Method for resource reservation and indication for relay terminal in vehicle communication

Abstract

A method for resource reservation and indication for a relay terminal in vehicle communication is disclosed. A resource reservation method in vehicle communication according to an embodiment may include the steps of: selecting a plurality of relay terminals by determining whether to perform relaying; and reserving resources to be used by an agent terminal and the selected plurality of relay terminals so that the selected plurality of relay terminals performs relaying by using resources provided from the agent terminal.

Description

Resource Reservation and Instruction Scheme for Relay Terminals in Vehicular Communication

[0001] The following description relates to resource allocation techniques for relay terminals in vehicular communication.

[0002]

[0003] To improve connectivity and safety in modern transportation systems, the 3rd Generation Partnership Project (3GPP) has integrated Vehicle-to-Everything (V2X) communication. V2X communication encompasses a wide range of technologies that enable vehicles to interact effectively with their surroundings. It includes vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), vehicle-to-pedestrian (V2P), and especially vehicle-to-vehicle (V2V) communication. These communication methods form the foundation for realizing a safe and intelligent transportation system (ITS). V2V communication plays a crucial role in enhancing road safety and optimizing traffic flow by enabling vehicles to exchange information directly. This allows vehicles to share real-time awareness of their surroundings, enabling them to proactively detect and respond to potential hazards. Furthermore, by sharing mobility information, vehicles can improve traffic flow, contributing to a more efficient and responsive transportation system.

[0004] In V2V communication, one of the most commonly used messages is the Basic Safety Message (BSM). BSM contains dynamic information, such as the vehicle's current position, speed, and direction of travel. This information is crucial for maintaining a safe distance from surrounding vehicles and improving traffic efficiency. Therefore, reliable transmission of BSM is crucial for V2V communication, and achieving a high Packet Reception Ratio (PRR) within the transmitting vehicle's coverage area is a key indicator.

[0005] An effective way to increase PRR is to optimize resource allocation to minimize interference between transmitting user equipment (UEs). 3GPP has proposed Mode 1 and Mode 2 resource allocation schemes applicable to 5G NR-V2X communications, but each has geographical and performance constraints. However, it should be noted that resource allocation schemes alone have limitations in various channel attenuation factors, such as Non-Line-of-Sight (NLOS) and Non-Line-of-Sight with Vehicles (NLOSv).

[0006] To overcome these issues, using relays is considered a feasible solution. However, utilizing relays presents several significant challenges. First, selecting the most appropriate relay vehicle is a complex task. Strategically positioning vehicles is crucial for improving communication coverage and quality, making optimal vehicle selection essential. Second, determining the required number of relay vehicles is also a critical consideration. Too few relays may not sufficiently extend communication coverage, while excessive relays can lead to unnecessary resource consumption. Third, the transmitting vehicle must instruct the selected relay vehicle to relay and, at the same time, reserve resources for the instructed vehicle in advance and instruct the relay vehicle to do so. This is to prevent performance degradation due to resource conflicts in 5G NR V2X Mode 2 (Autonomous mode).

[0007]

[0008] We propose an efficient resource reservation and instruction method for relaying terminals while complying with the 3GPP V2X communication protocol.

[0009]

[0010] A method for reserving resources in vehicle communication may include: selecting a plurality of relay terminals based on a determination of whether to perform relaying; reserving resources to be used by an agent terminal and the plurality of selected relay terminals so that relaying is performed using resources provided from an agent terminal by the plurality of selected relay terminals; and instructing the plurality of selected relay terminals to use the reserved resources.

[0011] The above-described reserving step includes a step of broadcasting to surrounding vehicles using message information including vehicle identification information related to the plurality of selected relay terminals and a transmission block index for the relay terminal, wherein the surrounding vehicle, upon receiving the message information, if the surrounding vehicle is not a relay terminal, ignores the message information, and if the surrounding vehicle is a relay terminal, relays other message information using resources provided from the agent terminal.

[0012] The above-mentioned reserving step may include a step of reserving resources to be used by the agent terminal and the selected plurality of relay terminals during a sensing window set in the agent terminal, and preempting the reserved resources using a 1st-Sidelink Channel Indicator (SCI).

