Circuit arrangement for filtering and demodulating a signal frequency-modulator with at least one audio signal

摘要

A digital television receiver circuit filters and demodulates a signal contained in the input signal of the television receiver and frequency-modulated with at least one audio signal. The only A/D converter required in the circuit is the converter for changing the video signal from analog to digital form. The circuit uses digital filters, a digital mixer, decimation stages and a digital frequency demodulator stage to separate the audio signal from the composite video signal.