| 摘要 |
PURPOSE:To attain signal converting operation so tht a demodulation signal at the transmission side is a desired signal by multiplying a reception spread spectrum signal and a signal retarding the said reception spread spectrum signal at the reception side and extracting a low frequency component of the multiplied signal so as to obtain a demodulation signal and outputting it. CONSTITUTION:The reception spread spectrum signal from a signal line 158 is inputted to a delay circuit 106, where the signal is subject to delay for one period's share of a pseudo random series and outputted to a signal line 159. Further, the reception spread spectrum signal on the signal line 158 and the signal subject to delay on the signal line 159 are multi plied by a multiplier 107 and the result is outputted to a signal line 160. The low frequency component of the signal on the signal line 160 is extracted by a low pass filter 108 and outputted to a signal line 161 as the demodulation data. Then the reception spread spectrum signal on the signal line 158 is a signal waveform shown in figure (c). Then the signal is subject to delay for one period's share of the pseudo random series at a delay circuit 106, the signal on the signal line 159 is as shown in figure (d). Since the signals in figures c, d are multiplied by a multiplier 107, the signal on the signal line 160 is as shown in figure (e) and its waveform is equal to that of the original binary data shown in the figure (a). |