[0013] The above-mentioned reservation step may include a step of identifying resources preempted by each terminal using a 1st-Sidelink Channel Indicator (SCI) sensed from each terminal of a surrounding vehicle, and selecting an available transmission block by measuring the reception strength of a reference signal in the resources preempted from each terminal.

[0014] The above-described reserving step may include a step of excluding transmission blocks already allocated to each terminal or transmission blocks having a reference signal reception strength exceeding a threshold value.

[0015] The above-mentioned reserving step may include a step of designating the remaining transport blocks as available transport blocks when the remaining transport blocks within the sensing window are greater than or equal to a preset value of the total resources.

[0016] The above-described reserving step may include a step of increasing a reference signal reception strength threshold by a preset value when the remaining transmission blocks within the sensing window are less than a preset value of the entire resource, and then repeating the process of selecting a transmission block that is available again until the transmission block reaches the preset value.

[0017] The above resource reservation method can indicate whether it is a relay terminal through a 1-step SCI or a 2-step SCI, and if the relay terminal is indicated, can decode message information.

[0018] The above-described step may include a step of broadcasting information about the reserved resource to the selected plurality of relay terminals via a 1st or 2nd-Sidelink Channel Indicator (SCI).

[0019] The above-described step may include a step of instructing each terminal to decode message information using a CAM message.

[0020] The above-described step may include a step of instructing to decode the message information using a spare field value of the step 1 or step 2 SCI.

[0021] The above-described step may include a step of instructing the plurality of selected relay terminals to perform relaying through unicast settings.

[0022] The above-mentioned reservation step may include a step of selecting resources for the selected plurality of relay terminals by additionally considering sensing information of surrounding terminals based on the agent terminal.

[0023] The above-described step may include a step of commonly allocating resources to be used by the plurality of selected relay terminals when broadcasting to the plurality of selected relay terminals.

[0024] The resource reservation system may include a terminal selection unit that selects a plurality of relay terminals based on a determination of whether to perform a relay; a resource reservation unit that reserves resources to be used by the agent terminal and the plurality of selected relay terminals so that the plurality of selected relay terminals can perform relaying using resources provided from the agent terminal; and an instruction unit that instructs the plurality of selected relay terminals to use the reserved resources.

[0025]

[0026] It not only complies with the strict protocols specified by 3GPP, but can also improve the PRR performance of the network.

[0027]

[0028] FIG. 1 is a block diagram illustrating the configuration of a resource reservation system in one embodiment.

[0029] FIG. 2 is a flowchart for explaining a resource reservation method in vehicle communication in one embodiment.

[0030] Figure 3 is an example assuming a highway environment in one embodiment.

[0031] FIG. 4 is a diagram for explaining a relay terminal selection and resource allocation method in one embodiment.

[0032] FIG. 5 is a diagram for explaining an operation of selecting a relay terminal in one embodiment.

[0033] FIG. 6 and FIG. 7 are diagrams for explaining SCI (Sidelink Channel Indicator) in one embodiment.

[0034]

[0035] Hereinafter, the detailed description will be given with reference to the attached drawings.

[0036]

[0037] FIG. 1 is a block diagram for explaining the configuration of a resource reservation system in one embodiment, and FIG. 2 is a flowchart for explaining a resource reservation method in vehicle communication in one embodiment.

[0038] The processor of the resource reservation system (100) may include a terminal selection unit (110), a resource reservation unit (120), and a command unit (130). These components of the processor may be representations of different functions performed by the processor according to control commands provided by program codes stored in the resource reservation system. The processor and the components of the processor may control the resource reservation system that performs steps (210 to 230) included in the resource reservation method in vehicle communication of FIG. 2. At this time, the processor and the components of the processor may be implemented to execute instructions according to the code of the operating system included in the memory and the code of at least one program.

[0039] The processor can load program code stored in a program file for a resource reservation method in vehicle communication into memory. For example, when a program is executed in the resource reservation system, the processor can control the resource reservation system to load the program code from the program file into memory under the control of the operating system. At this time, the processor can execute commands of corresponding portions of the program code loaded into the memory in each of the terminal selection unit (110), the resource reservation unit (120), and the instruction unit (130), thereby executing subsequent steps (210 to 230), which may be different functional representations of the processor.

