The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 11, 2006
Filed:
Sep. 30, 2002
Scott G. Hicks, Apex, NC (US);
Sam Mullis, Apex, NC (US);
Bassam Jarrad, Apex, NC (US);
Abstract
A system and method for determining if a mobile phone is in a home area that does not rely exclusively on the HPLMN data programmed into the mobile phone. To determine whether the mobile phone is in a home area or in a roaming area a processor in the mobile phone checks the PLMN control information in an over-the-air received signal. If the PLMN data matches the PLMN data stored in the mobile phone SIM card IMSI file, then the current network is a home network. Otherwise, the received LAI control data is checked to see whether it matches any LAI data in the OPL file of the SIM card in the mobile phone. If the received LAI data does not match any LAI data in the OPL file, then the network is not a home network but a roamed into network. If the received LAI data does match LAI data in the OPL file, then the OPL file is further examined to see whether the PNN record that the OPL record points to is the first record in the PNN file. If it is, then the network is a home network. If it is not, then the network is a roamed into network.