage medium can also be arranged in different components in the terminal device.

[0193] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0194] The contents of the various embodiments of the present application may refer to each other. If there is no special explanation and logical conflict, the terms and / or descriptions between different embodiments are consistent and can be referenced to each other. The technical features in different embodiments can be combined to form new embodiments according to their internal logical relationships.

[0195] It is understandable that in the embodiment of the present application, the first UE and / or the second UE may perform some or all of the steps in the embodiment of the present application, and these steps or operations are only examples. In the embodiment of the present application, other operations or variations of various operations may also be performed. In addition, the various steps may be performed in different orders presented in the embodiment of the present application, and it is possible that not all operations in the embodiment of the present application need to be performed.

Claims

1. A communication method, characterized in that: Applied to a first terminal device, the method includes: Determine a first resource in a resource selection window in a first resource set, where the first resource is used to send a first sidelink reference signal, and the first resource set is a dedicated resource set for the sidelink reference signal; Sending first information to a second terminal device, where the first information is used to indicate the first resource; The first sidelink reference signal is sent on the first resource.

2. The method according to claim 1, characterized in that The first sidelink reference signal is used by the second terminal device to determine a communication beam between the first terminal device and the second terminal device.

3. The method according to claim 1 or 2, characterized in that: The first resource includes a first sub-resource and a second sub-resource, and the first information includes first indication information and second indication information, the first indication information is used to indicate the time domain resource position of the first sub-resource, and the second indication information is used to indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource.

4. The method according to claim 3, characterized in that The first indication information is carried in a system frame number SFN or a direct frame number DFN, and the SFN or the DFN is used to indicate a time domain position of the first sub-resource; The second indication information is carried in a time offset field, and the time offset field is used to indicate a time interval between a time domain resource of the first sub-resource and a time domain resource of the second sub-resource.

5. The method according to any one of claims 1 to 4, characterized in that: The first resource is a periodic resource, and the first information is also used to indicate the period of the first resource.

6. The method according to any one of claims 1 to 5, characterized in that: The first information includes third indication information, and the third indication information is used to indicate a starting frequency domain position of a frequency domain resource of the first resource.

7. The method according to claim 6, characterized in that The third indication information is further used to indicate the number of frequency domain units occupied by the first resource.

8. The method according to claim 6 or 7, characterized in that: The first information is included in first sidelink control information SCI or medium access control MAC control element CE.

9. The method according to claim 1 or 2, characterized in that: The first information is used to indicate an index of a resource unit to which the first resource belongs, wherein the first resource set includes multiple resource units, and each resource unit in the multiple resource units corresponds to an index.

10. The method according to claim 9, characterized in that The index of the resource unit to which the first resource belongs is determined according to a first identifier in the first information, where the first identifier is a source identifier or a destination identifier of transmitted data, or is an identifier of the first reference signal.

11. The method according to claim 9, characterized in that The index of the resource unit to which the first resource belongs is indicated by the first identifier in the first information, and the fourth indication information and / or the fifth indication information in the first information, the fourth indication information is used to indicate the time domain offset, the time domain offset is the time domain offset of the first resource relative to the resource unit corresponding to the first identifier, and the fifth indication information is used to indicate the frequency domain offset, the frequency domain offset is the frequency domain offset of the first resource relative to the resource unit corresponding to the first identifier, wherein the fourth indication information includes information for indicating that the time domain offset is located before or after the first resource in the time domain; The first identifier is a source identifier or a destination identifier of transmitted data, or an identifier of the first reference signal.

12. The method according to claim 11, characterized in that The method further comprises: Second sidelink control information is received, and a resource unit determined according to the second sidelink control information is the same as the resource unit corresponding to the first identifier.

13. The method according to any one of claims 9 to 12, characterized in that: The first information also includes sixth indication information, and when the sixth indication information is a first value, it indicates that the index of the resource unit to which the first resource belongs is determined according to the first identifier.

14. The method according to any one of claims 9 to 13, characterized in that: The method further comprises: First configuration information is obtained, where the first configuration information is used to configure the first resource set, wherein the first configuration information includes mapping relationship information between positions and indexes of the multiple resource units.

15. The method according to any one of claims 1 to 14, characterized in that: The first sidelink reference signal includes multiple sidelink reference signals, and at least one sub-time domain unit in a time domain unit included in the first resource is used to send part or all of the multiple sidelink reference signals, and the beam directions corresponding to the sidelink reference signals carried by different sub-time domain units in the at least one sub-time domain unit are the same or different.

16. The method according to any one of claims 1 to 15, characterized in that: The first reference signal is a sidelink SL channel state information reference signal CSI-RS and / or a SL demodulation reference signal DMRS.

