Method and apparatus for transmitting a request message

Description

1 / 61 METHOD AND APPARATUS FOR TRANSMITTING A REQUEST MESSAGE FIELD OF TECHNIQUE

[001] The modalities of the present disclosure relate to the field of communications technology and, in particular, relate to a method and apparatus for transmitting a solicitation message. RELATED TECHNIQUE

[002] When operating in an unlicensed spectrum, an unlicensed spectrum side link terminal device (SL-U) needs to perform a listen-before-talk (LBT) procedure before transmitting data and, when performing a type 1 LBT procedure for channel access, the terminal device is forced to listen based on a channel access priority, consuming considerable power.

[003] Therefore, from the point of view of reducing energy consumption, how to save energy during a canal access procedure needs further research. SUMMARY

[004] The modalities of the present disclosure provide a method and an apparatus for transmitting solicitation messages.

[005] According to some embodiments of the present disclosure, a method for transmitting request messages is provided. The method is performed by a terminal device and includes:

[006] transmit a first request message, wherein the first request message is configured to request the sharing of a channel occupation time (COT) from at least one other device. Petition 870250086482, dated 09 / 24 / 2025, page 9 / 169 2 / 61 terminal.

[007] According to some embodiments of the present disclosure, an apparatus is provided for transmitting solicitation messages. The apparatus includes:

[008] a transmission module, configured to transmit a first request message, where the first request message is configured to request the sharing of a COT from at least one other terminal device. BRIEF DESCRIPTION OF THE DRAWINGS

[009] Figure 1 is a schematic diagram of a network architecture according to some embodiments of the present disclosure;

[0010] Figure 2 is a schematic diagram of side link communication in coverage according to some embodiments of the present disclosure;

[0011] Figure 3 is a schematic diagram of partial coverage side link communication according to some embodiments of the present disclosure;

[0012] Figure 4 is a schematic diagram of out-of-coverage side link communication according to some embodiments of the present disclosure;

[0013] Figure 5 is a schematic diagram of a centrally controlled side link communication via a central control node according to some embodiments of the present disclosure;

[0014] Figure 6 is a schematic point-to-point diffusion diagram according to some embodiments of the present disclosure;

[0015] Figure 7 is a schematic diagram of Petition 870250086482, dated 09 / 24 / 2025, p. 10 / 169 3 / 61 group dissemination in accordance with some of the modalities of the present disclosure;

[0016] Figure 8 is a schematic diffusion diagram according to some embodiments of the present disclosure;

[0017] Figure 9 is a schematic structural diagram of a partition excluding a physical side-link feedback channel (PSFCH) according to some embodiments of the present disclosure;

[0018] Figure 10 is a schematic structural diagram of a partition including a PSFCH according to some embodiments of the present disclosure;

[0019] Figure 11 is a schematic flowchart of a method for transmitting request messages according to some embodiments of the present disclosure;

[0020] Figure 12 is a schematic diagram of the separate transmission of a first solicitation message according to some embodiments of the present disclosure;

[0021] Figure 13 is a schematic diagram of the simultaneous transmission of a first request message and a second side link data according to some embodiments of the present disclosure;

[0022] Figure 14 is a schematic diagram of a side-link transmission grant state according to some embodiments of the present disclosure;

[0023] Figure 15 is a schematic diagram of a side-link transmission no-grant state according to some embodiments of the present disclosure;

[0024] Figure 16 is a block diagram. Petition 870250086482, dated 09 / 24 / 2025, page 11 / 169 4 / 61 schematic of an apparatus for transmitting solicitation messages according to some embodiments of the present disclosure;

[0025] Figure 17 is another schematic block diagram of an apparatus for transmitting solicitation messages according to some embodiments of the present disclosure; and

[0026] Figure 18 is a schematic structural diagram of a terminal device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0027] For a clearer description of the objectives, technical solutions and advantages of the present disclosure, the embodiments of the present disclosure are described in detail hereafter in this document in combination with the accompanying drawings.

[0028] The network architecture and business scenarios described in the embodiments of this disclosure are intended to illustrate the technical solutions according to the embodiments of this disclosure more clearly, but do not limit the technical solutions. Those skilled in the art understand that, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions according to the embodiments of this disclosure are also applicable to addressing similar technical problems.

[0029] Figure 1 is a block diagram of a network architecture according to some embodiments of the present disclosure. The network architecture involves a main network 11, an access network 12 and a terminal device 13. Petition 870250086482, dated 09 / 24 / 2025, page 12 / 169 5 / 61

[0030] The core network 11 includes several core network devices. Each of the core network devices has the primary function of providing user connectivity, user management, and service support, and is defined as a support network to provide an interface to an external network. For example, a core network of a 5G (5th generation) NR (new radio) system includes an access and mobility management (AMF) function entity, a user plane function entity, a session management function (SMF) entity, and other devices.

[0031] Access network 12 includes several access network devices 14. The access network in the 5G NR system is also called next-generation radio access network (NG-RAN). Each of the access network devices 14 is a device deployed in the access network 12 and configured to provide a wireless communication function to the terminal device 13. Access network devices 14 include various types of macro base stations, micro base stations, relay stations, access points, and the like. In systems using different radio access technologies, devices with access network device functionality have different names, for example, gNodeBs, or gNBs in 5G NR systems. With the evolution of communication technologies, the name access network device changes.For convenience, the devices that provide the wireless communication function for terminal device 13 are collectively referred to as the access network device in the embodiments of this disclosure.

[0032] Generally, a plurality of Petition 870250086482, dated 09 / 24 / 2025, p. 13 / 169 6 / 61 terminal devices 13 are provided. One or more terminal devices 13 may be deployed in a cell managed by each of the access network devices 14. Terminal devices 13 include various portable devices, vehicle-mounted devices, body-wearable devices, computing devices or other processing devices connected to wireless modems, various forms of user equipment (UEs), mobile stations (MSs), and other devices with wireless communication functionality. For convenience of description, the devices are collectively referred to as the terminal device. The access network device 14 and the terminal device 13 communicate with each other using an air interface technology, such as a Uu interface.

[0033] Terminal device 13 and terminal device 13 (e.g., vehicle-mounted device) and other devices (such as other vehicle-mounted devices, mobile phones, roadside units (RSUs), or similar) communicate with each other via a direct communication interface (e.g., a ProSe 5 Communication Interface (PC5)), and the communication link established via the direct communication interface is consequently referred to as a direct link or side link (SL). SL communication indicates that the transmission of communication data between terminal devices is carried out via SL, which is different from the traditional cellular system in which communication data is received or transmitted through the access network device. Thus, SL communication has characteristics of short delay and low overhead, being suitable for communication between two Petition 870250086482, dated 09 / 24 / 2025, page 14 / 169 7 / 61 terminal devices in geographically close locations (such as a vehicle device and other peripheral devices in geographically close locations). It should be noted that Figure 1 is illustrated using only an example of vehicle-to-vehicle communication in the V2X scenario, and the SL technology is applicable to the scenario where multiple terminal devices communicate directly with each other. In other words, the terminal device in the present disclosure is any device that implements communication using SL technology.

[0034] The 5G NR system in the embodiments of the present disclosure is also referred to as a 5G system or an NR system, and persons skilled in the art can understand the meaning. The solutions of the art according to the embodiments of the present disclosure are applicable to the NR 5G system and to evolved systems of the NR 5G system.

[0035] Before describing the technical solutions according to the present disclosure, some basic technical knowledge involved in the present disclosure is introduced and explained first. The following related technologies, as optional solutions, may be arbitrarily combined with the technical solutions according to the embodiments of the present disclosure, which are within the scope of protection of the embodiments of the present disclosure. The embodiments of the present disclosure include at least part of the following content.

[0036] 1. Communication via SL in different network coverage environments.

[0037] According to the network coverage conditions of the terminal devices, SL communication can be categorized into SL communication within coverage (all terminal devices are within network coverage), Petition 870250086482, dated 09 / 24 / 2025, page 15 / 169 8 / 61 partial coverage SL communication (not all terminal devices are within network coverage), out-of-coverage SL communication (none of the terminal devices are within network coverage), and centrally controlled SL communication by a central control node (the node implements management and scheduling in the communication), respectively, as illustrated in Figure 2, Figure 3, Figure 4, and Figure 5.

[0038] As illustrated in Figure 2, in SL communication within coverage, all terminal devices (e.g., UE 1 and UE 2) involved in SL communication are within the coverage range of the same base station. Therefore, all terminal devices can perform SL communication based on the same SL configuration, receiving configuration signaling from the base station.

[0039] As illustrated in Figure 3, in SL communication with partial coverage, one (such as UE 1) of the terminal devices is positioned within the coverage range of the base station. This terminal device is able to receive configuration signaling from the base station and perform SL communication based on a base station configuration. Meanwhile, the other (such as UE 2) of the terminal devices positioned outside the network coverage range cannot receive configuration signaling from the base station; and, in this case, the terminal device positioned outside the network coverage range can determine an SL configuration based on pre-configured information and information carried on a physical side link broadcast channel (PSBCH) transmitted by the terminal device positioned within the network coverage range. Petition 870250086482, dated 09 / 24 / 2025, page 16 / 169 9 / 61 thus enabling communication via SL.

