Method and device for sidelink communication

Abstract

To provide a method and a device for sidelink communication that contribute to improving channel access efficiency of a PSFCH on a shared spectrum.SOLUTION: A method includes the following: that is, a terminal device receiving a first PSSCH; the terminal device performing channel access on a shared spectrum; the first PSSCH being associated with a plurality of PSFCH transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being determined based on reserved resources and / or dynamic resources on the shared spectrum; the terminal device transmitting a first PSFCH using one PSFCH transmission resource of the plurality of PSFCH transmission resources; and the first PSFCH carrying feedback information related to the first PSSCH.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to the field of communication technologies, and in particular to methods and devices for sidelink communication. [Background technology]

[0002] When performing sidelink communication over a shared spectrum, a terminal device performs a channel access process through a mechanism such as listen before talk (LBT). If the terminal device transmits a physical sidelink feedback channel (PSFCH), and the channel access process fails, the transmission of the feedback information carried by the PSFCH may fail. Summary of the Invention [Problem to be solved by the invention]

[0003] For a terminal device that receives a PSFCH, even if the feedback information is an acknowledgement (ACK), the terminal device cannot receive the feedback information, so the overhead for retransmission occurs, which affects the transmission efficiency of the system. Therefore, how to improve the channel access efficiency of the PSFCH is an urgent problem to be solved. [Means for solving the problem]

[0004] The present disclosure provides a method and device for sidelink communication that contributes to improving channel access efficiency of the PSFCH.

[0005] Some embodiments of the present disclosure provide a method for sidelink communication, the method including: a terminal device receiving a first physical sidelink shared channel (PSSCH); the terminal device performing channel access on a shared spectrum; the first PSSCH being associated with multiple PSFCH transmission resources on the shared spectrum; the multiple PSFCH transmission resources being determined based on reserved resources, dynamic resources, or reserved and dynamic resources on the shared spectrum; the terminal device transmitting the first PSFCH through one PSFCH transmission resource of the multiple PSFCH transmission resources; and the first PSFCH carrying feedback information related to the first PSFCH.

[0006] Some embodiments of the present disclosure provide a method for sidelink communication, the method including: a terminal device performing channel listening on a shared spectrum; and, in response to a result of the channel listening being an idle channel, transmitting a first sidelink channel by consecutive-slot transmission, the consecutive-slot transmission corresponding to a plurality of consecutive time slots, a first transmission block carried by the first sidelink channel including transmission data corresponding to the plurality of consecutive time slots, the first sidelink channel including at least one PSFCH.

[0007] Some embodiments of the present disclosure provide a device for sidelink communication, where the device is a terminal device, including: a receiving unit configured to receive a first PSFCH; an access unit configured to perform channel access on a shared spectrum, where the first PSSCH is associated with a plurality of PSFCH transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being determined based on reserved resources, dynamic resources, or reserved and dynamic resources on the shared spectrum; and a transmitting unit configured to transmit the first PSFCH through one PSFCH transmission resource of the plurality of PSFCH transmission resources, where the first PSFCH carries feedback information related to the first PSFCH.

[0008] Some embodiments of the present disclosure provide a device for sidelink communications, where the device is a terminal device. The terminal device includes: a listening unit configured to perform channel listening on a shared spectrum; and a transmitting unit configured to transmit a first sidelink channel by consecutive slot transmissions in response to a result of the channel listening indicating an idle channel. The consecutive slot transmissions correspond to a plurality of consecutive time slots, and a first transmission block carried by the first sidelink channel includes transmission data corresponding to the plurality of consecutive time slots, and the first sidelink channel includes at least one PSFCH.

[0009] Some embodiments of the present disclosure provide a communication device including a memory and a processor, the memory configured to store a program that, when called and executed by the processor, causes the processor to perform the operations of the methods set forth above.

[0010] Some embodiments of the present disclosure provide a device including a processor configured to invoke and execute a program stored in a memory to perform the operations of the methods set forth above.

[0011] Some embodiments of the present disclosure provide a chip including a processor configured to invoke and execute a program stored in a memory to cause a device including the chip to perform the operations of the methods set forth above.

[0012] Some embodiments of the present disclosure provide a non-transitory computer-readable storage medium configured to store a program that, when invoked and executed, causes a computer to perform the operations of the methods set forth above.

[0013] Some embodiments of the present disclosure provide a computer program product including a program that, when invoked and executed, causes a computer to perform the operations of the methods set forth above.

[0014] Some embodiments of the present disclosure provide a computer program, which when invoked and executed, causes a computer to perform the operations of the methods set forth above.

[0015] In an embodiment of the present disclosure, a PSSCH is associated with multiple PSFCH transmission resources, and a terminal device can use one of the multiple PSFCH transmission resources to transmit a PSFCH associated with the PSSCH. Therefore, even if the channel access process of the current transmission resource fails, the terminal device can select another PSFCH transmission resource to transmit the PSFCH. In this way, the channel access efficiency of the PSFCH can be improved, which contributes to reducing overhead and improving transmission efficiency. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 illustrates a wireless communication system in accordance with some embodiments of the present disclosure. [Figure 2] FIG. 1 is a schematic diagram of NR-V2X communication. [Figure 3] FIG. 1 is a structural diagram of a frame that does not carry a PSFCH. [Figure 4] 1 is a structural diagram of a frame carrying a PSFCH. [Figure 5] 1 is a flow diagram of a method for sidelink communication according to some embodiments of the present disclosure. [Figure 6] 10 is a flow diagram of another method for sidelink communication according to some embodiments of the present disclosure. [Figure 7] 7 is a schematic diagram of a possible frame structure for multiple consecutive time slots in the method shown in FIG. 6. [Figure 8] FIG. 7 is a schematic diagram of another possible frame structure for multiple consecutive time slots in the method shown in FIG. 6. [Figure 9] FIG. 1 is a structural diagram of a device for sidelink communication according to some embodiments of the present disclosure. [Figure 10] FIG. 10 is a structural diagram of another device for sidelink communication in accordance with some embodiments of the present disclosure. [Figure 11] FIG. 1 is a structural diagram of a communication device according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0017] The following describes the technical solutions of the present disclosure in conjunction with the accompanying drawings. For ease of understanding, the following first introduces the terms and communication processes involved in the present disclosure in conjunction with Figures 1 to 4.

[0018] 1 is a diagram of an organizational architecture of a wireless communication system 100 in accordance with some embodiments of the present disclosure. The wireless communication system 100 may include a network device 110 and terminal devices 121 through 129. The network device 110 may provide communication coverage to a particular geographic area and can communicate with terminals within the coverage area.

[0019] In some implementations, communication between terminal devices may be performed over a sidelink (SL), which may also be referred to as proximity service (ProSe) communication, one-sided communication, sidelink communication, device-to-device (D2D) communication, and sidelink communication.

[0020] In other words, sidelink data is transmitted between terminal devices over a sidelink. The sidelink data may include data and / or control signaling. In some implementations, the sidelink data may be, for example, a Physical Sidelink Control Channel (PSCCH), a PSSCH, a PSCCH Demodulation Reference Signal (DMRS), a PSSCH DMRS, a PSFCH, etc.

[0021] Below, some common sidelink communication scenarios are described in relation to Figure 1. There are three scenarios for sidelink communication, depending on whether the terminal device using the sidelink is within the coverage area of ​​the network device: Scenario 1: The terminal device performs sidelink communication within the coverage area of ​​the network device. Scenario 2: Some terminal devices perform sidelink communication within the coverage area of ​​the network device. Scenario 3: The terminal device performs sidelink communication outside the coverage area of ​​the network device.

[0022] 1 , in scenario 1, terminal devices 121 to 122 communicate over a sidelink, and terminal devices 121 to 122 are within the coverage area of ​​network device 110. In other words, terminal devices 121 to 122 are within the coverage area of ​​the same network device 110. In this scenario, network device 110 may send configuration signaling to terminal devices 121 to 122, and in response, terminal devices 121 to 122 communicate over a sidelink based on the configuration signaling.

[0023] 1 , in scenario 2, terminal devices 123 and 124 communicate over the sidelink, and terminal device 123 is within the coverage area of ​​network device 110, while terminal device 124 is outside the coverage area of ​​network device 110. In this case, terminal device 123 receives configuration information from network device 110 and communicates over the sidelink based on the configuration signaling. However, for terminal device 124 outside the coverage area of ​​network device 110, terminal device 124 cannot receive configuration information from network device 110. In this case, terminal device 124 may acquire a configuration for sidelink communication according to preconfigured configuration information and / or configuration information sent by terminal device 123 within its coverage area, and communicate with terminal device 123 over the sidelink based on the acquired configuration.

[0024] In some implementations, the terminal device 123 may transmit the above-mentioned configuration information to the terminal device 124 over a physical sidelink broadcast channel (PSBCH) to configure the terminal device 124 to communicate over the sidelink.

[0025] 1, in scenario 3, terminal devices 125 to 129 are all outside the coverage area of ​​network device 110 and cannot communicate with network device 110. In this case, the terminal devices perform sidelink communication based on preconfigured information.

[0026] 1 illustrates a network device and multiple terminal devices by way of example. Alternatively, the wireless communication system 100 may include multiple network devices, and the coverage area of ​​each network device may include other numbers of terminal devices. The embodiments of the present disclosure are not particularly limited thereto.

