| 摘要 |
PURPOSE:To prevent malfunction from occurring by performing transmission with an additional signal removed after generating a parity signal with the additional signal added to a data signal during modulation and by making parity checks with the additional signal added during demodulation. CONSTITUTION:At the rise of pulse signal Sp, additional signal D from additional- signal generating circuit 8 is preset to shift register 7. In a period for following twelve bits, the twelve-bit component of a data signal from PCM converter circuit 2 is supplied to time-axis compressor circuit 4 via selector circuit 3 and also sent to register 7 via exclusive-OR circuit 6. As a result, a parity signal is formed with an additional signal added to the data signal during modulation, and the data signal with this additional signal removed is transmitted; and then parity checks are made with the additional signal added during demodulation. Therefore, even if the entire data signal and parity signal are shifted, it can be made possible to detect an error for the prevention of malfunction. |