[0040] As illustrated in Figure 4, with regard to SL communication outside the coverage area, all terminal devices that perform SL communication are positioned outside the network coverage range of the base station, and all terminal devices determine the SL configuration based on pre-configuration information, thus performing SL communication.

[0041] As illustrated in Figure 5, regarding SL communication centrally controlled by a central control node, a plurality of terminal devices (such as UE 1, UE 2, and UE 3) form a communication group, where the communication group has a central control node, alternatively called a cluster header (CH). The cluster header has one of the following capabilities: forming the communication group; adding or removing members; performing resource coordination and allocating SL transmission resources to other terminal devices; receiving L feedback information from other terminal devices; performing resource coordination with other communication groups, among others.

[0042] 2Device-to-device (D2D) / Vehicle-to-everything (V2X)

[0043] D2D communication is a D2D-based SL transmission technology. The transmission or reception of communication data via base station in D2D communication is different from that in a traditional cellular network. Therefore, D2D communication has superior spectral efficiency and lower transmission latency. A V2X system adopts terminal-to-terminal communication, defining two transmission modes in Petition 870250086482, dated 09 / 24 / 2025, page 17 / 169 10 / 61 related technique: a first mode and a second mode.

[0044] In the first mode: transmission resources are allocated by the base station to the terminal device, and the terminal device performs data transmission in SL based on the resources allocated by the base station; and the base station can allocate resources for a single transmission to the terminal device, or it can allocate resources for a semi-static / passive transmission to the terminal device. As illustrated in Figure 2, the terminal device is positioned within the network coverage range of the base station, where transmission resources are allocated by the network to the network device for SL transmission.

[0045] In the second mode: the network device selects resources for data transmission from a resource grouping. As illustrated in Figure 4, the terminal device is positioned outside the network coverage range of the base station, where the terminal device selects transmission resources from a set of resources preconfigured for SL transmission; or as illustrated in Figure 2, the terminal device selects transmission resources for SL transmission from the resource grouping configured by the network.

[0046] 3. NR-V2X

[0047] In NR-V2X, for autonomous driving, stringent requirements are being imposed on the exchange of data between vehicles, for example, greater productivity, lower latency, greater reliability, extended coverage and more flexible resource allocation.

[0048] Broadcast transmission is supported in Petition 870250086482, dated 09 / 24 / 2025, page 18 / 169 11 / 61 LTE-V2X, while in NR-V2X, point-to-point broadcast transmission and group broadcast transmission were introduced. Regarding point-to-point broadcast transmission, the receiving terminals include only a single terminal device. As illustrated in Figure 6, UE 1 and UE 2 perform point-to-point broadcast transmission; and regarding group broadcast transmission, the receiving terminals include all terminal devices within a communication group or all terminal devices positioned within a designated transmission range. As illustrated in Figure 7, UE 1, UE 2, UE 3, and UE 4 form a communication group, where UE 1 transmits data and all other terminal devices are receiving terminals; and regarding broadcast transmission, the receiving terminal is any of the terminal devices surrounding a transmitting terminal.As illustrated in Figure 8, in a case where UE 1 is the transmitting terminal, all other terminal devices around the transmitting terminal are the receiving terminals.

[0049] 4. Frame structure in the NR-V2X system

[0050] Figure 9 illustrates a partition range structure that excludes a physical side link return channel (PSFCH). Figure 10 illustrates a partition structure that includes a PSFCH.

[0051] As illustrated in Figure 9, a physical side link control channel (PSCCH) begins at the second SL symbol of the time-domain interval in NR-V2X, and occupies 2 or 3 orthogonal frequency-division multiplexing (OFDM) symbols, and may occupy {10, 12, 15, 20, 25} physical resource blocks (PRBs) in the frequency domain. In Petition 870250086482, dated 09 / 24 / 2025, page 19 / 169 12 / 61 In order to reduce the complexity of blind PSCCH detection by a UE, only a single number of PSCCH symbols and a single number of PRBs are allowed within a resource grouping. Furthermore, since the subchannel serves as the minimum unit for resource allocation of the Physical Side Link Shared Channel (PSSCH) in NR-V2X, the number of PRBs occupied by PSSCH must be less than or equal to the number of PRBs included in a subchannel within the resource grouping, so as not to cause additional limitations in the selection or allocation of PSSCH resources. PSSCH also starts from the second SL symbol in the partition in the time domain; the last time domain symbol in the partition is a guard period (GP) symbol, and the remaining symbols are used to map PSSCH.The first SL symbol in the partition is a repetition of the second SL symbol; the receiving terminal usually uses the first SL symbol as an automatic gain control (AGC) symbol, where the data in that symbol is generally not used for data demodulation. The PSSCH occupies K subchannels in the frequency domain, and each of the subchannels includes N contiguous PRBs.

[0052] As illustrated in Figure 10, if the partition includes the PSFCH, the penultimate and antepenultimate symbols in the partition are used for the transmission of the PSFCH, and a symbol in the time domain preceding the PSFCH serves as the GP symbol.

[0053] 5. Unlicensed and LBT Spectrum

[0054] An unlicensed spectrum is a communication spectrum available to wireless electrical devices designated by national or regional authorities; this communication spectrum is commonly referred to as a spectrum Petition 870250086482, dated 09 / 24 / 2025, page 20 / 169 13 / 61 shared, a communication device may operate in the spectrum on the premise of satisfying the applicable regulatory requirements established on the spectrum by national or regional authorities, but does not need to apply for an exclusive spectrum license from the national or regional authorities that exclusively manage spectrum. The communication device observes a "listen before you speak" principle to operate in the unlicensed spectrum, i.e., satisfying the regulatory requirements designated by various national or regional authorities.

[0055] For the harmonious coexistence of various communication systems in an unlicensed spectrum, some national or regional authorities have established regulatory requirements for the use of this spectrum. For example, the communication device must observe the listen-before-speak principle when conducting communication in the unlicensed spectrum. This means that the communication device must perform an LBT procedure before transmitting the signal in the unlicensed spectrum, i.e., channel detection. The communication device may only transmit the signal if the result of the channel detection indicates an idle state, i.e., after a successful LBT procedure; the communication device may not transmit the signal if the result of the channel detection indicates a busy state, i.e., after a failed LBT procedure.Furthermore, in order to ensure fair use of a spectrum resource in a shared spectrum, the duration of communication transmission carried out through the channel available to the communication device may not exceed a designated duration. Petition 870250086482, dated 09 / 24 / 2025, page 21 / 169 14 / 61 of the LBT procedure being successful for the communication device in the unlicensed spectrum. By limiting a maximum communication duration after a successful LBT procedure, this mechanism can give different communication devices the opportunity to access the shared channel, thus achieving the harmonious coexistence of different communication systems in the shared spectrum.

[0056] Although channel listening is not a universal regulatory mandate, it is considered an essential feature in the design of NR systems for operation in unlicensed spectrum. This is due to its crucial role in providing interference avoidance and ensuring friendly coexistence for transmissions between communication systems in a shared spectrum environment. From a network deployment perspective, channel detection includes two types of mechanisms: one type is LBT with load-based equipment (LBE), also referred to as dynamic channel detection or dynamic channel occupancy, while the other is LBT with frame-based equipment (FBE), also referred to as semi-static channel detection or semi-static channel occupancy.

[0057] 6. Dynamic channel detection

[0058] Dynamic channel sensing can also be understood as an LBT based on LBE. Dynamic channel sensing observes a channel sensing principle where the communication device executes an LBT procedure on an unlicensed spectrum carrier after traffic arrives and subsequently initiates signal transmission on the carrier after a successful LBT procedure. Dynamic channel sensing LBT includes type 1 channel access and type 2 channel access. Petition 870250086482, dated 09 / 24 / 2025, p. 22 / 169 15 / 61 2. Type-1 channel access is a multi-partition channel sensing with random offset and adjustable contention window size, where a Channel Access Priority Class (CAPC) p can be selected based on transmission traffic priority. Type-2 channel access is a fixed-length channel sensing-based channel access, where Type-2 channel access includes Type-2A channel access, Type-2B channel access, and Type-2C channel access. Type-1 channel access is mainly used for the communication device to initiate channel occupancy, and Type-2 channel access is mainly used for the communication device to share channel occupancy.

[0059] Channel Access Type-1:

[0060] The communication device must first detect a channel within a period Td. When it detects that all detection partitions are idle and an N in the following procedure is equal to 0, the LBT procedure is successful and the communication device can occupy the channel for data transmission. Otherwise, the LBT procedure fails and the communication device cannot access the channel.

[0061] Step 1: The communication device sets N=Ninit, where Ninit is a random value from 0 to CWp, and the process jumps to step 4.

[0062] Step 2: In a case where N>0, the communication device subtracts 1 from N and sets N=N-1.

[0063] Step 3: The communication device continues to detect a channel with a length within a detection partition; and, in the case where the channel is idle, the process advances to step 4, and otherwise, the process Petition 870250086482, dated 09 / 24 / 2025, p. 23 / 169 16 / 61 advances to stage 5.

[0064] Step 4: In a case where N=0, the process is interrupted; otherwise, the process skips to step 2.

[0065] Step 5: The communication device continues to detect the channel until a detection partition within the Td period is detected as busy, or all detection partitions within the Td period are detected as idle.

