| 摘要 |
PURPOSE:To implement interference compensation over a wide frequency range with respect to the revision in the frequency of an object interference wave by selecting an intermediate frequency band for the operating frequency band of a voltage controlled oscillator so as to widen the frequency variable range. CONSTITUTION:A PLL circuit comprising a voltage controlled oscillator 7, a low pass filter 8, a phase comparator 9, a phase shifter 10 and an orthogonal detector 1' is phase-locked to an output of an analog adder 11 being an extracted interference signal (f). Moreover, signals i,q being extracted interference wave signals whose jitter component is suppressed are outputted. The signals i,q are respectively converted into, e.g. 3-bit data signals d(D'1-D'3) by A/D converters 14,15 and outputted from an interference wave detection circuit 6. Since the frequency band of the oscillator 7 is selected to be an intermediate frequency band, the variable range of the frequency is widened. |
