WO2023050376A1

WO2023050376A1 - Methods and devices for candidate resource set initialization and user equipment

Info

Publication number: WO2023050376A1
Application number: PCT/CN2021/122356
Authority: WO
Inventors: Huei-Ming Lin; Zhenshan Zhao; Shichang Zhang; Yi Ding; Teng MA
Original assignee: Guangdong Oppo Mobile Telecommunications Corp., Ltd.
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2023-04-06

Abstract

Methods and devices for candidate resource set initialization and user equipment (UE) are provided. The method is performed by a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and includes: initializing a candidate resource set according to SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE).

Description

METHODS AND DEVICES FOR CANDIDATE RESOURCE SET INITIALIZATION AND USER EQUIPMENT

TECHNICAL FIELD

The application generally relates to sidelink (SL) communication technology and in particular, relates to methods and devices for candidate resource set initialization and user equipment (UE) .

BACKGROUND

Internet of vehicles (IoV) (also referred to as vehicle to everything (V2X) ) communication adopts a device to device (D2D) -based sidelink (SL) transmission technology. Different from a traditional long term evolution (LTE) system in which data are received or sent via a base station, an IoV system adopts a direct terminal-to-terminal communication, and therefore has a higher spectrum efficiency and lower transmission delay.

In 5 ^th generation (5G) (that is, new radio (NR) ) V2X (NR-V2X) communication, a terminaldevice can use a specific transmission mode for data transmission. For example, in SL transmission Mode 1, the terminal device can transmit data on a transmission resource configured by a network device. In SL transmission Mode 2, the terminal device can transmit data on a transmission resource selected autonomously on its own. In SL transmission Mode 2, how to avoid resource collision between UEs has attracted extensive attention.

SUMMARY

Disclosed herein are implementations of methods and devices for candidate resource set initialization and UEs.

In a first aspect, a method for candidate resource set initialization is provided. The method is performed by a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and includes: initializing a candidate resource set according to SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE) .

In one implementation of the first aspect, initializing the candidate resource set according to the SL-DRX active time includes: initializing the candidate resource set in such a manner that the candidate resource set overlaps at least N slots of the SL-DRX active time of the Rx-UE, where N is an integer and N ≥ 1.

In one implementation of the first aspect, the method further includes: initializing the candidate resource set according to a monitoring window for partial sensing.

In one implementation of the first aspect, initializing the candidate resource set according to a monitoring window for partial sensing includes: initializing the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In one implementation of the first aspect, the method includes: initializing the candidate resource set according to a set of Y candidate slots, where Y is an integer and Y ≥ 1.

In one implementation of the first aspect, initializing the candidate resource set according to the set of Y candidate slots includes: initializing the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots.

In one implementation of the first aspect, initializing the candidate resource set according to the set of Y candidate slots includes: initializing the candidate resource set in such a manner that the candidate resource set is equal to all candidate single-slot resources in the set of Y candidate slots.

In a second aspect, a method for candidate resource set initialization is provided. The method is performed by a Tx-UE in an SL mode 2 resource selection or reselection procedure and includes: initializing a candidate resource set according to a monitoring window for partial sensing.

In one implementation of the second aspect, initializing the candidate resource set according to the monitoring window for partial sensing includes: initializing the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In a third aspect, a method for candidate resource set initialization is provided. The method is performed by a Tx-UE in an SL mode 2 resource selection or reselection procedure and includes: initializing a candidate resource set according to a set of Y candidate slots, where Y is an integer and Y ≥ 1.

In one implementation of the third aspect, initializing the candidate resource set according to the set of Y candidate slots includes: initializing the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots that are located within a resource selection window.

In a fourth aspect, a device for candidate resource set initialization is provided. The device is used for a Tx-UE in an SL mode 2 resource selection or reselection procedure and includes: a processing unit, configured to initialize a candidate resource set according to SL-DRX active time of a Rx-UE.

In one implementation of the fourth aspect, the processing unit configured to initialize the candidate resource set according to the SL-DRX active time is configured to: initialize the candidate resource set in such a manner that the candidate resource set overlaps at least N slots of the SL-DRX active time of the Rx-UE, where N is an integer and N ≥ 1.

In one implementation of the fourth aspect, the processing unit is further configured: initialize the candidate resource set according to a monitoring window for partial sensing.

In one implementation of the fourth aspect, the processing unit configured to initialize the candidate resource set according to a monitoring window for partial sensing is configured to: initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In one implementation of the fourth aspect, the processing unit is further configured: initialize the candidate resource set according to a set of Y candidate slots, where Y is an integer and Y≥1.

In one implementation of the fourth aspect, the processing unit configured to initialize the candidate resource set according to the set of Y candidate slots is configured to: initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots.

In one implementation of the fourth aspect, the processing unit configured to initialize the candidate resource set according to the set of Y candidate slots is configured to: initialize the candidate resource set in such a manner that the candidate resource set is equal to all candidate single-slot resources in the set of Y candidate slots.

In a fifth aspect, a device for candidate resource set initialization is provided. The device is used for a Tx-UE in an SL mode 2 resource selection or reselection procedure and includes: a processing unit, configured to initialize a candidate resource set according to a monitoring window for partial sensing.

In one implementation of the fifth aspect, the processing unit configured to initialize the candidate resource set according to the monitoring window for partial sensing is configured to: initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In a sixth aspect, a device for candidate resource set initialization is provided. The device is used for a Tx-UE in an SL mode 2 resource selection or reselection procedure and includes: a processing unit, configured to initialize a candidate resource set according to a set of Y candidate slots, where Y is an integer and Y ≥ 1.

In one implementation of the sixth aspect, the processor configured to initialize the candidate resource set according to the set of Y candidate slots is configured to: initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots that are located within a resource selection window.

In a seventh aspect, a UE is provided. The UE includes a processor and a memory. The memory is configured to store a computer program (s) . The processor is configured to invoke and run the computer program stored in the memory to perform the method of the first aspect and/or implementations thereof.

In an eighth aspect, a UE is provided. The UE includes a processor and a memory. The memory is configured to store a computer program (s) . The processor is configured to invoke and run the computer program stored in the memory to perform the method of the second aspect and/or implementations thereof.

In a ninth aspect, a UE is provided. The UE includes a processor and a memory. The memory is configured to store a computer program (s) . The processor is configured to invoke and run the computer program stored in the memory to perform the method of the third aspect and/or implementations thereof.

In a tenth aspect, a chip is provided. The chip includes a processor configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of the first aspect and/or implementations thereof.

In an eleventh aspect, a chip is provided. The chip includes a processor configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of the second aspect and/or implementations thereof.

In a twelfth aspect, a chip is provided. The chip includes a processor configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of the third aspect and/or implementations thereof.

In a thirteenth aspect, a computer-readable storage medium is provided. The computer-readable storage medium stores computer programs, whichare operable with a computer to performany of the method of the first aspect and/or implementations thereof, the second aspect and/or implementations thereof, or the third aspect and/or implementations thereof.

In a fourteenth aspect, a computer program product is provided. The computer program product includes computer program instructions, whichare operable with a computer to performany of the method of the first aspect and/or implementations thereof, the second aspect and/or implementations thereof, or the third aspect and/or implementations thereof.

In a fifteenth aspect, a computer program is provided. The computer programis operable with a computer to perform the method of the first aspect and/or implementations thereof, the second aspect and/or implementations thereof, or the third aspect and/or implementations thereof.

With aid of technical schemes provided herein, it is possible to ensure the transmitted SL data is within the receivable time duration of the target/destination Rx-UE and there is sufficient amount of channel sensing results to minimize transmission collision with other UEs. Therefore, retransmission of the same data packet is minimized when the candidate resource set for selection is confined within or overlaps with the receivable time region of the target/destination Rx-UE (Rx-UE’s SL-DRX active time) , transmission collision/interference to other UEs is minimized, and the SL communication reliability is maximized with a guaranteed minimum channel monitoring time length and corresponding sensing results.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to-scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

FIG. 1 is a schematic architectural diagram illustrating an application scenario according to implementations.

FIG. 2 is a schematic diagram illustrating resource set initialization in the relate art.

FIG. 3 is a further schematic diagram illustrating the resource set initialization of FIG. 1.

FIG. 4 is a further schematic diagram illustrating the resource set initialization of FIG. 1.

FIG. 5 is a schematic flowchart illustrating a method for candidate resource set initialization provided in implementations of the disclosure.

FIG. 6 is a schematic flowchart illustrating candidate resource set initialization for periodic transmission according to implementations of the disclosure.

FIG. 7 is an exemplary illustration of the proposed method for initializing a set of candidate resources (S _A) for periodic SL transmission when Rx-UE’s SL-DRX active time is provided.

FIGs. 8-10 are exemplary illustrations of the proposed method for initializing a set of candidate resources (S _A) for aperiodic SL transmission when Rx-UE’s SL-DRX active time is provided.

FIG. 11 is a schematic block diagram illustrating a device for candidate resource set initialization provided in implementations of the disclosure.

