Method and apparatus in sidelink communication

1. An apparatus comprising a base station, the apparatus further comprising:

a transceiver that:

transmits, to a relay unit, first resource information indicating a first resource pool for sidelink (SL) communication, wherein the first resource pool includes SL transmission resources and SL reception resources;

receives, from the relay unit, at least two parameters selected from the group comprising: a channel state, a ratio, a buffer status of the relay unit, a buffer status report of one or more remote units, a first buffer state of uplink (UL) transmission of the relay unit, a second buffer state of SL transmission and reception of the relay unit, an expected payload size of UL transmission data and SL transmission and reception data of the relay unit, a traffic type, a traffic period, a traffic priority, a traffic payload size, or some combination thereof; and

receives, from the relay unit, an indication of a first resources pair selected by the relay unit from the first resources pool, wherein the first resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources; and

a processor that determines a modification to the first resource pool, the modification to the first resource pool is determined based on the received indication and the at least two parameters selected from the group comprising: the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof;

wherein the transceiver transmits second resource information indicating the modification to the first resource pool for SL transmission and reception to the relay unit.

2. A method of a base station, the method comprising:

transmit, to a relay unit, first resource information indicating a first resource pool for sidelink (SL) communication, wherein the first resource pool includes SL transmission resources and SL reception resources;

receiving, from the relay unit, at least two parameters selected from the group comprising: a channel state, a ratio, a buffer status of the relay unit, a buffer status report of one or more remote units, a first buffer state of uplink (UL) transmission of the relay unit, a second buffer state of sidelink transmission and reception of the relay unit, an expected payload size of UL transmission data and SL transmission and reception data of the relay unit, a traffic type, a traffic period, a traffic priority, a traffic payload size, or some combination thereof;

receiving, from the relay unit, an indication of a first resources pair selected by the relay unit from the first resources pool, wherein the first resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources;

determining a modification to the first resource pool, wherein the modification to the first resource pool is determined based on the received indication and the at least two parameters selected from the group comprising: the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof; and

transmitting second resource information indicating the modification to the first resource pool for SL transmission and reception from an apparatus to the relay unit.

3. The method according to claim 2 , wherein the first resources pool is a SL subframes pool including SL transmission subframes and SL reception subframes, and the resources information is information about SL subframes.

4. The method according to claim 2 , wherein the first resources pool is a semi-persistent scheduling (SPS) configurations pool including SL transmission SPS configurations and SL reception SPS configurations, and the resources information is information about SL SPS configurations.

5. The method according to claim 2 , wherein the resources information is the first resources pool which is transmitted to the relay unit by a higher layer signaling.

6. The method according to claim 2 , wherein the first resources pair is selected by the relay unit based on the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.

7. The method according to claim 2 , further comprising:

determining a second resources pool; and

transmitting the second resources pool to the relay unit by the higher layer signaling.

8. The method according to claim 7 , further comprising:

not scheduling a UL transmission for the relay unit on one of more of SL transmission resources, SL reception resources in a resource pair for SL communication, and the resource pair for SL communication.

9. The method according to claim 2 , further comprising:

determining a second resources pair for SL communication which is different with the first resources pair selected by the relay unit, the second resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources; and

transmitting the second resources pair to the relay unit by a downlink control signaling.

10. The method according to claim 2 , further comprising:

confirming the selection of the first resources pair for SL communication by the relay unit; and

transmitting an indication that the selection of the first resources pair for SL communication by the relay unit is confirmed.

11. The method according to claim 2 , further comprising:

pre-configuring a priority flag which indicates a priority between UL transmission and SL transmission and reception, wherein if the priority flag indicates that the priority of UL transmission is higher than that of SL transmission and reception for the relay unit, the relay unit waits for a confirmation from the apparatus in response to the selection of the first resources pair for SL communication by the relay unit, otherwise, the relay unit performs SL communication using the first resources pair; and

transmitting the priority flag to the relay unit by a higher layer signaling or a downlink control signaling.

12. The method according to claim 2 , wherein the resources information is a second resources pair selected by the apparatus and transmitted to the relay unit by a downlink control signaling, and the second resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources.

13. The method according to claim 12 , wherein the second resources pair is selected by the apparatus based on the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.

