METHOD AND APPARATUS FOR AN OPTIMIZED SEARCH FOR SERVICE WHEN A MULTI-MODE UE GOES OUT OF SERVICE

摘要

The present disclosure presents a method and an apparatus for searching for service when a multi-mode UE goes out of service (OOS). For example, the disclosure presents a method for receiving a request to scan frequencies of a RPLMN of a first RAT and scanning the frequencies of the first RAT based on an acquisition database (ACQ DB). In addition, such an example method, may include sending an available PLMN list to the NAS layer, switching to a second RAT based on a request from the NAS layer, scanning frequencies of the second RAT based on the ACQ DB, and camping on a frequency of the second RAT found during the scanning of the frequencies of the second RAT based on the ACQ DB. As such, a method and an apparatus for searching for service when a multi-mode UE goes OOS may be achieved.

主权项

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.