[0066] Step 6: In a case where all detection partitions within the Td period are idle, the process skips to step 4, and otherwise, the process skips to step 5.

[0067] For the above steps, in the case of a jump not being clearly indicated, the steps must be executed in order. A single detection partition in the above aspect is a duration TS1, where TS1 is equal to 9 μs.

[0068] Ninit is a random value from 0 to CWp. CWp is associated with a channel priority of a communication device. CWp may also be referred to as a corresponding designated priority contention window (CW), or a contention window based on priority determination. The communication device determines a CWmin,p, CWmax,pe value of an allowed CWp based on a channel access priority, i.e., the communication device determines a minimum value, a maximum value, and possible values ​​of the contention window based on the priority. For example, in Table 1, in a case where the channel access priority is 3, the minimum value, the maximum value, and the possible values ​​of the contention window are 15, 1023 and {15, 31, 63, 127, 255, 511, Petition 870250086482, dated 09 / 24 / 2025, p. 24 / 169 17 / 61 1023}, respectively. In practice, the communication device maintains a contention window size corresponding to each priority, adjusts the contention window corresponding to each priority according to the rules before executing step 1, and determines the contention window for a current LBT procedure according to the channel access priority, thus determining Ninit. TABLE 1: CHANNEL ACCESS PRIORITY Priority of access to the channel (p) mp CWmin,p CWmax,p Tmcot,p Allowed CWp value 1 2 3 7 2 ms {3, 7} 2 2 7 15 4 ms {7, 15} 3 3 15 1023 6 or 10 ms {15, 31, 63, 127, 255, 511, 1023} 4 7 15 1023 6 or 10 ms {15, 31, 63, 127, 255, 511, 1023}

[0069] In the already mentioned Td=Tf+mp*Tsl, where Tf is equal to 16 μs, and mp is related to the channel access priority. For example, mp can be determined from Table 1 based on the priority.

[0070] If the communication device is unable to immediately access the channel after performing the aforementioned steps and a successful LBT, the communication device does not need to execute the entire Type 1 LBT procedure when it needs access to the channel for data transmission. Instead, the communication device only requires the detection of an occupied Td+ state by the Petition 870250086482, dated 09 / 24 / 2025, page 25 / 169 18 / 61 minus one channel within a Tsi period; and, in the case where the state is detected as idle, the communication device can directly access the channel for signal transmission.

[0071] After successful access to the LBT and channel, the duration of channel occupation is called COT. Within the COT, the communication device can perform continuous or non-continuous transmissions; however, the transmission time cannot exceed a Tmcot,p. The Tmcot,p is related to the channel access priority, as listed in Table 1. The communication device does not need to transmit within the COT. Therefore, the communication device can share the COT with other devices, i.e., the communication device can transmit its own COT information to other devices, and after receiving the COT information, the other devices only need to perform channel type 2 access to share and access the channel.

[0072] Channel Access Type-2:

[0073] · Type-2A channel access:

[0074] One way of UE channel detection uses a single 25 μs partition channel detection. More specifically, using type 2A channel access, UE can perform 25 μs channel detection before transmission and perform transmission after successful channel detection.

[0075] • Type-2B channel access:

[0076] One way of UE channel detection uses a single 16 μs partition channel detection. More specifically, using type 2B channel access, UE can perform 16 μs channel detection before transmission and perform transmission after successful channel detection, where the size of a gap between the initial position of Petition 870250086482, dated 09 / 24 / 2025, p. 26 / 169 19 / 61 a current transmission and the final position of a previous transmission is 16 μs.

[0077] · Type-2C channel access:

[0078] The UE performs transmission without channel detection after the end of the interval. More specifically, using type-2C channel access, the UE can perform transmission directly, where the size of an interval between the start position of a current transmission and the end position of a previous transmission is less than or equal to 16 μs, and the transmission duration cannot exceed 584 μs.

[0079] 7. RedCap

[0080] Reduced Capability (RedCap) is a 5G technology within related technology. Compared to 4G, 5G has significant advantages in terms of communication speed, latency, reliability, and the like. However, this increases both the design complexity and the cost of a terminal as a consequence. The high terminal costs make many practical commercial deployment scenarios unacceptable. In these scenarios, the communication requirements for terminal devices are stringent, and full-capacity 5G is not necessary. However, stringent requirements are imposed on cost and power consumption. Therefore, to balance functionality and cost, and to better accommodate the demands for lower cost and lower power consumption in the industrial internet and the Internet of Things, RedCap device types have been defined in related techniques.A RedCap terminal device can reduce the cost and power consumption of the terminal device by decreasing bandwidth, reducing the number of antennas, reducing the modulation level, and so on. Furthermore... Petition 870250086482, dated 09 / 24 / 2025, page 27 / 169 20 / 61 Two types of energy-saving mechanisms have been standardized in related techniques, and the energy consumption of the terminal device can be reduced even further.

[0081] Currently, standardization efforts are underway to deploy SL technology in unlicensed spectrum, known as SL-U technology. SL-U can be implemented in commercial scenarios such as smart wearables, smart homes, the industrial internet, and similar applications. Discussions assume that all terminals have equal capabilities without considering reduced-capacity terminals. However, cost and power consumption are crucial metrics for commercial deployment, and the lower cost and lower power consumption offered by reduced-capacity terminals may facilitate the commercialization of SL-U technology. Therefore, standardization of RedCap SL-U technology is worth considering. Consequently, from the perspective of low power consumption, how to optimize energy efficiency remains an issue to be addressed.

[0082] When operating in the unlicensed spectrum, the SL-U terminal must perform LBT before data transmission. The terminal needs to confirm a random withdrawal counter size when performing type 1 channel access, where a value of N is a random value within CWp. For example, when CAPC is 4, a CWp value is 1023, and assuming N=10000, the terminal performing type 1 channel access requires at least Td+N*Tsl = Tf+mp*TSl+N*TSl = 16 + 7*9 + 1000*9 = 9079 ps, meaning the RedCap terminal needs to listen for at least 9 ms continuously, causing high power consumption. Therefore, how to optimize energy efficiency in the channel access process? Petition 870250086482, dated 09 / 24 / 2025, p. 28 / 169 21 / 61 remains an issue that needs to be addressed.

[0083] With reference to Figure 11, a schematic flowchart of a method for transmitting request messages according to some embodiments of the present disclosure is illustrated, being applicable to a network structure in Figure 1. The method is performed by a terminal device and includes step 1110 below.

[0084] In step 1110, the terminal device transmits a first request message, in which the first request message is used to request the sharing of a COT from at least one other terminal device.

[0085] COT refers to the channel occupation time after a successful access to the terminal device channel in a type 1 channel access mechanism. For example, COT refers to the channel occupation time after a successful access to the terminal device channel in a type 1 LBT procedure.

[0086] In some embodiments, the terminal device may transmit data continuously or may transmit data discreetly within the COT. In a scenario where the terminal device does not need to transmit data continuously, the terminal device may share the COT with other terminal devices, and the other terminal devices may execute a type 2 channel access mechanism on the shared COT. For example, terminal devices may execute a type 2 LBT procedure on the shared COT.

[0087] At least one other terminal device may be the other devices above, a plurality of terminal devices may also be the other devices Petition 870250086482, dated 09 / 24 / 2025, p. 29 / 169 22 / 61 above, which is not limited to the present disclosure.

[0088] In some modes, the terminal transmits a first request message in the case where a first condition is met, with the first condition including at least one of the following:

[0089] the terminal device being a reduced capacity terminal device;

[0090] the first SL data available on a logical channel of the terminal device;

[0091] a value of a channel access priority corresponding to the first SL data in the logical channel of the terminal device being greater than or equal to a first limit;

[0092] a value of a containment window corresponding to the first SL data in the logical channel of the terminal device being greater than or equal to a second limit; or

[0093] a value of a random back counter in a type 1 channel access mechanism corresponding to the first SL data in the terminal device's logical channel is greater than or equal to a third limit.

[0094] A RedCap terminal device is a terminal device with lower communication capabilities, and full 5G capability is not required. In a typical scenario, the RedCap terminal device reduces cost and power consumption by decreasing bandwidth, reducing the number of antennas, decreasing the modulation level, and so on. The RedCap terminal device shares the COT (Cost of Technology) of at least one other terminal device when transmitting the first request message to at least one other terminal device. Petition 870250086482, dated 09 / 24 / 2025, page 30 / 169 23 / 61 thus reducing the energy required for the LBT type 1 procedure and reducing energy consumption.

[0095] The term first available SL data refers to the first SL data pending transmission or the first SL data that requires transmission. The logical channel of the terminal device containing available SL data can be understood as the terminal device possessing the first SL data that needs to be transmitted.

[0096] Specific values ​​of the first limit, second limit, and third limit are not limited in the present disclosure. For example, the first limit is 3, meaning the value of the access priority to the first available SL data channel on the logical channel of the terminal device is greater than or equal to 3. For example, the second limit is 15, meaning the value of the contention window for the first available SL data on the logical channel of the terminal device is greater than or equal to 15.

