FM MULTIPLEX SIGNAL DEMODULATION CIRCUIT BLOCK FOR FM MULTIPLEX BROADCAST RECEIVER

摘要

PROBLEM TO BE SOLVED: To provide the FM multiplex signal demodulation circuit block for FM multiplex broadcast receiver where demodulation of all FM multiplex broadcast signals is conducted by only digital processing without the use of an expensive A/D converter. SOLUTION: An FM multiplex signal demodulation circuit block 120 is provided with a limiter amplifier 111, and the limiter amplifier 111 receives an FM-IF signal from an FM tuner 102 of an FM radio reception block 106. The limiter amplifier 111 amplifies weak input signals, applies the limiting to the signals in a digital signal level, and outputs binary-processed FM-IF signals. A delay circuit 114 and a multiplier 115 or the like apply the digital signal processing to the signals and outputs FM multiplex broadcast data.