Service maintenance method, relay device, and medium in a side link relay system

Abstract

A method for maintaining services in a side link relay system, a relay device, and a medium. The method includes: when configured to request to forward multicast services, receiving feedback from a user equipment on a transmitted data packet; and determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet. By adopting the above solution, the utilization efficiency of radio resources during the forwarding of MBMS services in a relay scenario can be improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and particularly to a service maintenance method, a relay device, and a medium in a sidelink relay system. Background Art

[0002] The device-to-device direct communication technology or the sidelink (SL) communication technology is different from the traditional wireless cellular network communication. In the traditional cellular network, a user equipment communicates with a base station equipment. At this time, the link between the user equipment and the base station equipment is called an uplink (UL) or a downlink (DL), and the interface is called a Uu interface. In the device-to-device direct communication, the user equipment communicates directly with the user equipment. The link between the user equipment and the user equipment is called a sidelink (SL), and the interface is called a PC5 interface.

[0003] The introduction of the sidelink was initially to enable direct communication between users at relatively close distances. The data does not need to be forwarded by the base station, reducing the transmission delay. Based on the sidelink, the sidelink relay was designed. The sidelink relay means that the link between the relay and the user equipment (UE) uses the sidelink technology, while the traditional relay and the UE use the uplink and downlink technologies.

[0004] Refer to Figure 1 , a schematic diagram of an existing traditional relay structure is given. The base station and the relay device communicate through the uplink and downlink, and the relay device and the user equipment communicate through the uplink and downlink. Refer to Figure 2 , a schematic diagram of an existing sidelink relay structure is given. Different from Figure 1 , Figure 2 , between the relay device and the user equipment communicates through the sidelink (SL).

[0005] The relay can be used to forward unicast data and multicast data. The target receiving users of the multicast data are the users interested in a certain multicast service, and the multicast service can be a television service. In 3GPP Rel-13, if the relay device determines that there is no user equipment interested in a certain multicast service, the relay device can stop forwarding the multicast service.

[0006] In 3GPP Rel-13, the forwarding of the Multimedia Broadcast / Multicast Service (MBMS) in the relay scenario is achieved by the user equipment periodically re-requesting the MBMS service, resulting in a waste of resources. Summary of the Invention

[0007] The embodiment of the present invention solves the technical problem of waste of radio resources in the forwarding of MBMS services in the relay scenario.

[0008] To solve the above technical problem, the embodiment of the present invention provides a method for maintaining services in a sidelink relay system, including: when being configured to request to forward multicast services, receiving feedback from a user equipment on a transmitted data packet; determining to stop forwarding the currently ongoing MBMS service or continue to forward the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet.

[0009] Optionally, the receiving feedback from the user equipment on the transmitted data packet includes: receiving the feedback from the user equipment on the transmitted data packet on a physical sidelink feedback signal resource.

[0010] Optionally, the determining to stop forwarding the currently ongoing MBMS service or continue to forward the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet includes: when it is detected that no feedback from any user equipment on the transmitted data packet is received continuously for N times, determining to stop forwarding the currently ongoing MBMS service; N≥1, and the feedback on the transmitted data packet includes HARQ ACK and HARQ NACK.

[0011] Optionally, the determining to stop forwarding the currently ongoing MBMS service or continue to forward the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet includes: when it is detected that HARQ ACK feedback from the user equipment is not successfully received continuously for N times, determining to stop forwarding the currently ongoing MBMS service; N≥1.

[0012] Optionally, the determining to stop forwarding the currently ongoing MBMS service when it is detected that HARQ ACK feedback from the user equipment is not successfully received continuously for N times includes: when it is detected that the feedback on the transmitted data packet received from the user equipment is HARQ NACK continuously for N times, determining to stop forwarding the currently ongoing MBMS service; N≥1.