[0027] In some implementations, the wireless communication system 100 may further include other network entities such as a network controller, a mobility management entity, etc. The embodiments of the present disclosure are not particularly limited thereto.

[0028] It should be understood that the technical solutions of the embodiments of the present disclosure may be applied to various communication systems, such as a fifth generation (5G) system or a new radio (NR) system, a long term evolution (LTE) system, an LTE frequency division duplex (FDD) system, an LTE time division duplex (TDD) system, etc. The technical solutions provided by the present disclosure may also be applied to future communication systems, such as a sixth generation mobile communication system, a satellite communication system, etc.

[0029] A terminal device in an embodiment of the present disclosure may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile radio station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, wireless communication device, user proxy, or user device. A terminal device in an embodiment of the present disclosure may refer to a device that provides voice and / or data connectivity to a user and may be used to connect people, things, and machines, such as a handheld device with wireless connectivity or an in-vehicle device. A terminal device in an embodiment of the present disclosure may be a mobile phone, a tablet PC, a laptop, a personal digital assistant, a mobile internet device (MID), a wearable device, a vehicle, a wireless terminal in industrial control, a wireless terminal in autonomous driving, a wireless terminal in remote medical surgery, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, or the like. Alternatively, a terminal device may be used as a base station. For example, a terminal device may act as a scheduling entity providing sidelink signals between terminal devices in vehicle-to-everything (V2X) or D2D, etc. For example, cellular phones and vehicles communicate with each other using sidelink data, and cellular phones and smart home devices communicate with each other without the need for relayed communication signals by a base station.

[0030] A network device of an embodiment of the present disclosure may be a device configured to communicate with a terminal device, and the network device may also be referred to as an access network device or a wireless access network device, such as a base station. A network device of an embodiment of the present disclosure may refer to a Radio Access Network (RAN) node (or device) that connects a terminal device to a wireless network. The term "base station" broadly encompasses various names below or may be substituted with names such as NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, transmitting and receiving point (TRP), transmitting point (TP), access point (AP), main station MeNB, secondary station SeNB, multi-standard wireless (MSR) node, home base station, network controller, access node, wireless node, transmitting node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. A base station may be a macro base station, a micro base station, a relay node, a donor node, etc., or a combination thereof. A base station may also refer to a communication module, a modem, or a chip installed in any of the aforementioned equipment or devices. A base station may be a mobile switching center or a device that acts as a base station in D2D, V2X, or machine-to-machine (M2M) communications, a network end device in 6G networks, and a device that acts as a base station in future communication systems.The base stations may support networks using the same or different access technologies. The embodiments of the present disclosure do not limit the network devices to a particular technology or device configuration.

[0031] A base station may be fixed or mobile. For example, a helicopter or drone may be configured to act as a mobile base station, and one or more cells may move depending on the location of the mobile base station. In other examples, a helicopter or drone may be configured as a device for communicating with another base station.

[0032] In some deployments, the network device of the present disclosure may refer to a CU or a DU, or the network device may include a CU and a DU. The gNB may also include an AAU.

[0033] The network devices and terminal devices may be deployed indoors or outdoors, handheld or vehicle-mounted, on land, on water, or on airborne aircraft, balloons, and satellites. The embodiments of the present disclosure do not limit the scenarios in which the network devices and terminal devices are deployed.

[0034] It should be understood that all or part of the functionality of the communication device of the present disclosure may also be realized through software functions running on hardware or through virtualization functions instantiated on a platform such as a cloud platform.

[0035] Sidelink Communication Mode With the development of sidelink communication technology, sidelink communication technology includes information exchange between various terminal devices. Taking the V2X communication system 200 shown in Figure 2 as an example, vehicle-to-vehicle (V2V) communication between terminal device 201 and terminal device 202 includes information exchange between vehicles. Vehicle-to-infrastructure (V2I) communication, vehicle-to-network (V2N) communication, and vehicle-to-pedestrian (V2P) communication between terminal device 201 and terminal devices 203 to 205 include information exchange between vehicles and external systems.

[0036] The gradual expansion of the scope of information exchange has put forward higher requirements for communication systems. Take the development of V2X as an example: in LTE-V2X, only the broadcast mode is supported for sidelink communication between terminal devices. In NR-V2X, three communication modes can be supported: broadcast, groupcast, and unicast.

[0037] Broadcast is the most basic communication mode for sidelink communication. In the broadcast transmission mode, the terminal device receiving the sidelink data may be any terminal device around the terminal device acting as a transmitter. For example, referring to FIG. 1 , if the terminal device 125 is a transmitter and transmits sidelink data by broadcast, any of the terminal devices 121 to 124 and 126 to 129 around the terminal device 125 may act as a receiver of the sidelink data.

[0038] Groupcast communication is used to support information exchange between terminal devices in a particular group (or communication group) to aid in negotiation and decision-making among the terminal devices in the group. A communication group using groupcast communication may be a managed group with stable connections, or a temporary group configured in a connectionless manner.

[0039] In a groupcast transmission, the terminal devices receiving the sidelink data may be all terminal devices in the communication group. Alternatively, the terminal devices receiving the sidelink data may be all terminal devices within a certain transmission range. For example, referring to FIG. 1 , for a communication group including terminal devices 127 to 129, when terminal device 127 transmits sidelink data in a groupcast manner, the other terminal devices 128 to 129 in the communication group are the receiving terminals receiving the sidelink data. For example, referring to FIG. 1 , assuming that the terminal devices within a predetermined range include terminal devices 127 to 129, when terminal device 127 transmits sidelink data in a groupcast manner, the other terminal devices 128 to 129 within the predetermined range are the receiving terminals receiving the sidelink data.

[0040] Unicast communication can realize sidelink communication between two terminal devices. Taking NR-V2X as an example, wireless resource control (RRC) signaling based on the PC5 interface can realize reliable communication from one terminal device to another.

[0041] In the unicast transmission mode, there is usually only one terminal device receiving the sidelink data. As shown in FIG. 1, communication between the terminal device 121 and the terminal device 122 may be performed by unicast communication. For example, when the terminal device 121 communicates with the terminal device 122 using the sidelink, the terminal device 122 receives the sidelink data as the only receiving device. The sidelink data includes the PSSCH and the PSCCH. The terminal device 122 may obtain sidelink control information (SCI) related to the sidelink transmission and scheduling by demodulation, and the SCI may help the terminal device 122 receive and decode the sidelink information.

[0042] In some communication systems, the sidelink supports a hybrid automatic repeat request (HARQ) mechanism with ACK / Negative Acknowledgement (NACK). Sidelink HARQ feedback is transmitted by the receiving terminal device to the transmitting terminal device on the PSFCH.

[0043] In sidelink communication, the terminal device may be a device that meets the provisions of different protocols and includes an LTE SL module and / or an NR SL module. The different protocols may be protocols released or planned to be released under the 3rd Generation Partnership Project (3GPP), including Rel-16, Rel-17, Rel-18, etc. In particular, these terminal devices mainly include the following five types:

[0044] Class A Device: Rel-18 devices including LTE SL and NR SL modules.

[0045] Class B Device: A Rel-18 device that contains only NR SL modules.

[0046] Class C Device: Rel-14 / Rel-15 device that contains only an LTE SL module.

[0047] Class D Device: Rel-16 / Rel-17 device that contains only NR SL modules.

[0048] Class E Devices: Rel-16 devices including LTE SL and NR SL modules.

[0049] Sidelink resource allocation method In some communication systems (such as NR), two resource allocation methods for sidelink resources are defined, including Mode 1 and Mode 2.

[0050] In mode 1, the network device schedules sidelink resources for the terminal device.

[0051] Currently, Mode 1 includes two methods: dynamic resource configuration and sidelink configuration authorization. For dynamic resource configuration, a network device may allocate sidelink transmission resources to a terminal device by transmitting downlink control information (DCI). The DCI corresponds to the physical downlink control channel (PDCCH). For sidelink configuration authorization, when a terminal device is configured with sidelink resources and has data to be transmitted, the terminal device may transmit the data using the configured sidelink resources without having to re-apply for sidelink resources from the network device. For periodic services, a network device typically allocates semi-static transmission resources to a terminal device. By scheduling transmission resources for a terminal device on a direct link by the network device, resource contention can be effectively prevented and the hidden node problem can be addressed.

[0052] For example, referring to FIG. 1, terminal devices 121 to 123 are within the coverage area of ​​network device 110, and network device 110 may allocate sidelink resources for terminal devices 121 to 123.

[0053] In Mode 2, the terminal device independently selects sidelink resources from the sidelink resource pool.

[0054] The sidelink resource pool may be configured by the network device or may be pre-configured. In some embodiments, the network device may configure the sidelink resource pool for the terminal device through high-level signaling. The terminal device selects time-frequency resources from the resource pool configured or pre-configured by the network device by listening to or randomly selecting resources. For example, if the terminal devices 124 to 129 in FIG. 1 are outside the coverage area of ​​the network device 110, the terminal devices 124 to 129 may independently select sidelink resources from the resource pool configured by the network device.

[0055] In this mode, the terminal device may reserve resources for blind transmission (or blind retransmission) of a transport block (TB) or transmission (or retransmission) based on HARQ feedback based on scheduling instructions or resource awareness from the SCI. For example, SCI-1 transmitted by the terminal device on the PSCCH indicates the time-frequency resources reserved by the terminal device, and the aware terminal device excludes the resources indicated in the SCI, thereby reducing the probability of resource contention.