[0040] In step (210), the terminal selection unit (110) may select multiple relay terminals based on whether to perform a relay. The terminal selection unit (110) may select multiple relay terminals using a deep learning model. The terminal selection unit (110) may select the terminal furthest from the agent terminal in the forward or reverse direction within the agent terminal's coverage area as the relay terminal.

[0041] In step (220), the resource reservation unit (120) can reserve resources to be used by the agent terminal and the selected plurality of relay terminals so that the agent terminals can relay using the resources provided by the agent terminals. This allows the relay terminal's resources to be individually allocated to each relay terminal. In addition, the resource reservation unit (120) can select resources for the selected plurality of relay terminals by additionally considering sensing information of surrounding terminals based on the agent terminal. In this way, resource allocation performance can be improved by utilizing inter-UE coordination. The resource reservation unit (120) can broadcast to surrounding vehicles using message information including vehicle identification information related to the selected plurality of relay terminals and a transmission block index for the relay terminal. The resource reservation unit (120) can reserve resources to be used by the agent terminal and the selected plurality of relay terminals during a sensing window set for the agent terminal, and can preempt the reserved resources using a 1st-Sidelink Channel Indicator (SCI). The resource reservation unit (120) can identify resources preemptively occupied by each terminal using the 1st-Sidelink Channel Indicator (SCI) sensed from each terminal of the surrounding vehicles, and select an available transmission block by measuring the reference signal reception strength in the resources preemptively occupied by each terminal. The resource reservation unit (120) can exclude transmission blocks already allocated to each terminal or transmission blocks with a reference signal reception strength exceeding a threshold. The resource reservation unit (120) can designate the remaining transmission blocks as available transmission blocks if the remaining transmission blocks within the sensing window are equal to or greater than a preset value of the entire resources.The resource reservation unit (120) can repeat the process of increasing the reference signal reception strength threshold by a preset value and then selecting a usable transmission block again when the remaining transmission blocks within the sensing window are less than the preset value of the entire resource until the number of transmission blocks reaches the preset value.

[0042] The instruction unit (130) can instruct a plurality of selected relay terminals to use reserved resources. The instruction unit (130) can broadcast information about the reserved resources to the plurality of selected relay terminals through a first- or second-stage SCI (2nd-Sidelink Channel Indicator, SCI). The instruction unit (130) can instruct each terminal to decode message information using application data (e.g., a CAM message, BSM, etc.). The instruction unit (130) can instruct decoding of message information using a free field value of the first- or second-stage SCI. The instruction unit (130) can instruct the plurality of selected relay terminals to perform relaying through a unicast setting. In addition, when the instruction unit (130) broadcasts to the plurality of selected relay terminals, the resources to be used by the plurality of selected relay terminals can be commonly allocated to the selected relay terminals. The instruction unit (130) can transmit identical resources (time / frequency) to relay terminals via the same message. Therefore, a single resource can be allocated regardless of the number of relay terminals. In this case, relay terminals that meet the conditions can perform relaying without having to specify the ID of the relay terminal. The conditions can be determined in advance and, when necessary, can be notified via signaling or control messages.

[0043] Figure 3 is an example assuming a highway environment in one embodiment.

[0044] In this example, we assume a six-lane highway environment where K transmitting user equipment (UEs) share M transport blocks (TBs) among N UEs. The highway lanes are 4 m wide and 2 km long, and vehicles move to the right in the upper three lanes and to the left in the lower three lanes. All vehicles have a speed of 70 km / h, and their positions are updated every 100 ms. When a vehicle crosses the road boundary, it is set to reappear on the opposite side of the same lane, thereby maintaining a constant number of vehicles on the road. There is a UE-type RSU located 150 m from the left side of the highway. We assume that the channel between the RSU and all vehicles is within line-of-sight (LOS).

