| 摘要 |
<p>A digital demodulator includes a reproducing head (1) for reproducing an analog video signal from a recording medium, an analog to digital converter (3) for converting the analog video signal applied from the reproducing head (1) into a digital signal, a Hilbert transform circuit (4) for transforming the digital signal into signals whose phases are shifted by first and second angles from the digital signal, respectively, a frequency detector (9) for detecting a frequency of the transformed signals, a first coefficient circuit (10) for weighting an output signal of the frequency detector (9), a second coefficient circuit (7) for weighting the transformed signals, a multiplier (11) for multiplying output signals of the first and second coefficient circuits (7, 10) together, an equalizer (5) for correcting a frequency characteristic of the transformed signals, and a demodulator (8) for demodulating an output signal of the equalizer (5), wherein the frequency characteristic of the equalizer (5) is corrected in accordance with an output of the multiplier (11). <IMAGE></p> |
