Patent ID: 6340941
Filing Date: 2002-01-22
Classification: H03K,H04L

Abstract:
A digital-signal forming circuit comprising:an intermediate frequency demodulator to output a demodulated intermediate frequency signal by demodulating an intermediate frequency received signal; a signal comparator to shape the demodulated signal into rectangular waves by performing a voltage comparison between the demodulated signal and a reference voltage and to output the rectangular waves as a digital signal; an average-reference-voltage circuit to output an average reference voltage by averaging the demodulated signal; a fixed-reference-voltage circuit to output a fixed reference voltage having a predetermined voltage; a selection switch to select either of the two reference voltages and output the selected voltage to said signal comparator; a make-and-break switch to one of enable and disable a connection between said demodulator and said average-reference-voltage circuit; a radio-requency-received-signal-strength detector to output a strength signal in accordance with the strength of a radio-frequency received signal; and a controller to control the selecting operation of said selection switch in accordance with the magnitude of the strength signal.