[0097] More specifically, with regard to the Type 1 LBT procedure, the contention window needs to be determined based on the access priority to the channel corresponding to the first available SL data on the terminal device's logical channel, and therefore, the Type 1 LBT procedure is performed based on the contention window. Generally, the higher the channel access priority value, the larger the contention window value. In this way, a larger contention window is achieved, the duration required for the Type 1 LBT procedure is extended, and the terminal device's power consumption is increased. On the other hand, in a case where the channel access priority value is Petition 870250086482, dated 09 / 24 / 2025, page 31 / 169 24 / 61 smaller, the containment window value is smaller. In this case, the duration required for the type 1 LBT procedure is not long, the energy consumption of the terminal device is lower, and therefore there is no need to request the sharing of COTs from other terminal devices.

[0098] As listed in Table 1, the higher the channel access priority value, the lower the channel access priority; and the lower the channel access priority value, the higher the channel access priority.

[0099] Similarly, the value of the random withdrawal counter generated during the type 1 LBT procedure also influences the duration required for the type 1 LBT procedure; the higher the value of the random withdrawal counter, the longer the duration required for the type 1 LBT procedure, and the lower the value of the random withdrawal counter, the shorter the duration required for the type 1 LBT procedure.

[00100] In some embodiments, the first limit, the second limit, and the third limit are configured by a network, or are pre-configured, or depend on the implementation of the terminal device, or are predefined, which are not limited in the present disclosure.

[00101] The first condition may include one or a plurality of conditions. If the condition includes a plurality of conditions, the conditions may be freely combined.

[00102] For example, the first condition may include: the terminal device being the RedCap terminal device; and the first SL data being available on the channel. Petition 870250086482, dated 09 / 24 / 2025, p. 32 / 169 25 / 61 Terminal device logic.

[00103] For example, the first condition may include: the terminal device being the RedCap terminal device; the first SL data being available on the terminal device's logical channel; and the access priority value for the channel corresponding to the first SL data on the terminal device's logical channel being greater than or equal to a first limit;

[00104] For example, the first condition may include: the terminal device being the RedCap terminal device; the value of the containment window corresponding to the first SL data in the terminal device's logical channel being greater than or equal to a second limit; and the value of the random back counter in the type 1 channel access mechanism corresponding to the first SL data in the terminal device's logical channel being greater than or equal to a third limit.

[00105] Similarly, the present disclosure does not list all the cases contained in this document.

[00106] In some embodiments, the first request message is carried by means of SL control information (SCI), or the first request message is carried by means of a medium access control (MAC) element.

[00107] In some embodiments, the message of the first request may be transported via first-stage SCI, or via second-stage SCI, or via a combination of first-stage SCI and second-stage SCI.

[00108] In some modes, the CE MAC for carrying the first request message receives a higher priority. Petition 870250086482, dated 09 / 24 / 2025, page 33 / 169 26 / 61

[00109] In some modes, the resource for transmitting the first request message is allocated by the network or is selected by the terminal device.

[00110] In some modes, whether the first request is carried via SCI or MAC CE, the terminal device needs to transmit a PSCCH along with an associated PSSCH to transmit the SCI or MAC CE; and therefore, the resources in the time domain to transmit the PSCCH and the associated PSSCH need to be determined. An SL transmission supports two modes. In a first mode, the terminal device transmits a scheduling request to the network device, and the network device allocates a resource to transmit the SCI or MAC CE. In a second mode, the terminal device selects a resource to transmit the SCI or MAC CE.

[00111] In some modes, the first request is transmitted by means of any of the following options: point-to-point broadcast, group broadcast or broadcast.

[00112] For example, the first request message is transmitted by point-to-point broadcast, and UE 1 transmits the first request message to UE 2 by point-to-point broadcast.

[00113] For example, the first request message is transmitted by group broadcast, and UE 1 transmits the first request message to one of the terminal devices in a group broadcast, where the group broadcast includes UE 1, UE 2 and UE 3.

[00114] For example, the first request message is transmitted by broadcast, and UE 1 transmits the first request message to UE 2, UE 3, UE 4 and UE 5. Petition 870250086482, dated 09 / 24 / 2025, page 34 / 169 27 / 61

[00115] In some modes, the first request message includes at least one of:

[00116] first indication of information indicating whether a COT request function is enabled;

[00117] second indication of information indicating a priority of access to the first channel;

[00118] third indication of information indicating a displacement duration in the time domain between a first pre-selected resource and information from the first request message;

[00119] fourth indication of information indicating an index of a first set of resource blocks; or

[00120] fifth indication information indicating a requested quantity of COTs.

[00121] With respect to a method for indicating first indication information, the present disclosure does not impose a limitation on this aspect. By way of example, the indication information may indicate whether the terminal device has activated the COT request function by means of a bit 1. For example, a bit value of 1 indicates that the terminal device has activated the COT request function; a bit value of 0 indicates that the terminal device has not activated the COT request function. By way of example, the first indication information may indicate whether the terminal device has activated the COT request function by means of a designated field. For example, the designated field being carried by the first request message indicates that the terminal device has activated the COT request function; the designated field not being carried by the first request message indicates that the terminal device has not activated the COT request function. Petition 870250086482, dated 09 / 24 / 2025, page 35 / 169 28 / 61

[00122] The COT request function is a function for requesting COT sharing from other terminal devices. Enabling the COT request function indicates that the terminal device has the function to request that other terminal devices share their COTs. Disabling the COT request indicates that the terminal device does not have the function to request that other terminal devices share their COTs.

[00123] The first channel access priority can be used to determine the channel access priority for the type 1 LBT procedure initiated by the terminal device that receives the first request message. In some embodiments, the first channel access priority is less than or equal to the channel access priority corresponding to the first SL data available on the logical channel of the terminal device that transmits the first request message. In other words, a first channel access priority value can be greater than or equal to a channel priority value corresponding to the first SL data available on the logical channel of the terminal device that transmits the first request message.For example, the priority of the first channel may be the same as the access priority of the channel corresponding to the first SL data available on the logical channel of the terminal device transmitting the first request message (i.e., the value of the first channel priority may be equal to the value of the access priority of the channel corresponding to the first SL data available on the logical channel of the terminal device transmitting the first request message). Alternatively, the priority of the first channel may be less than... Petition 870250086482, dated 09 / 24 / 2025, p. 36 / 169 29 / 61 that the priority of access to the channel corresponding to the first SL data available on the logical channel of the terminal device transmitting the first request message (i.e., the priority value of the first channel is less than the priority value of access to the channel corresponding to the first SL data available on the logical channel of the terminal transmitting the first request message).

[00124] In some modes, the first channel access priority value is a random value.

[00125] In some modes, the first channel access priority is set to a default value. For example, the first channel access priority value is 4 by default.

[00126] A first pre-selected resource is a transmission resource corresponding to the first SL data in the logical channel of the terminal device, i.e., the terminal device has completed a resource selection process, and the first SL data in the logical channel of the terminal device has a corresponding SL grant, therefore, the terminal device can determine a position in the PSCCH / PSSCH time-frequency domain based on the SL data for transmission.

[00127] A time-domain offset duration between the first pre-selected resource and the transmission of the first request message may refer to the time-domain offset duration between the start time of the first pre-selected resource in the time domain and the start time of the transmission of the first request message, and the time-domain offset duration may also be Petition 870250086482, dated 09 / 24 / 2025, page 37 / 169 30 / 61 refers to the duration of the offset between a first partition of the first pre-selected resource and a first partition of the transmission of the first request message.

[00128] In some modes, the number of COT requests can be 1 and also be greater than 1, which is not limited in the present disclosure.

[00129] In some embodiments, a channel access mechanism for transmitting the first request message is a type 1 channel access mechanism or a type 2 channel access mechanism.

[00130] In technical solutions according to the embodiments of the present disclosure, when transmitting an initial request message, a terminal device may request the sharing of COTs from other terminal devices, such that the terminal device implements a type 2 channel access mechanism for the shared COT instead of implementing a type 1 channel access mechanism. In this case, a channel detection operation to perform the type 1 channel access mechanism is not required, and thus the power consumption of the terminal device is reduced.

[00131] With regard to the method for transmitting the first solicitation message, illustrative examples are also provided in the embodiments of the present disclosure.

[00132] In some modes, the first request message may be transmitted separately or may be transmitted simultaneously with the second SL data.

[00133] In some modes, the first request message is transmitted separately.

[00134] The term transmitted separately Petition 870250086482, dated 09 / 24 / 2025, page 38 / 169 31 / 61 means that the first request message is not transmitted simultaneously with the SL data, that is, the first request message is not located in the same partition as the SL data.

[00135] For example, illustrated by Figure 12, the first request message is transmitted before the SL data transmission.

[00136] If the first request message is transmitted separately, the first request message includes at least one of the following:

[00137] first indication of information indicating whether a COT request function is enabled;

[00138] second indication of information indicating a priority of access to the first channel;

[00139] third indication of information indicating a displacement duration in the time domain between a first pre-selected resource and the transmission of the first request message;

[00140] fourth indication of information indicating an index of a first set of resource blocks; or

[00141] fifth indication information indicating a requested quantity of COTs.

[00142] In some modes, in a case where the first request message is transmitted separately, the first request message receives the highest priority for access to the channel.

[00143] For example, the priority of access to the channel for the first request message is 1.

[00144] In some modes, the first request message and the second SL data are Petition 870250086482, dated 09 / 24 / 2025, page 39 / 169 32 / 61 transmitted simultaneously.

