Patent ID: 6681118
Filing Date: 2004-01-20
Classification: H04W

Abstract:
A method of controlling a dual mode mobile telephone that automatically selects from among a cellular mode and a cordless telephone mode, wherein the mobile telephone functions as a cellular telephone communicating through a cellular network when operating in the cellular mode, the method comprising;pre-registering with a base station during which the mobile station stores base station identification information, wherein the base station is coupled among the cellular network and a public switched telephone network (PSTN), wherein the base station includes operational information received from the cellular network including base station operating frequencies and base station operating power levels that support user-selected service levels, and; while in the cellular mode, recognizes locations that are in proximity to the base station in accordance with the base station operating power levels; searching for the base station using the stored base station identification information and, upon detecting the base station, automatically de-registers from the cellular network, couples to the base station, registers with the base station, automatically switches to the cordless telephone mode, and confirms the switch to the cordless telephone mode with the base station, wherein the base station provides a call forwarding update message to the cellular network requesting routing of calls addressed to the mobile telephone to the base station via the PSTN; receiving a call information message from the base station when the base station receives a forwarded call from the cellular network directed to the mobile telephone, wherein the call information message is selected by the base station in response to a determination of mobile telephone status; and receiving the forwarded call via the PSTN and the base station.