Correlation characteristics of signals reflected by the wavy surface of ocean in mirror direction
Abstract
An experimental study was carried out to determine the correlation characteristics of pseudonoise signals reflected from a wavecovered surface in the mirror direction. The major measured quantity was the reciprocal correlation coefficient between the transmitted signal and the reflected signal. The transmitter was lowered from a ship on a 150 m cable. The receiver and preamplifier were lowered to the same depth from a buoy which was allowed to drift from the ship to a distance of 100500 m, the changing distance changing the angle of the beam reflected from the surface of the ocean back down to the hydrophone. The radiator transmitted a pulsed signal with a pseudonoise carrier. The results were interpreted within the framework of ordinary correlation theory by processing several recordings, calculating the sign and ordinary correlation coefficients to determine the variation in sign correlation coefficient as a function of the ordinary correlation coefficient. Graphs of the average variation are presented. It was found that the medium did not distort the signal as it propagated through the water mass (within the limits of experimental accuracy). The correlation coefficient between the transmitted and reflected signals is thus determined entirely by the characteristics of reradiation of the sound by the wavecovered surface.
 Publication:

USSR Report Earth Sciences JPRS UES
 Pub Date:
 June 1985
 Bibcode:
 1985RpESc.......18Z
 Keywords:

 Correlation Coefficients;
 Ocean Surface;
 Underwater Acoustics;
 Variations;
 Wave Reflection;
 Hydrophones;
 Signal Detectors;
 Signal Distortion;
 Signal Transmission