FIG. 12 is schematic block diagram illustrating a UE provided in implementations of the disclosure.

FIG. 13 is schematic block diagram illustrating a chip provided in implementations of the disclosure.

DETAILED DESCRIPTION

Terms used in this disclosure are given below for ease of explanation.

Partial sensing: Partial sensing is a method of checking available resources by decoding channel (s) such as physical sidelink (SL) control channel (PSCCH) for only a part of the entire data period. When partial sensing is used, the power consumption is reduced as much as the decoding time is reduced. Partial sensing can be classified into periodic-based partial sensing (PBPS) and contiguous partial sensing (CPS) .

PBPS: The transmitter user equipment (Tx-UE) can perform PBPS to detect periodic SL resource reservation from other user equipment (UEs) in a SL resource pool. In PBPS, a Tx-UE monitors periodically occurring sensing occasions that correspond to a set of Y candidate slots, which is selected by the Tx-UE within a resource selection window (RSW) .

CPS: The Tx-UE can perform CPS to detect dynamic SL resource reservation from other UEs in a SL resource pool. As can be seen, CPS differs from PBPS in terms of the type of resource reservation. Specifically, CPS is dynamic or aperiodic SL resource reservation related, while PBPS is periodic SL resource reservation related. In (CPS) , a Tx-UE monitors a set of consecutive slots within a Mode 2 resource pool in a CPS monitoring window.

RSW: In RSW, SL transmission resource and/or SL retransmission resource are selected.

Discontinuous reception (DRX) : DRX is a mechanism in which UE gets into a sleep mode for a certain period of time (also known as sleep time or OFF time) and wakes up for another period of time (also known as active time, ON time, etc. ) , where all data or data packets are transmitted/received during the active time. Specifically, in the sleep time, the UE does not listen to other UEs and therefore is unable to receive data, no matter whether there is any data arrived or not. In the active time, the UE wakes up to check if there is any data coming. Therefore, from another perspective, the active time is a receivable timefor the UE, which means that only data arrived in the receivable time can be received by the UE.

Mode 1: In SL resource allocation Mode 1, the base station (BS) schedules SL transmission resources to be used by UE for SL transmission.

Mode 2: In SL resource allocation Mode 2, different from Mode 1, UE autonomously selects on its own based on channel sensing (i.e. BS does not schedule) SL transmission resources within SL resources configured by BS/network or pre-configured SL resources.

Based on the above, technical schemes of the disclosure will be described below in detail. The technical solutions of implementations are applicable to various communication systems, for example, a global system of mobile communication (GSM) , a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, an LTE system, an LTE frequency division duplex (LTE-FDD) system, an LTE time division duplex (LTE-TDD) system, a universal mobile telecommunication system (UMTS) , or a 5 ^th generation (5G) system.

In the disclosure, various implementations are described in connection with a terminal device. The terminal device may refer to a user equipment (UE) , an access terminal, a subscriber unit, a subscriber station, a mobile station, a remote station, a remote terminal, a mobile device, a terminal, a wireless communication device, a user agent, or a user device. The access terminal may be a cellular radio telephone, a cordless telephone, a session initiation protocol (SIP) telephone, a wireless local loop (WLL) station, a personal digital assistant (PDA) , a handheld device with wireless communication functions, a computing device, other processing devices coupled with a wireless modem, an in-vehicle device, a wearable device, a terminal device in a 5G network, a terminal device in a future evolved public land mobile network (PLMN) , etc.

Specifically, the UE herein may include but is not limited to: vehicle to everything (V2X) communication system development vendors; automakers including cars, trains, trucks, buses, bicycles, moto-bikes, helmets, and etc.; drones (unmanned aerial vehicles) ; smartphone, smart watches, wireless earbuds, wireless headphones; smartphones, smart watches, wireless earbuds, wireless headphones; communication devices, remote control vehicles and robots for public safety use; augmented reality (AR) /virtual reality (VR) device for gaming, conference/seminar, education purposes; smart home appliances including TV, stereo, speakers, lights, door bells, locks, cameras, conferencing headsets, and etc.; smart factory and warehouse equipment including internet of things (IoT) devices, robots, robotic arms, and simply just between production machines.

In the disclosure, anetwork device, if any, may be a device for communicating with a terminal device. The network device may be, for example, a base transceiver station (BTS) in the GSM or in the CDMA system, or may be a NodeB (NB) in the WCDMA system, or may be an evolutional Node B (eNB or eNodeB) in the LTE system. Alternatively, the network device may be a relay station, an access point, an in-vehicle device, a wearable device, a network-side device in the 5G network, or a network device in the future evolved PLMN.

On the development of 5G-new radio (NR) based SL system, the radio technology was primarily designed to support wireless communication directly between terminal devices without the need of sending data information via a mobile cellular network to save time, which is known as device-to device (D2D) communication. The disclosed technical schemes generally relate to SL communication technology in the 3rd generation partner project (3GPP) NR Release 17 and beyond, for example providing cellular-V2X (C-V2X) communication. In V2X communication, X may generally refer to any device with wireless receiving and transmitting capabilities, for example (but not limited to) , a wireless device that moves slowly, a vehicle-mounted device that moves quickly, a network control node with wireless transmitting and receiving capabilities, or the like. It should be understood that implementations herein are mainly applied to a V2X communication scenario, but it can also be applied to any other device-device (D2D) communication scenario, which is not limited herein.

FIG. 1 is a schematic diagram illustrating an application scenario of implementations of the disclosure. FIG. 1 exemplarily illustrates one network device and two terminal devices. A wireless communication system may also include multiple network devices, and there can be other numbers of terminal devices in a coverage area of each of the network devices, which is not limited herein. In addition, the wireless communication system may further include a mobile management entity (MME) , or other network entities such as a serving gateway (S-GW) or a packet data network gateway (P-GW) , which is not limited herein. Terminal device 20 and terminal device 30 can communicate with each other through D2D communication. InD2D communication, terminal device 20 and terminal device 30 directly communicate with each other through a sidelink, that is, an SL. For example, as illustrated in FIG. 1, terminal device 20 and terminal device 30 communicate with each other through an SL, in which a transmission resource is selected by terminal device 20 and terminal device 30 instead of being allocated by the network device.

In D2D communication, spectrum resources are able to operate in areas without the network coverage. Traditionally, the usage/application of SL technology has been assuming that the terminal device has unlimited supply of battery/processing power, such as a road vehicle like a car, bus, truck or motorcycle, for V2X communication.

Besides this particular application, the NR SL radio technology can be also used for public safety backpack terminal users, vulnerable road users (VRUs) such as pedestrians, wearable devices connecting to a smartphone (e.g., smart watches, health care devices, AR/VR glasses, etc. ) . For these portable devices in various applications, the amount of processing power is often constrained by the battery size and no long assumed to be unlimited. In order to prolong the wireless communication time during device operation, one of main power saving mechanisms is to reduce or minimize the amount of SL signals and channels that the device needs to receive without significantly impacting the radio performance. Typically, radio channel sensing for resource allocation and receiving SL control and data channels consumes most of reception processing power in a NR SL UE.

For power efficient operation of a NR SL UE, power saving resource allocation (RA) mechanisms are being developed, which include random resource selection, partial sensing based (periodic and aperiodic/contiguous) resource selection, and SL discontinuous reception (DRX) . The use of these power saving RA mechanisms could be performed independently or jointly by a transmitter UE (Tx-UE) , depending on the configuration.

For example, a Tx-UE could be configured by its higher layer to perform random resource selection in a (pre-) configured SL resource pool and within a resource selection window (RSW) confined by the packet delay budget (PDB) of the data. The PDB can be described as an upper bound for the time that a packet may be delayed between the UE and the PCEF (Policy and Charging Enforcement Function) . As another example, a Tx-UE may be configured by its higher layer to perform partial sensing to select resources for transmission that needs to be delivered within a certain duration of a SL-DRX cycle of the intended target receiver UE (Rx-UE) .

For a resource (re) selection procedure triggered in a UE with SL data for transmission, the selection of a power saving RA mechanism to be used could be dependent on the type of SL traffic (periodic or aperiodic) , packet delay budget (PDB) , and whether the chosen SL resource pool allows reservation for another transport block (TB) /multiple periods. One of many challenging technical aspects relating to the design of resource (re) selection procedure is the ability for the transmitter UE (Tx-UE) to find appropriate (receivable by the target destination UE) and suitable (to avoid collision /interference with other UEs) resources for sending data information.

For example, it is not feasible to (pre-) configure SL-DRX cycle for a receiver UE (Rx-UE) in advance that will always match with Tx-UE’s traffic pattern, especially when the transmission type is aperiodic without a prior indication, because in aperiodic transmission, it is impossible to anticipate the arrival of a packet. Another challenge of selecting suitable resources for transmission is to also ensure there are sufficient channel sensing results from the partial sensing operation in order to accurately determine resource availability, and thus, avoiding resources that have been reserved in the past by other UEs, so as to avoid resource collision with other UEs. The sensing results here refers to selection or reservation of resources by other UEs in a resource pool. At the same time, the UE should also ensure there are sufficient number of resources for the final selection by the higher layer.

