Pre-emption, congestion control, and Tx/Rx alignment for NR V2X UE with limited power
A method and apparatus are provided for pre-emption, congestion control, and Tx/Rx alignment for use by a partial sensing UE. A method includes measuring resources within a first window; determining a number of the measured resources having an RSSI greater than a first threshold; determining a CBR based on the measured number of resources; and determining a CR limit based on the determined CBR and transmission priority. Determining the CBR based on the measured number of resources includes comparing a total number of measured resources within the first window to a second threshold; in response to the total number of measured resources being less than the second threshold, determining the CBR as a pre-configured CBR; and in response to the total number of measured resources being greater than or equal to the second threshold, determining the CBR based on a ratio of the number of the measured resources having the RSSI greater than the first threshold to the total number of measured resources within the first window.
1. A method performed by a partial sensing user equipment (UE), the method comprising:
measuring resources within a first window;
determining a number of the measured resources having a received signal strength indication (RSSI) greater than a first threshold;
determining a channel busy ratio (CBR) based on the measured number of resources; and
determining a channel occupancy ratio (CR) limit based on the determined CBR and transmission priority,
wherein determining the CBR based on the measured number of resources comprises:
comparing a total number of measured resources within the first window to a second threshold; and
performing at least one of (a) or (b):
(a) in response to the total number of measured resources within the first window being less than the second threshold, determining the CBR as a pre-configured CBR, and
(b) in response to the total number of measured resources within the first window being greater than or equal to the second threshold, determining the CBR based on a ratio of the number of the measured resources having the RSSI greater than the first threshold to the total number of measured resources within the first window.
2. The method of claim 1 , further comprising:
measuring a CR of resources within a second window;
comparing the measured CR to the determined CR limit; and
performing a transmission, in response to the measured CR being less than the determined CR limit.
3. The method of claim 1 , wherein the pre-configured CBR is dynamically selected from among a plurality of CBR values preconfigured for a resource pool.
4. The method of claim 3 , wherein the wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a priority of the partial sensing UE.
5. The method of claim 3 , wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a last measured CBR.
6. The method of claim 1 , wherein the determined CBR is valid for a pre-configured duration.
7. A partial sensing user equipment (UE), the partial sensing UE comprising:
a transceiver; and
a processor configured to:
measure resources within a first window;
determine a number of the measured resources having a received signal strength indication (RSSI) greater than a first threshold;
determine a channel busy ratio (CBR) based on the measured number of resources; and
determine a channel occupancy ratio (CR) limit based on the determined CBR and transmission priority,
wherein the processor is further configured to determine the CBR based on the measured number of resources by:
comparing a total number of measured resources within the first window to a second threshold; and
performing at least one of (a) or (b):
(a) in response to the total number of measured resources within the first window being less than the second threshold, determining the CBR as a pre-configured CBR, and
(b) in response to the total number of measured resources within the first window being greater than or equal to the second threshold, determining the CBR based on a ratio of the number of the measured resources having the RSSI greater than the first threshold to the total number of measured resources within the first window.
8. The partial sensing UE of claim 7 , wherein the processor is further configured to:
measure a CR of resources within a second window;
compare the measured CR to the determined CR limit; and
perform a transmission, via the transceiver, in response to the measured CR being less than the determined CR limit.
9. The partial sensing UE of claim 7 , wherein the pre-configured CBR is dynamically selected from among a plurality of CBR values preconfigured for a resource pool.
10. The partial sensing UE of claim 9 , wherein the wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a priority of the partial sensing UE.
11. The partial sensing UE of claim 9 , wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a last measured CBR.
12. The partial sensing UE of claim 7 , wherein the determined CBR is valid for a pre-configured duration.
13. A partial sensing user equipment (UE), the partial sensing UE comprising:
a processor; and
a non-transitory computer readable storage medium storing instructions that, when executed, cause the processor to:
measure resources within a first window;
determine a number of the measured resources having a received signal strength indication (RSSI) greater than a first threshold;
determine a channel busy ratio (CBR) based on the measured number of resources; and
determine a channel occupancy ratio (CR) limit based on the determined CBR and transmission priority,
wherein the instructions, when executed, further cause the processor to:
compare a total number of measured resources within the first window to a second threshold; and
perform at least one of (a) or (b):
(a) in response to the total number of measured resources within the first window being less than the second threshold, determine the CBR as a pre-configured CBR, and
(b) in response to the total number of measured resources within the first window being greater than or equal to the second threshold, determine the CBR based on a ratio of the number of the measured resources having the RSSI greater than the first threshold to the total number of measured resources within the first window.
14. The partial sensing UE of claim 13 , wherein the instructions, when executed, further cause the processor to:
measure a CR of resources within a second window;
compare the measured CR to the determined CR limit; and
perform a transmission, in response to the measured CR being less than the determined CR limit.
15. The partial sensing UE of claim 13 , wherein the pre-configured CBR is dynamically selected from among a plurality of CBR values preconfigured for a resource pool.
16. The partial sensing UE of claim 15 , wherein the wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a priority of the partial sensing UE.
17. The partial sensing UE of claim 15 , wherein the pre-configured CBR is dynamically selected from among the plurality of CBR values based on a last measured CBR.
18. The partial sensing UE of claim 13 , wherein the determined CBR is valid for a pre-configured duration.