Method, device and equipment for determining straight-through link resources working in unauthorized frequency band

Abstract

The invention discloses a method, a device and equipment for determining straight-through link resources working in an unauthorized frequency band. The method comprises the following steps: acquiring initial information by first terminal equipment; determining a candidate resource set based on the initial information; and performing resource exclusion on the candidate resource set to obtain an available resource set. According to the method, when the Sidelink resources are determined, the characteristics of the SL-U are fully considered, the resource selection process is improved, the available resource set suitable for the SL-U can be determined, preparation work is made for determining reasonable resources for SL-U communication based on the available resource set, and effective SL-U communication between terminal equipment becomes possible.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a method, apparatus and device for determining sidelink resources operating in an unlicensed frequency band. Background Art

[0002] Sidelink is one of the communication methods used between terminal devices. When a terminal device needs to communicate with other terminal devices via Sidelink, it needs to select Sidelink transmission resources first, and then use the selected Sidelink transmission resources to achieve Sidelink-based communication with other terminal devices. The current Sidelink resource selection mechanism is usually for licensed frequency bands.

[0003] However, the 3rd Generation Partnership Project (3GPP) introduced the Sidelink Operation on Unlicensed Spectrum (SL-U) which is a direct link working in the unlicensed spectrum. Compared with the Sidelink communication in the licensed spectrum, the terminal equipment working in the unlicensed spectrum can use any available spectrum without authorization. However, considering the new features of SL-U, the Sidelink resource selection mechanism applicable to the licensed spectrum, a dedicated spectrum, cannot be directly reused.

[0004] Based on this, in order to realize SL-U-based communication, ensure transmission efficiency and improve transmission reliability, it is urgent to provide a resource determination solution suitable for SL-U. Summary of the invention

[0005] The present application provides a method, apparatus and device for determining Sidelink resources operating in an unlicensed frequency band. The characteristics of SL-U are fully considered in the Sidelink resource determination mechanism, and preparations are made for selecting reasonable SL-U resources, making it possible to use SL-U for effective communication.

[0006] In a first aspect, the present application provides a method for determining a direct link resource operating in an unlicensed frequency band, characterized in that it is applied to a first terminal device, including:

[0007] Get initial information;

[0008] Based on the initial information, determining a set of candidate resources;

[0009] The candidate resource set is excluded to obtain an available resource set.

[0010] Optionally, the method may further include:

[0011] A target resource is selected from the set of available resources.

[0012] Optionally, the initial information includes at least one of the following information:

[0013] Available resource block set (ResourceBlockset, RBset);

[0014] Unavailable RBset;

[0015] RBsets with consecutive ListenBeforeTalk (LBT) failures;

[0016] Time information corresponding to RBsets with consecutive LBT failures;

[0017] The number of RBsets occupied by Physical Sidelink Control Channel (PSCCH) and / or Physical Sidelink Shared Channel (PSSCH) transmissions within a time unit;

[0018] RBsets occupied by PSCCH and / or PSSCH transmissions within a time unit;

[0019] The number of subchannels occupied by PSCCH and / or PSSCH transmissions in one time unit;

[0020] The number of subchannels occupied by PSCCH and / or PSSCH transmission in one RBset in one time unit;

[0021] The starting physical resource block (PRB) of the resource pool.

[0022] Optionally, the available RBset satisfies at least one of the following conditions:

[0023] The available RBset is a continuous RBset in the frequency domain;

[0024] The available RBset does not include a RBset with consecutive LBT failures;

[0025] The number of RBsets in any combination of consecutive RBsets in the available RBsets is greater than or equal to the number of RBsets occupied by PSSCH and / or PSCCH transmission.

[0026] Optionally, the RBset occupied by PSCCH and / or PSSCH transmission within the one time unit satisfies at least one of the following conditions:

[0027] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit are continuous RBsets in the frequency domain;

[0028] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit do not include RBsets with continuous LBT failures.

[0029] Optionally, the resources in the candidate resource set need to meet at least one of the following conditions:

[0030] Located in one of the time units in the time domain;

[0031] The frequency domain includes a first number of RBsets, wherein each RBset occupies a second number of subchannels.

[0032] Optionally, the first quantity and / or the second quantity needs to satisfy at least one of the following conditions:

[0033] The product of the first number and the second number is equal to the number of subchannels occupied by PSCCH / PSSCH transmission;

[0034] The second number of sub-channels are continuous sub-channels;

[0035] Indexes of the second number of sub-channels occupied by different RBsets in the first number of RBsets are the same;

[0036] The first number of RBsets are continuous RBsets;

[0037] The first number of RBsets does not include any unavailable RBset in the initial information;

[0038] The first number of RBsets does not include any RBset with continuous LBT failure in the initial information;

[0039] The first number is equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission in a time unit in the initial information;

[0040] The first number of RBsets are RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information.

[0041] Optionally, determining a candidate resource set based on the initial information includes:

[0042] Based on at least one of the initial information, the target time and the target frequency domain, the candidate resource set is determined, the resources in the candidate resource set belong to the target time in the time domain, and the resources in the candidate resource set belong to the target frequency domain in the frequency domain.

[0043] Optionally, the target frequency domain satisfies at least one of the following conditions:

[0044] The target frequency domain is an RBset occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information;

[0045] The target frequency domain is a third number of continuous RBsets in the resource pool, and the third number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0046] The target frequency domain is a set of all target type RBsets in the resource pool, and the target type RBset set includes a fourth number of continuous RBsets, and the fourth number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0047] Optionally, the target frequency domain resources do not include an RB set in at least one of the following situations:

[0048] RBsets with consecutive LBT failures in the initial information;

[0049] A fifth number of consecutive RBsets, where the fifth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0050] An independent RBset, where the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0051] Optionally, excluding resources from the candidate resource set to obtain an available resource set includes:

[0052] From the candidate resource set, target class candidate resources are excluded to obtain the available resource set, and the target class candidate resources are located in the target RBset.

[0053] Optionally, the target RBset satisfies at least one of the following conditions:

[0054] The target RBset is the RBset with consecutive LBT failures in the initial information;

[0055] The target RBset is an unavailable RBset in the initial information;

[0056] The target RBset is a sixth number of consecutive RBsets, where the sixth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0057] The target RBset is an independent RBset, and the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0058] Optionally, a ratio of the number of resources in the available resource set to the number of resources in the first resource set is greater than or equal to a first threshold,

[0059] The first resource set is any one of the following:

[0060] The first resource set is all candidate resources in the resource selection window;

[0061] The first resource set is all candidate resources in the resource selection window except the target class candidate resources.

[0062] Optionally, the method further comprises:

[0063] A channel busy rate (Channel Busy Ratio, CBR) is obtained, where the CBR is the ratio of the number of sub-channels whose received signal strength indicator (Received Signal Strength Indicator, RSSI) exceeds the second threshold to the number of all sub-channels in the resource selection window.

[0064] Optionally, the RSSI is defined in any one of the following ways:

[0065] The RSSI is the linear average of all received powers on orthogonal frequency division multiplexing OFDM symbols except the start symbol configured for PSCCH and PSSCH in a time slot;

[0066] The RSSI is the maximum value of at least two values ​​among a first value, a second value, and a third value, wherein the first value is the linear average value of the received power on all symbols between the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; the second value is the linear average value of the received power on all symbols after the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; and the third value is the linear average value of the received power on all symbols except the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot.

[0067] Optionally, the frequency domain range of the target measurement window is at least one of the following:

[0068] The frequency domain scope of the resource pool;

[0069] RBsets in the resource pool except the unavailable RBset in the initial information;

[0070] RBsets in the resource pool except the RBset with consecutive LBT failures in the initial information.

[0071] In a second aspect, the present application further provides a device for determining a direct link resource operating in an unlicensed frequency band, which is applied to a first terminal device, including:

[0072] An acquisition unit, used for acquiring initial information;

[0073] A determination unit, configured to determine a candidate resource set based on the initial information;

[0074] The obtaining unit is used to exclude resources from the candidate resource set to obtain an available resource set.

[0075] Optionally, the device further comprises:

[0076] The selection unit is used to select a target resource from the available resource set.

