| 摘要 |
PURPOSE:To eliminate the influence of mixture of a PCM transmission signal into a clock receiving signal near a threshold level, by delaying the phase of the clock signal from a receiving part after multiplying this clock signal in a transmitting part by 2. CONSTITUTION:When a clock signal (a) is transmitted from receiving part 1, this signal is multiplied in a multiplying circuit 25 by 2 into a waveform (b) and is received as a waveform (c). The waveform (c) is subjected to full-wave rectification to a waveform (d) and is shaped to a waveform (e) by a waveform shaping circuit 22 and has the phase delayed to a waveform (f) by a phase delay circuit 24. PCM data is added to this signal (f), and they are transmitted as a signal (g) from a transmitting circuit 23. Consequently, a noise N due to the PCM transmission signal is generated at a point where the clock receiving signal is inverted to a waveform (h), and the allowable value of this noise is very large. Further, intervals of occurrence of the noise are extended considerably, and therefore, a decision point is selected in a wide range. |
