JPS5766371A - Color indication device for underwater detection - Google Patents

Abstract

PURPOSE:To make it possible to generate stable signals, by emitting ultrasonic wave pulses in directions at an angle of alpha to a horizontal surface, arranging received waves in time series in order of direction, compensating drastic variation by before- and-after correlation and making indications on a color CRT. CONSTITUTION:Reflected waves, which are obtained by emitting ultrasonic wave pulses in all directions from a wave-emitting-and-receiving unit 1 at an angle of alpha to a horizontal surface in mechanism of emitting and receiving waves in plural directions, are arranged in time series by a changover terminal. And then, the waves are put into a 'write' circuit 11 through an averaging circuit 8, an A/D converter 9 and a correlating circuit 10. An output of a ''write'' circuit 11 is written into an rtheta memory circuit 12 which an address circuit 13 directs by a direction counter 4 and a distance counter 7. An output of the rtheta memory circuit 12 is re-recorded into an XY memory circuit 16 by the direction of a cordinate converting circuit 17. A part of the output of the rtheta memory circuit 12 is fed back to the correlating circuit 10, and when a difference from a new signal proved to be more than scheduled, it is compensated to control a drastic variation. And thereby, it becomes possible to read the XY recording circuit 16 and indicate a stable signal on a color CRT22.