Device/UE-oriented beam recovery and maintenance mechanisms
Aspects of this disclosure provide techniques for detecting and recovering from beam-failure events. In some embodiments, motion sensor information generated by motion sensors on a UE is used to detect, predict, and/or recover from a beam failure event that results, or would otherwise result, from movement of the UE. The motion sensor information may be used to adjust a current beam direction used by the UE to transmit or receive a signal, or to determine a recommendation for adjusting a current beam direction of the base station. The motion sensor information may be generated by any sensor that detects a movement of the UE, such as a gyroscope, an accelerometer, a magnetometer, a global positioning system (GPS) sensor, a global navigation satellite system (GNSS) sensor, or any other device that detects a change in position/orientation of the UE.
1. A method comprising:
receiving, by a user equipment (UE), one or more downlink reference signals over a first carrier frequency;
detecting, by the UE, a UE-initiated beam failure event associated with one or more beams on the first carrier frequency within a time-out period based on reception of the one or more downlink reference signals over the first carrier frequency; and based thereon
transmitting, by the UE, a physical random access channel (PRACH) transmission indicating the UE-initiated beam failure event over a second carrier frequency that is different than the first carrier frequency.
2. The method of claim 1 , wherein the one or more downlink reference signals are received over physical downlink control channels (PDCCHs), physical downlink shared channel (PDSCHs), or combinations thereof.
3. The method of claim 1 , wherein the PRACH transmission further includes a UE-initiated recommendation for recovering from the UE-initiated beam failure event.
4. The method of claim 3 , wherein the UE-initiated recommendation includes a recommendation for changing a beam direction of a base station being used by the base station for transmitting or receiving data to or from the UE, respectively.
5. The method of claim 4 , wherein the recommendation for changing the beam direction of the base station is indicated by an index in the UE-initiated recommendation.
6. The method of claim 3 , wherein the UE-initiated recommendation includes a recommendation to initiate a beam management procedure.
7. A user equipment (UE) comprising:
a processor; and
a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
receive one or more downlink reference signals over a first carrier frequency using one or more receive beams of the UE;
detect a UE-initiated beam failure event associated with one or more beams on the first carrier frequency within a time-out period based on reception of the downlink reference signals over the first carrier frequency; and based thereon
transmit a physical random access channel (PRACH) transmission indicating the UE-initiated beam failure event over a second carrier frequency that is different than the first carrier frequency.
8. The method of claim 1 , wherein detecting the UE-initiated beam failure event comprises:
detecting, by the UE, the UE-initiated beam failure event upon determining that none of the one or more downlink reference signals received prior to expiration of the time-out period have a received signal quality exceeding a quality or power threshold.
9. The UE of claim 7 , wherein the instructions to detect the UE-initiated beam failure event include instructions to:
detect, by the UE, the UE-initiated beam failure event upon determining that none of the one or more downlink reference signals received prior to expiration of the time-out period have a received signal quality exceeding a quality or power threshold.
10. The UE of claim 7 , wherein the one or more downlink reference signals are received over physical downlink control channels (PDCCHs), physical downlink shared channel (PDSCHs), or combinations thereof.
11. The UE of claim 7 , wherein the PRACH transmission further includes a UE-initiated recommendation for recovering from the UE-initiated beam failure event.
12. The UE of claim 11 , wherein the UE-initiated recommendation includes a recommendation for changing a beam direction of a base station being used by the base station for transmitting or receiving data to or from the UE, respectively.
13. The UE of claim 12 , wherein the recommendation for changing the beam direction of the base station is indicated by an index in the UE-initiated recommendation.
14. The UE of claim 11 , wherein the UE-initiated recommendation includes a recommendation to initiate a beam management procedure.
15. The UE of claim 7 , wherein the PRACH transmission indicating the UE-initiated beam failure event is transmitted using a transmit beam of the UE that corresponds to a receive beam of the UE that was used to receive at least one of the one or more downlink reference signals.
16. The method of claim 1 , wherein the PRACH transmission indicating the UE-initiated beam failure event is transmitted using a transmit beam of the UE that corresponds to a receive beam of the UE that was used to receive at least one of the one or more downlink reference signals.