[0045] Each transmission vehicle k is within the coverage of transmission vehicles N through sensors such as RiDAR / LaDAR. k It is assumed that the transmitting vehicle is aware of the location information of N k Among the vehicles, relay candidate vehicle N c Select relay candidate vehicle N c are spatially uniformly selected within the coverage area of ​​the transmitting vehicle. Each transmitting UE broadcasts a BSM message every 100 ms, and each transmission of a BSM message is assumed to use a single TB. In Fig. 3, K = 2 and N c =3 shows a hypothetical highway scenario. Large-scale attenuation components including path loss and shadowing effects are included. Consider the small damping component By introducing the composite channel gain h, is expressed as a parameter represents a Rayleigh distribution with mean 0 and variance 1. The channel gain between the k-th transmitter and the j-th receiver is h k,j, the signal-to-interference-plus-noise ratio (SINR) received from the jth receiver to the kth transmitter can be expressed as follows.

[0046] Mathematical formula 1:

[0047]

[0048] At this time, represents the noise power, and P Tx is the transmission power. A binary resource selection indicator that uses 1 if the kth and lth transmitters use the mth TB, and 0 otherwise. and In order to measure PRR, SINR threshold is used. Message reception is performed if SINR is It is considered a success when it is equal to or greater than . An indicator that is 1 when one is present, or 0 otherwise Introduce N k Let be the number of vehicles receiving from the kth transmitter in the coverage radius R. PRR of the kth transmitter, PRR k can be expressed as follows.

[0049] Mathematical formula 2:

[0050]

[0051] FIG. 4 is a diagram for explaining a relay terminal selection and resource allocation method in one embodiment.

[0052] In this embodiment, we will describe the operation of inter-vehicle (terminal-to-terminal) relay terminal selection and resource allocation in a situation where there is no base station in vehicle communication. The agent terminal can check whether relay is necessary (410). The agent terminal determines whether the relay performs PRR. eIt can be determined whether the PRR is lower than the required PRR (420). The agent terminal determines whether the PRR e Resource allocation can be performed using 5G-NR mode2 when the PRR is higher than the required PRR. The agent terminal e A relay terminal can be selected if its PRR is lower than the required PRR.

[0053] For example, an agent terminal can select multiple relay terminals using a deep learning model. In the embodiment, a deep reinforcement learning model (DEEP REINFORCEMENT LEARNING MODEL) will be described as an example of a deep learning model. This deep reinforcement learning model is only an example and is not limited thereto. An agent terminal can designate all terminals within its own coverage as relay terminal candidates using the received BSM information (440). An agent terminal can select a relay terminal using MARL among the relay terminal candidates (450).

[0054] More specifically, we examine the Multi-Agent Reinforcement Learning (MARL) model based on Independent Q-Learning (IQL). IQL is a distributed policy-based model in multi-agent reinforcement learning. Each agent trains its network using its own observations, treating other agents as part of the environment. We then consider the case where each agent's DQN adopts a global reward, taking into account the actions of all agents and training accordingly.

[0055] 1) Agent

[0056] K transmitting UEs are modeled as agent terminals, and each agent terminal has N c It consists of a number of virtual agents. Each virtual agent corresponds to a relay candidate UE. Therefore, based on the behavior of the virtual agent, a decision is made as to whether to use the corresponding relay candidate UE as a relay.

[0057] If a k Mark as the kth agent terminal to a k If we denote it as the ith virtual agent, a k It is composed as follows:

[0058] Mathematical formula 3:

[0059]

[0060] 2) Action

[0061] The action space of each virtual agent is [0, 1], where 0 means that the corresponding candidate is not used as a relay, and 1 means that the UE is used as a relay terminal.

[0062] 3) Status

[0063] The state consists of the Euclidian distances (EDs) between the agent terminals and the relay candidate UEs. If we have the kth agent a k The state of s k If expressed as a k All virtual agents including s have the same state for DQN training. k Use a k ED between the nth relay terminal and ED k If represented by [n], s k is expressed as follows:

[0064] Mathematical formula 4:

[0065]

[0066] 4) Compensation

[0067] Each agent terminal k has its own independent reward R k and has a global reward R G is calculated based on the rewards of all agent terminals. R k PRR is calculated based on the PRR obtained after all agent terminals have taken action. relay PRR is indicated as target PRRtarget This is obtained within the given coverage. If PRR relay This PRR target If satisfied, a positive reward is given. Otherwise, a penalty is given. R k is set to a value between 0 and 10, and PRR relay When =1, it has a maximum value of 10. In this case, R k is expressed as follows:

[0068] Mathematical formula 5:

[0069]

[0070] However, using individual rewards has a drawback. All agent terminals learn in a non-stationary environment while other agents adjust their actions during the training phase. This drawback is especially evident when using a DQN architecture, where the training phase relies on past experiences stored in replay memory. In a non-stationary environment, the association between current state-action pairs and past state-action pairs can weaken, leading to unstable training.