17. A communication method, characterized in that: Applied to a second terminal device, the method includes: receiving first information, where the first information is used to indicate a first resource, the first resource is used to send a first reference signal, the first resource belongs to a first resource set, and the first resource set is a resource set used to send a reference signal; The first sidelink reference signal is received on the first resource.

18. The method according to claim 17, characterized in that The method further comprises: A communication beam between the first terminal device and the second terminal device is determined based on the first sidelink reference signal.

19. The method according to claim 17 or 18, characterized in that The first resource includes a first sub-resource and a second sub-resource, and the first information includes first indication information and second indication information, the first indication information is used to indicate the time domain resource position of the first sub-resource, and the second indication information is used to indicate the time interval between the time domain resource of the first sub-resource and the time domain resource of the second sub-resource.

20. The method according to claim 19, characterized in that The first indication information is carried in a SFN or a DFN, where the SFN or the DFN is used to indicate a time domain position of the first sub-resource; The second indication information is carried in a time offset field, and the time offset field is used to indicate a time interval between a time domain resource of the first sub-resource and a time domain resource of the second sub-resource.

21. The method according to any one of claims 17 to 20, characterized in that: The first resource is a periodic resource, and the first information is also used to indicate the period of the first resource.

22. The method according to any one of claims 17 to 21, characterized in that: The first information includes third indication information, and the third indication information is used to indicate a starting frequency domain position of a frequency domain resource of the first resource.

23. The method according to claim 22, characterized in that The third indication information is further used to indicate the number of frequency domain units occupied by the first resource.

24. The method according to claim 22 or 23, characterized in that The first information is included in a first SCI or MAC CE.

25. The method according to claim 17 or 18, characterized in that The first information is used to indicate an index of a resource unit to which the first resource belongs, wherein the first resource set includes multiple resource units, and each resource unit in the multiple resource units corresponds to an index.

26. The method according to claim 25, characterized in that The index of the resource unit to which the first resource belongs is determined according to a first identifier in the first information, where the first identifier is a source identifier or a destination identifier of transmitted data, or is an identifier of the first reference signal.

27. The method according to claim 25, characterized in that The index of the resource unit to which the first resource belongs is indicated by the first identifier in the first information, and the fourth indication information and / or the fifth indication information in the first information, the fourth indication information is used to indicate the time domain offset, the time domain offset is the time domain offset of the first resource relative to the resource unit corresponding to the first identifier, and the fifth indication information is used to indicate the frequency domain offset, the frequency domain offset is the frequency domain offset of the first resource relative to the resource unit corresponding to the first identifier, wherein the fourth indication information includes information for indicating that the time domain offset is located before or after the first resource in the time domain; The first identifier is a source identifier or a destination identifier of transmitted data, or an identifier of the first reference signal.

28. The method according to any one of claims 25 to 27, characterized in that: The first information also includes sixth indication information, and when the sixth indication information is a first value, it indicates that the index of the resource unit to which the first resource belongs is determined according to the first identifier.

29. The method according to any one of claims 25 to 28, characterized in that: The method further comprises: First configuration information is obtained, where the first configuration information is used to configure the first resource set, wherein the first configuration information includes mapping relationship information between positions and indexes of the multiple resource units.

30. The method according to any one of claims 17 to 29, characterized in that: The first sidelink reference signal includes multiple sidelink reference signals, and at least one sub-time domain unit in a time domain unit included in the first resource is used to send part or all of the multiple sidelink reference signals, and the beam directions corresponding to the sidelink reference signals carried by different sub-time domain units in the at least one sub-time domain unit are the same or different.

31. The method according to any one of claims 17 to 30, characterized in that: The first reference signal is SLCSI-RS and / or SL DMRS.

32. A communication device, characterized in that: The communication device comprises a processing unit and a transceiver unit, wherein the processing unit is coupled to the transceiver unit to execute the method according to any one of claims 1 to 16, or execute the method according to any one of claims 17 to 31.

33. A communication device, characterized in that: The communication device includes a processor and a memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the communication device performs the method as described in any one of claims 1 to 16, or the communication device performs the method as described in any one of claims 17 to 31.

34. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and when the computer program is run on a computer, the computer is caused to execute the method according to any one of claims 1 to 16, or the computer is caused to execute the method according to any one of claims 17 to 31.

35. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is run on a computer, the computer is caused to execute the method according to any one of claims 1 to 16, or the computer is caused to execute the method according to any one of claims 17 to 31.

36. A chip system, characterized in that: The chip system comprises: A processor and an interface, wherein the processor is used to call and run instructions from the interface, and when the processor executes the instructions, the method according to any one of claims 1 to 17 is implemented, or the method according to any one of claims 17 to 31 is implemented.

37. A communication system, characterized in that: The communication system comprises a first terminal device and a second terminal device, wherein: The first terminal device is used to execute the method according to any one of claims 1 to 16; The second terminal device is used to execute the method according to any one of claims 17 to 31.

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