US 12,082,011 B2
Configuring radio link monitoring (RLM) for moving radio access network (RAN)
Helka-Liina Määttänen, Helsinki (FI); Talha Khan, Santa Clara, CA (US); Xingqin Lin, Santa Clara, CA (US); Henrik Rydén, Solna (SE); Sebastian Euler, Storvreta (SE); and Olof Liberg, Enskede (SE)
Assigned to Telefonaktiebolaget LM Ericsson (Pub, Stockholm (SE)
Appl. No. 17/285,252
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Nov. 1, 2019, PCT No. PCT/IB2019/059395
§ 371(c)(1), (2) Date Apr. 14, 2021,
PCT Pub. No. WO2020/089848, PCT Pub. Date May 7, 2020.
Claims priority of provisional application 62/754,108, filed on Nov. 1, 2018.
Prior Publication US 2021/0385675 A1, Dec. 9, 2021
Int. Cl. H04W 24/08 (2009.01); H04B 7/08 (2006.01); H04W 76/19 (2018.01); H04W 76/28 (2018.01); H04W 84/06 (2009.01)
CPC H04W 24/08 (2013.01) [H04B 7/088 (2013.01); H04W 76/19 (2018.02); H04W 76/28 (2018.02); H04W 84/06 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method, performed by a user equipment (UE), for radio link monitoring (RLM) in a combined terrestrial and satellite wireless communication network, the method comprising:
during a discontinuity in a connection between the UE and a terrestrial network node (TNN), performing RLM of the connection based on a second configuration, wherein:
the connection includes a first link between the UE and a satellite and a second link between the satellite and the TNN, and
the discontinuity comprises a link switch in at least one of the first link and the second link; and
performing RLM of the connection based on a first configuration, during at least one of the following: before the discontinuity, and after the discontinuity,
performing RLM of the connection before the discontinuity based on the first configuration including at least one of the following first operations:
 monitoring a physical downlink control channel (PDCCH) transmitted by the satellite;
 measuring of one or more reference signals (RS) transmitted by the satellite;
 determining an average of a plurality of the measurements of the RS;
 detecting in-sync (IS) and out-of-sync (OOS) conditions based on a plurality of the measurements or a plurality of the averages of the measurements;
 counting consecutive detections of IS conditions;
 counting consecutive detections of OOS conditions;
 initiating a radio link failure (RLF) timer after a predetermined number of consecutive OOS conditions;
 detecting a beam failure based on a plurality of the RS measurements or a plurality of the averages of the RS measurements; and
 initiating a link recovery procedure after expiration of the RLF timer or after detecting a beam failure; and
performing RLM of the connection after the discontinuity based on the first configuration comprising monitoring the PDCCH transmitted by the satellite, being based on one of the following:
 a link recovery search space received from the TNN after the discontinuity; or
 if no link recovery search space is received after the discontinuity, a link recovery search space configured before the discontinuity.