| 摘要 |
PURPOSE:To obtain a system where synchronism and phase modulation are obtained easily by using an SAW device having three sets of reed screen transducers at the transmission system and reception system. CONSTITUTION:A bipolar impulse signal as shown in waveform A is used as an input signal in the transmission system. The waveform A is separated into two signals according to the polarity via a polarity separator 11. Then an output signal of a monostable multivibrator 12 is as shown in signal waveforms D, E. The signal waveforms D, E are inputted to the two input transducers of the SAW device 14, delayed via the output transducer and a burst signal as shown in swaveform H subject to phase modulation is outputted. In the reception system, a burst signal of a signal waveform L and an impulse signal for synchronism of a signal waveform N are inputted respectively to the input transducer of the SAW device 21. The two signals are burst signals as shown in signal waveform O by the signal processing of the SAW device 21. The signal waveform O becomes a signal waveform P via a detector 22, a signal corresponding to the polarity of the input signal of the transmission system. Further, the signal is synchronized with the input signal at the transmission system. |
