| 摘要 |
<p>PURPOSE:To certainly detect the presence of a moving body in addition to usual data transmission by removing a receiving signal containing a transmission signal component using an attenuator to detect only the receiving signal from the moving body by a peak holding circuit. CONSTITUTION:The output signal (h) of an attenuator 16 is inputted to a detection circuit 23. The output signal (h) inputted to the detection circuit 23 is amplified by a high frequency amplifier 24 and the pulselike waveform thereof is detected by a detector 25. The detected signal is again amplified by an amplifier 26 to be outputted from the detection circuit 23. The output signal (i) of the detection circuit 23 is inputted to a peak holding circuit 35 which in turn detects the peak level of the inputted output signal (i) to hold the same up to the falling time of the next output signal (c) to output said signal (i) as an output signal (j).</p> |