14. An apparatus comprising a relay unit, the apparatus further comprising:

a transceiver that:

receives, from a base station, first resource information indicating a first resource pool for sidelink (SL) communication, wherein the first resource pool includes SL transmission resources and SL reception resources;

transmits, to the base station, at least two parameters selected from the group comprising: a channel state, a ratio, a buffer status of the relay unit, a buffer status report of one or more remote units, a first buffer state of uplink (UL) transmission of the relay unit, a second buffer state of sidelink (SL) transmission and reception of the relay unit, an expected payload size of UL transmission data and SL transmission and reception data of the relay unit, a traffic type, a traffic period, a traffic priority, a traffic payload size, or some combination thereof;

transmits, to the base station, an indication of a first resources pair selected by the relay unit from the first resources pool, wherein the first resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources; and

receives second resources information indicating a modification to the first resource pool from the base station, wherein the modification to the first resource pool is determined based on the transmitted indication and the at least two parameters selected from the group comprising: the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.

15. A method of a relay unit, the method comprising:

receiving, from a base station, first resource information indicating a first resource pool for sidelink (SL) communication, wherein the first resource pool includes SL transmission resources and SL reception resources;

transmitting, to the base station, at least two parameters selected from the group comprising: a channel state, a ratio, a buffer status of the relay unit, a buffer status report of one or more remote units, a first buffer state of uplink (UL) transmission of the relay unit, a second buffer state of sidelink (SL) transmission and reception of the relay unit, an expected payload size of UL transmission data and SL transmission and reception data of the relay unit, a traffic type, a traffic period, a traffic priority, a traffic payload size, or some combination thereof;

transmitting, to the base station, an indication of a first resources pair selected by the relay unit from the first resources pool, wherein the first resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources; and

receiving second resources information indicating a modification to the first resource pool from the base station, wherein the modification to the first resource pool is determined based on the transmitted indication and the at least two parameters selected from the group comprising: the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.

16. The method according to claim 15 , wherein the first resources pool is a SL subframes pool including SL transmission subframes and SL reception subframes, and the resources information is information about SL subframes.

17. The method according to claim 15 , wherein the first resources pool is a semi-persistent scheduling (SPS) configurations pool including SL transmission SPS configurations and SL reception SPS configurations, and the resources information is information about SL SPS configurations.

18. The method according to claim 15 , wherein the resources information is the resources pool which is transmitted from the network equipment by a higher layer signaling.

19. The method according to claim 18 , further comprising:

selecting the first resources pair from the first resources pool.

20. The method according to claim 19 , wherein the first resources pair is selected by the apparatus based on the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.

21. The method according to claim 19 , further comprising receiving a second resources pool from the network equipment by the higher layer signaling.

22. The method according to claim 21 , further comprising, if there is a UL scheduling in the SL reception resources of the resource pair for SL communication, prioritizing SL reception over UL transmission in the SL reception resources of the resource pair for SL communication.

23. The method according to claim 19 , further comprising receiving a second resources pair for SL communication, which is different with the first resources pair selected by the apparatus, from the network equipment by a downlink control signaling, the second resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to SL transmission resources.

24. The method according to claim 19 , further comprising receiving an indication from the network equipment that the selection of the first resources pair for SL communication by the apparatus is confirmed.

25. The method according to claim 19 , further comprising receiving a priority flag from the network equipment by a higher layer signaling or a downlink control signaling, which indicates a priority between UL transmission and SL transmission and reception, wherein if the priority flag indicates that the priority of UL transmission is higher than that of SL transmission and reception for a relay unit, the relay unit waits for a confirmation from the network equipment in response to the selection of the first resources pair for SL communication by the apparatus, otherwise, the apparatus performs SL communication using the first resources pair.

26. The method according to claim 15 , wherein the resources information is a second resources pair selected by the apparatus and transmitted from the network equipment by a downlink control signaling, and the second resources pair includes SL transmission resources and SL reception resources, and the SL reception resources are corresponding to the SL transmission resources.

27. The method according to claim 26 , wherein the second resources pair is selected by the network equipment based on the channel state, the ratio, the buffer status of the relay unit, the buffer status report of one or more remote units, the first buffer state of UL transmission of the relay unit, the second buffer state of SL transmission and reception of the relay unit, the expected payload size of UL transmission data and SL transmission and reception data of the relay unit, the traffic type, the traffic period, the traffic priority, the traffic payload size, or some combination thereof.