| 摘要 |
PURPOSE:To use a digital phase detector operated at 1/2 of a symbol speed so that a clock can be reproduced even against a demodulating signal of a high speed, in the clock reproducing device for which a phase-locked loop is used for controlling optimumly a phase of a reproducing clock from a zero crossing point of a demodulating signal. CONSTITUTION:A phase-locked loop is constituted of a phase detector 7 operated by a clock of 1/2 of a symbol speed, a loop filter 2, a D/A converter 3, a VCO 4, a first frequency divider 6, and a second frequency divider 5. An output of a first frequency divider 5 becomes a reproducing clock controlled optimumly by phase different data from the phase detector 7. |
