Patent ID: 7239357

Claim:
A digital IF demodulator, including: an analog-to-digital (A/D) converter configured to receive an analog IF signal and generate a digital IF signal; a video recovery circuit, including a first digital complex mixer coupled to an output of said A/D converter, said first digital complex mixer configured to down-convert said digital IF signal to a baseband signal, said first digital complex mixer having a local oscillator that is tuned to down-convert a picture carrier in said digital IF signal to DC; and a Nyquist filter that receives said baseband signal from said first digital complex mixer and is configured to perform Nyquist shaping on said baseband signal, a digital video output derived from an output of said Nyquist filter; an audio recovery circuit, including a second digital complex mixer coupled to an output of said first digital complex mixer, said second digital complex mixer configured to down-convert an audio component in said baseband signal to an audio baseband signal; and a FM demodulator that demodulates said audio baseband signal to generate a digital audio output.