[00145] After successful access to the channel via channel type 1 or type 2 access, the terminal device transmits the first request message at the same time as transmitting the SL data, i.e., the first request message and the SL data are placed in the same partition.

[00146] In some modes, the first SL data and the second SL data refer to SL data corresponding to different SL transmissions.

[00147] For example, the first SL data and the second SL data may be the SL data corresponding to an initial transmission or the SL data corresponding to a retransmission; they may also be the SL data corresponding, respectively, to two retransmissions.

[00148] It should be clarified that the terms first and second are used only to differentiate SL data. The term first lateral link data is defined as lateral link data intended for transmission, where a transmission resource for the data has not yet been determined by an LBT procedure. The term second lateral link data is defined as lateral link data for which a transmission resource has been determined by an LBT procedure.

[00149] For example, as illustrated in Figure 13, the first request message is transmitted simultaneously with the second SL data.

[00150] In the case where the first request message and the data from the second SL are transmitted simultaneously, the first request message includes Petition 870250086482, dated 09 / 24 / 2025, p. 40 / 169 33 / 61 at least one of the following:

[00151] the first indication showing whether the COT request function is enabled; or

[00152] Second indication information indicating the first priority of access to the channel.

[00153] In some modes, the access priority to the channel corresponding to the first request message and the access priority to the channel corresponding to the first SL data are the same.

[00154] In some embodiments, in a case where the first SL data available on the logical channel of the terminal device is already associated with a corresponding SL grant, the first request message may be transmitted separately or may be transmitted simultaneously with the data from the second side link.

[00155] Upon granting of SL, i.e., upon completion of the resource selection process, the terminal device can determine the position in the PSCCH / PSSCH time-frequency domain for SL data transmission. For example, as illustrated in Figure 14, the resource for SL data transmission is determined and the terminal device can determine the positions in the PSCCH / PSSCH time and frequency domains for SL transmission.

[00156] In some embodiments, in a case where the first SL data available on the logical channel of the terminal device has not yet obtained the corresponding SL grant, the first request message is transmitted separately.

[00157] In some modes, the terminal device may complete the resource selection process with Petition 870250086482, dated 09 / 24 / 2025, page 41 / 169 34 / 61 based on the assistance of a received shareable COT. For example, determining the time domain in which the resource for transmitting SL data available on the logical channel of the terminal transmission device is positioned based on the partition belonging to the shareable COT.

[00158] In some modalities, after step 1110, the method also includes step 1120.

[00159] Step 1120, detect, by the terminal device, the first request message corresponding to a first reply message within a first time range where the first reply message indicates or confirms that the terminal device is permitted to transmit subsequent SL data by the type 2 channel access mechanism.

[00160] The first time range can be preconfigured, can be predefined, or can be determined based on the implementation of the terminal device, which is not limited in the present disclosure.

[00161] In some embodiments, the first reply message includes information that identifies a shareable COT designated for the terminal device.

[00162] In some embodiments, the first SL data available on the logical channel of the terminal device already has the corresponding SL grant. A time unit of the start of the first timeband is a time unit when the first request message is transmitted; or the time unit of the start of the first timeband follows the time unit when the first request message is transmitted, and an interval between the time unit of the start of the first timeband and the time unit when the Petition 870250086482, dated 09 / 24 / 2025, p. 42 / 169 35 / 61 The time the first request message is transmitted is referred to as the first offset duration. The final time unit of the first time band is the time unit in which the first transmission by SL occurs; or the final time unit of the first time band precedes the time unit in which the first transmission by SL occurs, and the interval between the final time unit of the first time band and the time unit in which the first transmission by SL occurs is referred to as the second offset duration. The first transmission by SL follows the transmission of the first request message and is the SL temporally closest to the transmission of the first request message.

[00163] As illustrated in Figure 14, the first time range is (t1+T1, t2-T2), where t1 is the time unit of the first request message, t2 is the time unit in which the first transmission by SL occurs (retransmission 1), T1 is the first displacement duration, and T2 is the second displacement duration. For example, T1 is greater than 0. For example, T1 is greater than or equal to 0. For example, T2 is greater than 0. For example, T2 is greater than or equal to 0.

[00164] In a case where T1 is 0, the starting time unit of the first timeband is the time unit when the first request message is transmitted. In a case where T2 is 0, the ending time unit of the first timeband is the time unit when the first transmission by SL occurs.

[00165] In some modes, the duration of the first displacement and the duration of the second displacement can be configured by the network, or they can be pre-configured, or Petition 870250086482, dated 09 / 24 / 2025, page 43 / 169 36 / 61 may depend on the terminal device implementation, and may be predefined, which is not limited in the present disclosure.

[00166] In some embodiments, the first SL data available on the terminal device's logical channel already has the corresponding SL grant. The start time unit of the first timeband is the time unit when the first request message is transmitted, or the start time unit of the first timeband follows the time unit when the first request message is transmitted, and an interval between the start time unit of the first timeband and the time unit when the first request message is transmitted is called a first offset duration. The end time unit of the first timeband follows the time unit of the first request message, and the interval between the end time unit of the first timeband and the time of the first request message is called the fourth offset, and the duration of the fourth offset is greater than the duration of the first offset.

[00167] As illustrated in Figure 14, the first time range is (t1+T1, t1+T5), where t1 is the time unit of the first request message, T1 is the first offset duration, and T5 is the fourth offset duration. For example, T1 is greater than 0 and T1 is greater than or equal to 0. For example, T5 is greater than 0 and T5 is optimal to or equal to T1.

[00168] In a case where T1 is 0, the initial unit of the first time range is the time unit when the first request message is transmitted. Petition 870250086482, dated 09 / 24 / 2025, page 44 / 169 37 / 61

[00169] In some embodiments, the duration of the first displacement and the duration of the fourth displacement may be configured by the network, or may be pre-configured, or may depend on the implementation of the terminal device, or may be predefined, which is not limited to the present disclosure.

[00170] In some modalities, the time unit mentioned refers to the partition.

[00171] From the transmission of the first request message until the other terminal devices receive the first request message and transmit the first response message to the terminal that transmits the first request message, this process has a certain latency, therefore, the detection of the first response message may be performed again after the transmission of the first request message.

[00172] In some embodiments, upon receiving the first request message, in a case where the other terminal devices have a shareable COT, the other terminal devices transmit the first reply message to the terminal device that transmits the first request message.

[00173] In some embodiments, upon receiving the first request message, in a case where the terminal devices do not have a shareable COT, the other terminal devices execute the type 1 LBT procedure based on the first request message and, upon acquiring the shareable COT, the other terminal devices transmit the first response message to the terminal device that transmits the first request message. For example, the Petition 870250086482, dated 09 / 24 / 2025, p. 45 / 169 38 / 61 LBT type 1 procedure is performed based on the first channel access priority included in the first request message.

[00174] With respect to the first offset duration value, the present disclosure does not impose a limit on this aspect. For example, the duration of the first offset can be determined by referring to a transmission latency between the terminal device transmitting the first request message and the other terminal device.

[00175] In some modalities, the method also includes step 1130.

[00176] Step 1130, in a case where the first reply message is detected within the first time range, the terminal device transmits subsequent SL data via the type 2 channel access mechanism based on the first request message; or, in a case where the first reply message is not detected within the first time range, the terminal device discards the last transmission temporally closest to the first request message, or uses the type 1 channel access mechanism to perform channel access, or triggers channel resource re-selection.

[00177] In some embodiments, in a case where the first reply message is detected within the first time range, the terminal device executes the LBT type 2 procedure based on the first request message, used for one or more SL transmissions of subsequent transmissions. For example, used to perform the first SL transmission. Petition 870250086482, dated 09 / 24 / 2025, p. 46 / 169 39 / 61

[00178] In some embodiments, in a case where the first reply message is not detected within the first time range, the terminal device executes the LBT type 1 procedure to acquire the COT required for SL data transmission.

[00179] In some embodiments, the second offset duration is greater than or equal to the duration required for the type 1 channel access mechanism used by the terminal device to access the channel. In some embodiments, the second offset duration can be determined by referring to the duration required for the type 1 LBT procedure. For example, the second offset duration is greater than or equal to the required duration of the type 1 LBT procedure performed by the terminal device; thus, the terminal device can perform the type 1 LBT procedure if the first reply message is not detected within the first time range.

[00180] In some embodiments, the interval between the final time unit of the first timeband and the time unit when the first SL transmission occurs is greater than or equal to the required duration of the type 1 channel access mechanism executed by the terminal device for channel access. The interval between the final time unit of the first timeband and the time unit when the first SL transmission occurs refers to the length of the interval between the final time unit of the first timeband and the time unit when the first SL transmission occurs.

[00181] In some modalities, the duration of the fourth displacement can be determined by referring to the required duration of the type 1 LBT procedure performed by Petition 870250086482, dated 09 / 24 / 2025, page 47 / 169 40 / 61 terminal device. For example, the interval between the final time unit of the first time band and the time unit in which the first SL transmission occurs is greater than or equal to the required duration of the type 1 LBT procedure performed by the terminal device; thus, the terminal device can execute the type 1 LBT procedure in the case where the first reply message is not detected within the first time band.

