Reliable low latency wireless transfer of virtual reality headset sensor information
Certain aspects of the present disclosure generally relate to wireless communications and, more particularly, to wireless transfer of sensor information between a station (e.g., a VR headset) and an access point (e.g., a server).
1. An apparatus for wireless communications, comprising:
a processing system configured to stream media to a first station over a wireless medium; and
an interface configured to obtain sensor frames having sensor data therein from the first station, wherein the processing system is further configured to:
change content of the media streamed to the first station based on the sensor data; and
take one or more actions to give the sensor frames higher priority relative to other traffic on the wireless medium, wherein:
the sensor frames are obtained from the first station periodically in accordance with a scheduled sensor frame transmission time (SFTT); and
the one or more actions comprise truncating a transmit opportunity (TxOP) for frames containing media content that overlaps with the SFTT.
2. The apparatus of claim 1 , wherein the higher priority comprises lower channel access time relative to other frames on the wireless medium.
3. The apparatus of claim 1 , wherein the media content comprises at least one of video or audio.
4. The apparatus of claim 1 , wherein the sensor data comprises at least one of position or orientation of the first station.
5. The apparatus of claim 1 , wherein the processing system is further configured to synchronize the scheduled SFTT with the first station via a time synchronization function (TSF).
6. The apparatus of claim 1 , wherein the one or more actions further comprise outputting a frame for transmission to set a network allocation vector (NAV) with a duration to cover transmission of a sensor frame by the first station.
7. The apparatus of claim 1 , wherein the processing system is further configured to resume outputting frames containing media content for transmission to the first station after truncating the TxOP and after receiving a sensor frame.
8. The apparatus of claim 7 , wherein the processing system is further configured to:
perform channel access of the wireless medium a programmable time after the SFTT, before resuming outputting the frames containing media content.
9. The apparatus of claim 8 , wherein the channel access is performed based on at least one of a Point coordination function (PCF) Interframe Spacing (PIFS) or a backoff timer.
10. The apparatus of claim 1 , wherein:
the processing system is further configured to stream media to at least a second station over the wireless medium; and
the interface is further configured to obtain sensor frames having sensor data therein from the second station, wherein the sensor frames are obtained periodically from the first and second stations in accordance with first and second SFTTs.
11. The apparatus of claim 10 , wherein the processing system is further configured to configure the first and second stations so the first and second SFTTs are offset in time.
12. The apparatus of claim 1 , wherein:
the processing system is further configured to periodically output polling frames for transmission to the first station in accordance with the SFTT;
the sensor data is obtained via the sensor frames after transmission of one or more of the polling frames.
13. The apparatus of claim 12 , wherein the one or more actions further comprise sending a frame to set a network allocation vector (NAV) with a duration to cover transmission of a sensor frame by the first station.
14. The apparatus of claim 12 , wherein the processing system is further configured to resume streaming media content after truncating the TxOP and after receiving a sensor frame.
15. The apparatus of claim 14 , wherein the processing system is further configured to:
perform channel access of the wireless medium a programmable time after the SFTT, before resuming streaming media content.
16. The apparatus of claim 15 , wherein the channel access is performed based on at least one of a point coordination function interframe spacing (PIFS), distributed coordination function interframe spacing (DIFS) or a backoff timer.
17. The apparatus of claim 12 , wherein:
the processing system is further configured to stream media to at least a second station over the wireless medium; and
the interface is further configured to obtain sensor frames having sensor data therein from the second station, wherein the sensor frames are obtained periodically from the first and second stations in response to the polling frames being periodically outputted for transmission in accordance with first and second SFTTs.
18. An apparatus for wireless communications by a first station, comprising:
an interface configured to obtain media streamed from an access point over a wireless medium; and
a processing system configured to periodically output sensor data for transmission to the access point via sensor frames in accordance with a scheduled sensor frame transmission time (SFTT), wherein:
content of the media streamed to the first station changes based on the sensor data;
the sensor data is output for transmission with higher priority relative to other traffic on the wireless medium; and
the sensor data is output for transmission based on a truncated transmit opportunity (TxOP) for frames containing media content that overlaps with the SFTT.
19. The apparatus of claim 18 , wherein the sensor data comprises at least one of position or orientation of the first station.
20. The apparatus of claim 18 , wherein the processing system is further configured to synchronize the scheduled SFTT with the access point via a time synchronization function (TSF).
21. The apparatus of claim 18 , wherein the processing system is further configured to maintain a timer that triggers an SFTT event after which the first station sends a sensor frame.
22. The apparatus of claim 21 , wherein:
the processing system is further configures to perform channel access of the wireless medium after the truncated TxOP; and
the channel access is performed based on at least one of a point coordination function interframe spacing (PIFS), distributed coordination function interframe spacing (DIFS) or a backoff timer.
23. The apparatus of claim 18 , wherein the processing system is further configured to:
ignore a frame sent by the access point to set a network allocation vector (NAV) with a duration to cover transmission of a sensor frame by the first station.
24. The apparatus of claim 18 , wherein:
the interface is further configured to periodically obtain polling frames from the access point in accordance with the SFTT; and
the sensor data is output for transmission via sensor frames in response to the polling frames.
25. An access point, comprising:
a processing system configured to stream media to a first station over a wireless medium; and
a receiver configured to receive sensor frames having sensor data therein from the first station, wherein the processing system is further configured to:
change content of the media streamed to the first station based on the sensor data; and
take one or more actions to give the sensor frames higher priority relative to other traffic on the wireless medium, wherein:
the sensor frames are obtained from the first station periodically in accordance with a scheduled sensor frame transmission time (SFTT); and
the one or more actions comprise truncating a transmit opportunity (TxOP) for frames containing media content that overlaps with the SFTT.
26. A first station, comprising:
a receiver configured to receive media streamed from an access point over a wireless medium; and
a processing system configured to periodically output sensor data for transmission to the access point via sensor frames in accordance with a scheduled sensor frame transmission time (SFTT), wherein:
content of the media streamed to the first station changes based on the sensor data;
the sensor data is output for transmission with higher priority relative to other traffic on the wireless medium; and
the sensor data is output for transmission based on a truncated transmit opportunity (TxOP) for frames containing media content that overlaps with the SFTT.