Prioritized messaging and resource selection in vehicle-to-vehicle (V2V) sidelink communication

1. A method, comprising:

a base station,

allocating a resource pool of physical resource blocks (PRBs) and sub-frames for sidelink transmissions;

decoding, from a user equipment (UE), an uplink control message that indicates that the UE requests a sidelink transmission of a prioritized message in a transmission period;

selecting, for the sidelink transmission of the prioritized message, one or more PRBs of the resource pool and one or more sub-frames of the resource pool; and

encoding, for transmission to the UE and to at least one other target UE in a cell area, a downlink control message that indicates selected PRBs, selected sub-frames, and a mute operation for the transmission period for the at least one other target UE to enable the sidelink transmission of the prioritized message.

2. The method of claim 1 ,

wherein the mute operation is for a finite duration.

3. The method of claim 1 ,

wherein the mute operation indicates that the at least one other target UE is to mute sidelink transmissions in the selected PRBs in the selected sub-frames.

4. The method of claim 1 ,

wherein the downlink control message is a first downlink control message, and wherein the method further comprises the base station:

encoding, for transmission, a second downlink control message that indicates the PRBs of the resource pool and the sub-frames of the resource pool.

5. The method of claim 1 ,

wherein the downlink control message is a medium access control (MAC) control element (CE) included in a physical downlink shared channel (PDSCH).

6. The method of claim 1 ,

wherein the downlink control message is a physical downlink control channel (PDCCH), and

wherein the PDCCH includes a downlink control information (DCI) that includes the selected PRBs and the selected sub-frames.

7. The method of claim 1 ,

wherein the downlink control message is a broadcast system information block (SIB).

8. The method of claim 1 ,

wherein the uplink control message is included in a physical uplink shared channel (PUSCH), or

wherein the uplink control message is a physical uplink control channel (PUCCH).

9. The method of claim 1 ,

wherein the uplink control message indicates one or more of: a transmission period for the sidelink transmission of the prioritized message, a number of PRBs for the sidelink transmission of the prioritized message, and a buffer status report, and

wherein the method further comprises the base station selecting the PRBs and the sub-frames for the sidelink transmission of the prioritized message based at least partly on the uplink control message.

10. The method of claim 1 ,

wherein the base station is arranged to operate in accordance with a Third Generation Partnership Project (3GPP) protocol, and

wherein the base station is configured for mode-3 operation, wherein the base station is to select the PRBs and the sub-frames of the resource pool for the sidelink transmissions.

11. The method of claim 1 ,

wherein the base station is arranged to operate in accordance with a Third Generation Partnership Project (3GPP) protocol,

wherein the uplink control message is received over an uplink Uu interface, and

wherein the downlink control message is transmitted over a downlink Uu interface.

12. A base station, comprising:

a memory; and

at least one processor in communication with the memory and configured to cause the base station to:

allocate a resource pool of physical resource blocks (PRBs) and sub-frames for sidelink transmissions;

decode, from a user equipment (UE), an uplink control message that indicates that the UE requests a sidelink transmission of a prioritized message in a transmission period;

select, for the sidelink transmission of the prioritized message, one or more PRBs of the resource pool and one or more sub-frames of the resource pool; and

encode, for transmission to the UE and to at least one other target UE in a cell area, a downlink control message that indicates selected PRBs, selected sub-frames, and a mute operation for the transmission period indicating that the at least one other target UE is to mute sidelink transmissions in the selected PRBs in the selected sub-frames to enable the sidelink transmission of the prioritized message.

13. The base station of claim 12 ,

wherein the mute operation is for a finite duration.

14. The base station of claim 12 ,

wherein the downlink control message is a first downlink control message,

wherein the uplink control message is a first uplink control message, and

wherein the at least one processor is further configured to cause the base station to:

encode, for transmission, a second downlink control message that instructs the UE to sense a sidelink channel in accordance with one or more channel sense parameters; and

decode, from the UE, a second uplink control message that indicates one or more results of a sense operation in accordance with the channel sense parameters.

15. The base station of claim 12 ,

wherein the downlink control message is a first downlink control message, and

wherein the at least one processor is further configured to cause the base station to:

encode, for transmission, a second downlink control message that instructs the UE to perform radio-layer measurements within sidelink resource pools to determine candidate resources available for sidelink transmission.

16. The base station of claim 15 ,

wherein the second downlink control message is a radio resource control (RRC) message, and

wherein the RRC message includes one or more triggering conditions for measurement and reporting of results by the UE.

17. The base station of claim 16 ,

wherein the triggering conditions are based on one or more of:

a received power threshold or a reference signal received power (RSRP) threshold for detected sidelink transmissions, or

a priority threshold for detected sidelink transmissions.

18. The base station of claim 16 ,

wherein the RRC message indicates that the UE is to use a reporting format that indicates, from the sidelink resource pools:

recommended resources for allocation for sidelink transmissions, or

resources to refrain from allocation for the sidelink transmissions.

19. An apparatus comprising:

a memory; and

at least one processor in communication with the memory and configured to cause a user equipment (UE) to:

determine that a prioritized message is to be transmitted to another UE over sidelink in a transmission period;

select one or more physical resource blocks (PRBs) and one or more sub-frames to be used for transmission of the prioritized message over the sidelink, wherein the PRBs and sub-frames are included in a resource pool of candidate PRBs and candidate sub-frames;

encode, for transmission to at least one other target UE in a cell area, a sidelink control message that indicates selected PRBs, selected sub-frames, and a mute operation for the transmission period for the at least one other target UE to enable sidelink transmission of the prioritized message; and

encode the prioritized message for transmission in the selected PRBs in the selected sub-frames.

20. The apparatus of claim 19 ,

wherein the at least one processor is further configured to:

determine that the prioritized message is to be transmitted over the sidelink based at least partly on an indicator generated by an application layer of the UE.