Importance

Loading Importance Indicators...

Abstract

A remotely programmable cellular mobile radiotelephone (CMR 12) is configured to select (1300) a cellular system (14-16) with which to communicate while roaming. The CMR (12) utilizes a default system selection process. The system selected using this default process is identified (1302) and a SID list (1402) is checked to see if the system identification number (SID) of the identified system is on the list (1402). The SID list (1402) is maintained in a current state through remote programming sessions (1500). When the default system's SID is not on the list (1402), CMR (12) operation continues normally. When the default system's SID is on the SID list (1402), the default system selection process is replaced with an alternate system selection process (1316-1322). If a new system selected by the alternate process is not available or if a new system is available but listed on the SID list (1402), then the CMR (12) simulates a no service mode of operation (1332-1338). Simulation of a no service mode of operation ceases when an actual no service condition occurs (1222). If a new system selected by the alternate selection process is available and not listed on the SID list (1338), then operation on the new system is permitted. After a predetermined duration of operation on the new system, the default selection process is restored and the procedure repeats if necessary.

Loading the Abstract Image...

First Claim