Research Article
Lubis MZ* and Pujiyati S
Abstract
Hydroacoustic method has been used in various field of marine research. Use hydroacoustic method is a method developed to obtain information about the mangrove crab (Scylla sp.). This study analyses the value Target Strength (TS), Power Spectral Density (PSD), and Fast Fourier Transform (FFT) used the instrument hidroakustik. Data collection was performed at the Laboratory of Marine Acoustics using instruments CruzPro PCFF-80 operated with a frequency of 200 kHz. Results of detection of the target by looking at the value of Target strength, strongest TS value can be seen at a depth of 0.6 meters from the transducer with estimations it is the result of target detection. The target strength (TS) of the mangrove crab (Scylla sp.) ranged between –50 and –54 dB. TS value at ping number of 0-500 have a greater value is the value of -55 dB, TS value at that time have in common with TS value at ping number 2500-3000. SV value is no different than the value of TS is caused using 1 target. Echo level (EL) value versus time has highest peak in the range of 115 dB with the lapse ping number is 15-25, with values that are at the end of the echo of ping number of 70 with value is 132 dB rated Power Spectral Density (PSD) is actually located at 2900 s, and depth of a pool is not affect the value of backscatter targets.