[0013] Optionally, the determining to stop forwarding the currently ongoing MBMS service when it is detected that HARQ ACK feedback from the user equipment is not successfully received continuously for N times includes: when it is detected that the feedback on the transmitted data packet received continuously for N times includes M times of HARQ NACK and N-M times of unsuccessful feedback, determining to stop forwarding the currently ongoing MBMS service; 0≤M≤N, N≥1.

[0014] Optionally, determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packet includes: when detecting the feedback of any user equipment on the transmitted data packet, determining to continue forwarding the currently ongoing MBMS service and restarting the timer; the feedback on the transmitted data packet includes ACK and NACK.

[0015] Optionally, determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packet includes: when detecting that the feedback of any user equipment on the transmitted data packet is ACK, determining to continue forwarding the currently ongoing MBMS service and restarting the timer.

[0016] To solve the above technical problems, an embodiment of the present invention further provides a relay device, including: a receiving unit, configured to receive the feedback of the user equipment on the transmitted data packet when being configured to request to forward the multicast service; a determining unit, configured to determine to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packet.

[0017] An embodiment of the present invention further provides a computer-readable storage medium, which is a non-volatile storage medium or a non-transient storage medium, on which a computer program is stored, and when the computer program is run by a processor, it executes the steps of the service maintenance method in any one of the above side link relay systems.

[0018] An embodiment of the present invention further provides another relay device, including a memory and a processor, where a computer program that can run on the processor is stored on the memory, and when the processor runs the computer program, it executes the steps of the service maintenance method in any one of the above side link relay systems.

[0019] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0020] When being configured to request to forward the multicast service, receive the feedback of the user equipment on the transmitted data packet, and determine to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service. When determining whether to continue forwarding the currently ongoing MBMS service through the feedback of the user equipment on the transmitted data packet, it can effectively avoid the user equipment from frequently re-requesting the MBMS service, and enable the relay device to stop forwarding the MBMS service in a timely manner.

[0021] Furthermore, after detecting the feedback of any user equipment on the transmitted data packet, restart the timer to avoid terminating the currently ongoing MBMS service due to the timeout of the timer. Description of the Drawings

[0022] Figure 1 is a schematic diagram of a conventional relay structure in the prior art;

[0023] Figure 2 is a schematic diagram of an edge link relay structure in the prior art;

[0024] Figure 3 is a flowchart of a service maintenance method in an edge link relay system according to an embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of a user equipment according to an embodiment of the present invention. Detailed Embodiments

[0026] In 3GPP Rel-13, when a user equipment is interested in a certain multicast service, the following process can be adopted to request a relay device to forward the multicast service: First, the user equipment sends a request message: TMGI_MONITORING_REQUEST, which carries at least the identification information of the interested MBMS service. The relay device correspondingly feeds back TMGI_MONITORING_RESPNESE information, which carries a group ID (group ID). The user equipment receives the interested MBMS service by listening to the group ID.

[0027] When the relay device sends the TMGI_MONITORING_RESPNESE information, it starts or restarts the T4105 timer. When the T4105 timer expires, the relay device stops forwarding the MBMS service.

[0028] When the user equipment receives the TMGI_MONITORING_RESPNESE information, it starts or restarts the T4104 timer. When the T4104 timer expires, if the user equipment is still interested in the MBMS service, the user equipment re-sends the TMGI_MONITORING_RESPNESE information, that is, re-requests the relay device to forward the MBMS service.

[0029] That is to say, in 3GPP Rel-13, the relay device forwards the MBMS service by the user equipment periodically re-requesting the MBMS service. If the timing durations configured for the T4104 and T4105 timers are short, it will cause the user equipment to frequently re-request the MBMS service; if the timing durations configured for the T4104 and T4105 timers are long, it will cause the relay device to be unable to stop forwarding the MBMS service in time. Both of the above scenarios will result in waste of wireless resources.

[0030] In an embodiment of the present invention, when determining whether to continue forwarding the currently ongoing MBMS service based on the feedback of the data packets transmitted by the user equipment, it is possible to effectively avoid the user equipment from frequently re-requesting the MBMS service, and enable the relay device to stop forwarding the MBMS service in a timely manner.