[0056] The processes executed by the terminal device include a resource awareness process and / or a resource selection process. A terminal device within an awareness window may recognize resources within a selection window, thereby selecting or excluding candidate resources within the selection window. The end point of the resource selection window is before the trigger point of resource selection. During the awareness process, the terminal device may also determine the occupancy or interference of sidelink resources by measuring the values ​​of Reference Signal Received Power (RSRP) of the resources within the awareness window.

[0057] For periodic services, the sidelink may reserve (or set aside) sidelink communication resources for the terminal device at the expected arrival time of the data to prevent resource contention with other terminal devices. For example, the transmission resources (transmission timing) of the PSFCH may appear periodically in the time domain within the resource pool and have a configured / preconfigured periodicity.

[0058] Side link system frame structure The frame structure (time slot structure) of a system frame for sidelink according to an embodiment of the present disclosure is shown below in connection with Figures 3 and 4. The system frame is a single time slot containing 14 time domain symbols. The system frame includes two structures: with feedback and without feedback. Feedback is carried by the PSFCH as shown above. Figure 3 shows the frame structure of a system frame that does not carry a PSFCH, and Figure 4 shows the frame structure of a system frame that carries a PSFCH.

[0059] The SCI in Figures 3 and 4 includes two parts: a first-stage SCI (SCI-1) and a second-stage SCI (SCI-2). The first-stage SCI-1 is transmitted on the PSCCH, and the second-stage SCI-2 is transmitted on the PSSCH.

[0060] 3, in the time domain, the sidelink symbols occupied by SCI-1 transmitted on the PSCCH start from the second sidelink symbol (e.g., an Orthogonal Frequency Division Multiplexing (OFDM) symbol) of the system frame and include two or three sidelink symbols. Transmitting the PSCCH at the beginning of a time slot facilitates the receiving terminal device to start demodulating the PSCCH as early as possible, and earlier acquisition of the PSCCH by the terminal device may reduce the power consumption of the terminal device.

[0061] In the frequency domain, the PSCCH may occupy multiple physical resource blocks (PRBs). Generally, to reduce the complexity of blind detection of the PSCCH by a terminal device, the number of PSCCH symbols and the number of PRBs in a resource pool are configured as fixed values, respectively.

[0062] Referring to Figure 3, in the time domain, SCI-2 transmitted on the PSSCH also starts from the second sidelink symbol of the system frame and ends at the penultimate sidelink symbol of the system frame. In the frequency domain, the PSSCH occupies multiple subchannels for the system frame. In the sidelink resource pool, a subchannel is the smallest granularity for allocating frequency domain resources for the PSSCH. The resource pool is made up of n subchannels, each of which has SubCHsize may include multiple sub-channels consisting of n PRBs, and in this specification, SubCHsize has the values ​​10, 12, 15, 20, 25, 50, 75, or 100.

[0063] Thus, the PSCCH and the portion of the PSSCH with which the PSCCH is associated are transmitted on resources that overlap in time but do not overlap in frequency, and other portions of the PSCCH and PSSCH are transmitted on resources that do not overlap in time.

[0064] Typically, the first sidelink symbol in a timeslot is a repeat of the second sidelink symbol. When a terminal device receives a system frame, the first sidelink symbol may be used as an automatic gain control (AGC) symbol. The data in the AGC symbol is usually not used for data demodulation. The last symbol of the timeslot is a GAP symbol, which serves as a protection gap.

[0065] Referring to Figure 4, when the PSFCH is carried in a timeslot, the penultimate and third penultimate sidelink symbols of the system frame are used for PSFCH transmission. Furthermore, a GAP symbol should be reserved after the PSSCH or PSFCH. The value of the pre-configured cycle of PSFCH resources may be {1, 2, 4} timeslots.

[0066] The SCI configuration can support multiplexing scheduling for multiple services in a single timeslot.

[0067] Sidelink communication spectrum The spectrum used by communication systems includes licensed spectrum and unlicensed spectrum. An important aspect of the expansion of communication systems into different areas is the use of unlicensed spectrum. For example, NR deployed on unlicensed spectrum is called NR-U.

[0068] Currently, sidelink mainly uses licensed spectrum. Sidelink may also use unlicensed spectrum. Sidelink deployed on unlicensed spectrum is sometimes referred to as SL-U.

[0069] Compared to licensed spectrum, unlicensed spectrum has the characteristic of being shared without permission, and therefore unlicensed spectrum is also known as shared spectrum. For operators, spectrum sharing facilitates the aggregation of spectrum when appropriate to dynamically support high-bandwidth services. Spectrum sharing can also extend the benefits of communications technologies (such as NR) to operators that may not be able to obtain licensed spectrum.

[0070] Spectrum sharing requires consideration of the coexistence of different radio access technology (RAT) systems, such as Wireless Fidelity (WiFi) systems and LTE-based licensed assisted access (LAA) systems. Different systems compete to use frequency bands in the unlicensed spectrum based on the principles of channel access fairness and multi-RAT coexistence.

[0071] In a shared spectrum, any RAT system must communicate within the limits of unlicensed spectrum supervisory rules, which include power and power spectral density levels, maximum channel occupancy time (COT), bandwidth occupied by a channel, channel listening mechanisms, etc. In the same frequency band, each system must reasonably occupy and release channels to meet the requirements of the supervisory rules and prevent interference with other RAT systems in the same frequency band.

[0072] With regard to the use of shared spectrum, RAT systems may use mandated channel listening techniques (such as LBT) to access the network. That is, data transmission occurs only when the current channel is heard to be unoccupied. Therefore, some data cannot be guaranteed to be transmitted on a predetermined channel.

[0073] When performing sidelink communication over a shared spectrum, a terminal device may detect the presence of an idle channel using a channel listening mechanism such as LBT, and then perform channel access on the idle resource and transmit data based on the above supervision rules. For example, when a terminal device transmits data on a channel resource, the COT restriction should be satisfied. That is, continuous data transmission should be limited to the COT time, and if it is exceeded, the terminal device should release the channel and perform LBT again.

[0074] When sharing a spectrum to perform channel access, in response to a failure of the channel access process (eg, an LBT failure), the transmission of the terminal device may be interrupted.

[0075] For highly important transmissions, a failure in the channel access process may lead to the loss of important transmission information. An example of a highly important transmission is the transmission of the PSFCH. The PSFCH is used to carry HARQ feedback for the PSSCH. The lack of HARQ feedback may significantly impact performance. Therefore, in resource allocation mode 2, for the PSFCH, Type 1 LBT is generally used as the baseline channel access, with a channel access priority class (CAPC) value p=1. A value of p of 1 indicates that the PSFCH has a relatively high channel access priority class. Subject to all applicable restrictions, the PSFCH may also use Type 2 LBT for channel access in the case of COT sharing.

[0076] As described above, transmission opportunities (TOs) for the PSFCH may occur periodically in the time domain within a resource pool. The transmission opportunities for the PSFCH may be one or more RBs within a set of available resource blocks (RBs). The PSSCH is transmitted using subchannels in the resource pool and time slots in the time domain. PSFCH transmission may be implemented by mapping PSSCH transmission resources to one or more RBs. In the associated sidelink, the timeline for the PSFCH to provide HARQ feedback has only one opportunity for PSFCH transmission. That is, the PSSCH transmission is associated with only a single transmission opportunity for the PSFCH. Therefore, before a terminal device transmits feedback corresponding to the PSSCH, a channel access process should be performed before the PSFCH transmission opportunity associated with the PSSCH.

[0077] As mentioned above, there are uncertainties in channel access mechanisms such as LBT. When the channel access process of the PSFCH performed before the transmission opportunity fails, the HARQ feedback related to the PSSCH (such as the HARQ-ACK feedback) cannot be transmitted and is discarded. The lack of HARQ feedback from the PSSCH can have a significant impact on performance.

[0078] Taking a unicast link as an example, a terminal device acting as a transmitter transmits a PSSCH, and a terminal device acting as a receiver receives and provides feedback on the reception status. When the LBT performed by the receiving terminal device before transmitting the PSFCH fails, the transmitting terminal device regards the lost PSFCH signal as a NACK. That is, when the feedback carried by the PSFCH is a HARQ-NACK, the transmitting terminal device retransmits the PSSCH regardless of whether the PSSCH is lost or not. When the feedback carried by the PSFCH is an ACK, the transmitting terminal device must also retransmit the PSSCH due to not receiving feedback information. Retransmitting the PSSCH brings about certain overhead, thereby affecting transmission performance and transmission efficiency. Furthermore, for a receiving terminal device, after receiving the PSSCH, the terminal device first decodes it and provides feedback based on the decoding result. When the feedback information is discarded, decoding by the terminal device becomes unnecessary overhead, thereby further affecting system performance and transmission efficiency.

[0079] Therefore, due to the uncertainty of channel access on the shared spectrum, when a PSSCH transmission is associated with only one PSFCH transmission opportunity, the channel access efficiency for the PSFCH is low, thereby further affecting the system performance and transmission efficiency.