[0077] Optionally, the initial information includes at least one of the following information:

[0078] Available RBsets;

[0079] Unavailable RBset;

[0080] RBset with consecutive LBT failures;

[0081] Time information corresponding to RBsets with consecutive LBT failures;

[0082] The number of RBsets occupied by PSCCH and / or PSSCH transmissions in one time unit;

[0083] RBsets occupied by PSCCH and / or PSSCH transmissions within a time unit;

[0084] The number of subchannels occupied by PSCCH and / or PSSCH transmissions in one time unit;

[0085] The number of subchannels occupied by PSCCH and / or PSSCH transmission in one RBset in one time unit;

[0086] The starting PRB of the resource pool.

[0087] Optionally, the available RBset satisfies at least one of the following conditions:

[0088] The available RBset is a continuous RBset in the frequency domain;

[0089] The available RBset does not include a RBset with consecutive LBT failures;

[0090] The number of RBsets in any combination of consecutive RBsets in the available RBsets is greater than or equal to the number of RBsets occupied by PSSCH and / or PSCCH transmission.

[0091] Optionally, the RBset occupied by PSCCH and / or PSSCH transmission within the one time unit satisfies at least one of the following conditions:

[0092] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit are continuous RBsets in the frequency domain;

[0093] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit do not include RBsets with continuous LBT failures.

[0094] Optionally, the resources in the candidate resource set need to meet at least one of the following conditions:

[0095] Located in one of the time units in the time domain;

[0096] The frequency domain includes a first number of RBsets, wherein each RBset occupies a second number of subchannels.

[0097] Optionally, the first quantity and / or the second quantity needs to satisfy at least one of the following conditions:

[0098] The product of the first number and the second number is equal to the number of subchannels occupied by PSCCH / PSSCH transmission;

[0099] The second number of sub-channels are continuous sub-channels;

[0100] Indexes of the second number of sub-channels occupied by different RBsets in the first number of RBsets are the same;

[0101] The first number of RBsets are continuous RBsets;

[0102] The first number of RBsets does not include any unavailable RBset in the initial information;

[0103] The first number of RBsets does not include any RBset with continuous LBT failure in the initial information;

[0104] The first number is equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission in a time unit in the initial information;

[0105] The first number of RBsets are RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information.

[0106] Optionally, the determining unit is specifically configured to:

[0107] Based on at least one of the initial information, the target time and the target frequency domain, the candidate resource set is determined, the resources in the candidate resource set belong to the target time in the time domain, and the resources in the candidate resource set belong to the target frequency domain in the frequency domain.

[0108] Optionally, the target frequency domain satisfies at least one of the following conditions:

[0109] The target frequency domain is an RBset occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information;

[0110] The target frequency domain is a third number of continuous RBsets in the resource pool, and the third number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0111] The target frequency domain is a set of all target type RBsets in the resource pool, and the target type RBset set includes a fourth number of continuous RBsets, and the fourth number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0112] Optionally, the target frequency domain resources do not include an RB set in at least one of the following situations:

[0113] RBsets with consecutive LBT failures in the initial information;

[0114] A fifth number of consecutive RBsets, where the fifth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0115] An independent RBset, where the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0116] Optionally, the obtaining unit is specifically used to:

[0117] From the candidate resource set, target class candidate resources are excluded to obtain the available resource set, and the target class candidate resources are located in the target RBset.

[0118] Optionally, the target RBset satisfies at least one of the following conditions:

[0119] The target RBset is the RBset with consecutive LBT failures in the initial information;

[0120] The target RBset is an unavailable RBset in the initial information;

[0121] The target RBset is a sixth number of consecutive RBsets, where the sixth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0122] The target RBset is an independent RBset, and the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0123] Optionally, a ratio of the number of resources in the available resource set to the number of resources in the first resource set is greater than or equal to a first threshold,

[0124] The first resource set is any one of the following:

[0125] The first resource set is all candidate resources in the resource selection window;

[0126] The first resource set is all candidate resources in the resource selection window except the target class candidate resources.

[0127] Optionally, the device further comprises:

[0128] The calculation unit is used to obtain a CBR, where the CBR is the ratio of the number of sub-channels whose RSSI exceeds the second threshold to the number of all sub-channels in the resource selection window.

[0129] Optionally, the RSSI is defined in any one of the following ways:

[0130] The RSSI is the linear average of all received powers on orthogonal frequency division multiplexing OFDM symbols configured for PSCCH and PSSCH in a time slot except the start symbol, and the start symbol may be 1 symbol or 2 symbols;

[0131] The RSSI is the maximum value of at least two values ​​among a first value, a second value, and a third value, wherein the first value is the linear average value of the received power on all symbols between the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; the second value is the linear average value of the received power on all symbols after the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; and the third value is the linear average value of the received power on all symbols except the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot.

[0132] Optionally, the frequency domain range of the target measurement window is at least one of the following:

[0133] The frequency domain scope of the resource pool;

[0134] RBsets in the resource pool except the unavailable RBset in the initial information;

[0135] RBsets in the resource pool except the RBset with consecutive LBT failures in the initial information.

[0136] In a third aspect, the present application further provides a terminal device, the terminal device comprising a processor and a memory:

[0137] The memory is used to store programs;

[0138] The processor is used to execute the method provided in the first aspect according to the program.

[0139] In a fourth aspect, the present application further provides a storage medium, wherein the storage medium is used to store a program, and the program runs on a processor to execute the method provided in the first aspect above.

[0140] It can be seen that this application has the following beneficial effects:

[0141] The present application provides a method for determining direct link resources working in an unlicensed frequency band. If a first terminal device has a need to communicate with a second terminal device via SL-U, the method can be executed to select transmission resources based on SL-U. In the method, first, the first terminal device obtains initial information; then, the first terminal device determines a candidate resource set based on the initial information; then, the first terminal device excludes resources from the candidate resource set to obtain an available resource set. In this way, the first terminal device can select a target resource from the available resource set, so that the first terminal device can perform SL-U communication with the second terminal device based on the target resource. It can be seen that this method overcomes the problem of being unable to directly use the Sidelink resource selection scheme for the licensed frequency band, fully considers the characteristics of SL-U in the resource determination process, and provides a method for determining an available resource set suitable for SL-U, which prepares for selecting target transmission resources and makes it possible for terminal devices to use SL-U for effective communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0142] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0143] Figure 1 Schematic diagram of the corresponding relationship between subchannels, IRBs and PRBs;

[0144] Figure 2 A flowchart of a method for determining direct link resources operating in an unlicensed frequency band in an embodiment of the present application;

[0145] Figure 3 A schematic diagram of RBset in the initial information in an embodiment of the present application;

[0146] Figure 4 A schematic diagram of time information of continuous LBT failures in an embodiment of the present application;

[0147] Figure 5 A schematic diagram of candidate single time slot resources in an embodiment of the present application;

[0148] Figure 6 Another schematic diagram of candidate single time slot resources in an embodiment of the present application;

[0149] Figure 7 A schematic diagram of symbols in a time slot according to an embodiment of the present application;

[0150] Figure 8Schematic diagram of the structure of a device 800 for determining direct link resources in an unlicensed frequency band according to an embodiment of the present application;

[0151] Fig. 9 It is a structural diagram of a terminal device 900 in an embodiment of the present application. DETAILED DESCRIPTION

[0152] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It is understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application. In addition, it should be noted that, for ease of description, only the parts related to the present application are shown in the accompanying drawings, not all structures.

[0153] Terminal devices working in unlicensed spectrum need to meet the restrictions of occupied channel bandwidth (OCB) and power spectrum density (PSD). Therefore, the interlaced resource block (IRB) structure is introduced in the new radio unlicensed spectrum (NR-U) working in unlicensed spectrum. In the SL-U mechanism, the transmission of PSCCH and PSSCH supports the IRB structure. In addition, the concept of subchannel in R16 / R17 is adopted in the SL-U system based on the IRB structure. The subchannel is the minimum granularity of PSSCH transmission. The subchannel is defined as one or more IRBs. Therefore, the subchannel is no longer composed of continuous PRBs in the frequency domain. The R16 / R17 resource allocation mechanism is designed for subchannels based on continuous PRBs and is not applicable to the SL-U system based on IRBs.