[00182] An interval of the duration of the second displacement mentioned above and an interval of the interval between the final time unit of the first time band and the time unit when the first SL transmission occurs are the same interval.

[00183] In some modes, in a case where the first reply message is not detected within the first time range, the terminal device discards the SL transmission temporally closest to the transmission of the first request message. As illustrated in Figure 14, the terminal device discards the first SL transmission.

[00184] In some modes, in a case where the first reply message is not detected within the first time range, the terminal triggers resource re-selection to select a new resource for SL transmission that is temporally closest to the transmission of the first request message.

[00185] In some modes, steps 1120 and 1130 mentioned above are performed again after resource re-selection to acquire a shareable COT used for SL transmission temporally closest to Petition 870250086482, dated 09 / 24 / 2025, page 48 / 169 41 / 61 transmission of the first request message.

[00186] By the above method, the terminal device acquires a shareable COT in a scenario where the SL data available on the terminal device's logical channel is already associated with the corresponding SL grant, so that power consumption is reduced.

[00187] In some embodiments, the SL data available on the logical channel of the terminal device is not yet associated with the corresponding SL grant. The time unit of the first timeband start is the time unit in which the first request message is transmitted; or, the time unit of the first timeband start follows the time unit when the first request message is transmitted, and the interval between the time unit of the first timeband start and the time unit when the first request message is transmitted is termed a third offset duration. A length of the first timeband is called the first duration.

[00188] Illustratively, in Figure 15, the starting time unit of the first time range is (t1+T3), the first duration is T4. Where t1 is the time unit in which the first request message is transmitted, and T3 is the third offset duration. For example, T3 is greater than 0. For example, T3 is greater than or equal to 0. For example, T4 is greater than 0.

[00189] In a case where T3 is 0, the start time unit of the first time band is the time unit when the first request message is transmitted.

[00190] In some modalities, the third duration Petition 870250086482, dated 09 / 24 / 2025, p. 49 / 169 42 / 61 offset can be configured by the network, or it can be pre-configured, or it can depend on the implementation of the terminal device, or it can be predefined, which is not limited in the present disclosure.

[00191] In some embodiments, the initial duration may be configured by the network, or may be pre-configured, or may depend on the implementation of the terminal device, or may be predefined, which is not limited to the present disclosure.

[00192] In some modalities, the unit of time may refer to a partition.

[00193] In some embodiments, upon receiving the first request message, in a case where the other terminal devices have a shareable COT, each of the other terminal devices transmits a first reply message to the terminal device that transmits the first request message.

[00194] In some embodiments, upon receiving the first request message, in the case where the other terminal devices do not have a shareable COT, each of the other terminal devices executes the type 1 LBT procedure based on the first request message; and upon acquiring a shareable COT, each of the other terminal devices transmits a first response message to the terminal device that transmits the first request message. For example, the type 1 LBT procedure is performed based on the first channel access priority included in the first request message.

[00195] This disclosure does not impose a limitation on the value or duration of the third compensation. Petition 870250086482, dated 09 / 24 / 2025, page 50 / 169 43 / 61 For example, the duration of the third shift can be determined by referring to the transmission latency between the terminal transmitting the first request message and the other terminal devices.

[00196] In some forms, the method additionally includes step 1140.

[00197] In step 1140, in a case where the first reply message is detected within the first time range, the terminal device performs resource selection based on the first reply message; or, in a case where the first reply message is not detected within the first time range, the terminal device transmits the first request message again after the first time range.

[00198] In some embodiments, in a case where the first reply message is detected within the first time range, the terminal device performs resource selection based on the first reply message. For example, the first reply message includes information that identifies a shareable COT, and the terminal device randomly selects a resource within the shareable COT.

[00199] In some embodiments, in a case where the first reply message is not detected within the first time frame, the terminal device transmits the first request message again after the first time frame. Illustratively, in Figure 15, the first request message is transmitted again after the first time frame.

[00200] In some modalities, a number of Petition 870250086482, dated 09 / 24 / 2025, page 51 / 169 44 / 61 continuous transmissions of the first request message by the terminal device do not exceed a fourth limit. The specific value of the fourth limit is not specifically limited in the present disclosure.

[00201] A continuous transmission of the first request message refers to not performing SL transmission between two first request transmissions.

[00202] The fourth threshold can be configured by the network, or it can be pre-configured, or it can depend on the implementation of the terminal device, or it can be predefined, which is not limited in the present disclosure.

[00203] By the above method, the terminal device acquires a shareable COT in a scenario where the SL data available on the terminal device's logical channel is not yet associated with the corresponding SL grant, so that power consumption is reduced.

[00204] With regard to steps 1120 to 1140, the present development also provided several alternative solutions.

[00205] In the above modes, the other terminal devices return the first reply message only to the terminal device, where the first reply message indicates or confirms that the terminal device is authorized to transmit subsequent SL data through the type 2 channel access mechanism.

[00206] In some embodiments, the other terminal devices may also send back a second reply message to the terminal device, where the second reply message indicates or confirms that the terminal device is not permitted to transmit SL data. Petition 870250086482, dated 09 / 24 / 2025, p. 52 / 169 45 / 61 subsequent through the type 2 channel access mechanism.

[00207] In some embodiments, at step 1120, the terminal device detects a reply message associated with the first request message, the reply message including a first reply message and a second reply message, wherein the first reply message indicates or confirms that the terminal device is permitted to transmit subsequent SL data via the type 2 channel access mechanism.

[00208] In some embodiments, for step 1130, in a case where the first SL data available on the logical channel of the terminal device already has the associated SL grant, the following scenarios apply.

[00209] In some modes, the first request message is transmitted by point-to-point broadcast. In this case, where the first reply message is not detected within the first time frame, it includes: no reply message is detected within the first time frame; the second reply message is detected within the first time frame while the first reply message is not detected.

[00210] In some embodiments, in a case where the second reply message is detected within the first time range, the terminal device discards the SL transmission temporally closest to the first request message, or performs channel access using the type 1 channel access mechanism, or triggers resource re-selection.

[00211] In some modes, the first reply message is transmitted by means of group broadcasting or broadcasting. In these cases, where the first message of Petition 870250086482, dated 09 / 24 / 2025, p. 53 / 169 46 / 61 response not detected within the first time frame includes: no response message is detected within the first time frame; the second response message is detected within the first time frame while the first response message is not detected.

[00212] In some embodiments, in a case where the second reply message is detected within the first time slot, the terminal device continues to detect the reply message associated with the first request message within the first time slot until the first reply message is detected, and the terminal device transmits subsequent SL data via the type 2 channel access mechanism based on the first reply message.

[00213] In some embodiments, in a case where the second reply message is detected within the time range while the first reply message is not detected, the terminal device discards the SL transmission temporally closest to the transmission of the first request message, or performs channel access using the type 1 channel access mechanism, or triggers resource re-selection.

[00214] In some embodiments, in a case where the second reply message is detected within the first time range, the terminal discards the SL transmission temporally closest to the transmission of the first request message, or performs channel access using the type 1 channel access mechanism, or triggers resource re-selection.

[00215] In some embodiments, the first SL data available on the logical channel of the terminal device is not yet associated with the corresponding SL grant, there Petition 870250086482, dated 09 / 24 / 2025, page 54 / 169 47 / 61 the following scenarios in relation to stage 1140.

[00216] In some modes, the first request message is transmitted by point-to-point broadcast. In this case, the first reply message is not detected within the first time frame, which includes: no reply message is detected within the first time frame; the second reply message is detected within the first time frame while the first reply message is not detected.

[00217] In some embodiments, in a case where the second reply message is detected within the first time frame, the terminal device transmits the first request message again within the first time frame.

[00218] In some modes, the first request message is transmitted by group broadcast or broadcast. In these cases, the first request message not being detected within the first time frame includes: no response message is detected within the first time frame; the second response message is detected within the first time frame while the first response message is not detected.

[00219] In some embodiments, the second reply message is detected within the first time frame, the terminal device continues to detect the reply message associated with the first request message within the first time frame until the first reply message is detected, and the terminal device performs resource selection based on the first reply message.

[00220] In some modes, the second message Petition 870250086482, dated 09 / 24 / 2025, page 55 / 169 Response 48 / 61 is detected within the first time slot, while the first response is not detected, and the terminal device transmits the first request message again within the first time slot.

[00221] In some modes, the second reply message is detected within the first time slot, and the terminal device transmits the first request message again within the first time slot.

[00222] The technical solutions according to the embodiments of the present disclosure offer alternative solutions based on different cases while detecting the first response message within the first time range. This is to help the terminal device acquire a shareable COT from other terminal devices to reduce power consumption.

[00223] The following describes in detail the apparatus embodiments of the present disclosure, which can be used to implement the method embodiments of the present disclosure. For details not disclosed in the apparatus embodiments, reference may be made to the method embodiments of the present disclosure.

[00224] With reference to Figure 16, a block diagram of an apparatus for transmitting request messages is illustrated according to some embodiments of the present disclosure. The apparatus has the request message transmission function described in the embodiments of the method above; the function can be implemented via hardware or via hardware running associated software. The apparatus can be the terminal device mentioned above, or it can be configured within the terminal device. As illustrated in Figure Petition 870250086482, dated 09 / 24 / 2025, page 56 / 169 49 / 61 16, the device may include: a 1610 transmission module.