[0080] In view of this, some embodiments of the present disclosure provide a method for sidelink communication. In the method, a PSFCH is associated with multiple PSFCH transmission resources, and a terminal device can flexibly select one PSFCH transmission resource from the multiple PSFCH transmission resources to transmit the PSFCH. In this way, the reliability of channel access for the PSFCH can be increased. A method for sidelink communication according to some embodiments of the present disclosure is illustrated below in connection with FIG. 5.

[0081] Referring to FIG. 5, at S510, the terminal device receives a first PSSCH.

[0082] The terminal device may be a device for sidelink communications. For example, the terminal device may be a Class A device, a Class B device, or one of the other three types of devices listed above. In some embodiments, the terminal device may function as a sidelink receiver to receive data transmitted by other terminal devices. In some embodiments, the terminal device may function as a sidelink transmitter to transmit data and feedback information to other terminal devices.

[0083] The terminal device may receive the first PSSCH using multiple communication modes. In some embodiments, the terminal device may be a receiving device for unicast communication. In some embodiments, the terminal device may be a group member of a broadcast communication group or communication group and receive the first PSSCH transmitted by a group header terminal or other group members. For example, the terminal device may be a vehicle receiving the first PSSCH transmitted by other vehicles in the communication group.

[0084] In some embodiments, the terminal device receiving the first PSSCH may be within or outside the coverage area of ​​the network. For example, a terminal device within the coverage area of ​​the network may receive the first PSSCH transmitted by the network device.

[0085] The first PSSCH may be a sidelink that includes SCI-2. The terminal device may demodulate the first PSSCH based on SCI-2 to receive transmission data carried by the first PSSCH, such as a transmission block.

[0086] The first PSSCH transmission may be a transmission based on consecutive RBs, interleaved RBs, or interlaced RBs. In some embodiments, with respect to PSSCH transmission, one subchannel may be considered as a interlaces, where a may be given the value 1 or other fixed value herein. In some embodiments, the subchannel used to transmit the PSSCH may be restricted to one RB set or may be included in one or more RB sets in a resource pool.

[0087] The first PSSCH may be a data channel with a particular HARQ timeline or a data channel with a different HARQ timeline.

[0088] At S520, the terminal device performs channel access on the shared spectrum.

[0089] Channel access may be an initial access for data transmission by a terminal device. In some embodiments, channel access may include only an initial access performed by the terminal device. For example, channel access may be resource awareness access. In some embodiments, channel access may include channel listening and initial access performed by the terminal device.

[0090] On the shared spectrum, the first PSFCH of S510 may be associated with multiple PSFCH transmission resources. A PSFCH transmission resource may be one or more RBs. In the time domain, a PSFCH transmission resource may also be referred to as a PSFCH transmission opportunity.

[0091] In some embodiments, the requirements of different transmission modes regarding PSFCH transmission resources may be met by mapping a first PSFCH to multiple PSFCH transmission resources. For example, for consecutive slot transmission, some time slots of the system frame structure may not be used for transmitting the PSFCH. Flexible mapping to PSFCH transmission resources may improve transmission efficiency.

[0092] The multiple PSFCH transmission resources may be contiguous or discontinuous time-frequency resources. In some embodiments, the multiple PSFCH transmission resources may be multiple consecutive RBs in a resource pool. In some embodiments, the multiple PSFCH transmission resources may be allocated in an interleaved and interlaced manner. An interleaved waveform may be associated with the number of RBs required for each PSFCH. In some embodiments, each PSFCH transmission resource may appear on consecutive resources of the same time slot.

[0093] The multiple PSFCH transmission resources may be determined based on multiple types of resources, which are described in detail below.

[0094] The number of PSFCH transmission resources may be indicated by the SCI or other dedicated signaling. In some embodiments, the SCI may indicate the timeslot length (number of timeslots) of the number of PSFCH transmission resources. In some embodiments, the number of PSFCH transmission resources may be indicated by the SCI configuration signaling or other dedicated signaling.

[0095] At S530, the terminal device transmits a first PSFCH using one PSFCH transmission resource of the plurality of PSFCH transmission resources.

[0096] The first PSFCH may carry feedback information related to the first PSSCH, and the feedback information may be an ACK or NACK of the HARQ feedback.

[0097] In some embodiments, the feedback information may be determined based on reception of the first PSSCH by the terminal device. For example, in a severe transmission environment, the first PSSCH received by the terminal device suffers from packet loss, and the feedback information is a NACK. In some embodiments, the feedback information may be determined based on decoding of the first PSSCH by the terminal device. For example, after decoding the first PSSCH, the terminal device determines that transmission of the first PSSCH is successful, and the feedback information is an ACK.

[0098] The first PSFCH transmission may be either an initial transmission of the feedback information or a retransmission of the feedback information.

[0099] The first PSFCH may be transmitted over time-frequency resources of multiple PSFCH transmission resources. In some embodiments, the first PSFCH may be transmitted over one PSFCH transmission resource. In some embodiments, the first PSFCH may be transmitted over multiple PSFCH transmission resources. For example, when the first PSFCH is associated with t transmission resources, the first PSFCH may be transmitted over less than t transmission resources or t transmission resources. The PSFCH transmission resources may be interlaced and interleaved.

[0100] In some embodiments, the first PSFCH may be flexibly transmitted based on multiple PSFCH transmission resources. For example, the terminal device may select any one of the multiple PSFCH transmission resources according to a successful channel access process. For example, when the channel access process of a PSFCH before a transmission resource fails, the terminal device may select a later transmission resource for transmission. The later transmission resource may be occupied by the next cycle or the next channel to ensure the transmission of HARQ feedback.

[0101] According to FIG. 5, in a method for sidelink communication provided by an embodiment of the present disclosure, a PSSCH is associated with multiple PSFCH transmission resources. This flexible association method can improve channel access efficiency of the PSFCH. Furthermore, this flexible association method can serve as a compensation mechanism for failed channel access of the PSFCH. In this way, additional transmissions on more transmission resources can be allowed, thereby ensuring PSFCH transmission by terminal devices on a shared spectrum.

[0102] As described above, the multiple PSFCH transmission resources may be determined based on multiple types of resources.

[0103] In some embodiments, the multiple PSFCH transmission resources may be determined based on reserved resources on the shared spectrum. The reserved resources may provide multiple PSFCH transmission resources to guarantee the transmission requirements of the PSFCH. As an example, the reserved resources may be time-frequency resources in a resource pool configured by the network device for the terminal device or time-frequency resources in a pre-configured resource pool. As another example, the reserved resources may be time-frequency resources of the reserved resources determined by resource awareness and used for periodic transmission. As yet another example, the reserved resources may be time-frequency resources in COT sharing.

[0104] In some embodiments, the plurality of PSFCH transmission resources may be determined based on dynamic resources on a shared spectrum. The dynamic resources may be part of common resources reserved in a resource pool for dynamic scheduling. The dynamic resources may also be time-frequency resources not reserved or used in resource allocation mode 2.

[0105] When the reserved PSFCH transmission resources are fully occupied, the transmission resources may be determined by dynamic scheduling. For example, the dynamic scheduling may occupy other resources in a preconfigured resource pool for PSFCH transmission. Alternatively, the dynamic scheduling may schedule resources in other resource pools (non-preconfigured resource pools) for PSFCH transmission.

[0106] In some embodiments, the use of reserved or dynamic resources (common resources) may be determined based on the type of service. For example, different types of services may have different priorities. Services with higher priority may use reserved resources, and services with lower priority may use dynamic resources. Alternatively, services may be classified according to their quality of service (QoS) to determine which services use reserved resources and which services use dynamic resources. In other embodiments, the use of reserved or dynamic resources may be determined based on the arrival order and latency of the services. For example, a first-come, first-served allocation principle may be used.

[0107] In some embodiments, the terminal device may use the SCI to indicate a plurality of transmission resources of the reserved resources for transmitting the PSFCH. For example, the reserved resources may be associated with first indication information. The first indication information may be carried within the first SCI. For example, the first indication information may be carried within SCI-1 or SCI-2 of the first SCI.

[0108] In some embodiments, the first indication information may be determined based on one or more types of information.

[0109] In some embodiments, the first indication information may be determined based on the maximum number of resource blocks (RBs) required by each PSFCH transmission resource of the plurality of PSFCH transmission resources. The number of resource blocks may be determined by an equal division according to the total number of reserved resources, or by a specific division according to the requirements of the service. For example, the maximum number of RBs required by each PSFCH transmission resource may be k, where k is an integer equal to or greater than 1. When TO is used to represent each PSFCH transmission resource, the j-th TO of the plurality of TOs may be expressed as [RBs].j0 ,RB j0+k-1 ] may be expressed as

[0110] In some embodiments, the first indication information may be determined based on the number of first sidelink time domain units in the reserved resources. The first sidelink time domain unit may be a time slot. For example, when the reserved resources include a total of n time slots, the first indication information may indicate a number of PSFCH transmission resources based on the n time slots.

[0111] In some embodiments, the first indication information may be determined based on the number of resource blocks configured for PSFCH transmission in the first sidelink time domain unit. For example, when the first sidelink time domain unit is a timeslot, the number of resource blocks may be the total number of RBs in the timeslot of reserved resources.

[0112] In some embodiments, the first indication information may be determined based on the number of PSFCH transmission resources in the first sidelink time domain unit. For example, if the time slot is M S When there are M PSFCH transmission resources, the first indication information is S This may be used to indicate PSFCH transmission resources.