[0154] The relationship between subchannels, IRBs, and PRBs in SL-U can be understood as follows: a subchannel is defined in an RBset, and a subchannel is equal to K IRBs, that is, a subchannel is equal to K IRBs in an RB set; the PRBs included in an IRB with index m can be expressed as {m+M, m+2M, m+3M, ...}, that is, an IRB includes multiple PRBs, and the interval between PRBs is M. Among them, for the case where the subcarrier spacing is 15 kilohertz (kHz), M is equal to 10, K can be equal to 1 or 2, and for the case where the subcarrier spacing is 30kHz, M is equal to 5, K can be equal to 1; m∈{0,1,…,M-1}. Taking M=5 as an example, the relationship between IRB, PRB, and subchannels can be seen, for example. Figure 1As shown, there is only one RBset in the resource pool, including 5 IRBs with indexes: 0, 1, 2, 3, 4, and the corresponding PRB indexes are: 0, 1, 2, 3, 4, ..., 48, 49. Then, if K=2, subchannel 0 includes IRB0 and IRB1 in the RBset, and subchannel 1 includes IRB2 and IRB3 in the RBset; if K=1, subchannel 0 includes IRB0 in the RBset, and subchannel 1 includes IRB1 in the RBset.

[0155] In order to ensure that SL-U can be widely used, an embodiment of the present application provides a resource determination method suitable for SL-U, in which the characteristics of SL-U are introduced, such as RBset for detecting continuous LBT failures, physical layer structure based on IRB, definition of sub-channels, etc., and the resource allocation mechanism of the direct link is improved, so that the resources in the determined available resource set are suitable for SL-U communication. In this method, first, the first terminal device obtains initial information; then, the first terminal device determines a candidate resource set based on the initial information; then, the first terminal device excludes resources from the candidate resource set to obtain an available resource set. If the first terminal device has a need to communicate with the second terminal device via SL-U, the above initial information can be configuration information of the resource pool and / or parameter information required for SL-U communication, etc.; moreover, after obtaining the available resource set, the target resource can also be selected from the available resource set, so that the first terminal device can perform SL-U communication with the second terminal device based on the target resource. It can be seen that this method overcomes the problem of not being able to directly use the Sidelink resource selection scheme for the authorized frequency band. It can fully consider the characteristics of SL-U in the resource determination process, and provides a method for determining the available resource set suitable for SL-U. It prepares for selecting the target transmission resources and makes it possible for terminal devices to use SL-U for effective communication.

[0156] It should be noted that the subject implementing the method for determining direct link resources working in an unlicensed frequency band may be a device for determining direct link resources working in an unlicensed frequency band provided in an embodiment of the present application, and the device for determining direct link resources working in an unlicensed frequency band may be carried in a terminal device or a functional module of a terminal device. The terminal device mentioned above may be any device capable of implementing the method for determining direct link resources working in an unlicensed frequency band in an embodiment of the present application, for example, the terminal device may be a smart phone, a vehicle-mounted terminal, etc.

[0157] It should be noted that when each terminal device has the need to communicate with other terminal devices via Sidelink, the terminal device can serve as the first terminal device in the embodiment of the present application, and take the other party as the second terminal device, execute the method provided in the embodiment of the present application, and determine the set of available resources that can select reasonable resources when communicating with the other party using SL-U.

[0158] To facilitate understanding of the specific implementation of the direct link resource selection method for working in an unlicensed frequency band provided in an embodiment of the present application, it will be described below with reference to the accompanying drawings.

[0159] Figure 2 A schematic diagram of a method for determining direct link resources in an unlicensed frequency band provided in an embodiment of the present application. Figure 2 As shown, the method can be applied to a first terminal device, and is suitable for determining a set of available resources for Sidelink communication with a second terminal device by the first terminal device when the first terminal device needs to communicate with the second terminal device via Sidelink.

[0160] like Figure 2 As shown, the method may include, for example, S101 to S103:

[0161] S101, obtaining initial information.

[0162] Initial information refers to the information required for the first terminal device and the second terminal device to perform SL-U communication, including but not limited to resource pool configuration information and / or transmission parameter information, etc. The initial information can be a high-level (media access control (MAC) layer or radio resource control (RRC) layer, etc.) configuration of the first terminal device, a base station configuration, a high-level indication, predefined or preconfigured.

[0163] As an example, the initial information may include at least one of the following information: (1) available RBset; (2) unavailable RBset; (3) RBset with continuous LBT failure; (4) time information corresponding to RBset with continuous LBT failure; (5) the number of RBsets occupied by PSCCH and / or PSSCH transmission within a time unit; (6) the RBsets occupied by PSCCH and / or PSSCH transmission within a time unit; (7) the number of subchannels occupied by PSCCH and / or PSSCH transmission within a time unit; (8) the number of subchannels occupied by PSCCH and / or PSSCH transmission within a time unit; (9) the starting PRB of the resource pool.

[0164] Optionally, the initial information may also include at least one of the following information: (10) resource pool; (11) layer 1 (Layer 1, L1) priority; (12) remaining service packet transmission delay; (13) resource reservation interval (or resource reservation cycle); (14) a set of resources that may be re-evaluated (Re-evaluation) and / or preempted (Pre-emption); (15) resource selection mechanism indication.

[0165] For (1) in the initial information, it can refer to the available RBset in the resource pool, or the frequency domain range of the resource selection window, or the available RBset in the resource selection window, or the available RBset for PSCCH and PSSCH transmission, that is, the definition of candidate resources, the initialization of candidate resource sets, the available resource sets, and the transmission resources of PSCCH and PSSCH need to be located in these RBsets. In particular, for multiple transmissions of a transport block (TransportBlock, TB), or a transmission and its subsequent scheduled transmissions, each transmission needs to be located in these RBsets. It should be noted that the RBset in (1) needs to be a RBset that is continuous in the frequency domain or indexed continuously.

[0166] In specific implementation, (1) can be determined by a high layer (e.g., MAC layer) of the first terminal device and sent to the physical layer of the first terminal device; or, (1) can also be determined by the physical layer of the first terminal device. Taking the high layer determining (1) as an example, for example, an RBset that satisfies at least one of the following conditions can be used as an available RBset: Condition 11, the available RBset is a continuous RBset in the frequency domain; Condition 12, the available RBset does not include RBsets with continuous LBT failures; Condition 13, the number of RBsets in any combination of continuous RBsets in the available RBset is greater than or equal to the number of RBsets required for PSSCH and / or PSCCH transmission (or, MAC protocol data unit (Protocol Data Unit, PDU)). In condition 11, the available RBset is a continuous RBset in the frequency domain, which can refer to the continuous index of the RBset. Here, "RBset" can also be expressed as "RBset(s)", indicating an RBset set, including one or more RBsets. If there are multiple RBsets, these multiple RBsets are required to be continuous in the frequency domain; or, the available RBset can also have only one RBset.

[0167] It is understandable that when the upper layer determines the available RBset, it needs to consider whether there is an RBset that detects continuous LBT failures, and the final effect is that the indicated RBset does not include the RBset that detects continuous LBT failures. Figure 3 As shown in FIG. 1 , RBset#3 and RBset#5 represent RBsets in which continuous LBT failures are detected. Therefore, the available RBsets indicated by the high layer may include: RBset#0, RBset#1, RBset#2, RBset#4, RBset#6, and RBset#7. If it is considered that the available RBsets can be used for PSCCH and / or PSSCH transmission, that is, the above condition 13 ( Figure 3 There are three combinations of any continuous RBsets, namely RBset#0+RBset#1+RBset#2, RBset#4 and RBset#6+RBset#7, that is, the combination of any continuous RBsets here represents the combination of the largest number of continuous RBsets, for example, RBset#0+RBset+1 cannot be called a combination of continuous RBsets), and the RBsets in the available RBsets need to be continuous. Assuming that PSCCH and / or PSSCH transmission requires 2 RBsets, the available RBsets determined by the high layer can be RBset#0, RBset#1, RBset#2, RBset#6 and RBset#7, among which RBset#0, RBset#1 and RBset#2 represent the first subset, RBset#6 and RBset#7 represent the second subset, and RBset#4 has only one RBset and does not constitute a continuous RBset with other RBsets. It cannot meet the transmission of PSCCH and / or PSSCH, so it is not included in the available RBset.

[0168] For (2) in the initial information, it can refer to an unavailable RBset in the resource pool, which is used to indicate an RBset that cannot be used in the resource selection process. (2) can also be described as: an unavailable RBset in the resource pool, or an RBset that is determined to be unavailable for the initialization resource set, or an RBset that cannot be used for PSCCH and / or PSSCH transmission.

[0169] For (3) in the initial information, it may refer to an RBset in the resource pool in which a continuous LBT failure (Consistent LBT failure) is detected, and the RBset may belong to an unavailable RBset.

