Beam management and beam failure recovery in radio systems
A wireless device may detect a beam failure of a serving beam set. In response to detecting the beam failure, the wireless device may select a first candidate beam set from candidate beam sets based on a priority order of the candidate beam sets, wherein each candidate beam set, of the candidate beam sets, comprises reference signals (RSs). The wireless device may select a first candidate RS from candidate RSs associated with the first candidate beam set based on a channel quality of the first candidate RS being greater than a threshold. The wireless device may transmit a preamble associated with the first candidate RS for beam failure recovery.
1. A method comprising:
reporting, by a wireless device, a capability of the wireless device for multiple candidate beam set monitoring;
receiving, by the wireless device, a radio resource control (RRC) message comprising:
a serving beam set;
a plurality of candidate beam sets, wherein:
each candidate beam set, of the plurality of candidate beam sets, comprises a plurality of candidate beams; and
each of the plurality of candidate beams is associated with a corresponding one of a plurality of downlink (DL) candidate reference signals (RSs); and
a monitoring priority configuration of the plurality of candidate beam sets;
detecting, by the wireless device, a beam failure of the serving beam set;
selecting, in response to the detecting, a first candidate beam set from the plurality of candidate beam sets based on the monitoring priority configuration of the plurality of candidate beam sets;
selecting a first DL candidate RS from first DL candidate RSs associated with the selected first candidate beam set based on a channel quality of the first DL candidate RS being greater than a threshold; and
transmitting a preamble associated with the first DL candidate RS for beam failure recovery.
2. The method of claim 1 , wherein the RRC message further comprises an association between the preamble and the first DL candidate RSs.
3. The method of claim 1 , further comprising:
selecting, in response to the detecting and based on the monitoring priority configuration, a second candidate beam set from the plurality of candidate beam sets before the selection of the first candidate beam set; and
determining, based on monitoring the second candidate beam set, not to select a second DL candidate RS from second DL candidate RSs associated with the second candidate beam set,
wherein the selecting the first candidate beam set is in response to the determining not to select the second DL candidate RS.
4. The method of claim 3 , wherein the monitoring priority configuration indicates that a priority of the second candidate beam set is higher than a priority of the first candidate beam set.
5. The method of claim 1 , wherein the first DL candidate RSs comprise:
one or more synchronization signal physical broadcast channel blocks; or
one or more channel state information reference signals (CSI-RSs).
6. The method of claim 1 , wherein the detecting the beam failure comprises detecting that channel qualities of DL RSs in the serving beam set are less than a second threshold.
7. The method of claim 1 , wherein each candidate beam set of the plurality of candidate beam sets is associated with the plurality of DL candidate RSs.
8. The method of claim 1 , wherein:
the preamble is identified by a preamble resource associated with the first DL candidate RS; and
the preamble resource comprises at least one of:
a preamble index,
a transmission resource in frequency domain for the preamble, or
a transmission resource in a time domain for the preamble.
9. The method of claim 1 , wherein the selecting the first candidate beam set is further based on channel qualities of the candidate beam sets.
10. The method of claim 1 , further comprising monitoring the first candidate beam set, wherein the selecting the first DL candidate RS is based on the monitoring.
11. A wireless device comprising:
one or more processors; and
memory storing instructions that, when executed by the one or more processors, cause the wireless device to:
report a capability of the wireless device for multiple candidate beam set monitoring;
receive a radio resource control (RRC) message comprising:
a serving beam set;
a plurality of candidate beam sets, wherein:
each candidate beam set, of the plurality of candidate beam sets, comprises a plurality of candidate beams; and
each of the plurality of candidate beams is associated with a corresponding one of a plurality of downlink (DL) candidate reference signals (RSs); and
a monitoring priority configuration of the plurality of candidate beam sets;
detect a beam failure of the serving beam set;
select, in response to detecting the beam failure, a first candidate beam set from the plurality of candidate beam sets based on the monitoring priority configuration of the plurality of candidate beam sets, wherein the monitoring priority configuration indicates a monitoring priority order;
select a first DL candidate RS from first DL candidate RSs associated with the selected first candidate beam set based on a channel quality of the first DL candidate RS being greater than a threshold; and
transmit a preamble associated with the first DL candidate RS for beam failure recovery.
12. The wireless device of claim 11 , wherein the RRC message further comprises an association between the preamble and the first DL candidate RSs.
13. The wireless device of claim 11 , wherein the instructions further cause the wireless device to:
select, in response to detecting the beam failure and based on the monitoring priority configuration, a second candidate beam set from the plurality of candidate beam sets before the selection of the first candidate beam set; and
determine, based on monitoring the second candidate beam set, not to select a second DL candidate RS from second DL candidate RSs associated with the second candidate beam set,
wherein the first candidate beam set is selected in response to determining not to select the second DL candidate RS.
14. The wireless device of claim 13 , wherein the monitoring priority configuration indicates that a priority of the second candidate beam set is higher than a priority of the first candidate beam set.
15. The wireless device of claim 11 , wherein the first DL candidate RSs comprise:
one or more synchronization signal physical broadcast channel blocks; or
one or more channel state information reference signals (CSI-RSs).
16. The wireless device of claim 11 , wherein the instructions further cause the wireless device to detect that channel qualities of DL RSs in the serving beam set are less than a second threshold.
17. The wireless device of claim 11 , wherein each candidate beam set of the plurality of candidate beam sets is associated with the plurality of DL candidate RSs.
18. The wireless device of claim 11 , wherein:
the preamble is identified by a preamble resource associated with the first DL candidate RS; and
the preamble resource comprises at least one of:
a preamble index,
a transmission resource in frequency domain for the preamble, or
a transmission resource in a time domain for the preamble.
19. The wireless device of claim 11 , wherein the first candidate beam set is selected further based on channel qualities of the candidate beam sets.
20. A system comprising:
a base station; and
a wireless device comprising:
one or more processors; and
memory storing instructions that, when executed by the one or more processors, cause the wireless device to:
report a capability of the wireless device for multiple candidate beam set monitoring;
receive a radio resource control (RRC) message comprising:
a serving beam set;
a plurality of candidate beam sets, wherein:
each candidate beam set, of the plurality of candidate beam sets, comprises a plurality of candidate beams; and
each of the plurality of candidate beams is associated with a corresponding one of a plurality of downlink (DL) candidate reference signals (RSs); and
a monitoring priority configuration of the plurality of candidate beam sets;
detect a beam failure of the serving beam set;
select, in response to the detecting, a first candidate beam set from the plurality of candidate beam sets based on the monitoring priority configuration of the plurality of candidate beam sets, wherein the monitoring priority configuration indicates a monitoring priority order;
select a first DL candidate RS from first DL candidate RSs associated with the selected first candidate beam set based on a channel quality of the first DL candidate RS being greater than a threshold; and
transmit a preamble associated with the first DL candidate RS for beam failure recovery.