[0113] In some embodiments, the first indication information may be determined based on a service type corresponding to the first PSSCH. The service type may also be a service priority. For example, when the first PSSCH carries a real-time service with a relatively high priority, the first indication information may indicate that the first PSSCH is associated with a plurality of PSFCH transmission resources that are close in time to the first PSSCH. For example, when the first PSSCH carries a periodic service, the first indication information may configure a plurality of PSFCH transmission resources associated with the first PSSCH to be periodic.

[0114] In some embodiments, the first indication information may be determined based on two or more types of information shown above. The first indication information may indicate an index of each transmission resource. For example, the reserved resources include M PSFCH transmission resources, and the first indication information corresponding to the j-th PSFCH transmission resource among the M PSFCH transmission resources may be represented as IndexTO, where IndexTO may satisfy the following equation:

[0115]

number

[0116] where j is an integer ranging in value from 0 to M-1, n represents the number of first sidelink time domain units in the reserved resources, m represents the number of resource blocks configured for PSFCH transmission within the first sidelink time domain unit, and M S denotes the number of PSFCH transmission resources in the first sidelink time domain unit.

[0117] In some embodiments, reserving transmission resources for the PSFCH can meet the transmission requirements of the PSFCH in consecutive slot transmission. Depending on the SCI configuration or DCI scheduling, a large transmission block may be formed during the transmission of multiple consecutive time slots. Assuming that each time slot carries NACK / ACK, each transmission block requires multiple PSFCH transmission resources. That is, multiple HARQ codebooks exist in a transmission block, and transmitting a large number of transmission blocks per unit time requires a large amount of feedback. This significantly challenges the capabilities of terminal devices. Therefore, by reserving resources, the PSFCH corresponding to a PSSCH transmission may be mapped to a set of PSFCH resources. The reserved resources may be, for example, a set of all RBs within the same time slot, and the RBs may require interlaced transmission. By providing a dedicated set of PSFCH resources for consecutive slot transmission, the reserved resources can ensure that ACK / NACK feedback for each time slot of a complete transmission block has a PSFCH resource for transmission.

[0118] In some embodiments, after the terminal device performs channel access on the shared spectrum, the terminal device may first determine whether there is an idle PSFCH transmission resource among the reserved resources, for example, according to the first indication information.

[0119] For example, after successful access using LBT, if it is found that there are still reserved PSFCH transmission resources, the terminal device may select one of the PSFCH transmission resources to transmit the first PSFCH. When multiple PSFCH transmission resources are fully occupied, the terminal device may use dynamic resource allocation. That is, when there are no idle PSFCH transmission resources among the reserved resources, the terminal device may transmit the first PSFCH using dynamic resources as described above.

[0120] In some embodiments, the terminal device may determine whether to transmit the first PSFCH based on the feedback information. For example, the terminal device may set a first threshold (threshold value) for the number of NACK feedbacks. When the number of NACK feedbacks from the terminal device exceeds the first threshold, the terminal device may terminate transmission of the first PSFCH.

[0121] For example, the transmission of the first PSFCH may be terminated by adding an indication to disable HARQ to the SCI indication. Furthermore, an indication to disable / enable HARQ may be configured through the SCI. For example, whether HARQ is disabled for a service may be configured based on the QoS requirements of different services. For services requiring high QoS, HARQ may be enabled. For services requiring low QoS, HARQ may be disabled.

[0122] As another example, when a terminal device is in a harsh environment, NACKs are transmitted continuously. The terminal device needs to continuously perform LBT to transmit the PSFCH, which may cause resource contention with other terminal devices. Therefore, a maximum number of NACK transmissions may be set. When the number is exceeded, HARQ is disabled by the SCI in the next TB transmission.

[0123] In some embodiments, a terminal device performs channel listening before performing channel access on a shared spectrum. In a shared spectrum, a terminal device typically begins to perform resource selection and channel access only after successful channel listening. The terminal device may determine whether to transmit the first PSFCH using short control signaling transmission (SCSt) based on the result of channel listening. If the result of channel listening shows that the channel is always occupied, i.e., channel access continues to fail, the terminal device cannot transmit the PSFCH. In a possible implementation, the terminal device may set a second threshold for channel listening failure. For example, when the number of channel listening failures exceeds the second threshold, the terminal device may transmit the first PSFCH using SCSt.

[0124] Note that in shared spectrum, LBT is not required before SCSt. There are two restrictions on the use of SCSt: the number of short control signaling transmissions of a terminal device should be 50 or less within a 50 ms observation period, and the total duration of short control signaling transmissions of a terminal device during an observation period should be less than 2500 μs. If the short control signaling exceeds these two restrictions, channel access may be performed using LBT.

[0125] In some embodiments, the second threshold may be set based on the service, e.g., the second threshold for all services may be set to the same, e.g., the second threshold may be associated with the QoS of the service.

[0126] By reserving multiple PSFCH transmission resources, the channel access efficiency of the PSFCH can be improved, thereby compensating for the overhead and efficiency problems caused by the uncertain channel access of the PSFCH. Flexible mapping of PSFCH transmission resources can also meet the requirements of different transmission modes, such as consecutive slot transmission.

[0127] In consecutive slot transmission, in order to maximize the utilization rate of successful LBT attempts, a terminal device may use multiple consecutive time slots for transmitting large amounts of data. That is, multiple data (multiple transmission blocks) may be transmitted by a successful LBT. Therefore, using consecutive slot transmission for the same transmission data can prevent the LBT from being repeatedly performed for multiple independent time slots, thereby improving channel access efficiency. Multiple independent time slots may be multiple transmission blocks.

[0128] As described above, if each time slot of multiple consecutive time slots carries a NACK / ACK, the consecutive slot transmission requires a large amount of PSFCH transmission resources. In order to more effectively improve transmission efficiency, how to design a reasonable frame structure for PSFCH transmission using multiple consecutive time slots is also a problem to be solved.

[0129] To this end, some embodiments of the present disclosure provide another method for sidelink communication. In the method, a terminal device transmits a first sidelink channel by consecutive slot transmission, and one or more PSFCHs may be assigned to a transmission block carried by the first sidelink channel. Furthermore, PSFCH feedback may be flexibly transmitted in multiple time slots based on the PSFCH configuration, thereby improving transmission efficiency. The following is a detailed description of the method for sidelink communication in conjunction with FIG. 6. The method shown in FIG. 6 is related to FIG. 5. Therefore, for simplicity, FIG. 6 no longer provides a detailed description of terms already appearing in FIG. 5.

[0130] Referring to FIG. 6, at S610, the terminal device performs channel listening on the shared spectrum.

[0131] Channel listening may refer to a terminal device listening on multiple channel resources in a shared spectrum or a terminal device listening on a target channel resource.

[0132] The channel resource may be a resource in a shared spectrum or may be a COT resource shared by other terminal devices in a sidelink. For example, in V2X, a terminal device may perform channel listening on a COT share provided by a nearby vehicle.

[0133] In some embodiments, channel listening may refer to the terminal device performing listening on channel resources using an LBT mechanism, or the terminal device performing listening using channel awareness, etc. For example, the terminal device may determine the occupancy of sidelink resources based on the RSRP value of the sidelink DMRS.

[0134] The result of channel listening may be either that the listened-to channel resource is idle or that the listened-to channel is occupied. When the result of channel listening is that the channel is occupied, the channel listening is unsuccessful. The terminal device may continue to perform channel listening until an idle channel is found.

[0135] At S620, in response to the result of the channel listening being an idle channel, the terminal device transmits the first sidelink channel by consecutive slot transmission.

[0136] Consecutive slot transmission may be implemented by aggregating multiple time slots to improve transmission efficiency and reduce the LBT access process. A larger transmission block, i.e., a first transmission block, may be formed by aggregating multiple consecutive time slots.

[0137] The first transmission block may include transmission data corresponding to multiple consecutive time slots, and the size of the first transmission block may be relatively large compared to the transmission blocks corresponding to each transmission time slot, which may provide a relatively large coding gain.

[0138] Consecutive slot transmissions may be scheduled under different resource allocation modes. For example, in resource allocation mode 1, multiple consecutive time slots may be scheduled using the PDCCH, and multiple subsequent time slots, adjacent or non-adjacent to each other, may be scheduled using the PDCCH of the first time slot. For example, in resource allocation mode 2, multiple consecutive time slots may be scheduled using the SCI, and SCI-1 or SCI-2 parameters may be set in the first time slot and applied to subsequent time slots of the transmission.

[0139] The multiple consecutive time slots corresponding to consecutive slot transmission may be determined by multiple factors. For example, the formation of multiple time slots may be determined based on the same region / destination ID within the SCI. For example, the formation of multiple time slots may be determined based on adjacent time slots. For example, the formation of multiple time slots may be determined based on a groupcast or unicast transmission mode.

[0140] The first sidelink channel may include at least one of a PSCCH, a PSSCH, or a PSFCH. In consecutive slot transmission, the first sidelink channel may include one or more PSFCHs. For example, the SCI parameter may be set so that each timeslot has a PSFCH, or so that multiple consecutive timeslots have one PSFCH.