[0170] For (4) in the initial information, at least one of the following may be included: the start time corresponding to the RBset with continuous LBT failure, the duration corresponding to the RBset with continuous LBT failure, or the end time corresponding to the RBset with continuous LBT failure. (3) and (4) may be combined to determine the unavailable RBset and the time period during which the RBset is unavailable. As an example, if the resource selection window determined by the first terminal device is as follows: Figure 4 As shown, the time domain includes [n+T1, n+T2], and the frequency domain includes RBset#0 and RBset#1. The RBset detected to have continuous LBT failure is RBset#1, the start time corresponding to the RBset with continuous LBT failure is n-10, and the duration corresponding to the continuous LBT failure is 20 time slots, that is, the end time is n+10. It can be determined that RBset#1 is unavailable in the time period from n+T1 to n+10 in the resource selection window.

[0171] For (5) in the initial information, for example, when the result of (5) is 2, it means that a single PSCCH and / or PSSCH transmission needs to be located in 2 RBsets, or it means that a single time slot candidate resource needs to be located in 2 RBsets, but the positions of the two RBsets may not be fixed, and may be RBset#0+RBset#1 in the resource pool, or RBset#1+RBset#2. In addition, the two RBsets also need to be continuous, that is, (5) can be expressed as the number of continuous RBsets occupied by the transmission of PSCCH and / or PSSCH in a time unit. (5) can mean that any transmission of a transport block (TransportBlock, TB) needs to occupy 2 RBsets, or that each transmission in the initial transmission and the scheduled PSCCH and / or PSSCH transmission needs to occupy 2 RBsets, or that the MAC PDU needs to occupy 2 RBsets.

[0172] In specific implementation, (5) can be determined by the high layer of the first terminal device and sent to the physical layer of the first terminal device; or, (5) can also be determined by the physical layer of the first terminal device. Taking the high-level determination of (5) as an example, the factors that can be considered in the RBset counted by (5) include at least one of the following: the total number of RBsets configured in the resource pool, the RBset in which continuous LBT failures are detected, the number of subchannels occupied by PSCCH and / or PSSCH transmissions, the number of subchannels occupied by PSCCH and / or PSSCH transmissions in one RBset, PSCCH and / or PSSCH transmissions occupying continuous RBsets, and the number of subchannels occupied by PSCCH and / or PSSCH transmissions in different RBsets used is the same and the subchannel indexes are the same. For example, still refer to Figure 3 As shown, PSCCH and / or PSSCH transmission occupies 4 subchannels and occupies at least 1 subchannel in one RBset. Therefore, PSCCH and / or PSSCH transmission is located in at most 4 RBsets. Considering that the number of subchannels occupied and the index are the same in different RBsets, and PSCCH and / or PSSCH transmission occupies continuous RBsets, it is determined that the number of RBsets in (5) can only be 1 or 2.

[0173] For (6) in the initial information, for example, when the result of (6) is RBset#1 and RBset#2, it can indicate that a single PSCCH and / or PSSCH transmission needs to be located in these two RBsets, or that a single time slot candidate resource needs to be located in these two RBsets, or that any transmission in a TB needs to be located in these two RBsets, or that the initial transmission and its reserved retransmission resources need to be located in these two RBsets, or that the transmission of MAC PDU needs to be located in these two RBsets, and these two RBsets need to be continuous.

[0174] In specific implementation, (6) can be determined by the high layer of the first terminal device and sent to the physical layer of the first terminal device; or, (6) can also be determined by the physical layer of the first terminal device. Taking the high layer determining (6) as an example, for example, the RBset that satisfies at least one of the following conditions can be used as the content of (6): Condition 21, the RBset occupied by PSCCH and / or PSSCH transmission in the said time unit is a continuous RBset in the frequency domain: Condition 22, the RBset occupied by PSCCH and / or PSSCH transmission in the said time unit does not include the RBset with continuous LBT failure. Condition 23, the number of RBsets occupied by PCCH and / or PSSCH transmission in the said time unit is equal to the number of RBsets required for PSCCH and / or PSSCH transmission. Condition 24: The number of RBsets in any continuous RBset combination of the RBsets occupied by PSCCH and / or PSSCH transmission in the said time unit is greater than or equal to the number of RBsets required for PSCCH and / or PSSCH transmission. In condition 21, RBset that is continuous in the frequency domain may refer to continuous RBset indexes. Here, "RBset" may also be expressed as "RBset(s)", indicating an RBset set, which includes one or more RBsets. If there are multiple RBsets, these multiple RBsets are required to be continuous in the frequency domain; or, there may be only one RBset available.

[0175] It is understandable that when the high-level layer determines the RBset in (6), it needs to consider: the total number of RBsets configured in the resource pool, the RBset in which continuous LBT failures are detected, the number of subchannels occupied by PSCCH and / or PSSCH transmissions, the number of subchannels occupied by PSCCH and / or PSSCH transmissions in one RBset, the number of consecutive RBsets occupied by PSCCH and / or PSSCH transmissions, and the number of subchannels occupied by PSCCH and / or PSSCH transmissions in different RBsets used and the same subchannel index. Figure 3As shown, PSCCH and / or PSSCH transmission occupies 4 subchannels and occupies at least 1 RBset in one RBset, that is, PSCCH and / or PSSCH transmission is located in at most 4 RBsets. In addition, considering that the number of subchannels occupied and the index in different RBsets are the same, and PSCCH and / or PSSCH transmission occupies continuous RBsets. When the number of RBsets occupied by PSCCH and / or PSSCH transmission can be 1, the (6) determined by the high layer includes: RBset#0, RBset#1, RBset#2, RBset#4, RBset#6 and RBset#7. When the number of RBsets occupied by PSCCH and / or PSSCH transmission can be 2, the (6) determined by the high layer includes: RBset#0+RBset#1, RBset#1+RBset#2, RBset#6+RBset#7, that is, the indicated RBset as a whole can be non-continuous, but any combination of continuous RBsets can meet the requirements of PSCCH and / or PSSCH transmission. In addition, the higher layer may also randomly select one from the above three combinations to indicate to the physical layer, such as RBset#0+RBset#1. In this case, it means that the RBset is continuous and can meet the PSCCH and / or PSSCH transmission requirements.

[0176] For (7) in the initial information, it can be described as the number of subchannels occupied by PSCCH and / or PSSCH transmission in a time slot in all used RBsets, or the number of subchannels occupied by a single PSCCH and / or PSSCH transmission in all used RBsets.

[0177] For (8) in the initial information, in one case, the subchannels occupied by PSCCH and / or PSSCH in each RBset may be continuous; or, in another case, the subchannels occupied by PSCCH and / or PSSCH in each RBset may be non-continuous.

[0178] It should be noted that in (5) to (8) of the initial information, the time unit may be a subframe, a time slot, a partial time slot, a symbol or a combination of multiple symbols.

[0179] It should be noted that in (5) to (8) of the initial information, "PSCCH and / or PSSCH transmission within a time unit" can also be understood or described as: a single PSCCH and / or PSSCH transmission, any PSCCH and / or PSSCH transmission in a TB, initial transmission and scheduled PSCCH and / or PSSCH transmission.

[0180] For (9) in the initial information, it can be described as the starting PRB in the first RBset in the resource pool, or, it can be described as the starting PRB of the first subchannel in the first RBset in the resource pool, or, it can be described as the starting PRB of the first subchannel in the resource pool, where the first subchannel refers to the lowest subchannel in the frequency domain, not the subchannel with the smallest index.

[0181] It should be noted that in order to determine the available RBset, the number of RBsets or the occupied RBset in the initial information, at least one of the following factors needs to be considered: the total number of RBsets configured in the resource pool, the RBset in which continuous LBT failures are detected, the number of subchannels occupied by PSCCH and / or PSSCH transmissions, the number of subchannels occupied by PSCCH and / or PSSCH transmissions in one RBset, continuous RBsets occupied by PSCCH and / or PSSCH transmissions, and the number of subchannels occupied by PSCCH and / or PSSCH transmissions in different RBsets used is the same and the subchannel indexes are the same.

[0182] For (10) in the initial information, it is used to indicate the scope of resource selection, and resource selection is performed in the resource pool. For (15) in the initial information, it can include full sensing, partial sensing, random resource selection, and any combination thereof.

[0183] In some implementations, the initial information may be information for PSCCH and / or PSSCH transmission provided by a higher layer of the first terminal device to a physical layer at the moment of resource selection triggering.