[0031] To make the above objects, features, and beneficial effects of the present invention more obvious and understandable, the following describes the specific embodiments of the present invention in detail with reference to the accompanying drawings.

[0032] An embodiment of the present invention provides a service maintenance method in a sidelink relay system. Referring to Figure 3 , the following is a detailed description through specific steps.

[0033] Step S301: When configured to request to forward the multicast service, receive the feedback of the user equipment on the transmitted data packets.

[0034] In a specific implementation, the network side can configure the relay device and the user equipment, where: the relay device is configured to request to forward the multicast service, and each user equipment is configured to feedback HARQ ACK or HARQ NACK according to the decoding request of each transmitted data packet.

[0035] In an embodiment of the present invention, the user equipment can feedback the feedback on the transmitted data packets on the Physical Sidelink Feedback Channel (PSFCH) resource, and the feedback of the user equipment can be HARQ ACK or HARQ NACK. The relay device can receive the feedback of the user equipment on the PSFCH resource.

[0036] Step S302: Determine to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packets.

[0037] In a specific implementation, when it is detected that no feedback from any user equipment on the transmitted data packets has been received continuously for N times, it can be determined that the user equipment within the coverage range of the relay device is not interested in the MBMS service forwarded by the relay device. Therefore, it can be determined to stop forwarding the currently ongoing MBMS service. N can be 1, or 2, or a larger integer value.

[0038] In an embodiment of the present invention, the relay device can record the number of times that HARQ ACK / HARQ NACK has not been successfully received. When HARQ ACK or HARQ NACK feedback from any user equipment has not been successfully received continuously for N times, the relay device can terminate forwarding the currently ongoing MBMS service without waiting for the T4105 timer to expire.

[0039] In other words, in the embodiments of the present invention, when the relay device fails to successfully receive HARQ ACK or HARQ NACK fed back by any user equipment for N consecutive times, the relay device can terminate the forwarding of the current MBMS service in advance, improving the utilization efficiency of wireless resources.

[0040] In a specific implementation, the relay device can record the number of times of failing to successfully receive HARQ ACK. When the relay device fails to successfully receive HARQ ACK for N consecutive times, the relay device can terminate the forwarding of the current MBMS service without waiting for the T4105 timer to time out.

[0041] In other words, in the embodiments of the present invention, when the relay device fails to successfully receive HARQ ACK for N consecutive times, the relay device can terminate the forwarding of the current MBMS service in advance, improving the utilization efficiency of wireless resources.

[0042] In a specific implementation, the scenarios where the relay device fails to successfully receive HARQ ACK for N consecutive times include the following: The relay device detects that a user equipment sends feedback, but for N consecutive times, the feedback of the user equipment on the transmitted data packet is HARQ NACK. At this time, the relay device can determine that the user equipment is not interested in the MBMS service forwarded by the relay device, and the relay device can determine to stop forwarding the current MBMS service. N can be 1, or 2, or a larger integer value.

[0043] For example, there are 4 user equipments within the coverage of the relay device, and N = 2. The relay device records that the feedback of the data packet transmitted for the first time is that all 4 user equipments feed back HARQ NACK, and records that the feedback of the data packet transmitted for the second time is that all 4 user equipments feed back HARQ NACK. At this time, the relay device can determine to stop forwarding the current MBMS service.

[0044] In the embodiments of the present invention, the scenarios where the relay device fails to successfully receive HARQ ACK for N consecutive times also include the following: When transmitting data packets for N consecutive times, there are N - M times of failing to successfully receive HARQ ACK / HARQ NACK, and there are M times of receiving HARQ NACK. At this time, the relay device can determine that the user equipment is not interested in the forwarded MBMS service, and the relay device can determine to stop forwarding the current MBMS service, where 0 ≤ M ≤ N.