FIG. 2 is a schematic diagram illustrating resource set initialization in the relate art. Currently in NR sidelink, the UE shall assume that any set of contiguous sub-channels included in a corresponding resource pool within the time interval [n+T ₁, n+T ₂] correspond to one candidate single-slot resource, and a candidate resource set S _A is initialized to the set of all the candidate single-slot resources, as illustrated in FIG. 2. Thus, the candidate resource set S _A is initialized to include all resources in the resource selection window (RSW) , therefore, the candidate resource set S _Ainitialization is totally RSW based.

In FIG. 2 and other figures, n represents the triggering time slot for triggering resource (re-) selection, PDB represents packet delay budget, and RSW represents a resource selection window in which resources are selected. The RSW starts at n+T ₁and ends at n+T ₂.

FIG. 3 and FIG. 4 are further schematic diagrams illustrating current resource set initialization. If the candidate resource set S _A is initialized to the set of all the candidate single-slot resources within the RSW, as illustrated in FIG. 3, the resources falling within the dark area did not subject to PBPS, and there may be resource collision when such resources are selected or periodically reserved. On the other hand, if the candidate resource set S _A is initialized to the set of all the candidate single-slot resources within the RSW, as illustrated in FIG. 4, there is no time for the Tx-UE to perform CPS. Since no CPS is performed, the candidate resource set S _A may include resources which are selected or dynamically reserved by other UEs and therefore should be excluded, which may lead to resource collision.

It is desirable that each resource in the candidate resource set S _A has subjected to sensing and has a corresponding sensing result, that is, whether the resource has been selected or reserved by other UEs should have been determined, to avoid resource collation. In this regard, implementations of the disclosure provide a time/timing criteria based resource selection mechanism in SL communication, specifically, a time/timing criteria based resource set initialization mechanism, which further takes PBPS, CPS, and SL-DRX into consideration to optimize candidate resource set initialization. The resource selection mechanism provided herein is applicable to a scenario where a Tx-UE is configured by its higher layer to perform partial sensing to select resources for transmission that needs to be delivered within a certain duration of a SL-DRX cycle of the intended target receiver UE (Rx-UE) .

In NR SL communication under Mode 2 operation (a.k.a. “UE autonomous” or “selected” resource allocation mode) , there are two types of resource allocation schemes, namely periodic and aperiodic/dynamic reservations. When a Mode 2 or “selected” resource pool with a higher layer /RRC parameter sl-MultiReserveResource configured or enabled, both periodic and dynamic reservation of SL resources can be performed by a SL UE using sidelink control information (SCI) transmitted in physical sidelink control channel (PSCCH) . When the SL UE needs to transmit multiple data transport blocks (TBs) periodically, it indicates a resource reservation period value according to another (pre-) configured higher layer /RRC parameter sl-ResourceReservePeriodList. (e.g., 10ms, 25ms, 50ms, 75ms, 100ms, 200ms, 300ms, …1000ms) . In addition, the SL UE can also dynamically reserve resources for retransmission of the same TB by indicating up to 3 SL resources within 32 slots using the frequency and time resource assignment fields in SCI.

Since SL UEs are allowed to reserve resources periodically and dynamically in a Mode 2 resource pool, both periodic and aperiodic resource reservation should be monitored during partial sensing and taken into account as part of the mode resource (re) selection procedure. When an SL Mode 2 resource allocation procedure is triggered to report a subset of resources to the higher layer for PSCCH/physical sidelink shared channel (PSSCH) transmission and partial sensing is also configured by a higher layer (s) , PBPS should be performed by the Tx-UE to detect periodic SL resource reservation from other UEs in an SL resource pool and CPS should performed by the Tx-UE to detect dynamic SL resource reservations from other UEs in an SL resource pool.

In PBPS, a Tx-UE monitors periodically occurring sensing occasions that correspond to a set of Y candidate slots, which is selected by the Tx-UE within a resource selection window (RSW) . When a SL Mode 2 resource (re) selection procedure is triggered by a periodic transmission, the triggering time slot n is predictable and the packet delay budget is also known in advanced. Under such transmission conditions, prior monitoring of periodic sensing occasions before the resource (re) selection triggering slot is possible to be performed by the Tx-UE in advanced. As such, as long as the Y candidate slots are pre-selected for periodic transmissions within the RSW, full sensing results from PBPS are assumed to be available to the Tx-UE for the resource (re) selection procedure.

In CPS, a Tx-UE monitors a set of consecutive slots within an SL Mode 2 resource pool between [n+T _A, n+T _B] , where n is the resource (re) selection triggering slot timing (same as per PBPS) and T _A, T _B values are determined by the Tx-UE to detect dynamic resource reservations, which can be up to 32 slots. Therefore, logically T _B minus T _A should be equal to 31 slots in order to detect all possible dynamic resource reservations. Similar to PBPS, when an SL Mode 2 resource (re) selection procedure is triggered by a periodic traffic in slot n (for which the timing is predictable in advanced) , early contiguous partial sensing by the Tx-UE before the triggering slot timing n is also possible. On the other hand, if an SL Mode 2 resource (re) selection procedure is triggered by transmission of an aperiodic traffic, for which the generation of data packet is unpredictable in nature, the start of contiguous partial sensing is only possible after the triggering slot n.

Based on the above description of the intended purposes of a Tx-UE performing PBPS and CPS, and their corresponding operations, in order to maximize utilization of PBPS and CPS sensing results during a resource (re) selection procedure, in the present disclosure, a new method for initializing a set of candidate resources (S _A) during a resource selection procedure is provided. As mentioned before, when SL-DRX is (pre-) configured for the target/destination UE and known to the Tx-UE operating in NR SL resource allocation Mode 2, in determining the candidate resource set (S _A) , that is, in determining the length and timing location of the candidate resource set S _A, at least one or more slot timing/location related criteria should be met as followed.

Specifically, the candidate resource set S _A should be initialized to, that is, equal to the set of all candidate single-slot resources of the selected Y candidate slots from the PBPS, and the CPS sensing duration defined by the CPS monitoring window should be to 31 slots before the first slot of the selected Y candidate slots. When the target/destination UE (Rx-UE) is (pre-) configured with SL-DRX with a certain period cycle and length for the SL-DRX ON duration, then the Y candidate slots of the PBPS is to be selected to overlap with the SL-DRX active duration/time of the Rx-UE as much as possible. Specifically, Y candidate slots should be selected to overlap with the SL-DRX active duration time by at least N slots to ensure there are sufficient number of resources for selection within the receivable window/wake up time of the Rx-UE to achieve a minimal reception probability.

Therefore, in order to ensure SL data transmission from a Tx-UE is within the receivable time duration of the target destination Rx-UE and at the same time there is sufficient amount of channel sensing results to minimize transmission collision with other UEs, it is proposed in the present invention to initialize a candidate resource set (S _A) according to the following set of timing criteria during an SL Mode 2 resource (re) selection procedure. The timing criteria for which the Tx-UE should follow in initializing a set of candidate resource (S _A) during an SL Mode 2 resource (re) selection procedure when SL-DRX active duration/time of the Rx-UE is known include at least one of the followings.

Criterion 1: The candidate resource set S _A is initialized to overlap/include at least N slots of SL-DRX active duration/time of the Rx-UE. As such, it ensures the transmitted SL data is within the receivable time duration of the target/destination Rx-UE.

Criterion 2: The candidate resource set S _A is initialized to cover a period of time that allows a minimum monitoring window/length for CPS can be performed by the Tx-UE before the first slot of the candidate resource set S _A subject to UE processing time restrictions. As such, it ensures that there is sufficient amount of channel sensing results to minimize transmission collision with dynamic reservation from other UEs.

Criterion 3: The candidate resource set S _Ais initialized to cover a period of time that overlaps/includes at least a minimum number (Y _min) of slots for the Y candidate slots. As such, it ensures that there is sufficient amount of channel sensing results to minimize transmission collision with periodic reservation from other UEs, and the Tx-UE can ensure there are sufficient number of resources for the final selection by the higher layer.

By following the above 3 timing criteria, it is possible for the Tx-UE to find appropriate (receivable by the target destination Rx-UE) and suitable (to avoid collision /interference with other UEs) resources for sending data information.

Based on the above, in implementations, a method for candidate resource set initialization is provided. The method is performed by a Tx-UE in an SL mode 2 resource selection or reselection procedure.

FIG. 5 is a schematic flowchart illustrating the method for candidate resource set initialization provided in implementations. As illustrated in FIG. 5, the method includes: 501, initializing a candidate resource set S _A according to SL-DRX active time of a Rx-UE. The SL-DRX active time of the Rx-UE can be provided to the Tx-UE by a higher layer. Here, the candidate resource set S _Ais initialized at least considering the SL-DRX active time of the Rx-UE. Retransmission of the same data packet is minimized when the candidate resource set S _A for selection is confined within or overlaps with the receivable time region of the target/destination receiver Rx-UE (Rx-UE’s SL-DRX active time) .