[0141] In some embodiments, the first sidelink channel may include one PSFCH, i.e., the first PSFCH. For multiple consecutive timeslots with one PSFCH, one or more symbols of the one timeslot may be selected to transmit the first PSFCH. For example, the last symbol of the last timeslot of the multiple consecutive timeslots may be defined as the first symbol, and the time domain resource for the first PSFCH may include one symbol adjacent to the first symbol. That is, the time domain resource for the first PSFCH may be the penultimate sidelink symbol of the last timeslot, or two consecutive symbols including the penultimate sidelink symbol.

[0142] In some embodiments, the first sidelink channel including one PSFCH may further include one SCI. The SCI may include SCI-1 and SCI-2, or may include SCI-1 or SCI-2. For example, the first sidelink channel may include one SCI-2, and the time domain resource including SCI-2 is in the first time slot of multiple consecutive time slots. Taking three consecutive time slots as an example, when the three time slots are time slot n, time slot n+1, and time slot n+2, the time domain resource including SCI-2 may include the first few symbols of time slot n excluding AGC, and time slots n+1 and n+2 are mainly used to transmit the PSSCH and PSFCH.

[0143] In some embodiments, the time domain resource including the SCI may correspond to the first time slot of multiple consecutive time slots. By setting the SCI in the first time slot, the parameters / fields of the SCI may be applied to all subsequent time slots during transmission. For example, SCI-2 of the first time slot may be used to demodulate the transmitted data of the first time slot and multiple subsequent time slots.

[0144] In some embodiments, when the first transmission block is configured using one PSFCH, the result of decoding by the terminal device may be determined to be NACK or ACK based on the first transmission block.

[0145] In some embodiments, the first sidelink channel may include multiple PSFCHs such that multiple PSFCH feedbacks are present in the first transmission block. The multiple PSFCHs may include a second PSFCH and at least one other PSFCH. The at least one other PSFCH may be one PSFCH or multiple PSFCHs. Thus, the multiple consecutive time slots may include the last time slot and at least one other time slot. The at least one other PSFCH may have a one-to-one correspondence with the at least one other time slot. Thus, the at least one other time slot may be one time slot or multiple time slots.

[0146] For multiple consecutive time slots configured with multiple PSFCHs, multiple symbols should be selected to transmit the multiple PSFCHs. In some embodiments, the symbols in multiple consecutive time slots are grouped, with the last symbol of the last time slot being referred to as the second symbol and the last symbol of at least one other time slot being referred to as the third symbol.

[0147] In some embodiments, the time domain resources for the second PSFCH may be the same as the first PSFCH described above and are not repeated here. The time domain resources for the at least one other PSFCH may include a third symbol. In other words, each time domain resource of the time domain resources for the at least one other PSFCH may be the last symbol of a respective time slot of the at least one other time slot. Again, taking three consecutive time slots as an example, three PSFCHs may be configured in a one-to-one correspondence with the three time slots. These three PSFCHs may include one second PSFCH and two other PSFCHs. When these three time slots are time slot n, time slot n+1, and time slot n+2, the second PSFCH may be configured in the penultimate symbol of time slot n+2, and the two other PSFCHs may be configured in the last symbols of time slot n and time slot n+1, respectively.

[0148] In some embodiments, the first sidelink channel configured using multiple PSFCHs may further include multiple SCI-2s. Each SCI-2 of the multiple SCI-2s may correspond to a respective PSFCH of the multiple PSFCHs, and each time domain resource for the multiple SCI-2s may correspond to a respective time slot of multiple consecutive time slots. For example, each time slot of the above-mentioned three time slots may correspond to a respective SCI-2, and the time domain resource for each SCI-2 may be the first few symbols of each time slot excluding AGC.

[0149] In some embodiments, HARQ codes for multiple PSFCHs may be considered separately based on each timeslot, or multiple HARQs may form a single HARQ, for example, an "AND" calculation may be performed on HARQ feedback from multiple timeslots to form the HARQ.

[0150] In some embodiments, the at least one PSFCH carries feedback information related to the first PSSCH. The first PSSCH may be associated with multiple PSFCH transmission resources on the shared spectrum, and the multiple PSFCH transmission resources may be configured to transmit the at least one PSFCH described above. Figure 5 illustrates the association of the first PSSCH with the multiple PSFCH transmission resources and is not repeated here.

[0151] In some embodiments, the terminal device may configure the transmission frame structure of the PSFCH according to different service modes or quality control information (QCI). A frame structure that meets service requirements or QCI requirements can facilitate improved transmission efficiency.

[0152] It can be seen that for multiple consecutive time slots transmitted each time in consecutive slot transmission, ACK / NACK is fed back by HARQ through PSFCH. Multiple consecutive time slots can flexibly provide PSFCH feedback through SCI configuration according to service or other requirements.

[0153] For ease of understanding, the frame structure of multiple consecutive time slots will be briefly described in connection with Figures 7 and 8, taking consecutive slot transmission using three time slots as an example. Figure 7 shows a schematic diagram of the frame structure of three time slots configured using one PSFCH. Figure 8 shows a schematic diagram of the frame structure of three time slots configured using three PSFCHs.

[0154] Referring to Figure 7, time slots 710, 720, and 730 are three consecutive time slots aggregated into a time slot (not shown). The first symbol of time slot 710 is AGC. SCI-1 is configured from the second symbol to the fourth symbol of time slot 710, and SCI-2 is configured from the second symbol to the third symbol of time slot 710. PSFCH is configured in the penultimate symbol of time slot 730. The last symbol of time slot 730 is a GAP. All other symbols of the aggregated time slot are configured to transmit PSSCH.

[0155] As shown in FIG. 7, in the first transmission block formed by three consecutive time slots, only one PSFCH is configured in the last time slot, and SCI-1 and SCI-2 are configured in the first time slot.

[0156] Referring to FIG. 8, an aggregated timeslot (not shown) is formed by three consecutive timeslots: timeslot 810, timeslot 820, and timeslot 830.

[0157] The main difference between Figure 8 and Figure 7 is the number and configuration of SCI-2s and PSFCHs. As shown in Figure 8, the frame structure shown in Figure 8 includes three PSFCHs and three SCI-2s. The three SCI-2s are configured in the second and third symbols of time slots 810, 820, and 830, respectively. Of the three PSFCHs, two PSFCHs are configured in the last symbols of time slots 810 and 820, respectively, and one PSFCH is configured in the penultimate symbol of time slot 830.

[0158] The above describes in detail embodiments relating to a method according to the present disclosure in relation to Figures 5 to 8. Embodiments relating to a device according to the present disclosure are described in detail below in relation to Figures 9 to 11. It should be understood that the description of the embodiment relating to the device corresponds to the description of the embodiment relating to the method. Therefore, content not described in detail may refer to the previous embodiment relating to the method.

[0159] 9 is a schematic block diagram of a communication device according to some embodiments of the present disclosure. The device 900 may be any of the terminal devices shown above. The device 900 shown in FIG. 9 includes a receiving unit 910, an access unit 920, and a transmitting unit 930.

[0160] The receiving unit 910 may be configured to receive the first PSSCH.

[0161] The access unit 920 may be configured to perform channel access on the shared spectrum, where the first PSSCH is associated with multiple PSFCH transmission resources on the shared spectrum, and the multiple PSFCH transmission resources are determined based on reserved resources, dynamic resources, or reserved and dynamic resources on the shared spectrum.

[0162] The transmitting unit 930 may be configured to transmit a first PSFCH using one PSFCH transmission resource of the plurality of PSFCH transmission resources, where the first PSFCH carries feedback information related to the first PSFCH.

[0163] In some embodiments, the plurality of PSFCH transmission resources is determined based on at least one of reserved resources or dynamic resources on the shared spectrum.

[0164] In some embodiments, the reserved resources are associated with a first indication information, the first indication information being determined based on at least one of: the maximum number of resource blocks required by each PSFCH transmission resource of the plurality of PSFCH transmission resources; the number of first sidelink time domain units within the reserved resources; the number of resource blocks configured for PSFCH transmission within the first sidelink time domain unit; the number of PSFCH transmission resources in the first sidelink time domain unit; or the service type corresponding to the first PSFCH.

[0165] In some embodiments, the first indication information is carried within the first sidelink control information.

[0166] In some embodiments, the reserved resources include M PSFCH transmission resources, and the first indication information IndexTO corresponding to the j-th PSFCH transmission resource among the M PSFCH transmission resources satisfies the following equation:

[0167]

number

[0168] where j is an integer ranging in value from 0 to M-1, n represents the number of first sidelink time domain units in the reserved resources, m represents the number of resource blocks configured for PSFCH transmission within the first sidelink time domain unit, and M S denotes the number of PSFCH transmission resources in the first sidelink time domain unit.

[0169] In some embodiments, the terminal device further includes a determining unit configured to determine whether there are idle PSFCH transmission resources among the reserved resources, and the transmitting unit is further configured to transmit the first PSFCH using dynamic resources in response to the absence of idle PSFCH transmission resources among the reserved resources.

[0170] In some embodiments, in response to the feedback information being a NACK, the first PSFCH is transmitted based on the information of the NACK.

[0171] In some embodiments, the transmitting unit is further configured to terminate transmission of the first PSFCH in response to the number of NACKs exceeding a first threshold.

[0172] In some embodiments, the terminal device further includes a listening unit configured to perform channel listening on the shared spectrum, and the transmitting unit is further configured to determine whether to transmit the first PSFCH using short control signaling based on a result of the channel listening.