[0045] For example, there are two user equipments within the coverage area of the relay device. When transmitting a data packet for the first time, the relay device does not receive a HARQ ACK / HARQ NACK feedback from any of the user equipments; when transmitting the data packet for the second time, the relay device receives a HARQ NACK feedback from user equipment 1 and does not receive a HARQ ACK / HARQ NACK feedback from user equipment 2, then it is determined that the HARQ ACK feedback from the user equipment has not been successfully received for 2 consecutive times; when transmitting the data packet for the third time, the relay device receives a HARQ NACK feedback from user equipment 1 and a HARQ NACK feedback from user equipment 2, then it is determined that the HARQ ACK feedback from the user equipment has not been successfully received for 3 consecutive times.

[0046] That is to say, the relay device fails to successfully receive the HARQ ACK for N consecutive times, and the N times refer to the number of times of transmitting data packets. After each transmission of a data packet, the relay device can detect whether it has received the feedback from the user equipment, and whether the received feedback from the user equipment is a HARQ ACK or a HARQ NACK. If the relay device detects that no user equipment feeds back a HARQ ACK, it can be determined that the HARQ ACK for this transmission of the data packet has not been successfully received. There are two cases corresponding to the user equipment not feeding back a HARQ ACK: the user equipment feeds back a HARQ NACK, or the user equipment does not feed back on the data packet transmitted this time (that is, the user equipment does not feed back a HARQ NACK and a HARQ ACK).

[0047] In a specific implementation, when the relay device detects the feedback of any user equipment on the transmitted data packet, regardless of whether the feedback of the user equipment on the transmitted data packet is an ACK or a NACK, it can be determined that the user equipment is interested in the current ongoing MBMS service. Therefore, the relay device can forward the current ongoing MBMS service and restart the T4105 timer.

[0048] In a specific implementation, when the relay device detects the feedback of any user equipment on the transmitted data packet, if the feedback of the user equipment on the transmitted data packet is an ACK, it can be determined that the user equipment is interested in the current ongoing MBMS service. Therefore, the relay device can forward the current ongoing MBMS service and restart the T4105 timer.

[0049] In practical applications, it can be known that the T4105 timer is a timer set in the relay device as specified in the 3GPP protocol. When the relay sends the TMGI_MONITORING_RESPNESE message, it will start or restart the T4105 timer. When the T4105 timer times out, the relay device stops forwarding this MBMS service.

[0050] It can be seen that in the embodiments of the present invention, when it is determined that the user equipment is interested in the currently ongoing MBMS service, the relay device restarts the T4105 timer, thereby avoiding the situation where the currently ongoing MBMS service is stopped due to the timeout of the T4105 timer.

[0051] In other words, if the relay device detects a user equipment interested in the currently ongoing MBMS service during the process of forwarding the MBMS service, the T4105 timer of the relay device will not time out until it is detected that all user equipments are not interested in the currently ongoing MBMS service.

[0052] As can be seen from the above, in the embodiments of the present invention, when determining whether to continue forwarding the currently ongoing MBMS service based on the feedback of the user equipment on the transmitted data packet, it is possible to effectively avoid the user equipment frequently re-requesting the MBMS service and enable the relay device to stop forwarding the MBMS service in a timely manner.

[0053] Referring to Figure 4 , the embodiments of the present invention further provide a relay device 40, including: a receiving unit 401 and a determining unit 402, where:

[0054] The receiving unit 401 is configured to receive the feedback of the user equipment on the transmitted data packet when being configured to request forwarding of the multicast service;

[0055] The determining unit 402 is configured to determine whether to stop forwarding the currently ongoing MBMS service or continue to forward the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packet.

[0056] In specific implementation, the specific working processes of the above receiving unit 401 and determining unit 402 can refer to the above steps S101 to S102, which will not be elaborated here.

[0057] The embodiments of the present invention further provide a computer-readable storage medium, which is a non-volatile storage medium or a non-transitory storage medium, on which a computer program is stored, and when the computer program is run by a processor, it executes the steps of the service maintenance method in the side-link relay system provided in any of the above embodiments.

