Patent ID: 7348926

Claim:
A method of operating a cellular phone covering a plurality of frequency bands, said cellular phone being comprised of a first body, and a second body mechanically connected to said first body through a hinge such that said second body is rotatable at an end thereof relative to said first body, said method including the steps of: (a) detecting whether said first and second bodies are open or closed to each other; and (b) varying a ground length in accordance with the result of said step (a), said ground length being defined as a length of a ground area for an antenna-matching circuit of said cellular phone, wherein said cellular phone includes a first printed substrate arranged in said first body, a first switch formed on said first printed substrate, a second printed substrate arranged in said second body, and a second switch formed on said second printed substrate, said method further comprising the step of grounding said first and second switches when said cellular phone makes communication in a first frequency band, and causing said first and second switches to make an impedance circuit when said cellular phone makes communication in a second frequency band greater than said first frequency band.