[0071] Therefore, the same global reward R G By using R for all agents, the actions of other agent terminals can reinforce the overall reward. In this case, R G is calculated as the average of all individual rewards and is expressed as follows:

[0072] Mathematical formula 6:

[0073]

[0074] Next, we will describe the resource allocation and transmission method for relay terminals. Whether a terminal is a relay terminal is indicated through the Step 1 SCI or the Step 2 SCI, and if indicated as a relay terminal, the message information can be decoded and the corresponding information can be utilized. At this time, the bit information of the Step 1 or 2 SCI can be utilized to indicate whether a terminal is a relay terminal. This part is added in the standard. After a relay terminal is selected, the selected relay terminal must be notified that it has been selected as a relay target to relay the agent's packet, and new resources for the relay must be allocated. The BSM Part 2 specified in SAE J 2735 can be utilized in the relay terminal resource allocation step. The BSM consists of BSM Part 1 and BSM Part 2. BSM Part 1 consists of essential information such as the vehicle ID, speed, angle, direction, position, and vehicle size. BSM Part 2 contains optional information that may or may not be present depending on the situation, such as the vehicle type (e.g., car, truck) and safety-related information (e.g., safety equipment status, airbag indicator light). Additionally, BSM Part 2 contains experimental fields whose content is not yet clearly defined. We propose using these experimental fields to indicate to relay terminals that they are relay terminals.

[0075] Additionally, agent terminals (transmitting terminals) must reserve resources for use by relay terminals in advance and broadcast instructions via SCI to prevent other terminals from using these reserved resources. Otherwise, conflicts may occur and performance may deteriorate due to the probability that other transmitting terminals will select the resources used by the relay terminal. The following three options are available for agent terminals to reserve resources for use by relay terminals in advance and broadcast these reserved resources via SCI.

[0076] (1) This is a method of always decoding up to the payload (BSM part2) in all surrounding terminals using application data (e.g., CAM message).

[0077] (2) This is a method that instructs decoding up to BSM part 2 by utilizing the free field value of SCI. This method cannot instruct whether to decode up to BSM part 2 only on specific terminals, but can perform payload decoding only for application data that requires relay.

[0078] (3) If additional unicast settings are available, this method utilizes unicast to instruct designated relay terminals to perform relaying. This method is superior in that it decodes up to BSM part 2 only on designated terminals and then performs relaying, but requires setting up an additional unicast connection in addition to the broadcast.

[0079] Figure 4 shows a block for selecting a relay terminal (vehicle) and a block for allocating resources to the relay terminal. After selecting a relay terminal, the agent terminal adds the ID of the selected vehicle and the TB index for the relay entity to BSM Part 2 and broadcasts BSM Part 2 to surrounding vehicles. Neighboring vehicles receiving BSM 2 of the agent terminal will ignore the information in BSM Part 2 if they are not the selected relay terminal. However, if the neighboring vehicle is the selected relay terminal, it relays the information in BSM Part 1 using the resources provided by the agent. Essentially, when allocating resources, the agent terminal must allocate resources not only for itself but also for the relay terminal. To this end, the agent terminal must know the ID of the surrounding vehicle and assume that it has received this information by receiving a BSM message previously transmitted by the surrounding vehicle. The timing at which the agent terminal selects the relay terminal is as shown in Figure 5. Referring to Figure 5, the agent terminal can receive the BSM broadcast from the neighboring terminal and select the relay terminal using the received BSM. Agent terminals can broadcast relay indicators to neighboring terminals via BSM 2.

