Method and apparatus for using a radio access technology in a mobile station employing a removable memory device

摘要

A mobile station (MS) is provided that includes one or more memory devices that maintain a RAT preference rule and that include a removable memory device (RMD) that maintains a data file that includes a prioritized listing of one or more PLMN/RAT combinations. The MS detects a RAT and a PLMN broadcasting on that RAT and determines a type of the RMD. When the RMD is a type that would maintain information on the detected RAT, the MS determines a priority of the detected PLMN/RAT combination relative to other PLMN/RAT combinations based solely on the prioritizations included in the data file. When the RMD is a type that would not maintain information on the detected RAT, the MS determines a priority of the detected PLMN and RAT relative to other PLMN/RAT combinations based on the RAT preference rule in conjunction with the listing of PLMN/RAT combinations in the data file.

主权项

1. A method, in a mobile station, for selecting a public land mobile network (PLMN) and radio access technology (RAT), the method comprising:
maintaining, in a removable memory device, a data file comprising a prioritized listing of one or more public land mobile networks (PLMNs) in combination with one or more radio access technologies (RATs); wirelessly detecting a RAT and a PLMN broadcasting on that RAT to produce a detected PLMN and RAT combination; determining a type of the removable memory device; in response to determining that the removable memory device is a type that would maintain information on the detected RAT, determining a priority of the detected PLMN and RAT combination relative to one or more other PLMN and RAT combinations based solely on the prioritizations included in the data file in the removable memory device; in response to determining that the removable memory device is a type that would not maintain information on the detected RAT, determining a priority of the detected PLMN and RAT relative to one or more other PLMN and RAT combinations based on a RAT preference rule separate from, and in conjunction with, the listing of PLMN and RAT combinations in the data file in the removable memory device; and selecting a PLMN and RAT for radio communications based on the determined priority of all the found PLMNs and RATs.