Patent ID: 9198088
Filing Date: 2015-11-24
Classification: H04W

Abstract:
1. A method for searching for service when a multi-mode user equipment (UE) goes out of service (OOS), comprising: receiving a request at the UE, from a non-access stratum (NAS) layer, to scan one or more frequencies of a registered public land mobile network (RPLMN) associated with a first radio access technology (RAT), wherein the first RAT is a last camped RAT of the UE; scanning the one or more frequencies of the first RAT based on an acquisition database (ACQ DB); sending an available PLMN list to the NAS layer in response to determining that the RPLMN is not found during the scanning of the first RAT based on the ACQ DB; switching to a second RAT based on a request from the NAS layer in response to identifying that a Home PLMN (HPLMN) is not in the available PLMN list; scanning one or more frequencies of the second RAT based on the acquisition database (ACQ DB); and camping on a frequency of the second RAT found during the scanning of the one or more frequencies of the second RAT based on the ACQ DB.