SINGLE SECAM COLOR SIGNAL DEMODULATOR USING TWO REFERENCE FREQUENCIES

摘要

PURPOSE: A single SECAM color signal demodulator is provided to reduce the manufacture cost while preventing the deterioration of the demodulating capability by employing a common demodulator using two carrier signals. CONSTITUTION: A quadrature type demodulator(100) inputs a composite color signal of the SECOM type to provide a demodulated color difference signal with the elimination of noise. A frequency generator(200) inputs a demodulation reference frequency and provides a first reference frequency and a second reference frequency. A filter tuner(300) inputs the first reference frequency, the second reference frequency, and the demodulated color signal to provide a filter tuning signal. A permutator(400) outputs a demodulated color difference signal(B-Y) of blue color series.