Schemes to avoid periodic resource collisions
Systems, methods and circuitries are provided for performing UE autonomous selection in a vehicle-to-anything (V2X) communication environment, that includes one or more processors configured to schedule resources for discontinuous periodic transmission having a scheduled discontinuous time period in which scheduled resources are not transmitted. The one or more processors are further configured to perform a monitoring operation at the scheduled discontinuous time period, the monitoring operation comprising a monitoring for a collision of scheduled resources of the evaluating UE with scheduled resources of a competing UE, and selectively perform a corrective action when a collision of scheduled resources of the evaluating UE with scheduled resources of the competing UE is detected during the monitoring operation.
1. An evaluating user equipment (UE), comprising:
memory;
one or more processors communicatively coupled to the memory and configured to cause the evaluating UE to:
schedule periodic resources for a discontinuous periodic transmission of the evaluating UE, wherein the periodic resources includes transmission time periods for data transmission and a discontinuous time period in which a discontinuous resource of the periodic resources is used for monitoring for a collision of the periodic resources with scheduled resources of a competing UE, wherein the discontinuous resource is selected based on a probability value; and
perform a corrective action when the collision is detected,
wherein the probability value is a low probability value smaller than a nominal probability value if a priority of the data transmission is greater than a predefined threshold.
2. The evaluating UE of claim 1 , wherein multiple resources are scheduled per period for the discontinuous periodic transmission, and the probability value is independently applied to each of the multiple resources.
3. The evaluating UE of claim 1 , wherein the probability value is a preconfigured or configured per resource pool.
4. The evaluating UE of claim 1 , wherein, responsive to a resource reservation period (RRP) of the evaluating UE being an integer multiple of a RRP of the competing UE and the collision being detected,
sending a message to the competing UE to skip data transmission on scheduled resources of the competing UE that collide with the periodic resources.
5. The evaluating UE of claim 1 ,
wherein the probability value is a high probability value greater than the nominal probability value if the priority of the data transmission is greater than the predefined threshold.
6. The evaluating UE of claim 1 , wherein when scheduling the periodic resources, the one or more processors are configured to:
set a resource reservation period (RRP) field of a sidelink control information (SCI) message of the evaluating UE to a new value that doubles a previous RRP field value of the evaluating UE, responsive to a determination that a next period will be the discontinuous time period.
7. The evaluating UE of claim 1 , wherein when scheduling the periodic resources, the one or more processors are configured to:
set a bit in a sidelink control information (SCI) message to a predetermined value to indicate a next period as the discontinuous time period.
8. The evaluating UE of claim 1 , wherein when performing the corrective action, the one or more processors are configured to:
evaluate whether a resource reservation period (RRP) of the competing UE is an integer multiple of the RRP of the evaluating UE; and
stop the discontinuous periodic transmission only on resources of the periodic resources where the collision occurs, when the RRP of the competing UE is an integer multiple of the RRP of the evaluating UE.
9. A method of performing user equipment (UE) autonomous selection in an evaluating UE within a vehicle-to-anything (V2X) communication environment, the method comprising:
scheduling periodic resources for a discontinuous periodic transmission, wherein the periodic resources include a discontinuous time period in which a discontinuous resource of the periodic resources is not used for data transmission by the evaluating UE, wherein the discontinuous resource is selected based on a periodicity of the discontinuous time period;
at the discontinuous time period, monitoring for a collision of the periodic resources with scheduled resources of a competing UE; and
performing a corrective action when the collision is detected,
wherein the periodicity is randomly selected from a set of (pre)configured periods including prime numbers or mutually prime numbers.
10. The method of claim 9 , further comprising setting a resource reservation period (RRP) field of a sidelink control information (SCI) message of the evaluating UE to a new value that doubles a previous RRP field value of the evaluating UE, responsive to a determination that a next period will be the discontinuous time period.
11. The method of claim 9 , wherein the periodicity is randomly selected from a set of preconfigured or configured periods.
12. The method of claim 9 , wherein the periodicity depends upon a data priority associated with the scheduled periodic resources.
13. The method of claim 9 , wherein when performing the corrective action, the method comprises:
stopping the discontinuous periodic transmission on the scheduled periodic resources and perform a re-selection operation to reschedule resources for the discontinuous periodic transmission on different reserved resources, responsive to an evaluation that a resource reservation period (RRP)—of the competing UE is identical to an RRP of the evaluating UE.
14. The method of claim 9 , further comprising taking no corrective action responsive to a determination that a data priority of the evaluating UE is greater than a data priority of the competing UE.
15. A non-transitory computer readable medium containing instructions, wherein such instructions when executed by one or more processors is configured to perform a method of performing user equipment (UE) autonomous selection in an evaluating UE, the method comprising:
scheduling periodic resources for a discontinuous periodic transmission, wherein the periodic resources includes transmission time periods for data transmission and a discontinuous time period for monitoring for a collision of the periodic resources with scheduled resources of a competing UE;
responsive to a resource reservation period (RRP) of the competing UE being an integer multiple of a RRP of the evaluating UE and the collision being detected, performing a corrective action to stop the data transmission on resources of the periodic resources where the collision occurs and still perform the data transmission on remaining resources of the periodic resources; and
responsive to the RRP of the evaluating UE being an integer multiple of the RRP of the competing UE and the collision being detected, sending a message to the competing UE to skip data transmission on scheduled resources of the competing UE that collide with the periodic resources.
16. The non-transitory computer readable medium of claim 15 , wherein when monitoring for the collision, the method comprises:
evaluating one or more relevant frequency channels for sidelink control information (SCI) messages of one or more competing UEs; and
for each SCI message detected in the relevant frequency channels, determining whether any scheduled resources of the one or more competing UEs collide with the periodic resources.
17. The non-transitory computer readable medium of claim 15 , wherein the discontinuous periodic transmission is configured or preconfigured per resource pool.
18. The non-transitory computer readable medium of claim 17 , wherein the method comprises: taking no corrective action if a data priority of the evaluating UE is greater than a data priority of the competing UE.
19. The non-transitory computer readable medium of claim 15 , wherein, responsive to a determination that a next period will be the discontinuous time period, set a RRP field of a sidelink control information (SCI) message of the evaluating UE to a new value that doubles a previous RRP field value of the evaluating UE or set a bit in a sidelink control information (SCI) message to a predetermined value to indicate a next period as the discontinuous time period.
20. The non-transitory computer readable medium of claim 15 , wherein, responsive to the RRP of the evaluating UE being an integer multiple of the RRP of the competing UE and the collision being detected,
stopping the data transmission and performing a re-selection operation to reschedule resources for the discontinuous periodic transmission on different resources.