Specifically, according to Criterion 1, the initializing in block 501 can include: initializing the candidate resource set S _A in such a manner that the candidate resource set S _A overlaps at least N slots of the SL-DRX active time of the Rx-UE. That is, the candidate resource set S _Ais initialized to overlap/include at least N slots of SL-DRX active duration/time of the Rx-UE. Hereinafter, we use N to represent minimum overlapping slots.

In some implementations, the value of N, that is, the minimum number of overlapping slots is pre-defined or (pre-) configured.

In some implementations, the value of N is determined according to a L1 priority level (e.g., prio _TX) . Specifically, N can be determined according to a L1 priority value. The L1 priority value can be provided to the Tx-UE by a higher layer. Generally, a lower L1 priority value corresponds to a larger value of N. Generally, a lower L1 priority value corresponds to a higher L1 priority level.

In some implementations, the value of N is based on a range of values. Specifically, the value of N is (pre-) configured from a range of values.

In one implementation, as illustrated in FIG. 5, the method may further include: 503, initializing the candidate resource set S _A according to a monitoring window for partial sensing. Here, the candidate resource set S _A is initialized at least considering the monitoring window for partial sensing.

According to Criterion 2, the above initializing in block 503 can include: initializing the candidate resource set S _A in such a manner that the candidate resource set S _Aallows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set S _A and UE processing time.

The monitoring window for partial sensing with a minimum length can be referred to as a minimum monitoring/sensing window for short. The partial sensing in this implementation is CPS and accordingly, the monitoring window for partial sensing is CPS monitoring window. Hereinafter, we use M to represent the minimum length of the CPS monitoring window.

In some implementations, the value of the minimum length M is configured or preconfigured. That is, the minimum monitoring window/length for CPS (M) is (pre-) configured.

In some implementations, the value of the minimum length M is determined according to a L1 priority value. The L1 priority value is provided to the Tx-UE by a higher layer. Specifically, a lower L1 priority value corresponds to a larger value of the minimum length M. In other words, M is determined based on a L1 priority level (prio _TX) , and generally, a higher priority level corresponds to a larger value of the minimum length M, that is, corresponds to a larger minimum CPS monitoring window.

In some implementations, the value of the minimum length M is determined according to remaining packet delay budget (PDB) or a percentage of remaining PDB. Generally, a larger remaining PDB or a larger percentage of remaining PDB corresponds to a larger M.

In some implementations, the value of the minimum length M is configured or preconfigured from a range of values.

In some implementations, the method further includes determining the monitoring window for partial sensing. In terms of the monitoring window for partial sensing, it can be expressed as [n+T _A, n+T _B] , where n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values to be determined by the Tx-UE. For example, the monitoring window is illustrated in FIG. 7 and 8.

In some implementations, as illustrated in FIG. 5, the method may further include: 505, initializing the candidate resource set S _Aaccording to a set of Y candidate slots, where Y is an integer and Y ≥ 1. Here, the candidate resource set S _A is initialized at least considering the candidate slots.

Specifically, according to Criterion 3, the initializing in 505 can include: initializing the candidate resource set S _A in such a manner that the candidate resource set S _Aoverlaps with at least a minimum number of slots in the set of Y candidate slots. In other words, the candidate resource set S _A is initialized to cover a period of time that overlaps/includes at least a minimum number of slots for the Y candidate slots. The minimum number is expressed as Y _min in the following.

By following Criterion 2 and Criterion 3, it is possible to minimize transmission collision/interference to other UEs, and thus maximize the SL communication reliability, with a guaranteed minimum channel monitoring time length and corresponding sensing results.

In some implementations, the minimum number for the Y candidate slots (Y _min) is (pre-) configured.

It should be noted that, in the above, for ease of explanation, operations at

block

501, 503, and 505 are described in turn, this however does not mean that there is any restriction on the order in which the above operations are performed. For example, operations at

block

501, 503, and 505 can each be performed separately. Alternatively, operations at block 501-505 can be performed simultaneously. Alternatively, operations at block 505 can be performed before

block

501 or 503. Still alternatively, operations at block 503 can be performed before 501 or after 505. This disclosure is not restricted in this regard.

The method for candidate resource set initialization in different transmission scenarios will be described below in detail.

Periodic Transmission

When the resource reservation interval parameter for PSCCH/PSSCH transmission has a non-zero value (i.e., P _{rsvp_TX}≠? for periodic transmission) , meaning the resource (re) selection trigger slot n is predictable by the Tx-UE, the selection of Y candidate slots for PBPS within the RSW and the monitoring window [n+T _A, n+T _B] in CPS can be flexibly determined by the Tx-UE (not restricted by the triggering slot time) , since UE monitoring of periodic sensing occasions in PBPS and a set of consecutive slots in CPS could be performed in advanced prior to the triggering slot n as described previously. Therefore, when there are at least N minimum number of slots from the Rx-UE’s SL-DRX active time located within the RSW of the triggered resource (re) selection procedure, all of the above timing criteria 1-3 for initializing the candidate resource set (S _A) would be met by the Tx-UE.

FIG. 6 is a schematic flowchart illustrating candidate resource set initialization for periodic transmission. FIG. 7 is an exemplary illustration of the proposed method for initializing a set of candidate resources (S _A) for periodic SL transmission when Rx-UE’s SL-DRX active time is provided. As illustrated in FIG. 7, the Rx-UE’s SL-DRX active time 701 is provided to the Tx-UE by a higher layer.

As illustrated in FIG. 6, an exemplary illustration of the proposed method for selecting Y candidate slots in PBPS (601) , determining the monitoring window in CPS (603) , and initializing a candidate resource set (S _A) (605) when SL-DRX is configured for the Rx-UE is depicted. In various implementations, the illustrated process blocks in FIG. 6 may be broken up, merged, or omitted. In one implementation, this method is done through the Tx-UE.

The method for candidate resource set initialization is further detailed in FIG. 7, in which the proposed method 700 is depicted.

Firstly, assuming the SL resource pool is (pre-) configured with sl-MultiReserveResource set to ‘enabled’ and the resource reservation interval parameter provided by the higher layer to trigger an SL Mode 2 resource allocation procedure has a non-zero value for periodic reservation and transmission (i.e., P _{rsvp_TX}≠0) . That is, the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter not equal to zero and a higher layer parameter sl-MultiReserveResource configured.

Secondly, in terms of selecting (601) Y candidate slots in PBPS, further assume that the target/destination Rx-UE is configured with SL-DRX for which it has a SL-DRX active time 701 that overlaps with the resource selection window [n+T ₁, n+T ₂] 702 of the triggered resource allocation procedure. As explained previously, since the resource (re) selection trigger is periodic and predictable, the selection of Y candidate slots in PBPS and the monitoring window in CPS ( “CPS monitoring window” for short) can be flexibly determined by the Tx-UE. As such, in order to fulfill the proposed timing criteria of the present invention, as part of the PBPS processing, the UE should select Y candidate slots 703, the Y candidate slots 703 includes at least a minimum number (Y _min) of slots. That is, the Y candidate slots 703 has a minimum length of Y _minslots 704 to overlap with Rx-UE’s SL-DRX active time 701 for at least a minimum of N slots 705.

Determination (603) of the monitoring window in CPS will be described in the following, with reference to FIG. 7. For the CPS process, since the resource (re) selection trigger timing is predictable and known by the Tx-UE in advanced, the Tx-UE is able to start performing CPS earlier than the triggering slot n. The CPS monitoring window (708) can be expressed as [n+T _A, n+T _B] , as described before. In this case, T _A for the start of CPS monitoring window (n+T _A) 706 has a negative value. The end of CPS monitoring window (n+T _B) 707 should be set just before the first slot of the set of Y candidate slots 703, subject to UE processing time restrictions, to obtain the most recent sensing results for the candidate slots. In order to detect as many dynamic resource reservations as possible from other UEs to avoid transmission collision, the CPS monitoring window 708 should be set as large as possible or at least more than a minimum of M slots (i.e., M ≤ T _B–T _A ≤ 31 slots) .

If using the first slot of the set of Y candidate slots as the reference point (i.e., denote t _y0as the first candidate slot for the resource selection) , then the exact timing slot for the said CPS monitoring window 708 can be determined as: n + T _B =t _y0 –T _proc, 0 –T _proc, 1, where T _proc, 0represents a processing time for monitoring physical PSCCH by the Tx-UE, and T _proc, 1represents a processing time for preparation of PSCCH/PSSCH transmission by the Tx-UE.

In some implementations, n + T _A = n + T _B –31, and/or M ≤ T _B–T _A ≤ 31, where M represents the minimum length of the CPS monitoring window.

Once the set of Y candidate slots 703 and the CPS monitoring window 708 are determined, in 605 in FIG. 6, the candidate resource set S _A 709 for the triggered resource (re) selection procedure should be initialized to (that is, equal to) the set of all candidate single-slot resources of the Y candidate slots selected from PBPS 703 to maximally utilize the partial sensing results from PBPS and CPS, and at the same time, the candidate resource set S _A 709covers at least N slots 705 of Rx-UE’s SL-DRX active time 701.

