Patent ID: 6466774
Filing Date: 2002-10-15
Classification: H01Q

Abstract:
A wireless handset used in a communication system that switches a plurality of call frequencies for use, comprising: a tunable antenna having a circuit for center frequency of impedance matching; a strength detector for retaining received signal strength for each call frequency; a circuit that refers to a frequency to voltage conversion table retaining a relationship between a digital signal for controlling a DC voltage value for setting a center frequency of impedance matching of said tunable antenna and each call frequency, to output a digital signal corresponding to information about a call frequency indicating an input maximum received signal strength; and a digital to analog converter for generating a DC voltage for setting a center frequency of impedance matching of the tunable antenna in accordance with said digital signal, wherein control is performed by said DC voltage so that a center frequency of impedance matching of the tunable antenna tunes to a call frequency.