| 摘要 |
<p>PURPOSE:To make possible the automatic detection of disturbance signals, disturbance arrival bearing and run length by automatically generating the threshold in a specified azimuth region on the basis of the maximal value in average amplitude value of one scan part and its azimuth angle. CONSTITUTION:A maximal value extractor 6 eliminates smaller average amplitude value than detection limit threshold 104 from input average amplitude values to compare with its relative size in order of azimuth direction on the residue to extract the largest of the most average amplitude values as the maximal value so as to transmit into a threshold generator 7 as maximal value data 101 along with its azimuth angle. In the generator 7, a threshold-set constant 10 is multiplied by the maximal value to show as lower value than it so as to output the value in which a specified azimuth range part that threshold azimuth width 106 designates is maintained as a detection threshold value 108. A disturbance detector 8 compares the average amplitude value 103 of next scan determining the threshold 108 with the threshold 108, a disturbance detection hit 109 is output whenever it exceeds the threshold 108 and a disturbance data extractor 9 extracts run length along with central azimuth to match with a disturbance level so as to output a disturbance signal message 110.</p> |