[0058] The embodiments of the present invention further provide another relay device, including a memory and a processor, where a computer program that can run on the processor is stored on the memory, and when the processor runs the computer program, it executes the steps of the service maintenance method in the side-link relay system provided in any of the above embodiments.

[0059] Those of ordinary skill in the art can understand that all or part of the steps in the various methods of the above embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium, which can include: ROM, RAM, magnetic disk, optical disk, etc.

[0060] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. A method for maintaining services in a sidelink relay system, characterized in that, applied to a relay device, including: When configured to request to forward multicast services, receiving feedback from a user equipment on the transmitted data packet; Determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet, including: when it is detected that no feedback from any user equipment on the transmitted data packet is received for N consecutive times, or when it is detected that HARQ ACK feedback from the user equipment is not successfully received for N consecutive times, determining to stop forwarding the currently ongoing MBMS service; the feedback on the transmitted data packet includes HARQ ACK and HARQ NACK; N≥1.

2. The method for maintaining services in a sidelink relay system according to claim 1, characterized in that, the receiving the feedback from the user equipment on the transmitted data packet includes: Receiving the feedback from the user equipment on the transmitted data packet on a physical sidelink feedback signal resource.

3. The method for maintaining services in a sidelink relay system according to claim 1, characterized in that, the determining to stop forwarding the currently ongoing MBMS service when it is detected that HARQ ACK feedback from the user equipment is not successfully received for N consecutive times includes: When it is detected that the feedback from the user equipment on the transmitted data packet received for N consecutive times is HARQ NACK, determining to stop forwarding the currently ongoing MBMS service; N≥1.

4. The method for maintaining services in a sidelink relay system according to claim 1, characterized in that, the determining to stop forwarding the currently ongoing MBMS service when it is detected that HARQ ACK feedback from the user equipment is not successfully received for N consecutive times includes: When it is detected that the feedback on the transmitted data packet received for N consecutive times includes M times of HARQ NACK and N - M times of unsuccessful feedback, determining to stop forwarding the currently ongoing MBMS service; 0≤M≤N, N≥1.

5. The method for maintaining services in a sidelink relay system according to claim 1 or 2, characterized in that, the determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet includes: When it is detected that there is feedback from any user equipment on the transmitted data packet, determining to continue forwarding the currently ongoing MBMS service and restarting the timer.

6. The method for maintaining services in a sidelink relay system according to claim 1 or 2, characterized in that, the determining to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback from the user equipment on the transmitted data packet includes: When it is detected that the feedback from any user equipment on the transmitted data packet is ACK, determining to continue forwarding the currently ongoing MBMS service and restarting the timer.

7. A relay device, characterized in that, including: A receiving unit, configured to receive feedback from a user equipment on the transmitted data packet when configured to request to forward multicast services; A determination unit, configured to determine whether to stop forwarding the currently ongoing MBMS service or continue forwarding the currently ongoing MBMS service according to the feedback of the user equipment on the transmitted data packet, includes: when it is detected that no feedback from any user equipment on the transmitted data packet has been received for N consecutive times, or it is detected that the HARQ ACK feedback from the user equipment has not been successfully received for N consecutive times, determine to stop forwarding the currently ongoing MBMS service; the feedback on the transmitted data packet includes HARQ ACK and HARQ NACK; N≥1.

8. A computer-readable storage medium, which is a non-volatile storage medium or a non-transitory storage medium, and has a computer program stored thereon, characterized in that when the computer program is run by a processor, it executes the steps of the service maintenance method in the sidelink relay system according to any one of claims 1 to 6.

9. A relay device, comprising a memory and a processor, and having a computer program stored on the memory that can be run on the processor, characterized in that when the processor runs the computer program, it executes the steps of the service maintenance method in the sidelink relay system according to any one of claims 1 to 6.

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