Patent ID: 8670761

Claim:
A method of efficiently identifying carrier frequencies in a wireless communication system by a mobile User Equipment (UE) upon crossing a country border, comprising: storing a Mobile Country Code (MCC) received over the air interface of a Public Land Mobile Network (PLMN) of a wireless communication service provider currently being accessed by the UE in a first country; obtaining an updated MCC; comparing the updated MCC to the stored MCC; and in response to the updated MCC being different than the stored MCC, determining that the UE has crossed a political border into a second country, initiating a timing function operative to indicate the elapse of a predetermined duration, if the UE supports more than one Radio Access Technology (RAT), sending a notification of the changed MCC to each supported RAT, performing a search, in each supported RAT, of all frequencies on which the UE can obtain wireless communication services, discovering wireless communication services available to the UE in the second country as a result of the frequency search, and repeating the method steps only after expiration of the predetermined duration.