[0184] It can be seen that the first terminal device obtains the initial information based on S101, which provides a reliable data basis for the subsequent SL-U to select reasonable resources. S101 may be, for example, an operation performed by the physical layer of the first terminal device.

[0185] S102: Determine a candidate resource set based on the initial information.

[0186] The candidate resource set can be understood as an initial candidate resource set determined in a resource pool or a resource selection window, which is used for subsequent resource exclusion and determination of a final available resource set. In the embodiment of the present application, the following three possible ways of determining a candidate resource set are provided.

[0187] In a first possible implementation, the candidate resource set determined by S102 may also be expressed as a set of candidate single-slot resources. S102 may, for example, include: determining the candidate resource set based on at least one of the initial information, the target time, and the target frequency domain, the resources in the candidate resource set being located in one of the time units in the time domain, and the resources in the candidate resource set being located in a first number of RBsets in the frequency domain, wherein each RBset includes a second number of subchannels.

[0188] Among them, the resources in the candidate resource set need to meet at least one of the following conditions: Condition 31, the product of the first number and the second number is equal to the number of subchannels occupied by PSCCH / PSSCH transmission; Condition 32, the second number of subchannels are continuous subchannels; Condition 33, the indexes of the second number of subchannels occupied in different RBsets in the first number of RBsets are the same; Condition 34, the first number of RBsets are continuous RBsets; Condition 35, the first number of RBsets does not contain any unavailable RBsets in the initial information; Condition 36, the first number of RBsets does not contain any RBset with continuous LBT failures in the initial information; Condition 37, the first number is equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information; Condition 38, the first number of RBsets are RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information; Condition 39, the first number of RBsets are all or part of the RBsets in the available RBsets in the initial information.

[0189] It can be understood that the candidate resources in the candidate resource set can be understood as: located in one time unit in the time domain, located in N RBsets in the frequency domain, each RBset includes M subchannels, and determining the candidate resources is equivalent to the process of determining N and M. N and M correspond to the first quantity and the second quantity in the above description respectively.

[0190] As an example, assume that the transmission of the first terminal device needs to occupy 2 subchannels and is located in 2 consecutive RBsets, that is, the transmission of the first terminal device needs to occupy 2 consecutive RBsets, occupying 1 subchannel in each RBset, and the indexes of the two occupied subchannels need to be the same, for example, subchannel 1 and subchannel 2 are occupied in the first RBset, and subchannel 1 and subchannel 2 are also occupied in the second RBset. Figure 5As shown, if RBset#2 is an unavailable RBset (such as RBset#2 is an RBset that detects continuous LBT failures), the candidate single-slot resource is defined as occupying 2 consecutive RBsets, each RBset occupies 1 subchannel, and the indexes of these 2 subchannels are the same. In addition, the candidate single-slot resource cannot overlap with the unavailable RBset. Therefore, for time slot 0, (RBset#0-subchannel 0)+(RBset#1-subchannel 0) is a candidate single-slot resource, and (RBset#1-subchannel 0)+(RBset#2-subchannel 0) cannot be used as a candidate single-slot resource because the resource overlaps with the unavailable RBset#2. It can be seen that Figure 5 In the situation shown, there are 5 candidate single time slot resources for each time slot (respectively (RBset#0-subchannel 0) + (RBset#1-subchannel 0), (RBset#0-subchannel 1) + (RBset#1-subchannel 1), (RBset#0-subchannel 2) + (RBset#1-subchannel 2), (RBset#0-subchannel 3) + (RBset#1-subchannel 3), and (RBset#0-subchannel 4) + (RBset#1-subchannel 4)), and the total number of candidate single time slot resources included in the 5 time slots included in the resource selection window is 25.

[0191] It should be noted that in the drawings shown in the embodiments of the present application, the sub-channel is only a schematic diagram and does not represent the actual structure of the sub-channel. The actual sub-channel can be a continuous PRB structure or an IRB structure.

[0192] In a second possible implementation, S102 may, for example, include: determining the candidate resource set based on at least one of the initial information, the target time and the target frequency domain, the resources in the candidate resource set belonging to the target time in the time domain, and the resources in the candidate resource set belonging to the target frequency domain in the frequency domain.

[0193] Among them, the target frequency domain satisfies at least one of the following conditions: Condition 41, the target frequency domain is the RBset occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information (that is, the high layer of the first terminal device specifies a specific RBset as the frequency domain of the resource selection window); Condition 42, the target frequency domain is a third number of continuous RBsets in the resource pool, and the third number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission; Condition 43, the target frequency domain is a set of all target type RBsets in the resource pool, and the target type RBset set contains a fourth number of continuous RBsets, and the fourth number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission. The resources in the target frequency domain do not include RBsets in any of the following situations: Situation 1, RBsets with continuous LBT failures in the initial information; Situation 2, the fifth number of continuous RBsets, the fifth number being less than the number of RBsets occupied by PSCCH and / or PSSCH transmissions; Situation 3, independent RBsets, the independent RBsets do not constitute a continuous RBset with any other RBset in the resource pool. In Situation 1, the time domain restriction condition may be: all time within the resource selection window, or the time determined according to (4) in the initial information. In Situation 2, the fifth number of continuous RBsets do not include unavailable RBsets and / or RBsets with continuous LBT failures in the initial information, and the fifth number of continuous RBsets do not constitute a continuous RBset with other RBsets in the resource pool. In Situation 3, the number of RBsets required for actual transmission is required to be greater than 1.

[0194] Alternatively, the target frequency domain may also be all frequency domains of the resource pool or all sub-channels in the resource pool.

[0195] As an example, the upper layer of the first terminal device specifies the RBset. It is understandable that the first terminal device takes all candidate single-slot resources of the RBset in the resource pool indicated in the time period [n+T1, n+T2] as candidate resources, and the number is recorded as Mtotal. Here, [n+T1, n+T2] refers to the target time. Figure 5 As shown, the high-level layer indicates that the RBsets for PSCCH and / or PSSCH transmission are located in RBset#0 and RBset#1, and the candidate resource sets are only all candidate single-slot resource sets in RBset#0 and RBset#1. Assuming that the transmission of the first terminal device needs to occupy 2 subchannels, and the subchannel indexes located in different RBsets need to be the same, then Mtotal is equal to 25.

[0196] As another example, the high layer of the first terminal device indicates the number of continuous RBsets, the number of subchannels occupied, or the number of subchannels occupied in each RBset for PSCCH and / or PSSCH transmission. It is understandable that the first terminal device takes all candidate single-slot resources within the range of the number of RBsets occupied by PSCCH and / or PSSCH transmissions within the time period [n+T1, n+T2] as candidate resources. Figure 6 As shown, the resource pool contains a total of 5 RBsets, each RBset has 5 subchannels, RBset#3 is an RBset that detects continuous LBT failures, that is, an unavailable RBset; the transmission of PSCCH and / or PSSCH occupies 2 RBsets, and the number of subchannels occupied is 2; and the subchannel indexes occupied by different RBsets are the same. Therefore, candidate single-slot resources can only be defined in RBset#0 and RBset#1, and RBset#1 and RBset#2. There are a total of 5 candidate single-slot resources in RBset#0 and RBset#1, and a total of 5 candidate single-slot resources in RBset#1 and RBset#2. In this way, Mtotal is equal to 10. In this example, candidate single-slot resources cannot be defined in a separate RBset#4, nor can candidate single-slot resources be defined in RBset#3+RBset#4. In addition, the physical layer of the first terminal device can determine RBset#0, RBset#1 and RBset#2 as available RBsets, and report the available resource set determined after resource exclusion to the higher layer. In addition to the available resource set, the physical layer also needs to report the RBset that determines the available resource set, i.e., RBset#0, RBset#1 and RBset#2.

