| 摘要 |
PURPOSE:To detect a false error with high precision without the influence due to the waveform distortion of a clock signal supplied from a receiver by shaping the waveform of the clock signal inputted to a flase error detector. CONSTITUTION:A base band signal before demodulation of a receiver 2 is supplied to the first sampler 9a and the second sampler 9b from an input terminal 6. A reproduced clock signal given to an input terminal 7 has higher harmonic component eliminated by a tank circuit 12 and becomes a sine wave signal. In this stage, the waveform distortion of the reproduced clock signal is eliminated completely. The second phase shifter 10b shifts slightly the phase of the clock signal supplied to the first sampler 9a, and the second sampler 9b samples the base band signal at a time elapsed by DELTAT from the Nyquist point. The output of the second sampler 9b is the reproduced data having the degraded quality in the sense of increase of a bit error rate, and the error rate of this output signal is called a false error rate, and the false error pulse is outputted to an output terminal 8. |
