| 摘要 |
<p>PURPOSE:To increase target detecting efficiency, by inputting a signal which has received and detected an echo of a transmission pulse, and a signal which has smoothed said signal by a low-pass filter, to a differential amplifier, and detecting a difference of both the signals. CONSTITUTION:A sonar video signal 14 is detected by a detector 11, and a waveform 15 is obtained. This signal 14 is inputted as a waveform 16 to one terminal of a differential amplifier 13 through a low-pass filter 12, and also a detection signal 15 is inputted to the other terminal. An output of the differential amplifier 13 becomes as a waveform 17. In this way, a mean value of an output by a background noise, a reverberation, etc. becomes small, an echo signal from a target is discriminated easily, and fatigue of a measure is reduced, by which the detecting efficiency is greatly elevated.</p> |
