| 摘要 |
PURPOSE: To demodulate stably data even when the received electric field strength is fluctuated resulting in changes in the amplitude of a delay detection signal waveform. CONSTITUTION: A correlation device 2 applies inverse spread to a spread spectrum modulation signal to output a correlation signal, a delay detection means comprising a delay line 3 and a multiplier 4 applies delay detection to a signal from the correlation device 2, and the receiver is provided with a threshold level generating section 6 consisting of an absolute value circuit 7 that takes an absolute value of the delayed detection signal outputted through a low pass filter 5, of a peak hold circuit 8 detecting a peak of the signal from the absolute value circuit 7 and providing an output, and of an arithmetic circuit 9 calculating a prescribed level of the signal from the peak hold circuit 8 and providing an output of a signal, and a data demodulation section 10 receives a signal from the threshold level generating section 6 as a threshold level to discriminate the delay detection signal and to demodulate the data thereby providing an output of the result. |