[0173] In some embodiments, the transmitting unit is further configured to transmit the first PSFCH using short control signaling in response to the number of channel listening failures exceeding a second threshold.

[0174] 10 is a schematic block diagram of another communication device according to some embodiments of the present disclosure. The device 1000 may be any of the terminal devices described above. The device 1000 shown in FIG. 10 includes a listening unit 1010 and a transmitting unit 1020.

[0175] The listening unit 1010 may be configured to perform channel listening on the shared spectrum.

[0176] The transmitting unit 1020 may be configured to transmit the first sidelink channel by consecutive slot transmissions corresponding to a plurality of consecutive time slots, wherein a first transmission block carried by the first sidelink channel comprises transmission data corresponding to the plurality of consecutive time slots, and wherein the first sidelink channel comprises at least one PSFCH.

[0177] In some embodiments, the first sidelink channel includes one PSFCH, referred to as the first PSFCH, the last symbol of the last time slot of the plurality of consecutive time slots is referred to as the first symbol, and the time domain resource for the first PSFCH includes one symbol adjacent to the first symbol.

[0178] In some embodiments, the first sidelink channel further includes one second stage SCI, and the time domain resource for the second stage SCI is within a first time slot of a plurality of consecutive time slots.

[0179] In some embodiments, the first sidelink channel includes a plurality of PSFCHs, including a second PSFCH and at least one other PSFCH, and the plurality of consecutive time slots includes a last time slot and at least one other time slot. The last symbol of the last time slot is referred to as the second symbol, and the last symbol of the at least one other time slot is referred to as the third symbol. The time domain resource for the second PSFCH includes one symbol adjacent to the second symbol, and the time domain resource for the at least one other PSFCH includes the third symbol.

[0180] In some embodiments, the first sidelink channel further includes a plurality of second-stage SCIs, each time domain resource of the plurality of second-stage SCIs corresponding to a respective time slot of the plurality of consecutive time slots.

[0181] In some embodiments, at least one PSFCH carries feedback information related to a first PSFCH, the first PSFCH being associated with a plurality of PSFCH transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being configured to transmit the at least one PSFCH.

[0182] 11 is a schematic structural diagram of a communication device according to some embodiments of the present disclosure. The dashed lines in FIG. 11 indicate that a unit or module is optional. The device 1100 may be used to implement the methods described in the above embodiments. The device 1100 may be a chip or a terminal device.

[0183] The device 1100 may include at least one processor 1110. The processor 1110 may assist the device 1100 in implementing the methods described in the above embodiments related to the methods. The processor 1110 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0184] The device 1100 may further include at least one memory 1120. The memory 1120 is configured to store a program that, when executed by the processor 1110, causes the processor 1110 to perform the operations of the method illustrated in the above embodiments related to the method. The memory 1120 may be separate from the processor 1110 or integrated with the processor 1110.

[0185] The device 1100 may further include a transceiver 1130. The processor 1110 may communicate with other devices or chips through the transceiver 1130. For example, the processor 1110 may send and receive data to and from other devices or chips through the transceiver 1130.

[0186] Some embodiments of the present disclosure provide a non-transitory computer-readable storage medium configured to store a program. The non-transitory computer-readable storage medium is applicable to a terminal device or a network device provided by the embodiments of the present disclosure. When the program is executed, the computer performs the operations of a method performed by the terminal device or the network device according to the embodiments of the present disclosure.

[0187] It should be understood that the non-transitory computer-readable storage medium provided in the embodiments of the present disclosure may be any computer-readable and available medium, or a data storage device such as a server or data center that includes an integration of one or more available media. The available medium may be a magnetic medium (such as a floppy disk, hard drive, magnetic tape), an optical medium (such as a digital video disk (DVD)), a semiconductor medium (such as a solid-state disk (SSD)), etc.

[0188] Some embodiments of the present disclosure provide a computer program product including a program, which is applicable to a terminal device or a network device provided by the embodiments of the present disclosure, and when the program is executed, causes a computer to perform operations of a method performed by the terminal device or the network device according to the embodiments of the present disclosure.

[0189] The above embodiments may be implemented completely or partially by software, hardware, firmware, or any combination thereof. When implemented using software, the above embodiments may be implemented completely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded into a computer and executed, all or part of the processes or functions described in the embodiments of the present disclosure are performed. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another; for example, the computer instructions may be transmitted from a website, computer, server, or data center to another website site, computer, server, or data center via a wired method (such as coaxial cable, optical fiber, or digital subscriber line (DSL)) or a wireless method (such as infrared, wireless, or microwave).

[0190] Some embodiments of the present disclosure provide a computer program, which is applicable to a terminal device or a network device provided by the embodiments of the present disclosure, and when the computer program is executed, causes a computer to perform operations of a method performed by the terminal device or the network device according to the embodiments of the present disclosure.

[0191] The terms "system" and "network" in this disclosure may be used interchangeably. Additionally, the terms used in this disclosure are intended only to illustrate particular embodiments of the present disclosure and are not intended to limit the present disclosure. The terms "first," "second," "third," and "fourth" in the description, claims, and accompanying drawings of this disclosure are used to distinguish different objects, not to describe a particular order. Furthermore, the terms "including" and "having," and all variations thereof, are intended to include a non-exclusive inclusion.

[0192] In embodiments of the present disclosure, the "indication" referred to may be a direct indication, an indirect indication, or a representation of a relevant relationship. For example, A indicates B, which may indicate that A directly indicates B, e.g., B may be obtained through A, or that A indirectly indicates B, e.g., A indicates C, and B may be obtained through C, or that an association between A and B exists.

[0193] In embodiments of the present disclosure, the term "corresponding to" may indicate a direct or indirect correspondence between two objects, a correlation between two objects, or a relationship of indicating and indicated, or a relationship of constituting and constituting.

[0194] In an embodiment of the present disclosure, "pre-configuration" may be implemented by pre-storing corresponding codes, tables, or other methods that can be used to indicate relevant information in devices (such as terminal devices and network devices). The present disclosure is not limited to a specific implementation.

[0195] In the embodiments of the present disclosure, the term "protocol" may refer to a standard protocol in the communication field, such as an LTE protocol, an NR protocol, and related protocols applied in future communication systems. The present disclosure is not limited thereto.

[0196] In the embodiments of the present disclosure, determining B based on A does not only mean determining B based on A, but B may also be determined based on A and / or other information.

[0197] In the embodiments of the present disclosure, the term "and / or" is simply a description of an associative relationship between related objects, and indicates that three types of relationships may exist. For example, A and / or B may represent three situations: A only, A and B, and B only. Furthermore, the character " / " in the present disclosure generally indicates that the related objects have an "or" relationship.

[0198] In the embodiments of the present disclosure, the sequential numbers of the above processes do not imply an execution order, and the execution order of the processes should be determined based on the functions and internal logic of the processes, and should not constitute any limitation on the implementation process of the embodiments of the present disclosure.

[0199] It should be understood that the disclosed systems, devices, and methods may be implemented differently in the embodiments of the present disclosure. For example, the above-described device embodiments are merely illustrative. For example, the division of units is merely a division of logical functions, and other division methods may be used in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not implemented. Meanwhile, the illustrated or discussed couplings or direct couplings or communication connections between each other may be indirect couplings or communication connections through some interfaces, devices, or units, which may be electrical, mechanical, or in other forms.

[0200] Units described as separate components may or may not be physically separated, and components shown as units may or may not be physical units, i.e., located in one location or distributed across multiple network units. Some or all of the units may be selected according to actual needs to achieve the objectives of the present disclosure.

[0201] In addition, each functional unit of each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically independently, or two or more units may be integrated into one unit.

[0202] The above is merely a specific implementation of the present disclosure, and the scope of protection of the present disclosure is not limited thereto. Any modifications or replacements that can be easily conceived by a person skilled in the art within the scope of the technology disclosed in the present disclosure should be included in the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the claimed scope of protection. [Explanation of symbols]

[0203] 100 Wireless Communication System 110 Network Devices 121~129 Terminal Devices 200 V2X communication system 201~205 Terminal devices 710 time slots 720 time slots 730 time slots 810 time slots 820 time slots 830 time slots 900 devices 910 receiving unit 920 access units 930 sending unit 1000 devices 1010 Listening Unit 1020 Transmitting Unit 1100 devices 1110 processor 1120 memory 1130 Transceiver

Claims

1. 1. A method for sidelink communication, comprising: receiving, by a terminal device, a first physical sidelink shared channel (PSSCH); performing channel access on a shared spectrum by the terminal device, wherein the first PSSCH is associated with a plurality of Physical Sidelink Feedback Channel (PSFCH) transmission resources on the shared spectrum, and the plurality of PSFCH transmission resources are determined based on reserved resources, dynamic resources, or the reserved resources and the dynamic resources on the shared spectrum; transmitting, by the terminal device, a first PSFCH using one PSFCH transmission resource of the plurality of PSFCH transmission resources, the first PSFCH carrying feedback information related to the first PSFCH; A method comprising:

2. The reserved resource is associated with first indication information, and the first indication information is a maximum number of resource blocks required by each PSFCH transmission resource of the plurality of PSFCH transmission resources; the number of first sidelink time domain units within the reserved resources; the number of resource blocks configured for PSFCH transmission in the first sidelink time domain unit; the number of PSFCH transmission resources in the first sidelink time domain unit, or a service type corresponding to the first PSSCH The method of claim 1 , wherein the determination is based on at least one of:

3. 3. The method of claim 2, wherein the first indication information is carried within first sidelink control information.

