| 摘要 |
PURPOSE:To obtain a distortionless amplitude demodulation output, by leading out a prescribed function output based on a phase democulation output, and correcting a distortion of the amplitude demodulation output in accordance with said function output, in a receiver for receiving an amplitude phase modulation broadcasting wave. CONSTITUTION:To a phase detecting circuit 1 and an amplitude detecting circuit 5, a signa output is provided from the intermediate frequency amplifying part. The output whose phase has been demodulated by the circuit 1 is provided to a phase distortion correcting circuit 2, in which its phase distortion component is removed, and said output is provided to a differentiating circuit 3. The signal differentiated by the circuit 3 is applied to a function generating circuit 4. The circuit 4 outputs a reciprocal of an amplitude characteristic of a transfer function in a signal transfer path extending from an antenna of a receiver to the circuit 5 with respect to the instantaneous frequency of a receiving signal, in accordance with a differential output from the circuit 3, and inputs it to a multiplying circuit 6. To the circuit 6, a signal whose amplitude has been demodulated is applied, is multiplied by a function output from the circuit 4, an amplitude characteristic term is erased, a direct current component is removed by a capacitor 7, and a distortionless amplitude demodulation output is outputted. |
