US 12,446,112 B2
Method for improved emergency call
Guojing Liu, Beijing (CN); Dongsheng Wang, Beijing (CN); Chaofeng Hui, Beijing (CN); Fojian Zhang, Shenzhen (CN); Haibo Liu, Shanghai (CN); Xiaomeng Lu, Shanghai (CN); and Xuesong Chen, Beijing (CN)
Assigned to QUALCOMM Incorporated, San Diego, CA (US)
Appl. No. 17/999,099
Filed by QUALCOMM Incorporated, San Diego, CA (US)
PCT Filed Jun. 30, 2020, PCT No. PCT/CN2020/099323
§ 371(c)(1), (2) Date Nov. 17, 2022,
PCT Pub. No. WO2022/000276, PCT Pub. Date Jan. 6, 2022.
Prior Publication US 2023/0217545 A1, Jul. 6, 2023
Int. Cl. H04W 76/50 (2018.01); H04W 76/18 (2018.01)
CPC H04W 76/50 (2018.02) [H04W 76/18 (2018.02)] 20 Claims
OG exemplary drawing
 
1. A method for wireless communications by a user equipment (UE), comprising:
camping on:
an anchor cell of a first radio access network (RAN) via a first subscriber identity module (SIM) that is serving as a default data subscriber (DDS); and
another cell of the first RAN via a second SIM that is serving as a non-DDS;
obtaining a trigger for the UE to perform a circuit switched (CS) emergency call via the first SIM;
attempting the CS emergency call via the first SIM and a second RAN;
detecting a failure to perform the CS emergency call via the first SIM and the second RAN; and
in response to the detection, re-attempting the CS emergency call via the second SIM and the second RAN, without disabling RAN capabilities associated with the first SIM; and
after completion of the CS emergency call, returning to the first RAN based on the re-attempting the CS emergency call via the second SIM and the second RAN without the disabling the RAN capabilities associated with the first SIM.