Methods, devices, and systems for device to device (D2D) data transmission and retransmission
Embodiments of this application disclose a data transmission method, including: sending, by a base station, first scheduling information to first UE, where the first scheduling information is used to instruct the first UE to send data to second UE based on the first scheduling information; receiving, by the base station, first feedback information sent by the first UE; and sending, by the base station, second scheduling information to the first UE if the first feedback information indicates that the second UE fails to receive the data. The embodiments of this application further provide a base station, UE, and a data transmission system.
1. A method, comprising:
sending, by a network apparatus, first scheduling information indicating a plurality of sidelink (SL) time resources to a first terminal apparatus, the plurality of SL time resources are for the first terminal apparatus to send data to a second terminal apparatus;
receiving, by the network apparatus, first feedback information after a last SL time resource of the plurality of SL time resources from the first terminal apparatus, wherein the first feedback information indicates whether the second terminal apparatus successfully receives the data, the first feedback information is determined based on second feedback information, and the second feedback information is from the second terminal apparatus to the first terminal apparatus; and
sending, by the network apparatus, based on the first feedback information indicating that the second terminal apparatus fails to receive the data, second scheduling information indicating a second plurality of SL time resources to the first terminal apparatus, the second plurality of SL time resources including a second SL time resource, wherein the second scheduling information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus using the second SL time resource.
2. The method according to claim 1 , wherein the first scheduling information includes indication information indicating that the data can be retransmitted.
3. The method according to claim 2 ,
wherein the second feedback information is an acknowledgement (ACK), and the first feedback information is the ACK, or
wherein the second feedback information is a negative acknowledgement (NACK), and the first feedback information is the NACK, or
wherein the first terminal apparatus fails to receive the second feedback information, and the first feedback information is a NACK.
4. The method according to claim 1 , further comprising:
sending, by the network apparatus, downlink feedback information to the first terminal apparatus, wherein the downlink feedback information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus based on the first scheduling information.
5. A method, comprising:
receiving, by a first terminal apparatus, first scheduling information indicating a plurality of sidelink (SL) time resources from a network apparatus, the plurality of SL time resources are for the first terminal apparatus to send data to a second terminal apparatus;
sending, by the first terminal apparatus, first feedback information after a last SL time resource of the plurality of SL time resources to the network apparatus, wherein the first feedback information indicates whether the second terminal apparatus successfully receives the data, the first feedback information is determined based on second feedback information, and the second feedback information is from the second terminal apparatus to the first terminal apparatus; and
receiving, by the first terminal apparatus, based on the first feedback information indicating that the second terminal apparatus fails to receive the data, second scheduling information indicating a second plurality of SL time resources from the network apparatus, the second plurality of SL time resources including a second SL time resource, wherein the second scheduling information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus using the second SL time resource.
6. The method according to claim 5 , wherein the first scheduling information includes indication information indicating that the data can be retransmitted.
7. The method according to claim 6 ,
wherein the second feedback information is an acknowledgement (ACK), the first feedback information is the ACK, or
wherein the second feedback information is a negative acknowledgement (NACK), the first feedback information is the NACK, or
wherein the first terminal apparatus fails to receive the second feedback information, the first feedback information is a NACK.
8. The method according to claim 5 , further comprising:
receiving, by the first terminal apparatus, downlink feedback information from the network apparatus, wherein the downlink feedback information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus based on the first scheduling information.
9. A network apparatus, comprising:
one or more processors; and
a non-transitory memory, wherein the non-transitory memory stores instructions, and when executing the instructions stored in the non-transitory memory, the network apparatus executes operations comprising:
sending, first scheduling information indicating a plurality of sidelink (SL) time resources to a first terminal apparatus, the plurality of SL time resources are for the first terminal apparatus to send data to a second terminal apparatus;
receiving, first feedback information after a last SL time resource of the plurality of SL time resources from the first terminal apparatus, wherein the first feedback information indicates whether the second terminal apparatus successfully receives the data, the first feedback information is determined based on second feedback information, and the second feedback information is from the second terminal apparatus to the first terminal apparatus; and
sending, based on the first feedback information indicating that the second terminal apparatus fails to receive the data, second scheduling information indicating a second plurality of SL time resources to the first terminal apparatus, the second plurality of SL time resources including a second SL time resource, wherein the second scheduling information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus using the second SL time resource.
10. The network apparatus according to claim 9 , wherein the first scheduling information includes indication information indicating that the data can be retransmitted.
11. The network apparatus according to claim 10 ,
wherein the second feedback information is an acknowledgement (ACK), and the first feedback information is the ACK, or
wherein the second feedback information is a negative acknowledgement (NACK), and the first feedback information is the NACK, or
wherein the first terminal apparatus fails to receive the second feedback information, and the first feedback information is a NACK.
12. The network apparatus according to claim 9 , the operations further comprising:
sending downlink feedback information to the first terminal apparatus, wherein the downlink feedback information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus based on the first scheduling information.
13. A first terminal apparatus, comprising:
one or more processors; and
a non-transitory memory, wherein the non-transitory memory stores instructions, and when executing the instructions stored in the non-transitory memory, the first terminal apparatus executes operations comprising:
receiving, first scheduling information indicating a plurality of sidelink (SL) time resources from a network apparatus, the plurality of SL time resources are for the first terminal apparatus to send data to a second terminal apparatus;
sending, first feedback information after a last SL time resource of the plurality of SL time resources to the network apparatus, wherein the first feedback information indicates whether the second terminal apparatus successfully receives the data, the first feedback information is determined based on second feedback information, and the second feedback information is from the second terminal apparatus to the first terminal apparatus; and
receiving, based on the first feedback information indicating that the second terminal apparatus fails to receive the data, second scheduling information indicating a second plurality of SL time resources from the network apparatus, the second plurality of SL time resources including a second SL time resource, wherein the second scheduling information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus using the second SL time resource.
14. The first terminal apparatus according to claim 13 , wherein the first scheduling information includes indication information indicating that the data can be retransmitted.
15. The first terminal apparatus according to claim 14 ,
wherein the second feedback information is an acknowledgement (ACK), and the first feedback information is the ACK, or
wherein the second feedback information is a negative acknowledgement (NACK), and the first feedback information is the NACK, or
wherein the first terminal apparatus fails to receive the second feedback information, and the first feedback information is a NACK.
16. The first terminal apparatus according to claim 13 , the operations further comprising:
receiving downlink feedback information from the network apparatus, wherein the downlink feedback information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus based on the first scheduling information.
17. A non-transitory computer readable medium storing instructions that, when executed by a first terminal apparatus, causes the first terminal apparatus to execute operations comprising:
receiving, first scheduling information indicating a plurality of sidelink (SL) time resources from a network apparatus, the plurality of SL time resources are for the first terminal apparatus to send data to a second terminal apparatus;
sending, first feedback information after a last SL time resource of the plurality of SL time resources to the network apparatus, wherein the first feedback information indicates whether the second terminal apparatus successfully receives the data, the first feedback information is determined based on second feedback information, and the second feedback information is from the second terminal apparatus to the first terminal apparatus; and
receiving, based on the first feedback information indicating that the second terminal apparatus fails to receive the data, second scheduling information indicating a second plurality of SL time resources from the network apparatus, the second plurality of SL time resources including a second SL time resource, wherein the second scheduling information instructs the first terminal apparatus to retransmit the data to the second terminal apparatus using the second SL time resource.