To be summarized, when the SL Mode 2 resource (re) selection procedure is triggered for PSCCH/PSSCH transmission with the resource reservation interval parameter not equal to zero, P _{rsvp_TX}≠0, the resource pool provided by higher layer is configured with sl-MultiReserveResource, and SL-DRX active duration/time is known to the Tx-UE, (i) the set of Y candidate slots of periodic-based partial sensing includes at least a minimum of Y _min number of slots, (ii) the set of Y candidate slots is selected to overlap with SL-DRX active duration/time of the target destination Rx-UE for at least a minimum of N number of slots, and (iii) the candidate resource set S _A is initialized to the set of all candidate single-slot resources of the selected Y candidate slots.

Aperiodic transmission

Another transmission scenario is when the resource reservation interval parameter for PSCCH/PSSCH transmission has a zero value (i.e., P _{rsvp_TX}=0 for aperiodic transmission) . FIGs. 8-10 are exemplary illustrations of the proposed method for initializing a set of candidate resources (S _A) for aperiodic SL transmission when Rx-UE’s SL-DRX active time is provided. In this transmission scenario, the resource (re) selection trigger slot n is no longer predictable and cannot be known in advanced by the Tx-UE.

In this case, it is not possible for the Tx-UE to perform monitoring of periodic sensing occasions in advanced before the triggering slot n if a new set of Y candidate slots is selected. Moreover, the Tx-UE is not able to start performing SL resource monitoring for CPS before the resource (re) selection triggering (triggering time slot n) for aperiodic transmission either. As such, in order to detect periodic and dynamic resource reservations from other UEs in the same resource pool, the Tx-UE can only rely on partial sensing results for an existing set of Y candidate slots of an on-going PBPS and perform CPS monitoring after the resource (re) selection triggering slot. Additionally, if the target/destination Rx-UE is already configured with SL-DRX, there is no guarantee that: (i) SL-DRX active time of the Rx-UE has any overlapping slots with the existing Y candidate slots, for example, as illustrated in FIG. 8, the Rx-UE’s SL-DRX active time of the Rx-UE has no overlapping slot with the existing Y candidate slots, (ii) there is sufficient number (Y _min) of Y candidate slots located within the RSW, for example, as illustrated in FIG. 9, there is not sufficient number of Y candidate slots located within the RSW, and/or (iii) there is a sufficient time for the Tx-UE to perform CPS for SL resource monitoring for at least a minimum window length of M slots, for example, as illustrated in FIG. 10, there is not sufficient time for the Tx-UE to perform CPS for SL resource monitoring for at least a minimum window length of M slots, because the CPS should be performed after the triggering time slot n and before the first slot of the candidate resource set S _A.

Due the above reasons and possible scenarios that could occur, it may not be possible that the above 3 timing criteria proposed in the present disclosure can be always met in all operating conditions. Therefore, it is further proposed that when SL resource (re) selection procedure is triggered by aperiodic traffic transmission (i.e., P _{rsvp_TX}=0) for a higher layer provided resource pool with a higher layer /RRC parameter sl-MultiReserveResource configured or enabled and the target/destination Rx-UE is configured with SL-DRX, if not all of the 3 proposed timing criteria for selecting a candidate resource set (S _A) or candidate resource set (S _A) initialization can be met, then the above first described timing criterion (Criterion 1) related to ensuring the candidate resource set S _A is initialized to overlap/include at least N slots of SL-DRX active time of the Rx-UE should be given the highest priority to be satisfied. It is then followed by the above second described timing criterion (Criterion 2) related to ensuring a minimum monitoring window/minimum length for CPS can be performed by the Tx-UE before the first slot of S _A as a second priority. Alternatively, Criterion 1 can be followed by Criterion 3 to make sure that there is at least Y _min number of slots from a PBPS and there are still at least N slots from the Rx-UE’s SL-DRX active time available for the resource (re) selection. Or it is up to UE implementation to decide which one of the above Criterion 2 and Criterion 3 to satisfy when only one of them can be met, the disclosure is not limited thereto.

As such, when the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided, a method for candidate resource set initialization in the SL mode 2 resource selection or reselection procedure includes: initializing (FIG. 5, 503) a candidate resource set according to a monitoring window for partial sensing. Specifically, the candidate resource set is initialized such that the candidate resource set allows a monitoring window for partial sensing with a minimum length M. The monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In some implementations, the partial sensing is CPS and accordingly, the monitoring window for partial sensing is a CPS monitoring window.

In some implementation, the value of the minimum length M is configured or preconfigured.

In some implementations, the value of the minimum length M is determined according to a L1 priority value. In some implementations, the L1 priority value is provided to the Tx-UE by a higher layer. In some implementations, generally, a lower L1 priority value corresponds to a larger value of the minimum length M.

In some implementations, the value of the minimum length M is determined according to remaining PDB or a percentage of remaining PDB. Generally, a larger remaining PDB corresponds to a larger value of the minimum length M.

In some implementations, the value of the minimum length M is configured or preconfiguredfrom a range of values.

In some implementations, the method further includes: determining the monitoring window as [n+T _A, n+T _B] , where n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values to be determined by the Tx-UE. T _A and T _B satisfy at least one of the following expressions.

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, where t _y0represents a first slot in the set of Y candidate slots, Y is an integer and Y ≥ 1; T _proc, 0 represents a processing time for monitoring PSCCH by the Tx-UE, and T _proc, 1represents a processing time for preparation of PSCCH/PSSCH transmission by the Tx-UE.

T _A ≥ 1.

M ≤T _B–T _A ≤31.

Furthermore, when the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided, another method for candidate resource set initialization in the SL mode 2 resource selection or reselection procedure includes: initializing (FIG. 5, 505) a candidate resource set S _A according to a set of Y candidate slots, where Y is an integer and Y ≥ 1.

Specifically, the candidate resource set S _A is initialized such that the candidate resource set overlaps at least a minimum number (Y _min) of slots in the set of Y candidate slots that are located within a resource selection window. In some implementations, the minimum number Y _min is configured or preconfigured. In some implementations, the set of Y candidate slots at least includes the minimum number of slots Y _min. In some implementations, the set of Y candidate slots are selected in PBPS. In some implementations, the set of Y candidate slots are selected to overlap at least N slots of SL-DRX active time of a Rx-UE, where N is an integer and N ≥ 1, and the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.

The above two methods, which are depicted with reference to the scenario where the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided, although described separately, can be executed jointly and the execution order is not limited. These two methods can be executed simultaneously or successively.

In reference to FIG. 8, an exemplary illustration of the proposed method 800 for initializing a candidate resource set (S _A) for aperiodic SL transmission when SL-DRX is configured for the Rx-UE is depicted.

Firstly, assuming the SL resource pool is (pre-) configured with sl-MultiReserveResource set to ‘enabled’ and the resource reservation interval parameter provided by the higher layer to trigger a SL Mode 2 resource allocation procedure has a zero value for aperiodic transmission (i.e., P _{rsvp_TX}=0) .

Secondly, assume SL-DRX active time of the target /destination Rx-UE 801 overlaps with the resource selection window [n+T ₁, n+T ₂] 802 for more than the minimum N slots 803. Moreover, there is an existing set of Y candidate slots 804 from an on-going PBPS that partially overlaps/falls within the said RSW 802. As explained previously, since the resource (re) selection trigger is aperiodic and unpredictable, the Tx-UE is only able to start CPS monitoring of SL resources after the resource (re) selection trigger in slot n (n represents the triggering time slot) . Since the timing position of the existing Y candidate slots and Rx-UE’s SL-DRX active time 801 cannot be altered, the Tx-UE should initialize the candidate resource set S _A 805 firstly to cover at least N minimum slots 803of the Rx-UE’s SL-DRX active time 801.

Since there are at least Y _min slots 807 from the existing set of Y candidate slots 804 located within the RSW 802, the initialized candidate resource set S _A 805 should cover all slots from the existing Y candidate slots 804 that are located within the RSW. Moreover, suppose the CPS monitoring window 806 is determined as [n+T _A, n+T _B] , for example, at block 603 in FIG. 6. If there are sufficient number of slots after the resource (re) selection trigger slot n for CPS monitoring window [n+T _A, n+T _B] 806, then the first slot of the candidate resource set S _A 805should be selected at a timing (e.g., in slot n+T _B+T _proc, 0+T _proc, 1) such that there are at least N minimum slots included in the candidate resource set S _A, where T _B –T _A ≥ M and/or T _A ≥ 1.

To be summarized, when the SL Mode 2 resource (re) selection procedure is triggered for PSCCH/PSSCH transmission with the resource reservation interval parameter equal to zero, P _{rsvp_TX}=0 or not provided at all, and SL-DRX active duration/time is known to the Tx-UE, at least one of the 3 timing criteria should be met or satisfied. For example, the first timing criterion to be satisfied is to ensure the candidate resource set S _A is initialized to overlap /include at least N slots of SL-DRX active time of the target destination Rx-UE (Criterion 1) , the second timing criterion to be satisfied is to ensure a minimum monitoring window length of M slots for partial sensing can be performed by the Tx-UE before the first slot of S _A (Criterion 2) , or the second timing criterion to be satisfied is to ensure that the candidate resource set S _A is initialized to cover a time period that overlaps/includes with at least a minimum number of Y _min slots of a set of Y candidate slot (Criterion 3) .