[0197] In a third possible implementation, S102 may include, for example: based on the initial information, grouping all resources in the resource selection window into the candidate resource set. In this implementation, reference may be made to the process of determining the set of all candidate single-slot resources in the resource selection process of New Radio Vehicle to Everything Mode 2 (NR-V2X Mode 2). The process of determining the set of all candidate single-slot resources in the resource selection process of NR-V2X Mode 2 may include: S11, the candidate single-slot resource Rx, y is t within the time [n+T1, n+T2]. y Continuous L on the slot subCH sub-channels, where 0≤T1≤T proc,1 , T proc,1represents the transmission processing delay of the first terminal device, which can be {3, 5, 9, 17} physical time slots, corresponding to sub-carrier space (SCS) of {15, 30, 60, 120} kHz, respectively. 2min ≤T2≤remainingPDB,T 2min The minimum value of T2 configured by the high-level parameter t2min_SelectionWindow, remainingPDB is the remaining packet delay budget (i.e., remainingpacketdelaybudget), and the total number of candidate single-slot resources in the resource selection window is Mtotal. S12, the first terminal device continuously monitors the perception window [n-T0, nT proc,0 ) slot, performs PSCCH, PSSCH decoding and PSSCH-reference signal received power (RSRP) or PSCCH-RSRP measurement, T0 is the perception window length configured by the high layer, T proc,0 The time for the first terminal device to process the previous perception result can be {1, 1, 2, 4} slots, corresponding to SCS {15, 30, 60, 120} kHz. S13, Th(pi, pj) indicates the i-th RSRP field in sl-ThresPSSCH-RSRP-List-r16, i=pi+(pj-1)*8, pi indicates the priority indicated in the received direct link control information (SidelinkControlInformation, SCI), pj indicates the priority of the first terminal device to send the transmission, pj=prio TX S14, initialize S A is the set of all candidate single-slot resources.

[0198] It can be seen that the first terminal device determines the candidate resource set according to S102, and is ready for subsequent resource exclusion and resource selection. S102 may be, for example, an operation performed by the physical layer of the first terminal device.

[0199] S103: Eliminate resources from the candidate resource set to obtain an available resource set.

[0200] In specific implementation, after obtaining the candidate resource set, the first terminal device can flexibly determine the exclusion strategy to be adopted for resource exclusion based on demand. The excluded resource types may include at least one of the following: target class candidate resources, candidate resources determined according to SCI decoding information and RSRP measurement values, and candidate resources determined according to unmonitored time slots and cycles. Here, only the types of excluded candidate resources are explained, and the order of resource exclusion is not emphasized. For example, the order of resource exclusion operations may be: first exclude target class candidate resources, then exclude candidate resources determined according to unmonitored time slots and cycles, and finally exclude candidate resources determined according to SCI decoding information and RSRP measurement values; the order of resource exclusion operations may also be: first exclude candidate resources determined according to unmonitored time slots and cycles, then exclude target class candidate resources, and finally exclude candidate resources determined according to SCI decoding information and RSRP measurement values. Among them, the target class candidate resources are located in the target RBset, which may refer to the target class candidate resources and the target RBset having an intersection (also referred to as overlap), including partial overlap or full overlap of the target class candidate resources and the target RBset.

[0201] The target RBset satisfies at least one of the following conditions: Condition 51, the target RBset is the RBset with consecutive LBT failures in the initial information; Condition 52, the target RBset is the unavailable RBset in the initial information; Condition 53, the target RBset is the sixth number of consecutive RBsets, and the sixth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission; Condition 54, the target RBset is an independent RBset, and the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool. Condition 54 requires that the number of RBsets required for actual transmission is greater than 1.

[0202] It can be understood that after the resource exclusion in S103, it is required that the ratio of the number of resources in the available resource set to the number of resources in the first resource set is greater than or equal to the first threshold (such as 20%). The available resource set can also be represented as a remaining candidate resource set or a remaining candidate resource set that meets the requirements, and the first resource set is any of the following: the first resource set is all candidate resources in the resource selection window; the first resource set is all candidate resources in the resource selection window except the target class candidate resources; the first resource set is all candidate resources in the target frequency domain; the first resource set is all candidate resources in the target frequency domain except the target class candidate resources.

[0203] For example, the first resource set includes 10 resources, and the number of resources included in the available resource set must be greater than or equal to (20%*10)=2.

[0204] It should be noted that if after resource exclusion, the number of resources in the available resource set (or the remaining candidate resource set) does not meet the requirements, it is necessary to increase the RSRP threshold value and then re-execute resource exclusion or re-execute partial resource exclusion.

[0205] It can be seen that the first terminal device determines the available resource set according to S103, and is ready for subsequent resource selection. S103 may be, for example, an operation performed by the physical layer of the first terminal device.

[0206] As an example, after S103, it may also include: the physical layer of the first terminal device sends the available resource set and the RBset where the available resource set is located to the upper layer, so that the upper layer performs the following S104 selection operation accordingly.

[0207] Optionally, after S103, the method may further include:

[0208] S104: Select a target resource from the set of available resources, where the target resource is used by the first terminal device to perform a direct link communication with the second terminal device operating in an unlicensed frequency band.

[0209] In specific implementation, after obtaining the available resource set, the first terminal device can flexibly determine the selection strategy to be adopted for resource selection based on demand. The embodiments of the present application do not limit the specific selection strategy.

[0210] Optionally, after S104, the method may further include:

[0211] S105: The first terminal device and the second terminal device perform SL-U communication based on the target resource.

[0212] In this way, in this method, after the first terminal device obtains the initial information of the other party corresponding to the Sidelink, it successively obtains the available resource set through the steps of determining the candidate resource set and resource exclusion. Thus, the first terminal device can select a suitable target resource according to the available resource set and the RBset where the available resource set is located, and prepares for the first terminal device to perform SL-U communication with the other party through the target resource.

[0213] In some implementations, considering that in a congestion control mechanism, sending parameters are usually determined based on CBR, the definition of RSSI provided in the embodiment of the present application makes CBR more accurate. Based on the accurate CBR, more appropriate sending parameters can be matched in the congestion control mechanism, thereby improving the transmission performance of the service.

[0214] As an example, the method may also include: matching corresponding sending parameters based on the CBR; and sending the service to be sent to the second terminal device along the SL-U based on the target resources and the sending parameters.

[0215] Among them, the sending parameters may include a first parameter set and a second parameter set, the first parameter set including at least one of the following parameters: maximum transmission power, number of retransmissions, number of sub-channels occupied by resources, and modulation and coding scheme (Modulation and Coding Scheme, MCS) range; the second parameter set includes a channel occupancy (Channel Occupancy Ratio, CR) upper limit, if the measured channel occupancy exceeds the channel occupancy upper limit, the sending of the service to be sent is abandoned.

[0216] In addition, in order to further optimize the first possible implementation in S102 above, the method may further include: obtaining a CBR, where the CBR is the ratio of the number of subchannels whose RSSI exceeds the second threshold to the number of all subchannels in the target measurement window. Optionally, parameters such as the number of subchannels occupied by PSCCH and / or PSSCH transmissions and the maximum transmission power can be determined based on the measurement result of the CBR. In this way, the reliability of transmission can be guaranteed, thereby improving the reliability of the system. The embodiments of the present application define several methods for calculating RSSI, see the description of the relevant parts below.

[0217] Among them, the frequency domain range of the target measurement window is at least one of the following: the frequency domain range of the resource pool and / or resource selection window; the RBset in the resource pool and / or resource selection window except the unavailable RBset in the initial information; the RBset in the resource pool and / or resource selection window except the RBset with continuous LBT failure in the initial information, the target frequency domain; the RBset in the target frequency domain except the unavailable RBset in the initial information; the RBset in the target frequency domain except the RBset with continuous LBT failure in the initial information.

[0218] The process of measuring CBR can also be described as: determining the ratio of the subchannel that meets the second condition within the target measurement period to all subchannels in the target measurement window as CBR, wherein the above second condition can be: the first RSSI corresponding to the subchannel exceeds a preset threshold value.

[0219] In order to make the obtained CBR more accurate, a more reasonable RSSI calculation method is designed. Each time slot includes multiple symbols, including one or two candidate start symbols for PSCCH and / or PSCCH transmission. RSSI is defined as at least one of the following: the linear average value of all received powers on the orthogonal frequency division multiplexing OFDM symbols configured for PSCCH and PSSCH in a time slot except the start symbol; the maximum value of at least two values ​​among the first value, the second value, and the third value. Among them, the first value is the linear average value of the received power on all symbols between the first start symbol and the second start symbol (excluding the first start symbol and the second start symbol) in the OFDM symbols configured for PSCCH and PSSCH in a time slot, the second value is the linear average value of the received power on all symbols after the second start symbol (excluding the second start symbol) in the OFDM symbols configured for PSCCH and PSSCH in a time slot; the third value is the linear average value of the received power on all symbols in the OFDM symbols configured for PSCCH and PSSCH in a time slot except the first start symbol and the second start symbol. The first starting symbol here represents the first candidate starting symbol of PSCCH and / or PSCCH transmission in a time slot, and the second starting symbol represents the second candidate starting symbol of PSCCH and / or PSCCH transmission in a time slot, such as Figure 7 As shown, a time slot includes 14 symbols, of which 13 symbols are symbols configured for PSCCH and PSSCH transmission (symbol 0-symbol 12), and the last symbol is used for transceiver conversion. Assuming that the energy measured on each symbol is P0-P13 respectively, then, in one case, RSSI is defined as: RSSI = (P1+P2+…+P5+P7+…+P12) / 11; in another case, RSSI = Max{RSSI-1, RSSI-2}, or RSSI = Max{RSSI-1, RSSI-2, RSSI-3}, or RSSI = Max{RSSI-1, RSSI-3}, where RSSI-1 = (P1+P2+…+P5+P7+…P12) / 11, RSSI-2 = (P1+P2+…+P5) / 5, RSSI-3 = (P7+P8+…+P12) / 6.

