| 摘要 |
PROBLEM TO BE SOLVED: To obtain a simple circuit with high reliability in the communication system suppressing a local amplitude at a phase change point by applying waveform shaping processing to a detected signal, generating one-shot pulse signal and outputting a demodulation signal. SOLUTION: A reception circuit 30 applies electromagnetical conversion to a magnetic signal B to generate a reception signal C. An amplitude suppression point detection circuit 410 generates an check amplitude suppression point detection signal G from the reception signal C. Then a waveform shaping circuit 420 applies waveform shaping processing to the detection signal G to produce a single shot pulse signal J including a pulse with an 8-clock width at two phase change positions. Then a differential code demodulating circuit 430 generates a demodulation signal D from the single shot pulse signal J so as to demodulate a bit pattern of 8-bit delay. Furthermore, the demodulation signal D is sampled by a sampling circuit 50 and given to a processing section 60, where processing corresponding to the content of data is conducted. Thus, a simple circuit with high reliability is realized even for the communication system where local amplitude at phase change points is suppressed. |
