Aperiodic indications for beam failure recovery
A wireless device receives one or more messages comprising one or more configuration parameters. The one or more configuration parameters indicate: a value of a timer for controlling a radio link failure indication based on a beam failure recovery procedure, and a first number of out-of-synchronization indications. The wireless device determines a second number of out-of-synchronization indications. The timer associated with the value is started in response to the second number being equal to the first number of out-of-synchronization indications. A first failure of the beam failure recovery procedure is determined. The first failure is ignored, by not causing a radio link failure, in response to the timer running when the first failure is determined. A second failure of the beam failure recovery procedure is determined. A radio link failure is indicated in response to the timer being expired when the second failure is determined.
1. A method comprising:
receiving, by a wireless device, one or more messages comprising one or more configuration parameters indicating:
a value of a timer for controlling a radio link failure indication based on a beam failure recovery procedure; and
a first number of out-of-synchronization indications;
determining, by the wireless device, a second number of out-of-synchronization indications;
starting the timer associated with the value in response to the second number being equal to the first number of out-of-synchronization indications;
determining a first failure of the beam failure recovery procedure;
ignoring the first failure by not causing a radio link failure in response to the timer running when the first failure is determined;
determining a second failure of the beam failure recovery procedure; and
indicating a radio link failure in response to the timer being expired when the second failure is determined.
2. The method of claim 1 , wherein the determining the first failure of the beam failure recovery procedure comprises a preamble counter being equal to a maximum number of preamble transmissions.
3. The method of claim 1 , wherein the determining the first failure of the beam failure recovery procedure comprises an expiry of a beam failure recovery timer.
4. The method of claim 3 , wherein the one or more configuration parameters further indicate the beam failure recovery timer.
5. The method of claim 1 , wherein the determining the second failure of the beam failure recovery procedure comprises a preamble counter being equal to a maximum number of preamble transmissions.
6. The method of claim 1 , wherein the determining the second failure of the beam failure recovery procedure comprises an expiry of a beam failure recovery timer.
7. The method of claim 6 , wherein the one or more configuration parameters further indicate the beam failure recovery timer.
8. The method of claim 1 , wherein the one or more configuration parameters further indicate a maximum number of preamble transmissions for the beam failure recovery procedure.
9. The method of claim 1 , further comprising initiating the beam failure recovery procedure based on detecting a beam failure.
10. The method of claim 9 , further comprising starting a beam failure recovery timer in response to the initiating the beam failure recovery procedure.
11. The method of claim 9 , wherein the detecting the beam failure comprises assessing that one or more first reference signals have a radio quality lower than a first threshold.
12. The method of claim 11 , wherein the one or more configuration parameters further indicate the one or more first reference signals.
13. The method of claim 11 , wherein the first threshold is based on a hypothetical block error rate.
14. The method of claim 9 , wherein the initiating the beam failure recovery procedure further comprising transmitting at least one preamble via at least one random access channel resource in response to selecting a selected reference signal.
15. The method of claim 14 , further comprising incrementing a preamble counter in response to the transmitting the at least one preamble.
16. The method of claim 14 , wherein the selected reference signal has a radio quality higher than a second threshold.
17. The method of claim 1 , wherein the one or more configuration parameters further indicate:
one or more second reference signals; and
one or more beam failure recovery request resources.
18. The method of claim 17 , wherein the one or more configuration parameters further indicate an association between each of the one or more second reference signals to a different one of the one or more beam failure recovery request resources.
19. The method of claim 17 , wherein the beam failure recovery procedure further comprises selecting a selected RS of the one or more second reference signals associated with a beam failure recovery request resource of the one or more beam failure recovery request resources.
20. The method of claim 19 , wherein the beam failure recovery request resource comprises at least one preamble and at least one random access channel resource.