[00225] The 1610 transmission module is configured to transmit a first request message, where the first request message is used to request COT sharing from at least one other terminal device.

[00226] In some embodiments, the terminal device transmits the first request message in the case where a first condition is met, the first condition including at least one of the following:

[00227] the terminal device being a reduced capacity terminal device;

[00228] the first SL data available on a logical channel of the terminal device;

[00229] a value of a channel access priority corresponding to the first SL data in the logical channel of the terminal device being greater than or equal to a first limit;

[00230] a value of a containment window corresponding to the first SL data in the logical channel of the terminal device being greater than or equal to a second limit; or

[00231] A value of a random withdrawal counter in a type 1 channel access mechanism corresponding to the first SL data available on the terminal device's logical channel being greater than or equal to a third limit.

[00232] In some modes, the first request message includes at least one of:

[00233] first indication of information that Petition 870250086482, dated 09 / 24 / 2025, page 57 / 169 50 / 61 indicate whether a COT request function is enabled;

[00234] second indication of information indicating a priority of access to the first channel;

[00235] third indication of information indicating a displacement duration in the time domain between a first pre-selected resource and the transmission of the first request message;

[00236] fourth indication of information indicating an index of a first set of resource blocks; or

[00237] fifth indication information indicating a quantity of COTs requested.

[00238] In some embodiments, the first request message is carried by means of SL control information (SCI), or carried by means of a medium access control (MAC) element (CE).

[00239] In some modes, the resource for transmitting the first request message is allocated by the network device or selected by the terminal device.

[00240] In some modes, the first request message is transmitted via any of the following options: point-to-point broadcast, group broadcast, or broadcast.

[00241] In some embodiments, a channel access mechanism for the first request message is a type 1 channel access mechanism or a type 2 channel access mechanism.

[00242] In some embodiments, as illustrated in Figure 17, the 1600 device also includes: a 1620 processing module.

[00243] The 1620 processing module is Petition 870250086482, dated 09 / 24 / 2025, page 58 / 169 51 / 61 is configured to detect a first reply message associated with the first request message within a first time range, where the first reply message indicates or confirms that the terminal device is permitted to transmit subsequent SL data through the type 2 channel access mechanism.

[00244] In some embodiments, the SL data available on the logical channel of the terminal device is already associated with a corresponding SL grant;

[00245] A first timeband start time unit is the time unit in which the first request message is transmitted; or the first timeband start time unit follows the time unit when the first request message is transmitted, and the interval between the first timeband start time unit and the time unit when the first request message is transmitted is called the first offset duration;

[00246] A final time unit of the first time band is the time unit that contains a first SL transmission; or the final time unit of the first time band precedes the time unit when the first SL transmission occurs, and the interval between the final time unit of the first time band and the time unit when the first SL transmission occurs is termed the second offset duration. The first SL transmission follows the transmission of the first request message and is the SL transmission temporally closest to the transmission of the first request message.

[00247] In some modes, the second travel time is greater than or equal to the time required for Petition 870250086482, dated 09 / 24 / 2025, page 59 / 169 52 / 61 the type 1 channel access mechanism used by the terminal device to access the channel.

[00248] In some embodiments, the first SL data available on the logical channel of the terminal device is already associated with the corresponding SL grant.

[00249] The time unit of the first time lane start is the time unit in which the first request message is transmitted; or the time unit of the first time lane start follows the time unit in which the first request message is transmitted, and an interval between the time unit of the first time lane start and the time unit in which the first request message is transmitted is called the first offset duration;

[00250] The final time unit of the first time band follows the time unit when the first request message is transmitted, and an interval between the time unit when the first request message is transmitted and the final time unit of the first time band is called the fourth offset duration, wherein the fourth offset duration is greater than the duration of the first offset.

[00251] The final time unit precedes the time unit when the first SL transmission is performed; and / or the interval between the final time unit and the time unit when the first SL transmission is performed is greater than or equal to the duration required for the terminal device to access the channel using a type 1 channel access mechanism, where the first SL transmission is an SL transmission that follows the transmission of the first request message and is temporally closer to the transmission. Petition 870250086482, dated 09 / 24 / 2025, pp. 60 / 169 53 / 61 of the first request message.

[00252] In some embodiments, the first SL data available on a logical channel of the terminal device is not yet associated with a corresponding SL grant.

[00253] A time unit of the first time band is a time unit when the first request message is transmitted or follows the time unit when the first request message is transmitted, wherein an interval between the time unit when the first request message is transmitted and the time unit of the first time band is termed as a third offset duration;

[00254] A length of the first time strip is called the first duration.

[00255] In some embodiments, the 1620 processing module is additionally configured to transmit, in a case where the first reply message is detected within a first time interval, subsequent SL data based on the first reply message using a type 2 channel access mechanism; or the 1620 processing module is additionally configured to discard, in a case where the first reply message is not detected within the first time range, the SL transmission temporally closest to the transmission of the first request message, or to perform channel access using a type 1 channel access mechanism, or to trigger resource re-selection.

[00256] In some embodiments, the 1620 processing module is additionally configured for Petition 870250086482, dated 09 / 24 / 2025, pp. 61 / 169 54 / 61 select, in a case where the first request message is detected within the first time range, a resource based on the first response message; or, processing module 1620 is additionally configured to retransmit, in a case where the first response message is not detected within the first time range, the first request message subsequent to the first time range.

[00257] In some modes, the first request message is transmitted separately; or the first request message and the second SL data are transmitted simultaneously.

[00258] In some modes, in a case where the first request message is transmitted separately, the first request message receives the highest priority for access to the channel.

[00259] In technical solutions according to the embodiments of the present disclosure, when transmitting an initial request message, a terminal device may request the sharing of COTs from other terminal devices, such that the terminal device implements a type 2 channel access mechanism for the shared COT instead of implementing a type 1 channel access mechanism. In this case, a channel detection operation to perform the type 1 channel access mechanism is not required, and thus the power consumption of the terminal device is reduced.

[00260] It should be noted that the device, according to the embodiments of the present disclosure, implements its functionality solely on the basis of the division of functional modules, for example. In practice, the functions Petition 870250086482, dated 09 / 24 / 2025, p. 62 / 169 The functions described in items 55 / 61 can be assigned to different modules as needed; that is, the internal structure of a device can be divided into different functional modules to perform all or part of the functionalities mentioned above.

[00261] With regard to the apparatus described in the embodiments above, the specific operations performed by each module have already been described in detail in the corresponding method embodiments of this disclosure, which are not elaborated in this document.

[00262] With reference to Figure 18, a schematic structural diagram of a terminal device according to some embodiments of the present disclosure. The terminal device 1800 may include: a processor 1801, a transceiver 1802, and a memory 1803. The processor 1801 is configured to perform the function of the processing module 1620, and the transceiver 1802 is configured to perform the function of the transmission module 1610.

[00263] The 1801 processor includes one or multiple processing cores and performs various functional applications and information processing by executing software programs and modules. The 1801 processor is configured to execute all the steps performed by the terminal device in the modes of the above method, except for the transmission and reception steps.

[00264] The 1802 transceiver may include a receiver and a transmitter. For example, the receiver and transmitter may be implemented as a single wireless communication unit, in which the wireless communication unit may include a wireless communication chip and a radio frequency antenna. The 1802 transceiver is configured to Petition 870250086482, dated 09 / 24 / 2025, pp. 63 / 169 56 / 61 execute the transmission and / or reception steps performed by the terminal device in the modes of the method above.

[00265] Memory 1803 can be communicatively connected to processor 1801 and transceiver 1802.

[00266] Memory 1803 can be configured to store one or more computer programs that can be loaded and executed by the processor. Processor 1801 is configured to load and execute one or more computer programs to perform all steps in the above method modes.

[00267] In addition, memory can be implemented using various types of transient or non-transient storage devices, or a combination thereof, including, but not limited to: a magnetic or optical disk, an electrically erasable programmable read-only memory (EEPROM), an erasable programmable read-only memory (EPROM), a static random access memory (SRAM), a read-only memory (ROM), a magnetic storage device, a flash memory, and a programmable read-only memory (PROM).

[00268] In some embodiments, the 1802 transceiver is configured to transmit the first request message, where the first request message is used to request COT sharing from at least one other terminal device.

[00269] For details not disclosed in the modalities, reference may be made to the modalities of the present disclosure above, which are not prepared in this document.

[00270] Some modalities of the present disclosure Petition 870250086482, dated 09 / 24 / 2025, p. 64 / 169 57 / 61 additionally provide a computer-readable storage medium used to store computer programs, which, when executed by a processor, performs the above method to transmit a request message. In some embodiments, the storage medium may include: a read-only memory, a random access memory (RAM), a solid-state drive (SSD), or something similar to an optical disc. Random access memories may include: a resistive random access memory (ReRAM) or a dynamic random access memory (DRAM).

[00271] Some embodiments of the present disclosure additionally provide a chip. The chip includes programmable electrical circuits and / or one or more program instructions. The chip is configured to load and execute one or more program instructions to perform the request message transmission method in the method embodiments above.

[00272] Some embodiments of the present disclosure additionally provide a computer program product. The computer program product includes one or more computer programs stored on a computer-readable storage medium, wherein the computer program(s), when loaded and executed by a processor, cause the processor to execute the method for transmitting request messages in the implementations of the above method.