For example, in FIG. 8, all the 3 timing criteria are satisfied. In FIG. 9, Criterion 1 and Criterion 2 are satisfied. In FIG. 10, Criterion 1 and Criterion 3 are satisfied.

In initializing the candidate resource set S _A, by taking the Rx-UE’ SL-DRX active time, PBPS, and CPS into consideration, it is possible to ensure that there are sufficient channel sensing results from the partial sensing operation in order to accurately determine resource availability, and thus, avoiding selecting resources that have been reserved in the past by other UEs. As such, the candidate resource set initialized has increased reliability, and the increased reliability means better performance and greater user experience of the Tx-UE. Furthermore, lower power consumption for SL communication can be also achieved from reduced number of retransmissions due to collision avoidance means longer operating time for the Tx-UE.

Implementations of the disclosure further provide a device for candidate resource set initialization. The device can be used by the Tx-UE to achieve the method for candidate resource set initialization described in the above implementations.

A device 110 for candidate resource set initialization is used for a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure is provided. As illustrated in FIG. 11, the device 110 includes a processing unit 112. In some implementations, the device 110 may further include a transceiver unit 114. The processing unit 112 is coupled with the transceiver unit 114. The device 110 is applicable when the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter not equal to zero and a higher layer parameter sl-MultiReserveResource configured, and/or when the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided.

The processing unit 112 is configured to initialize a candidate resource set according to SL-DRX active time of a receiver user equipment (Rx-UE) . Specifically, the processing unit 112 is configured to initialize the candidate resource set in such a manner that the candidate resource set overlaps at least N slots of the SL-DRX active time of the Rx-UE, whereN is an integer and N ≥ 1. The SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer of the Tx-UE for example through the transceiver unit 114.

In some implementations, the value of N is configured or preconfigured, and/or the value of N is determined according to a L1 priority value, and/or the value of N is configured or preconfigured from a range of values. The L1 priority value can be provided to the Tx-UE by a higher layer of the Tx-UE for example through the transceiver unit 114. Generally, a lower L1 priority value corresponds to a larger value of N.

In some implementations, the processing unit 112 is further configured to: initialize the candidate resource set according to a monitoring window for partial sensing. Specifically, the processing unit 112 is configured to: initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.

In some implementations, the partial sensing is contiguous partial sensing (CPS) and the monitoring window for partial sensing is a CPS monitoring window. The value of the minimum length is configured or preconfigured, and/or the value of the minimum length is determined according to a L1 priority value, and/or the value of the minimum length is determined according to remaining PDB or a percentage of remaining PDB, and/or the value of the minimum length is configured or preconfigured from a range of values. Generally, a lower L1 priority value corresponds to a larger value of the minimum length. Generally, a larger remaining PDB corresponds to a larger value of the minimum length.

In some implementations, the processing unit 112 is further configured to: determine the monitoring window for partial sensing as [n+T _A, n+T _B] , where n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values to be determined by the Tx-UE.

At least one of the following expressions is satisfied.

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, where t _y0 represents a first slot in a set of Y candidate slots, whereY is an integer and Y ≥ 1; T _proc, 0 represents a processing time for monitoring PSCCH by the Tx-UE; and T _proc, 1 represents a processing time for preparation of PSCCH /PSSCH transmission by the Tx-UE.

n + T _A= n + T _B –31.

M ≤T _B–T _A ≤31, M represents the minimum length of the monitoring window for partial sensing.

In some implementations, the processing unit 112 is further configured to: initialize the candidate resource set according to a set of Y candidate slots, where Y is an integer and Y ≥ 1. Specifically, the processing unit 112 is configured to: initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots. The minimum number can be configured or preconfigured. Alternatively, the processing unit 112 is configured to: initialize the candidate resource set in such a manner that the candidate resource set is equal to all candidate single-slot resources in the set of Y candidate slots.

In some implementations, the processing unit 112 is further configured to: select a set of Y candidate slots, whereY is an integer and Y ≥ 1. The set of Y candidate slots includes at least a minimum number of slots. Specifically, the processing unit 112 is configured to: select the set of Y candidate slots in such a manner that the set of candidate slots overlaps at least N slots of the SL-DRX active time of the Rx-UE. The set of Y candidate slots are selected in periodic-based partial sensing (PBPS) .

According implementations of the disclosure, another device 110 for candidate resource set initialization is provided. The device used for a Tx-UE in the SL mode 2 resource selection or reselection procedure. Specifically, the device is applicable when the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided.

In this device 110, the processing unit 112 is configured to initialize a candidate resource set according to a monitoring window for partial sensing. Specifically, the processing unit 112 is configured to initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, where the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time. The partial sensing can be CPS and the monitoring window for partial sensing can be a CPS monitoring window.

In some implementations, a value of the minimum length is configured or preconfigured, and/or a value of the minimum length is determined according to a L1 priority value, and/or a value of the minimum length is determined according to remaining PDB or a percentage of remaining PDB, and/or, a value of the minimum length is configured or preconfiguredfrom a range of values. For example, the L1 priority value is provided to the Tx-UE by a higher layer. Generally, a lower L1 priority value corresponds to a larger value of the minimum length, similarly, a larger remaining PDB corresponds to a larger value of the minimum length.

In some implementations, the processing unit is further configured to: determine the monitoring window as [n+T _A, n+T _B] , wheren represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values determined by the Tx-UE.

At least one of the following expressions is satisfied.

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, where t _y0 represents a first slot in a set of Y candidate slots, whereY is an integer and Y ≥ 1; T _proc, 0 represents a processing time for monitoring PSCCH by the Tx-UE; and T _proc, 1 represents a processing time for preparation of PSCCH/PSSCH transmission by the Tx-UE.

T _A ≥ 1.

In this device 110, the processing unit 112 is configured to initialize a candidate resource set according to a set of Y candidate slots, whereY is an integer and Y ≥ 1. Specifically, the processing unit 112 is configured to: initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots that are located within a resource selection window. The minimum number can be configured or preconfigured. The set of Y candidate slots at least includes the minimum number of slots, and the set of Y candidate slots are selected in PBPS.

In some implementations, the set of Y candidate slots are selected to overlap at least N slots of SL-DRX active time of a Rx-UE, whereN is an integer and N ≥ 1, and the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.

Various implementations and/or technical features of the various implementations may be implemented in any combination with each other without conflict, and technical solutions thus obtained shall also fall within the protection cope of the disclosure.

Implementations further provide a UE. The UE can be the Tx-UE in an SL mode 2 resource selection or reselection procedure. FIG. 12 is a schematic block diagram illustrating the UE. The UE 120 illustrated in FIG. 12 includes a processor 122 and a memory 124 coupled with the processor 122. The processor 122 is configured to invoke and run the computer program stored in the memory to perform the method described above, such as the method illustrated in FIG. 5, FIG. 6, FIG. 7, FIG. 8-FIG. 10. The UE 120 may further include a transceiver 126 for transmitting or receiving information or data from outsideor from other components of the UE, such as from a higher layer. The information transmitted may include the higher layer parameter sl-MultiReserveResource, the L1 priority value, the resource reservation interval parameter, and other parameters based on which the candidate resource set is initialized. The processor 122, the memory 124, and the transceiver 126 are coupled to a bus for communication.

Implementations further provide a chip. The chip can be equipped in the Tx-UE in an SL mode 2 resource selection or reselection procedure. FIG. 13 is a schematic block diagram illustrating the chip. As illustrated in FIG. 13, a chip 130 includes a processor 132 and a memory 134. The processor 132 is configured to invoke and execute computer programs stored in the memory 134 to perform the method provided in implementations. For details of the implementations, reference can be made to the foregoing description, which will not be repeated herein for the sake of simplicity. The memory 134 may be a device separated from the processor 132, or may be integrated into the processor 132.

As illustrated in FIG. 13, the chip 130 may further include an input interface 136. The processor 132 can control the input interface 136 to communicate with other devices or chips, for example, to acquire information or data sent by other devices or chips. For example, the processor 132 can communicate with a higher layer of the UE through the input interface 136 to obtain SL resource selection related information, such as the higher layer parameter sl-MultiReserveResource, the L1 priority value, the resource reservation interval parameterused herein. The chip 130 may further include an output interface 138. The processor 132 can control the output interface 138 to communicate with other devices or chips, for example, to output information or data to other devices or chips.

The chip 130 herein may also be referred to as a system-on-chip (SOC) .

