Patent ID: 7392030

Claim:
An antenna switching method for a cell phone having built-in antennas including first and second antennas, comprising: temporarily selecting one of the first and second antennas at the start of a standby state for waiting for one of an outgoing call and incoming call for speech communication and packet communication, and measuring reception levels of the first and second antennas; switching the antennas when the reception level of one of the first and second antennas which has been temporarily selected is lower than the reception level of the other of the first and second antennas; executing a cell search when a power switch of the cell phone is turned on; selecting one of the first and second antennas which was selected when the power switch was turned off; determining whether the execution of the cell search has succeeded; and switching the antenna to the temporarily selected antenna when the cell search has failed, and executing the cell search; when the cell search has succeeded, shifting to a position registration sequence for a base station to perform position registration of the cell phone; determining whether the position registration has succeeded; when the position registration has failed, selecting an antenna which has not been selected for the cell search, and returning to the step of performing position registration; and when the position registration has succeeded, shifting to a standby state.