[00273] It should be understood that the term indication mentioned in the modalities of the present disclosure is a direct indication, an indirect indication, or an indication that an associative relationship exists. For example, A indicates B, which may mean that A indicates B directly, for example, B can be acquired by A, or that A indicates B indirectly, Petition 870250086482, dated 09 / 24 / 2025, pp. 65 / 169 58 / 61 for example, A indicates C, through which B can be acquired, or that there is an associative relationship between A and B.

[00274] In the description of the modalities of the present disclosure, the term correspond indicates a direct or indirect relationship of correspondence between two items, or indicates a relationship of association between two items; and also indicates relationships such as to indicate and to be indicated, or to configure and to be configured.

[00275] In some embodiments of the present disclosure, the term default is implemented by pre-storing corresponding codes, tables, or other means that can be defined to indicate related messages in devices (including, for example, terminal devices and network devices), and the present disclosure does not limit the specific implementation thereof. For example, the term default refers to being defined in a protocol.

[00276] In some embodiments of the present disclosure, the term protocol refers to a standard protocol in the field of communication, including, for example, the LTE protocol, the NR protocol, and related protocols applied in future communication systems, which is not limited to the present disclosure.

[00277] The term "a plurality of" mentioned in this document means two or more. The term "and / or" describes the association relationship between the associated objects and indicates that three relationships may be present. For example, the expression "A and / or B" means (A), (B) or (A and B). The symbol / usually indicates an "or" relationship between the associated objects. Petition 870250086482, dated 09 / 24 / 2025, pp. 66 / 169 59 / 61

[00278] References in this document to greater than or equal to may indicate greater than or equal to or simply greater than, and less than or equal to may indicate less than or equal to or simply less than.

[00279] Furthermore, the serial numbers of the processes described in this document only show a possible illustrative sequence of execution of the processes. In some other embodiments, the processes may also be performed out of the numbering sequence, for example, two processes with different serial numbers are performed simultaneously, or two processes with different serial numbers are performed in reverse order of the illustrated sequence, which is not limited to the present disclosure.

[00280] Persons skilled in the art should understand that, in one or more of the above embodiments, the functions described in the embodiments of this disclosure may be implemented in hardware, software, firmware, or any combination thereof. The functions, when implemented in software, may be stored on a computer-readable medium or transmitted as one or more instructions or codes on a computer-readable medium. Computer-readable medium includes computer storage medium and communication medium, where communication medium includes any media that facilitates the transfer of a computer program from one place to another. Storage medium is any available media that is accessible by a general-purpose or specialized computer.

[00281] The preceding description is provided to enable anyone skilled in the art to practice the various aspects described in this document. Several Petition 870250086482, dated 09 / 24 / 2025, pp. 67 / 169 60 / 61 Modifications in these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be encompassed by the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean one and only one, unless specifically indicated, but rather one or more. Unless specifically indicated otherwise, the term "some" refers to one or more. Combinations such as at least one of A, B or C, at least one of A, B and C and A, B, C or any combination thereof include any combination of A, B and / or C and may include multiples of A, multiples of B or multiples of C.Specifically, combinations such as at least one of A, B, or C, at least one of A, B, and C, and A, B, and C, or any combination thereof, may be only A, only B, only C, A and B, A and C, B and C, or A and B and C, where any of these combinations may contain one or more members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or may hereafter become known to those skilled in the art are expressly incorporated herein by reference and shall be covered by the claims. Furthermore, nothing disclosed herein is intended to be made available to the public, regardless of whether such disclosure is explicitly mentioned in the claims. No element of a claim shall be construed as a means plus function unless such element is expressly stated. Petition 870250086482, dated 09 / 24 / 2025, pp. 68 / 169 61 / 61 mentioned using the phrase "means to".

[00282] The above are merely illustrative examples of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, enhancements and the like, made within the principles of the present disclosure, shall be within the scope of protection of the present disclosure. Petition 870250086482, dated 09 / 24 / 2025, pp. 69 / 169

Claims

1 / 6 CLAIMS 1. METHOD FOR TRANSMITTING A REQUEST MESSAGE, performed by a terminal device, wherein the method is characterized by comprising: transmitting (1110) a first request message, wherein the first request message is used to request the sharing of a channel occupation time, COT, from at least one other terminal device.

2. METHOD, according to claim 1, characterized in that the terminal device transmits the first request message in a case where a first condition is satisfied, wherein the first condition comprises at least one of: the terminal device is a reduced-capacity terminal device; the first side-link data is available on a logical channel of the terminal device; a value of a channel access priority corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a first limit; a value of a contention window corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a second limit; or a value of a random backoff counter in a type 1 channel access mechanism corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a third limit.

3. METHOD, according to claim 1 or 2, Petition 870250086482, dated 09 / 24 / 2025, page 70 / 169 2 / 6 characterized in that the first request message comprises at least one of the following: first indication of information indicating whether a COT request function is activated; second indication of information indicating a priority of access to the first channel; third indication of information indicating a time-domain offset duration between a first pre-selected resource and the transmission of the first request message; fourth indication of information indicating an index of a first set of resource blocks; or fifth indication of information indicating a quantity of COT requested.

4. METHOD, according to any one of claims 1 to 3, characterized in that the first request message is carried by means of side link control information, SCI, or carried by a media access control element, CE, MAC.

5. A METHOD, according to any one of claims 1 to 4, characterized in that a resource for transmitting the first request message is allocated by a network device or selected by the terminal device.

6. METHOD, according to any one of claims 1 to 5, characterized in that the first solicitation message is transmitted by means of any one of: point-to-point broadcasting, group broadcasting or broadcasting.

7. METHOD, according to any one of claims 1 to 6, characterized by the channel access mechanism for the first request message being a type 1 channel access mechanism or a type 2 channel access mechanism.

8. METHOD, according to any one of claims 1 to 7, characterized in that, when transmitting the first request message, the method further comprises: detecting within a first time range, a first reply message corresponding to the first request message, wherein the first reply message indicates or confirms that the terminal device is permitted to transmit subsequent side link data by a type 2 channel access mechanism.

9. METHOD, according to any one of claims 1 to 8, characterized in that the first request message is transmitted separately; or the first request message and the data from the second side link are transmitted simultaneously.

10. APPARATUS FOR TRANSMITTING A REQUEST MESSAGE, wherein the apparatus is characterized by comprising: a transmission module (1610), configured to transmit a first request message, wherein the first request message is configured to request the sharing of a channel occupation time, COT, from at least one other terminal device.

11. APPARATUS, according to claim 10, characterized by the terminal device transmitting, under a first condition, the first request message, being Petition 870250086482, dated 09 / 24 / 2025, page.72 / 169 4 / 6 that the first condition comprises at least one of the following: the terminal device is a reduced-capacity terminal device; the first side-link data is available on a logical channel of the terminal device; a value of a channel access priority corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a first limit; a value of a contention window corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a second limit; or a value of a random backoff counter in a type 1 channel access mechanism corresponding to the first side-link data on the logical channel of the terminal device is greater than or equal to a third limit.

12. APPARATUS, according to claim 10 or 11, characterized in that the first request message comprises at least one of the following: first indication of information indicating whether a COT request function is activated; second indication of information indicating a priority of access to the first channel; third indication of information indicating a time-domain offset duration between a first pre-selected resource and the transmission of the first request message; fourth indication of information indicating an index of a first set of resource blocks; or Petition 870250086482, dated 09 / 24 / 2025, page 73 / 169 5 / 6 fifth indication of information indicating a quantity of COT requested.

13. APPARATUS, according to any one of claims 10 to 12, characterized by further comprising: a processing module (1620), configured to detect a first reply message corresponding to the first request message within a first time range, wherein the first reply message indicates or confirms that the terminal device is permitted to transmit subsequent side link data by a type 2 channel access mechanism.

14. APPARATUS, according to claim 13, characterized in that the first available side-link data on a logical channel of the terminal device is already associated with a corresponding side-link grant; a start time unit of the first timeband being a time unit when the first request message is transmitted; or the start time unit of the first timeband follows the time unit when the first request message is transmitted, and an interval between the time unit when the first request message is transmitted and the start time unit of the first timeband is a first offset duration; and a final time unit of the first timeband being a time unit containing a first side-link transmission; or the final time unit of the first timeband precedes the time unit when the Petition 870250086482, dated 09 / 24 / 2025, p.74 / 169 6 / 6 first side link transmission, and the interval between the time unit when the first side link transmission occurs and the final time unit of the first time band is termed a second offset duration; wherein the first side link transmission follows the transmission of the first request message and is the side link transmission temporally closest to a transmission of the first request message.

15. APPARATUS, according to claim 13 or 14, characterized in that the processing module is further configured to, if a first reply message is detected within a first time interval, transmit subsequent side-link data based on the first reply message by means of a type 2 channel access mechanism; or the processing module is further configured to, if the first reply message is not detected within the first time range, discard a side-link data transmission temporally closer to the transmission of the first request message, or perform channel access using a type 1 channel access mechanism, or trigger resource re-selection. Petition 870250086482, dated 09 / 24 / 2025, pp. 75 / 169

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