[0080] Agent terminals can allocate resources to relay terminals based on the existing NR-mode 2. In NR-mode 2, UEs autonomously allocate resources through sensing and selection without the assistance of a base station. Simply put, each UE observes a resource pool during a sensing window. Agent terminals can allocate resources to both agent terminals and relay terminals by utilizing the sensing window (460). Agent terminals can preempt resources for the allocated resources using a 1st-Sidelink Channel Indicator (SCI) (470). Each terminal identifies resources preempted by other terminals using the 1st-SCI received from other terminals during the sensing window. Additionally, each terminal can measure the Reference Signal Received Power (RSRP) for each resource. Information related to the Reference Signal Received Power allows the UE to select an available transport block (TB). An agent terminal can broadcast a relay terminal indicator and an index of a specific resource (transmission block) allocated to the relay terminal (480). An agent terminal can broadcast a relay terminal indicator and an index of a specific resource (transmission block) allocated to the relay terminal using a two-step SCI.

[0081] Referring to FIGS. 6 and 7, these are diagrams for explaining SCI (Sidelink Channel Indicator). NR-V2X can be divided into 1-stage SCI and 2-stage SCI. 1-stage SCI is located in the PSCCH within the packet and includes information (QPSK, Polar coding) sensed by receiving vehicles. Referring to FIG. 6, an example showing a resource pool and transmission block structure is shown. 1-stage SCI contents may include the size of the frequency resource used (the subchannel used by the current packet), the time resource used (the time slot used by the current packet), the resource reservation period, the priority of the information contained in the PSSCH of the packet, the Beta-offset indicator, the format of the 2nd-SCI, the MCS information of the PSSCH, the DMRS pattern of the PSSCH, the number of DMRS, and the PSFCH indication. 2-stage SCI is located in the PSSCH above the PSCCH within the packet and includes information necessary to accurately decode the information contained in the payload. Referring to Figure 7, an example of a resource pool and transmission block structure is shown. The second-stage SCI content includes an HARQ process number, a new data indicator, a redundancy version, a source ID, a destination ID, an HARQ feedback enabled / disabled indicator, a cast type indicator, and a CSI request.

[0082] During the sensing window, the agent terminal excludes transport blocks already allocated by other terminals or transport blocks with RSRP values ​​exceeding a threshold. Then, if the remaining transport blocks within the sensing window account for more than 20% of the total resources, the transport block is designated as an available transport block. If the remaining transport blocks account for less than 20% of the total resources, the RSRP threshold is increased by 3 dB and an available transport block is selected again. This process can be repeated until at least 20% of the transport blocks are selected. After selection, the existing NR mode 2 allows the vehicle to randomly select transport blocks for its own use. Therefore, the agent terminal selects resources not only for itself but also for the relay entity. This allows the relay terminal to pre-allocate the resources it needs and mitigates possible resource conflicts because other terminals are aware that resources have already been reserved. In the embodiment, the resource allocation scheme for the relay terminal is referred to as resource reservation for the relay terminal.

[0083]

[0084] The devices described above may be implemented as hardware components, software components, and / or a combination of hardware components and software components. For example, the devices and components described in the embodiments may be implemented using one or more general-purpose computers or special-purpose computers, such as, for example, a processor, a controller, an arithmetic logic unit (ALU), a digital signal processor, a microcomputer, a field programmable gate array (FPGA), a programmable logic unit (PLU), a microprocessor, or any other device capable of executing instructions and responding to them. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to the execution of the software. For ease of understanding, the processing device is sometimes described as being used alone; however, one of ordinary skill in the art will recognize that the processing device may include multiple processing elements and / or multiple types of processing elements. For example, a processing unit may include multiple processors, or a processor and a controller. Other processing configurations, such as parallel processors, are also possible.

[0085] Software may include a computer program, code, instructions, or a combination of one or more of these, and may configure a processing device to perform a desired operation or, independently or collectively, command the processing device. The software and / or data may be embodied in any type of machine, component, physical device, virtual equipment, computer storage medium, or device for interpretation by the processing device or for providing instructions or data to the processing device. The software may be distributed over networked computer systems and stored or executed in a distributed manner. The software and data may be stored on one or more computer-readable recording media.

[0086] The method according to the embodiment may be implemented in the form of program commands that can be executed through various computer means and recorded on a computer-readable medium. The computer-readable medium may include program commands, data files, data structures, etc., alone or in combination. The program commands recorded on the medium may be those specially designed and configured for the embodiment or may be those known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, magneto-optical media such as floptical disks, and hardware devices specially configured to store and execute program commands such as ROMs, RAMs, and flash memories. Examples of program commands include not only machine language codes generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0087] Although the embodiments described above have been described by way of limited examples and drawings, those skilled in the art will appreciate that various modifications and variations can be made based on the above teachings. For example, appropriate results can still be achieved even if the described techniques are performed in a different order than described, and / or components of the described systems, structures, devices, circuits, etc. are combined or combined in a different manner than described, or are replaced or substituted with other components or equivalents.