The processor referred to herein may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the foregoing method implementations may be completed by an integrated logic circuit in the form of hardware or an instruction in the form of software in the processor. The processor may be a general-purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) , or other programmable logic devices, discrete gates or transistor logic devices, or discrete hardware components, which can implement or executethe methods, steps, and logic blocks disclosed in implementations. The general purpose processor may be a microprocessor, or the processor may be any conventional processor or the like. The steps of the method disclosed in implementations may be implemented through a hardware decoding processor, or may be performed by hardware and software modules in the decoding processor. The software module can be located in a storage medium such as a random access memory (RAM) , a flash memory, a read only memory (ROM) , a programmable ROM (PROM) , or an electrically erasable programmable memory, registers, and the like. The storage medium is located in the memory. The processor reads the information in the memory, and completes the steps of the method described above with the hardware of the processor.

The memory according to implementations may be a volatile memory or a non-volatile memory, or may include both the volatile memory and the non-volatile memory. The non-volatile memory may be a ROM, a PROM, an erasable programmable read only memory (erasable PROM, EPROM) , an electrically erasable programmable read only memory (electrically EPROM, EEPROM) , or flash memory. The volatile memory can be a RAM that acts as an external cache. By way of example but not limitation, many forms of RAM are available, such as a static RAM (SRAM) , a dynamic RAM (DRAM) , a synchronous DRAM (SDRAM) , a double data rate SDRAM (DDR SDRAM) , an enhanced SDRAM (ESDRAM) , a synchronous link DRAM (synch-link DRAM, SLDRAM) , and a direct rambus RAM (DRRAM) . The memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

Implementations further provide a computer readable storage medium. The computer readable storage medium is configured to store computer programs. The computer readable storage medium is applicable to the Tx-UE or the device for candidate resource set initialization. The computer programs, when executed, are operable with a computer to implement the operations performed by the Tx-UEor the d device for candidate resource set initialization described in the foregoing implementations, which will not be repeated herein for the sake of simplicity.

Implementations further provide a computer program product. The computer program product includes computer program instructions. The computer program product is applicable to Tx-UE or the device for candidate resource set initialization The computer program instructions, when executed, are operable with a computer to implement the operations performed by the Tx-UEor the d device for candidate resource set initialization described in the foregoing implementations, which will not be repeated herein for the sake of simplicity.

Implementations further provide a computer program. The computer program is applicable to the first terminal device of implementations. The computer program, when executed by a computer, is operable with the computer to implement the operations performed by the Tx-UEor the d device for candidate resource set initialization described in the foregoing implementations, which will not be repeated herein for the sake of simplicity.

The term “and/or” herein only describes an association relationship between associated objects, which means that there can be three relationships. For example, A and/or B can mean A alone, both A and B exist, and B alone. In addition, the character “/” herein, unless otherwise specified, generally indicates that the associated objects are in an “or” relationship.

While the disclosure has been described in connection with certain embodiments, it is to be understood that the disclosure is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation.

Claims

A method for candidate resource set initialization, performed by a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

initializing a candidate resource set according to SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE) .
The method of claim 1, wherein initializing the candidate resource set according to the SL-DRX active time comprises:

initializing the candidate resource set in such a manner that the candidate resource set overlaps at least N slots of the SL-DRX active time of the Rx-UE, wherein N is an integer and N≥1.
The method of claim 2, wherein the value of N is configured or preconfigured.
The method of claim 2, wherein the value of N is determined according to a L1 priority value.
The method of claim 4, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The method of claim 4, wherein a lower L1 priority value corresponds to a larger value of N.
The method of claim 2, wherein the value of N is configured or preconfigured from a range of values.
The method of any of claims 1 to 7, wherein the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.
The method of any of claims 1 to 8, further comprising:

initializing the candidate resource set according to a monitoring window for partial sensing.
The method of claim 9, wherein initializing the candidate resource set according to a monitoring window for partial sensing comprising:

initializing the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, wherein the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.
The method of claim 9 or 10, wherein the partial sensing is contiguous partial sensing (CPS) and the monitoring window for partial sensing is a CPS monitoring window.
The method of claim 10 or 11, wherein a value of the minimum length is configured or preconfigured.
The method of claim 10 or 11, wherein a value of the minimum length is determined according to a L1 priority value.
The method of claim 13, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The method of claim 13, wherein a lower L1 priority value corresponds to a larger value of the minimum length.
The method of claim 10 or 11, wherein a value of the minimum length is determined according to remaining packet delay budget (PDB) or a percentage of remaining PDB.
The method of claim 16, wherein a larger remaining PDB corresponds to a larger value of the minimum length.
The method of claim 10 or 11, wherein a value of the minimum length is configured or preconfigured from a range of values.
The method of any of claims 9 to 18, further comprising:

determining the monitoring window for partial sensing as [n+T _A, n+T _B] , wherein n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values determined by the Tx-UE.
The method of claim 19, wherein

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, wherein

t _y0 represents a first slot in a set of Y candidate slots, wherein Y is an integer and Y≥1;

T _proc, 0 represents a processing time for monitoring physical sidelink control channel (PSCCH) by the Tx-UE; and

T _proc, 1 represents a processing time for preparation of PSCCH/physical sidelink shared channel (PSSCH) transmission by the Tx-UE.
The method of claim 19 or 20, wherein n + T _A= n + T _B –31.
The method of any of claims 19 to 21, wherein M ≤T _B–T _A ≤31, M represents the minimum length of the monitoring window for partial sensing.
The method of any of claims 1 to 22, further comprising:

initializing the candidate resource set according to a set of Y candidate slots, wherein Y is an integer and Y ≥ 1.
The method of claim 23, wherein initializing the candidate resource set according to the set of Y candidate slots comprises:

initializing the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots.
The method of claim 24, wherein the minimum number is configured or preconfigured.
The method of claim 23, wherein initializing the candidate resource set according to the set of Y candidate slots comprises:

initializing the candidate resource set in such a manner that the candidate resource set is equal to all candidate single-slot resources in the set of Y candidate slots.
The method of any of claims 1 to 8, further comprising:

selecting a set of Y candidate slots, wherein Y is an integer and Y ≥1.
The method of claim 27, wherein the set of Y candidate slots comprises at least a minimum number of slots.
The method of claim 27, wherein selecting the set of Y candidate slots comprises:

selecting the set of Y candidate slots in such a manner that the set of candidate slots overlaps at least N slots of the SL-DRX active time of the Rx-UE.
The method of any of claims 27 to 29, wherein the set of Y candidate slots are selected in periodic-based partial sensing (PBPS) .
The method of any of claims 1 to 30, wherein the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter not equal to zero and a higher layer parameter sl-MultiReserveResource configured.
The method of any of claims 1 to 30, wherein the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided.
A method for candidate resource set initialization, performed by a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

initializing a candidate resource set according to a monitoring window for partial sensing.
The method of claim 33, wherein initializing the candidate resource set according to the monitoring window for partial sensing comprising:

initializing the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, wherein the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.
The method of claim 33 or 34, wherein the partial sensing is contiguous partial sensing (CPS) and the monitoring window for partial sensing is a CPS monitoring window.
The method of claim 34 or 35, wherein a value of the minimum length is configured or preconfigured.
The method of claim 34 or 35, wherein a value of the minimum length is determined according to a L1 priority value.
The method of claim 37, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The method of claim 37, wherein a lower L1 priority value corresponds to a larger value of the minimum length.
The method of claim 34 or 35, wherein a value of the minimum length is determined according to remaining packet delay budget (PDB) or a percentage of remaining PDB.
The method of claim 40, wherein a larger remaining PDB corresponds to a larger value of the minimum length.
The method of claim 34 or 35, wherein a value of the minimum length is configured or preconfiguredfrom a range of values.
The method of any of claims 33 to 42, further comprising:

determining the monitoring window as [n+T _A, n+T _B] , wherein n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values determined by the Tx-UE.
The method of claim 43, wherein

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, wherein

t _y0 represents a first slot in a set of Y candidate slots, wherein Y is an integer and Y≥1;

T _proc, 0 represents a processing time for monitoring physical sidelink control channel (PSCCH) by the Tx-UE; and

