US 11,943,800 B2
User equipment that determines radio link failure using timer and radio link quality, and corresponding base station
Naoki Kusashima, Kanagawa (JP)
Assigned to Sony Group Corporation, Tokyo (JP)
Filed by Sony Group Corporation, Tokyo (JP)
Filed on Feb. 2, 2023, as Appl. No. 18/163,285.
Application 18/163,285 is a continuation of application No. 17/373,797, filed on Jul. 13, 2021, granted, now 11,582,767.
Application 17/373,797 is a continuation of application No. 16/322,125, granted, now 11,082,988, issued on Aug. 3, 2021, previously published as PCT/JP2017/023624, filed on Jun. 27, 2017.
Claims priority of application No. 2016-156464 (JP), filed on Aug. 9, 2016.
Prior Publication US 2023/0189322 A1, Jun. 15, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. H04W 72/00 (2023.01); H04J 11/00 (2006.01); H04L 5/00 (2006.01); H04L 25/02 (2006.01); H04L 27/00 (2006.01); H04W 16/14 (2009.01); H04W 56/00 (2009.01); H04W 72/04 (2023.01); H04W 72/54 (2023.01); H04W 72/542 (2023.01); H04W 76/28 (2018.01)
CPC H04W 72/542 (2023.01) [H04J 11/0079 (2013.01); H04L 5/0048 (2013.01); H04L 25/0202 (2013.01); H04L 27/0006 (2013.01); H04W 16/14 (2013.01); H04W 56/001 (2013.01); H04W 72/04 (2013.01); H04W 72/54 (2023.01); H04W 76/28 (2018.02)] 9 Claims
OG exemplary drawing
 
1. A user equipment comprising:
a radio transceiver configured to perform wireless communication in a first cell served by a first base station and a second cell served by a second base station; and
circuitry configured to:
perform Radio Link Monitoring (RLM) using downlink physical signals transmitted on the first cell served by the first base station, wherein the downlink physical signals include Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), and a downlink Demodulation Reference Signal (DMRS),
measure a radio link quality using the downlink physical signals,
evaluate the radio link quality against thresholds Qout and Qin,
on condition that the radio link quality is worse than the threshold Qout, indicate out-of-sync to higher layers from a physical layer,
on condition that the radio link quality is better than the threshold Qin, indicate in-sync to the higher layers from the physical layer,
start a first timer when the out-of-sync is consecutively indicated to the higher layers from the physical layer, and
determine that a radio link failure occurs in the first cell served by the first base station in a case where the first timer expires without consecutive in-sync indications, wherein
the first timer used to determine whether the radio link failure occurs in the first cell served by the first base station is different from a second timer used to determine whether a radio link failure occurs in the second cell served by the second base station.