[0220] In an embodiment of the present application, a process of measuring the channel occupancy ratio (Channel Occupancy Ratio, CR) may also be included. CR represents the ratio of the subchannels occupied in the measurement window and / or the subchannels authorized to be occupied (expected to be occupied) to all subchannels in the measurement window. The frequency domain range of the measurement window for measuring CR is at least one of the following: the frequency domain range of the resource pool / resource selection window; the RBsets in the resource pool / resource selection window except the unavailable RBsets in the initial information; the RBsets in the resource pool / resource selection window except the RBsets with continuous LBT failures in the initial information, the target frequency domain; the RBsets in the target frequency domain except the unavailable RBsets in the initial information; the RBsets in the target frequency domain except the RBsets with continuous LBT failures in the initial information. For example, the resource pool includes 3 RBsets: RBset#0, RBset#1 and RBset#2, where RBset#0 is the RBset in which continuous LBT failures are detected, and the frequency domain range when measuring CR is only RBset#1 and RB set#2.

[0221] It can be seen that through the definition of RSSI and the method of measuring CBR provided in the embodiment of the present application, a more accurate CBR can be obtained, making it possible to determine reasonable sending parameters during the congestion control process.

[0222] It should be noted that the definition of RSSI, the measurement of CR, and the measurement of CBR may be performed before S102 or after S102.

[0223] It should be noted that the definition of RSSI, the method of measuring CR, the method of measuring CBR, and the process of determining the transmission parameters provided in the embodiments of the present application can be implemented as an embodiment alone or in combination with the embodiment of the present application. Figure 2 The method shown is protected together.

[0224] In this way, the SL-U resource determination mechanism provided in the embodiment of the present application can, on the one hand, reduce the complexity of the overall resource selection process and reduce the overhead of resource indication, and can also reduce the impact of failure to transmit due to channel access failure, thereby increasing the efficiency of transmission. On the other hand, an RSSI measurement method suitable for the special structure of SL-U is also provided to ensure that the RSSI measurement is more accurate, thereby also improving the accuracy of measuring CBR.

[0225] It should be noted that the above embodiments are all based on the first terminal device as the execution subject, and introduce how to implement the selection of SL-U resources when the first terminal device needs to communicate with the second terminal device using SL-U. When other terminal devices need to communicate with other terminal devices using SL-U, they can also execute this method. For details, see Figure 2 In the embodiment shown, for example, when the second terminal device has a need to communicate with the first terminal device using SL-U, the second terminal device can also serve as the executor of the method, selecting resources to be used for SL-U communication with the first terminal device, and specifically replacing the first terminal device with the second terminal device in each step of the above method as a specific embodiment of the method executed by the second terminal device.

[0226] Accordingly, the embodiment of the present application further provides a direct link resource selection device 800 operating in an unlicensed frequency band, such as Figure 8 The apparatus 800 is applied to a first terminal device and includes:

[0227] An acquisition unit 801 is used to acquire initial information;

[0228] A determining unit 802, configured to determine a candidate resource set based on the initial information;

[0229] The obtaining unit 803 is used to exclude resources from the candidate resource set to obtain an available resource set.

[0230] Optionally, the selection unit 804 is configured to select a target resource from the set of available resources.

[0231] Optionally, the initial information includes at least one of the following information:

[0232] Available RBsets;

[0233] Unavailable RBset;

[0234] RBset with consecutive LBT failures;

[0235] Time information corresponding to RBsets with consecutive LBT failures;

[0236] The number of RBsets occupied by PSCCH and / or PSSCH transmissions in one time unit;

[0237] RBsets occupied by PSCCH and / or PSSCH transmissions within a time unit;

[0238] The number of subchannels occupied by PSCCH and / or PSSCH transmissions in one time unit;

[0239] The number of subchannels occupied by PSCCH and / or PSSCH transmission in one RBset in one time unit;

[0240] The starting PRB of the resource pool.

[0241] Optionally, the available RBset satisfies at least one of the following conditions:

[0242] The available RBset is a continuous RBset in the frequency domain;

[0243] The available RBset does not include a RBset with consecutive LBT failures;

[0244] The number of RBsets in any combination of consecutive RBsets in the available RBsets is greater than or equal to the number of RBsets occupied by PSSCH and / or PSCCH transmission.

[0245] Optionally, the RBset occupied by PSCCH and / or PSSCH transmission within the one time unit satisfies at least one of the following conditions:

[0246] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit are continuous RBsets in the frequency domain;

[0247] The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit do not include RBsets with continuous LBT failures.

[0248] Optionally, the resources in the candidate resource set need to meet at least one of the following conditions:

[0249] Located in one of the time units in the time domain;

[0250] The frequency domain includes a first number of RBsets, wherein each RBset occupies a second number of subchannels.

[0251] Optionally, the first quantity and / or the second quantity needs to satisfy at least one of the following conditions:

[0252] The product of the first number and the second number is equal to the number of subchannels occupied by PSCCH / PSSCH transmission;

[0253] The second number of sub-channels are continuous sub-channels;

[0254] Indexes of the second number of sub-channels occupied by different RBsets in the first number of RBsets are the same;

[0255] The first number of RBsets are continuous RBsets;

[0256] The first number of RBsets does not include any unavailable RBset in the initial information;

[0257] The first number of RBsets does not include any RBset with continuous LBT failure in the initial information;

[0258] The first number is equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission in a time unit in the initial information;

[0259] The first number of RBsets are RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information.

[0260] Optionally, the determining unit 802 is specifically configured to:

[0261] Based on at least one of the initial information, the target time and the target frequency domain, the candidate resource set is determined, the resources in the candidate resource set belong to the target time in the time domain, and the resources in the candidate resource set belong to the target frequency domain in the frequency domain.

[0262] Optionally, the target frequency domain satisfies at least one of the following conditions:

[0263] The target frequency domain is an RBset occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information;

[0264] The target frequency domain is a third number of continuous RBsets in the resource pool, and the third number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0265] The target frequency domain is a set of all target type RBsets in the resource pool, and the target type RBset set includes a fourth number of continuous RBsets, and the fourth number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0266] Optionally, the target frequency domain resources do not include an RB set in at least one of the following situations:

[0267] RBsets with consecutive LBT failures in the initial information;

[0268] A fifth number of consecutive RBsets, where the fifth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission.

[0269] An independent RBset, where the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0270] Optionally, the obtaining unit 803 is specifically configured to:

[0271] From the candidate resource set, target class candidate resources are excluded to obtain the available resource set, and the target class candidate resources are located in the target RBset.

[0272] Optionally, the target RBset satisfies at least one of the following conditions:

[0273] The target RBset is the RBset with consecutive LBT failures in the initial information;

[0274] The target RBset is an unavailable RBset in the initial information;

[0275] The target RBset is a sixth number of consecutive RBsets, where the sixth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission;

[0276] The target RBset is an independent RBset, and the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

[0277] Optionally, a ratio of the number of resources in the available resource set to the number of resources in the first resource set is greater than or equal to a first threshold,

[0278] The first resource set is any one of the following:

[0279] The first resource set is all candidate resources in the resource selection window;

[0280] The first resource set is all candidate resources in the resource selection window except the target class candidate resources.

[0281] Optionally, the device 800 further includes:

[0282] The calculation unit is used to obtain a CBR, where the CBR is the ratio of the number of sub-channels whose RSSI exceeds the second threshold to the number of all sub-channels in the resource selection window.