4. The reserved resources include M PSFCH transmission resources, and first indication information IndexTO corresponding to a j-th PSFCH transmission resource among the M PSFCH transmission resources is [Equation 1] where j is an integer ranging in value from 0 to M-1, n represents the number of the first sidelink time domain units in the reserved resources, m represents the number of resource blocks configured for PSFCH transmission within the first sidelink time domain unit, and M S 4. The method of claim 2, wherein ∑ i = 1 ⁢ ... represents the number of PSFCH transmission resources in a first sidelink time domain unit.

5. after performing channel access on the shared spectrum by the terminal device; determining, by the terminal device, whether there is an idle PSFCH transmission resource among the reserved resources; transmitting, by the terminal device, the first PSFCH using the dynamic resource in response to an absence of an idle PSFCH transmission resource among the reserved resources; 5. The method of claim 1, further comprising:

6. 6. The method according to claim 1, further comprising: in response to the feedback information being a negative acknowledgement (NACK), transmitting the first PSFCH based on information of the NACK.

7. 7. The method of claim 6, further comprising: terminating transmission of the first PSFCH by the terminal device in response to a number of NACKs exceeding a first threshold.

8. before performing channel access on the shared spectrum by the terminal device; performing channel listening on the shared spectrum by the terminal device; determining, by the terminal device, based on a result of the channel listening, whether to transmit the first PSFCH using short control signaling; 8. The method of claim 1, further comprising:

9. 9. The method of claim 8, further comprising transmitting, by the terminal device, the first PSFCH using the short control signaling in response to the number of channel listening failures exceeding a second threshold.

10. 1. A method for sidelink communication, comprising: performing channel listening on the shared spectrum by a terminal device; transmitting, by the terminal device, a first sidelink channel by successive slot transmissions in response to the channel listening result being an idle channel; Including, the consecutive slot transmissions correspond to a plurality of consecutive time slots, a first transmission block carried by the first sidelink channel comprises transmission data corresponding to the plurality of consecutive time slots, and the first sidelink channel comprises at least one physical sidelink feedback channel (PSFCH).

11. 11. The method of claim 10, wherein the first sidelink channel includes one PSFCH, referred to as a first PSFCH, a last symbol of a last time slot of the plurality of consecutive time slots is referred to as a first symbol, and time domain resources for the first PSFCH include one symbol adjacent to the first symbol.

12. 12. The method of claim 11, wherein the first sidelink channel further includes one second-stage sidelink control information (SCI), and the time domain resource for the second-stage SCI is within a first time slot of the plurality of consecutive time slots.

13. 11. The method of claim 10, wherein the first sidelink channel includes a plurality of PSFCHs, including a second PSFCH and at least one other PSFCH, the plurality of consecutive time slots including a last time slot and at least one other time slot, a last symbol of the last time slot being referred to as a second symbol and a last symbol of the at least one other time slot being referred to as a third symbol, time domain resources for the second PSFCH including one symbol adjacent to the second symbol, and time domain resources for the at least one other PSFCH including the third symbol.

14. 14. The method of claim 13, wherein the first sidelink channel further includes a plurality of second-stage sidelink control information (SCIs), each time domain resource of the plurality of second-stage SCIs corresponding to a respective time slot of the plurality of consecutive time slots.

15. 15. The method of claim 10, wherein the at least one PSFCH carries feedback information related to a first physical sidelink shared channel (PSSCH), the first PSSCH being associated with a plurality of PSFCH transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being configured to transmit the at least one PSFCH.

16. 1. A device for sidelink communication, the device being a terminal device, the terminal device comprising: a receiving unit configured to receive a first physical sidelink shared channel (PSSCH); an access unit configured to perform channel access on a shared spectrum, wherein the first PSSCH is associated with a plurality of Physical Sidelink Feedback Channel (PSFCH) transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being determined based on reserved resources, dynamic resources, or the reserved resources and the dynamic resources on the shared spectrum; and a transmitting unit configured to transmit a first PSFCH using one PSFCH transmission resource of the plurality of PSFCH transmission resources, the first PSFCH carrying feedback information related to the first PSFCH; Including, the device.

17. The reserved resource is associated with first indication information, and the first indication information is a maximum number of resource blocks required by each PSFCH transmission resource of the plurality of PSFCH transmission resources; the number of first sidelink time domain units within the reserved resources; the number of resource blocks configured for PSFCH transmission in the first sidelink time domain unit; the number of PSFCH transmission resources in the first sidelink time domain unit, or a service type corresponding to the first PSSCH The device of claim 16, wherein the determination is based on at least one of:

18. 20. The device of claim 17, wherein the first indication information is carried within first sidelink control information.

19. The reserved resources include M PSFCH transmission resources, and first indication information IndexTO corresponding to a j-th PSFCH transmission resource among the M PSFCH transmission resources is [Equation 2] where j is an integer ranging in value from 0 to M-1, n represents the number of the first sidelink time domain units in the reserved resources, m represents the number of resource blocks configured for PSFCH transmission within the first sidelink time domain unit, and M S 19. The device of claim 17, wherein ∑ i = ∑ i = 1 ⁢ ... represents the number of PSFCH transmission resources in a first sidelink time domain unit.

20. The terminal device, a determining unit configured to determine whether there is an idle PSFCH transmission resource among the reserved resources; 20. The device of claim 16, wherein the transmitting unit is further configured to transmit the first PSFCH using the dynamic resource in response to an absence of an idle PSFCH transmission resource among the reserved resources.

21. 21. The device of claim 16, wherein, in response to the feedback information being a negative acknowledgement (NACK), the first PSFCH is transmitted based on information of the NACK.

22. 22. The device of claim 21, wherein the transmitting unit is further configured to terminate transmission of the first PSFCH in response to a number of NACKs exceeding a first threshold.

23. The terminal device, further comprising a listening unit configured to perform channel listening on the shared spectrum; 23. The device of claim 16, wherein the transmitting unit is further configured to determine, based on a result of the channel listening, whether to transmit the first PSFCH using short control signaling.

24. 24. The device of claim 23, wherein the transmitting unit is further configured to transmit the first PSFCH using the short control signaling in response to a number of channel listening failures exceeding a second threshold.

25. 1. A device for sidelink communication, the device being a terminal device, the terminal device comprising: a listening unit configured to perform channel listening on the shared spectrum; a transmitting unit configured to transmit a first sidelink channel by successive slot transmissions in response to a result of the channel listening being an idle channel; Including, the consecutive slot transmissions correspond to a plurality of consecutive time slots, a first transmission block carried by the first sidelink channel includes transmission data corresponding to the plurality of consecutive time slots, and the first sidelink channel includes at least one physical sidelink feedback channel (PSFCH).

26. 26. The device of claim 25, wherein the first sidelink channel includes one PSFCH, referred to as a first PSFCH, a last symbol of a last time slot of the plurality of consecutive time slots is referred to as a first symbol, and time domain resources for the first PSFCH include one symbol adjacent to the first symbol.

27. 27. The device of claim 26, wherein the first sidelink channel further includes one second-stage sidelink control information (SCI), and the time domain resource for the second-stage SCI is within a first time slot of the plurality of consecutive time slots.

28. 26. The device of claim 25, wherein the first sidelink channel includes a plurality of PSFCHs, including a second PSFCH and at least one other PSFCH, the plurality of consecutive time slots including a last time slot and at least one other time slot, a last symbol of the last time slot being referred to as a second symbol and a last symbol of the at least one other time slot being referred to as a third symbol, time domain resources for the second PSFCH including one symbol adjacent to the second symbol, and time domain resources for the at least one other PSFCH including the third symbol.

29. 30. The device of claim 28, wherein the first sidelink channel further includes a plurality of second-stage sidelink control information (SCIs), each time domain resource of the plurality of second-stage SCIs corresponding to a respective time slot of the plurality of consecutive time slots.

30. 30. The device of claim 25, wherein the at least one PSFCH carries feedback information related to a first physical sidelink shared channel (PSSCH), the first PSSCH being associated with a plurality of PSFCH transmission resources on the shared spectrum, the plurality of PSFCH transmission resources being configured to transmit the at least one PSFCH.

31. Memory and Processor and Including, A communications device, wherein the memory is configured to store a program that, when called and executed by the processor, causes the processor to perform the operations of the method of any one of claims 1 to 15.

32. 16. A device comprising a processor configured to invoke and execute a program stored in a memory to perform the operations of the method of any one of claims 1 to 15.

33. A chip including a processor configured to call and execute a program stored in memory to cause a device including the chip to perform the operations of the method of any one of claims 1 to 15.

34. 16. A non-transitory computer readable storage medium configured to store a program that, when invoked and executed, causes a computer to perform the operations of the method of any one of claims 1 to 15.

35. A computer program product comprising a program that when invoked and executed causes a computer to perform the operations of the method according to any one of claims 1 to 15.

36. A computer program product which, when invoked and executed, causes a computer to perform the operations of the method according to any one of claims 1 to 15.

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