[0088] Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the claims described below.

Claims

1. In a method for reserving resources in vehicle communication, A step of selecting multiple relay terminals based on whether to perform relaying; A step of reserving resources to be used by the agent terminal and the plurality of selected relay terminals to relay using resources provided from the agent terminal in the plurality of selected relay terminals; and A step of instructing the selected plurality of relay terminals to use the reserved resources. A method of reserving resources including:

2. In paragraph 1, The above reservation steps are: A step of broadcasting to surrounding vehicles using message information including vehicle identification information related to the plurality of selected relay terminals and a transmission block index for the relay terminal. Including, A resource reservation method characterized in that, when the surrounding vehicle receives message information, if the surrounding vehicle is not a relay terminal, the message information is ignored, and if the surrounding vehicle is a relay terminal, the surrounding vehicle relays other message information using the resources provided from the agent terminal.

3. In paragraph 1, The above reservation steps are: A step of reserving resources to be used by the agent terminal and the selected plurality of relay terminals during a sensing window set in the agent terminal, and preempting the reserved resources using a 1st-Sidelink Channel Indicator (SCI) A method of reserving resources including:

4. In paragraph 3, The above reservation steps are: A step of identifying resources preempted by each terminal using the 1st-Sidelink Channel Indicator (SCI) sensed from each terminal of surrounding vehicles, and selecting an available transmission block by measuring the reference signal reception strength in the resources preempted from each terminal. A method of reserving resources including:

5. In paragraph 4, The above reservation steps are: A step of excluding transmission blocks already allocated to each terminal or transmission blocks with a reference signal reception strength exceeding a threshold. A method of reserving resources including:

6. In paragraph 5, The above reservation steps are: A step of designating the remaining transport blocks as available transport blocks when the remaining transport blocks within the sensing window are greater than or equal to the preset value of the total resources. A method of reserving resources including:

7. In paragraph 5, The above reservation steps are: A step of increasing the reference signal reception strength threshold by a preset value when the remaining transmission blocks within the sensing window are less than the preset value of the entire resource, and then repeating the process of selecting a transmission block that is available again until the transmission block reaches the preset value. A method of reserving resources including:

8. In paragraph 1, The above resource reservation method is, A resource reservation method characterized by indicating whether a relay terminal is indicated through a 1-step SCI or a 2-step SCI, and decoding message information when the relay terminal is indicated.

9. In paragraph 1, The above instructions are as follows: A step of broadcasting information about the reserved resources to the selected plurality of relay terminals through a 1st or 2nd-Sidelink Channel Indicator (SCI). A method of reserving resources including:

10. In paragraph 9, The above instructions are as follows: A step of instructing each terminal to decode message information using application data. A method of reserving resources including:

11. In paragraph 9, The above instructions are as follows: A step for instructing to decode the message information using the spare field value of the above step 1 or step 2 SCI. A method of reserving resources including:

12. In paragraph 9, The above instructions are as follows: A step of instructing the multiple relay terminals selected above to perform relaying through unicast settings. A method of reserving resources including:

13. In paragraph 1, The above reservation steps are: A step of selecting resources for the selected plurality of relay terminals by additionally considering sensing information of surrounding terminals based on the above agent terminal. A method of reserving resources including:

14. In paragraph 1, The above instructions are as follows: When broadcasting to the plurality of selected relay terminals, a step of commonly allocating resources to be used by the plurality of selected relay terminals to the selected relay terminals. A method of reserving resources including:

15. In the resource reservation system, A terminal selection unit for selecting multiple relay terminals according to whether to perform relaying; and A resource reservation unit that reserves resources to be used by the agent terminal and the plurality of selected relay terminals to relay using resources provided from the agent terminals in the plurality of selected relay terminals; and A directive section that instructs the selected plurality of relay terminals to use the reserved resources above. A resource reservation system including:

Images