Polyphase FIR filters for the demodulation of chrominance signals

The author presents a scheme and its polyphase FIR (finite-impulse-response) filter implementation for the demodulation of chrominance signal into in-phase and quadrature-phase components. The scheme applies to any system whose sampling frequency is related to the color subcarrier frequency by a rational factor. The authors presents the criteria for choosing a sampling frequency for the digitization of a TV studio signal and addresses the issue of digital demodulation of the chrominance component in a composite video signal