Sidelink signal measurement and resource selection in vehicle-to-everything communications

Patent metadata

Field	Value
Publication number	US-11357015-B2
Application number	US-201816228200-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Dec 22, 2017
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

Aspects of the present disclosure implement techniques that allow a vehicle performing V2X communications to provide more accurate S-RSSI measurements and CBR calculations for use in channel selection and congestion control. Techniques may include measuring a sidelink received signal strength indicator (S-RSSI) for each of a plurality of sub-channels, determining one or more signal impairment adjustment factors based on the S-RSSI for each of the plurality of sub-channels, calculating a channel busy ratio (CBR) for the plurality of sub-channels based on the one or more signal impairment adjustment factors, and initiating communication with at least one of the plurality of sub-channels based on at least the CBR.

First claim

What is claimed is:

1. A method of controlling wireless communications, comprising:
measuring a sidelink received signal strength indicator (S-RSSI) for each of a plurality of sub-channels;
changing a value of at least one S-RSSI for at least one sub-channel of the plurality of sub-channels based, at least in part, on at least one S-RSSI adjustment value for the at least one sub-channel, the at least one S-RSSI adjustment value being based on, at least in part, a signal noise corresponding to the at least one sub-channel;
determining one or more signal impairment adjustment factors based on the S-RSSI for each of the plurality of sub-channels;
calculating a channel busy ratio (CBR) for each of the plurality of sub-channels based on the one or more signal impairment adjustment factors for each of the plurality of sub-channels; and
initiating communication via at least the at least one sub-channel of the plurality of sub-channels based, at least in part, on at least the CBR for each of the plurality of sub-channels,
wherein determining one or more signal impairment adjustment factors further comprises identifying one or more of the S-RSSI for each of the plurality of sub-channels as including measurement noise from one or more of DC power, signal interference, signal image, or signal leakage.

2. The method of claim 1 , further comprising:
wherein determining the one or more signal impairment adjustment factors comprises determining one or more threshold adjustment values based on at least one of the S-RSSI for each of the plurality of sub-channels;
changing one or more CBR thresholds used in calculating the CBR for each of the plurality of sub-channels by a corresponding one of the one or more threshold adjustment values to define one or more adjusted CBR thresholds;
wherein calculating the CBR further comprises using the one or more adjusted CBR thresholds; and
wherein initiating communication is further based on the CBR calculated using the one or more adjusted CBR thresholds.

3. The method of claim 2 ,
wherein calculating the CBR further comprises comparing the S-RSSI for each of the of the plurality of sub-channels to the corresponding one of the one or more adjusted CBR thresholds to determine if the respective sub-channel is busy or not busy; and
wherein initiating communication further comprises initiating based on the CBR determined based on the corresponding one of the one or more adjusted CBR thresholds.

4. The method of claim 2 , wherein changing the one or more CBR thresholds comprises changing a single CBR threshold that is used to calculate the CBR across all of the plurality of sub-channels.

5. The method of claim 2 , wherein changing the one or more CBR thresholds comprises changing a plurality of CBR thresholds, each corresponding to one of the plurality of sub-channels.

6. The method of claim 2 , wherein determining the one or more threshold adjustment values based on at least one of the S-RSSI for each of the plurality of sub-channels comprises:
determining whether at least one of the measured S-RSSIs satisfy a measurement threshold; and
increasing or decreasing the one or more CBR thresholds by the one or more threshold adjustment values based on whether the at least one of the measured S-RSSIs satisfy a measurement threshold.

7. The method of claim 2 , wherein determining the one or more threshold adjustment values based on at least one of the S-RSSI for each of the plurality of sub-channels comprises:
determining a measured maximum one of the S-RSSIs;
determining a unit value of the one or more threshold adjustment values based on the maximum one of the S-RSSIs; and
increasing or decreasing the one or more CBR thresholds by the unit value of the one or more threshold adjustment values.

8. The method of claim 2 , wherein determining the one or more threshold adjustment values based on at least one of the S-RSSI for each of the plurality of sub-channels comprises:
calculating a statistic of the S-RSSIs; and
changing the CBR threshold based, at least in part, on the statistic.

9. The method of claim 2 , wherein the CBR threshold for each of the plurality of sub-channels is defined by a function:
CBR threshold=max S-RSSI+/−X,

wherein the max S-RSSI is a maximum one of the S-RSSIs and wherein the X is the one or more signal impairment adjustment factors.

10. The method of claim 2 , wherein the one or more threshold adjustment values are determined based on one or more of Semi-Persistent Scheduling (SPS) information, Physical Sidelink Control Channel (PSCCH) decoding information, or Physical Sidelink Shared Channel (PSSCH) decoding information.

11. The method of claim 1 , further comprising:
comparing the S-RSSI for each of the of the plurality of sub-channels to a corresponding CBR threshold for each of the plurality of sub-channels to determine if the respective sub-channel is busy or not busy; and
wherein initiating the communication via the at least one of the plurality of sub-channels based on at least the CBR further comprises initiating communication via the at least one sub-channel based at least in part a determination that the at least one sub-channel is not busy.

12. The method of claim 1 , wherein initiating communication via the at least one sub-channel further comprises performing a resource selection or performing a congestion control procedure for the at least one sub-channel.

13. An apparatus for controlling wireless communications, comprising:
a transceiver;
a memory; and
a processor coupled with the transceiver and the memory and configured to perform operations comprising:
measure a sidelink received signal strength indicator (S-RSSI) for each of a plurality of sub-channels;
change a value of at least one S-RSSI for at least one sub-channel of the plurality of sub-channels based, at least in part, on at least one S-RSSI adjustment value for the at least one sub-channel, the at least one S-RSSI adjustment value being based on, at least in part, a signal noise corresponding to the at least one sub-channel;
determine one or more signal impairment adjustment factors based on the S-RSSI for each of the plurality of sub-channels;
calculate a channel busy ratio (CBR) for each of the plurality of sub-channels based on the one or more signal impairment adjustment factors for each of the plurality of sub-channels; and
initiate communication by the transceiver via at least the at least one sub-channel of the plurality of sub-channels based, at least in part, on at least the CBR for each of the plurality of sub-channels,

wherein the processor is configured to determine the one or more signal impairment adjustment factors by identifying one or more of the S-RSSI for each of the plurality of sub-channels as including measurement noise from one or more of DC power, signal interference, signal image, or signal leakage.

14. The apparatus of claim 13 , wherein the processor is configured to determine the one or more signal impairment adjustment factors by determining one or more threshold adjustment values based on at least one of the S-RSSI for each of the plurality of sub-channels; and
the processor is further configured to change one or more CBR thresholds used in calculating the CBR for each of the plurality of sub-channels by a corresponding one of the one or more threshold adjustment values to define one or more adjusted CBR thresholds;
wherein the processor is configured to calculate the CBR using the one or more adjusted CBR thresholds; and
wherein the processor is configured to initiate the communication based on the CBR calculated using the one or more adjusted

Assignees

• Qualcomm Inc

Inventors

• Park Cheol Hee
• Iyer Ashish Shankar
• Santhanam Arvind Vardarajan
• Sheng Hongsan
• Rao Subramanya
• Lu Feng
• Rongala Santosh Kumar
• Sheng Li
• Wang Yuanbo

Classifications

• H04W72/542 Primary

  using measured or perceived quality · CPC title

• H04W72/52

  based on load · CPC title

• H04B17/318 Primary

  Received signal strength · CPC title

• H04W24/08

  Testing, {supervising or monitoring} using real traffic · CPC title

• H04L43/16

  Threshold monitoring · CPC title