Patent ID: 6771960
Filing Date: 2004-08-03
Classification: H04W

Abstract:
A method for a radiotelephone to scan for service in a radiotelephone system during an idle mode, the radiotelephone system having a plurality of carriers for providing radiotelephone service to a radiotelephone within a corresponding geographic area, each carrier providing communication services within a radio coverage area established by fixed site base stations, the method comprising the steps of:powering up, registering and camping the radiotelephone on the radiotelephone system; scanning by the radiotelephone while in idle mode for adjacent carriers having the strongest signal strength; establishing by the radiotelephone while in idle mode a list of a predetermined number of carriers having the strongest signal strengths from cells proximate to the cell where the radiotelephone is camped, and reading the BCCH and BSIC data transmitted by each carrier; determining by the radiotelephone those proximate carriers from the list that will allow camping by the radiotelephone by determining in the radiotelephone if the carrier provides service from known reselection criteria stored for that BSIC before the radiotelephone has moved into a proximate cell; scanning for other carriers that will allow camping within the area to substitute for those carriers found in the determining step that will not allow camping by the radiotelephone before the radiotelephone has moved into a proximate cell; modifying the list to include those carriers that will allow camping by the radiotelephone found in the scanning step before the radiotelephone has moved into a proximate cell; and camping upon one of the carriers that will allow camping by the radiotelephone from the list when the radiotelephone leaves the cell where it is presently camped.