[0283] Optionally, the RSSI is defined in any one of the following ways:

[0284] The RSSI is the linear average of all received powers on orthogonal frequency division multiplexing OFDM symbols except the start symbol configured for PSCCH and PSSCH in a time slot;

[0285] The RSSI is the maximum value of at least two values ​​among a first value, a second value, and a third value, wherein the first value is the linear average value of the received power on all symbols between the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; the second value is the linear average value of the received power on all symbols after the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; and the third value is the linear average value of the received power on all symbols except the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot.

[0286] Optionally, the frequency domain range of the target measurement window is at least one of the following:

[0287] The frequency domain scope of the resource pool;

[0288] RBsets in the resource pool except the unavailable RBset in the initial information;

[0289] RBsets in the resource pool except the RBset with consecutive LBT failures in the initial information.

[0290] It should be noted that the specific implementation method of the device 800 and the technical effects achieved can be found in Figure 2 The relevant description in the method shown.

[0291] In addition, the present application embodiment also provides a terminal device 900, such as Fig. 9 As shown, the terminal device 900 includes a processor 901 and a memory 902:

[0292] The memory 902 is used to store programs;

[0293] The processor 901 is used to execute according to the program Figure 2 The method provided.

[0294] In addition, an embodiment of the present application further provides a storage medium, which is used to store a program, and the program runs on a processor to execute the method provided by the embodiment of the present application.

[0295] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. In addition, the "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated with each other are in an "or" relationship.

[0296] Through the description of the above implementation methods, it can be known that those skilled in the art can clearly understand that all or part of the steps in the above-mentioned embodiment method can be implemented by means of software plus a general hardware platform. Based on such an understanding, the technical solution of the present application can be embodied in the form of a software product, which can be stored in a storage medium, such as a read-only memory (ROM) / RAM, a magnetic disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network communication device such as a router) to execute the methods described in each embodiment of the present application or some parts of the embodiments.

[0297] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for system embodiments and device embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and system embodiments described above are merely schematic, in which the modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0298] The above is only a preferred embodiment of the present application and is not intended to limit the protection scope of the present application. It should be noted that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the present application, and these improvements and modifications should also be regarded as the protection scope of the present application.

Claims

1. A method for determining direct link resources working in an unlicensed frequency band, characterized in that: Applied to the first terminal device, including: Get initial information; Based on the initial information, determining a set of candidate resources; The candidate resource set is excluded to obtain an available resource set.

2. The method according to claim 1, characterized in that: The initial information includes at least one of the following information: Available resource block set RBset; Unavailable RBset; RBsets with consecutive listen-before-speak LBT failures; Time information corresponding to RBsets with consecutive LBT failures; The number of RBsets occupied by the transmission of the physical direct link control channel PSCCH and / or the physical direct link shared channel PSSCH in one time unit; RBsets occupied by PSCCH and / or PSSCH transmissions within a time unit; The number of subchannels occupied by PSCCH and / or PSSCH transmissions in one time unit; The number of subchannels occupied by PSCCH and / or PSSCH transmission in one RBset in one time unit; The starting physical resource block PRB of the resource pool.

3. The method according to claim 2, characterized in that The available RBset satisfies at least one of the following conditions: The available RBset is a continuous RBset in the frequency domain; The available RBset does not include a RBset with consecutive LBT failures; The number of RBsets in any continuous RBset combination among the available RBsets is greater than or equal to the number of RBsets occupied by PSSCH and / or PSCCH transmission.

4. The method according to claim 2, characterized in that: The RBsets occupied by PSCCH and / or PSSCH transmission within the time unit meet at least one of the following conditions: The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit are continuous RBsets in the frequency domain; The RBsets occupied by PSCCH and / or PSSCH transmission within the one time unit do not include RBsets with continuous LBT failures.

5. The method according to any one of claims 1 to 4, characterized in that: The resources in the candidate resource set need to meet at least one of the following conditions: Located in one of the time units in the time domain; In the frequency domain, a first number of RBsets are located, wherein a second number of subchannels are occupied in each RBset.

6. The method according to claim 5, characterized in that The first quantity and / or the second quantity needs to satisfy at least one of the following conditions: The product of the first number and the second number is equal to the number of subchannels occupied by PSCCH and / or PSSCH transmission; The second number of sub-channels are continuous sub-channels; Indexes of the second number of sub-channels occupied by different RBsets in the first number of RBsets are the same; The first number of RBsets are continuous RBsets; The first number of RBsets does not include any unavailable RBset in the initial information; The first number of RBsets does not include any RBset with continuous LBT failure in the initial information; The first number is equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission in a time unit in the initial information; The first number of RBsets are RBsets occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information.

7. The method according to any one of claims 1 to 4, characterized in that: The step of determining a candidate resource set based on the initial information includes: Based on at least one of the initial information, the target time and the target frequency domain, the candidate resource set is determined, the resources in the candidate resource set belong to the target time in the time domain, and the resources in the candidate resource set belong to the target frequency domain in the frequency domain.

8. The method according to claim 7, characterized in that The target frequency domain satisfies at least one of the following conditions: The target frequency domain is an RBset occupied by PSCCH and / or PSSCH transmission within a time unit in the initial information; The target frequency domain is a third number of continuous RBsets in the resource pool, where the third number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission; The target frequency domain is a set of all target type RBsets in the resource pool, and the target type RBset set includes a fourth number of continuous RBsets, and the fourth number is greater than or equal to the number of RBsets occupied by PSCCH and / or PSSCH transmission.

9. The method according to claim 7 or 8, characterized in that: The target frequency domain resources do not include RBsets in at least one of the following situations: RBsets with consecutive LBT failures in the initial information; a fifth number of consecutive RBsets, wherein the fifth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission; An independent RBset, where the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

10. The method according to any one of claims 1 to 4, characterized in that: The step of excluding resources from the candidate resource set to obtain an available resource set includes: From the candidate resource set, target class candidate resources are excluded to obtain the available resource set, and the target class candidate resources are located in the target RBset.

11. The method according to claim 10, characterized in that The target RBset satisfies at least one of the following conditions: The target RBset is the RBset with consecutive LBT failures in the initial information; The target RBset is an unavailable RBset in the initial information; The target RBset is a sixth number of consecutive RBsets, where the sixth number is less than the number of RBsets occupied by PSCCH and / or PSSCH transmission; The target RBset is an independent RBset, and the independent RBset does not constitute a continuous RBset with any other RBset in the resource pool.

12. The method according to any one of claims 1 to 11, characterized in that: The ratio of the number of resources in the available resource set to the number of resources in the first resource set is greater than or equal to a first threshold, wherein the first resource set is any one of the following: The first resource set is all candidate resources in the resource selection window; The first resource set is all candidate resources in the resource selection window except the target class candidate resources.

13. The method according to any one of claims 1 to 12, characterized in that: The method further comprises: A channel busy rate CBR is obtained, where the CBR is the ratio of the number of sub-channels whose received signal strength indication RSSI exceeds the second threshold to the number of all sub-channels in the target measurement window.

14. The method according to claim 13, characterized in that The RSSI is defined in any of the following ways: The RSSI is the linear average of all received powers on orthogonal frequency division multiplexing OFDM symbols except the start symbol configured for PSCCH and PSSCH in a time slot; The RSSI is the maximum value of at least two values ​​among a first value, a second value, and a third value, wherein the first value is the linear average value of the received power on all symbols between the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot, and the second value is the linear average value of the received power on all symbols after the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot; the third value is the linear average value of the received power on all symbols except the first starting symbol and the second starting symbol in the OFDM symbols configured for PSCCH and PSSCH in a time slot.

15. The method according to claim 13 or 14, characterized in that The frequency domain range of the target measurement window is at least one of the following: The frequency domain scope of the resource pool; RBsets in the resource pool except the unavailable RBset in the initial information; RBsets in the resource pool except the RBset with consecutive LBT failures in the initial information.

16. A device for determining direct link resources operating in an unlicensed frequency band, characterized in that: Applied to the first terminal device, including: An acquisition unit, used for acquiring initial information; A determination unit, configured to determine a candidate resource set based on the initial information; The obtaining unit is used to exclude resources from the candidate resource set to obtain an available resource set.

17. A terminal device, characterized in that: The terminal device includes a processor and a memory: The memory is used to store programs; The processor is configured to execute the method according to any one of claims 1 to 15 according to the program.

18. A storage medium, characterized in that: The storage medium is used to store a program, and the program runs on a processor to execute the method according to any one of claims 1 to 15.

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