T _proc, 1 represents a processing time for preparation of PSCCH/physical sidelink shared channel (PSSCH) transmission by the Tx-UE.
The method of claim 43 or 44, wherein T _A ≥ 1.
The method of any of claims 43 to 45, wherein M ≤T _B–T _A ≤31, Mrepresents the minimum length of the monitoring window for partial sensing.
A method for candidate resource set initialization, performed by a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

initializing a candidate resource set according to a set of Y candidate slots, wherein Y is an integer and Y ≥ 1.
The method of claim 47, wherein initializing the candidate resource set according to the set of Y candidate slots comprises:

initializing the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots that are located within a resource selection window.
The method of claim 48, wherein the minimum number is configured or preconfigured.
The method of claim 48, wherein the set of Y candidate slots at least comprises the minimum number of slots.
The method of any of claims 47 to 50, wherein the set of Y candidate slots are selected in periodic-based partial sensing (PBPS) .
The method of claim 51, wherein the set of Y candidate slots are selected to overlap at least N slots of SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE) , wherein N is an integer and N ≥ 1, and the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.
A device for candidate resource set initialization, used for a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

a processing unit, configured to initialize a candidate resource set according to SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE) .
The device of claim 53, wherein the processing unit configured to initialize the candidate resource set according to the SL-DRX active time is configured to:

initialize the candidate resource set in such a manner that the candidate resource set overlaps at least N slots of the SL-DRX active time of the Rx-UE, wherein N is an integer and N ≥ 1.
The device of claim 54, wherein the value of N is configured or preconfigured.
The device of claim 54, wherein the value of N is determined according to a L1 priority value.
The device of claim 56, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The device of claim 56, wherein a lower L1 priority value corresponds to a larger value of N.
The device of claim 54, wherein the value of N is configured or preconfigured from a range of values.
The device of any of claims 53 to 59, wherein the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.
The device of any of claims 53 to 60, wherein the processing unit is further configured to:

initialize the candidate resource set according to a monitoring window for partial sensing.
The device of claim 61, wherein the processing unit configured to initialize the candidate resource set according to the monitoring window for partial sensing is configured to:

initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, wherein the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.
The device of claim 61 or 62, wherein the partial sensing is contiguous partial sensing (CPS) and the monitoring window for partial sensing is a CPS monitoring window.
The device of claim 62 or 63, wherein a value of the minimum length is configured or preconfigured.
The device of claim 62 or 63, wherein a value of the minimum length is determined according to a L1 priority value.
The device of claim 65, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The device of claim 65, wherein a lower L1 priority value corresponds to a larger value of the minimum length.
The device of claim 62 or 63, wherein a value of the minimum length is determined according to remaining packet delay budget (PDB) or a percentage of remaining PDB.
The device of claim 68, wherein a larger remaining PDB corresponds to a larger value of the minimum length.
The device of claim 62 or 63, wherein a value of the minimum length is configured or preconfigured from a range of values.
The device of any of claims 61 to 70, wherein the processing unit is further configured to:

determine the monitoring window for partial sensing as [n+T _A, n+T _B] , wherein n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values determined by the Tx-UE.
The device of claim 71, wherein

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, wherein

t _y0 represents a first slot in a set of Y candidate slots, wherein Y is an integer and Y≥1;

T _proc, 0 represents a processing time for monitoring physical sidelink control channel (PSCCH) by the Tx-UE; and

T _proc, 1 represents a processing time for preparation of PSCCH /physical sidelink shared channel (PSSCH) transmission by the Tx-UE.
The device of claim 71 or 72, wherein n + T _A= n + T _B –31.
The device of any of claims 71 to 73, wherein M ≤T _B–T _A ≤31, M represents the minimum length of the monitoring window for partial sensing.
The device of any of claims 53 to 74, wherein the processing unit is further configured to:

initialize the candidate resource set according to a set of Y candidate slots, wherein Y is an integer and Y ≥ 1.
The device of claim 75, wherein the processing unit configured to initialize the candidate resource set according to the set of Y candidate slots is configured to:

initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots.
The device of claim 76, wherein the minimum number is configured or preconfigured.
The device of claim 75, wherein the processing unit configured to initialize the candidate resource set according to the set of Y candidate slots is configured to:

initialize the candidate resource set in such a manner that the candidate resource set is equal to all candidate single-slot resources in the set of Y candidate slots.
The device of any of claims 53 to 60, wherein the processing unit is further configured to:

select a set of Y candidate slots, wherein Y is an integer and Y ≥ 1.
The device of claim 79, wherein the set of Y candidate slots comprises at least a minimum number of slots.
The device of claim79, wherein the processing unit configured to select the set of Y candidate slots is configured to:

select the set of Y candidate slots in such a manner that the set of candidate slots overlaps at least N slots of the SL-DRX active time of the Rx-UE.
The device of any of claims 79 to 81, wherein the set of Y candidate slots are selected in periodic-based partial sensing (PBPS) .
The device of any of claims 53 to 82, wherein the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter not equal to zero and a higher layer parameter sl-MultiReserveResource configured.
The device of any of claims 53 to 82, wherein the SL mode 2 resource selection or reselection procedure is at least triggered with a resource reservation interval parameter equal to zero or when the resource reservation interval parameter is not provided.
A device for candidate resource set initialization, used for a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

a processing unit, configured to initialize a candidate resource set according to a monitoring window for partial sensing.
The device of claim 85, wherein the processing unit configured to initialize the candidate resource set according to the monitoring window for partial sensing is configured to:

initialize the candidate resource set in such a manner that the candidate resource set allows a monitoring window for partial sensing with a minimum length, wherein the monitoring window for partial sensing is used for the Tx-UE to perform the partial sensing before a first slot of the candidate resource set and UE processing time.
The device of claim 85 or 86, wherein the partial sensing is contiguous partial sensing (CPS) and the monitoring window for partial sensing is a CPS monitoring window.
The device of claim 86 or 87, wherein a value of the minimum length is configured or preconfigured.
The device of claim 86 or 87, wherein a value of the minimum length is determined according to a L1 priority value.
The device of claim 89, wherein the L1 priority value is provided to the Tx-UE by a higher layer.
The device of claim 89, wherein a lower L1 priority value corresponds to a larger value of the minimum length.
The device of claim 86 or 87, wherein a value of the minimum length is determined according to remaining packet delay budget (PDB) or a percentage of remaining PDB.
The device of claim 92, wherein a larger remaining PDB corresponds to a larger value of the minimum length.
The device of claim 86 or 87, wherein a value of the minimum length is configured or preconfiguredfrom a range of values.
The device of any of claims 85 to 94, wherein the processing unit is further configured to:

determine the monitoring window as [n+T _A, n+T _B] , wherein n represents a triggering time slot where resource selection or reselection is triggered, T _Aand T _Bare values determined by the Tx-UE.
The device of claim 95, wherein

n + T _B = t _y0 –T _proc, 0 –T _proc, 1, wherein

t _y0 represents a first slot in a set of Y candidate slots, wherein Y is an integer and Y≥1;

T _proc, 0 represents a processing time for monitoring physical sidelink control channel (PSCCH) by the Tx-UE; and

T _proc, 1 represents a processing time for preparation of PSCCH/physical sidelink shared channel (PSSCH) transmission by the Tx-UE.
The device of claim 95 or 96, wherein T _A ≥ 1.
The device of any of claims 95 to 97, wherein M ≤T _B–T _A ≤31, M represents the minimum length of the monitoring window for partial sensing.
A device for candidate resource set initialization, used for a transmitter user equipment (Tx-UE) in a sidelink (SL) mode 2 resource selection or reselection procedure and comprising:

a processing unit, configured to initialize a candidate resource set according to a set of Y candidate slots, wherein Y is an integer and Y ≥ 1.
The device of claim 99, wherein the processing unit configured to initialize the candidate resource set according to the set of Y candidate slots is configured to:

initialize the candidate resource set in such a manner that the candidate resource set overlaps at least a minimum number of slots in the set of Y candidate slots that are located within a resource selection window.
The device of claim 100, wherein the minimum number is configured or preconfigured.
The device of claim 100, wherein the set of Y candidate slots at least comprises the minimum number of slots.
The device of any of claims 99 to 102, wherein the set of Y candidate slots are selected in periodic-based partial sensing (PBPS) .
The device of claim 103, wherein the set of Y candidate slots are selected to overlap at least N slots of SL-discontinuous reception (DRX) active time of a receiver user equipment (Rx-UE) , wherein N is an integer and N ≥ 1, and the SL-DRX active time of the Rx-UE is provided to the Tx-UE by a higher layer.
A user equipment (UE) comprising:

a processor; and

a memory configured to store a computer program;

the processor being configured to invoke and run the computer program stored in the memory to perform the method of any of claims 1 to 32.
A user equipment (UE) comprising:

a processor; and

a memory configured to store a computer program;

the processor being configured to invoke and run the computer program stored in the memory to perform the method of any of claims 33 to 46.
A user equipment (UE) comprising:

a processor; and

a memory configured to store a computer program;

the processor being configured to invoke and run the computer program stored in the memory to perform the method of any of claims 47 to 52.
A chip comprising:

a processor, configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of any of claims 1 to 32.
A chip comprising:

a processor, configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of any of claims 33 to 46.
A chip comprising:

a processor, configured to invoke and execute a computer program in a memory, to cause a device equipped with the chip to perform the method of any of claims 47 to 52.
A computer-readable storage medium storing computer programs which are operable with a computer to performthe method of any of claims 1 to 32.
A computer-readable storage medium storing computer programs which are operable with a computer to perform the method of any of claims 33 to 46.
A computer-readable storage medium storing computer programs which are operable with a computer to perform the method of any of claims 47 to 52.
A computer program product comprising computer program instructions which are operable with a computer to perform the method of any of claims 1 to 32.
A computer program product comprising computer program instructions which are operable with a computer to perform the method of any of claims 33 to 46.
A computer program product comprising computer program instructions which are operable with a computer to perform the method of any of claims 47 to 52.
A computer program being operable with a computer to perform the method of any of claims 1 to 32.
A computer program being operable with a computer to perform the method of any of claims 33 to 46.
A computer program being operable with a computer to perform the method of any of claims 47 to 52.