Acoustic backscattering at low grazing angles from the ocean bottom. Part II. Statistical characteristics of bottom backscatter at a shallow water site

Analyses of the statistical characteristics of bottom backscatter, measured in shallow water off San Diego, California, are presented. (The initial results of the experiment were presented by T. G. Goldsberry, S. P. Pitt, and R. A. Lamb at the 104th Meeting of the Acoustical Society of America, Orlando, FL, 8–12 November 1983.) The experimental sonar, mounted on the sea bottom, was operated at 30 kHz to gather data over a wide sector of the bottom. The bottom was patches of coarse and fine sand. The distribution function and probability of false alarm function of the detected envelope of widebeam and narrowbeam signals were measured. Some spatial and temporal correlation functions of the signal amplitudes were measured. A limited attempt was made to compare the results with existing theoretical models.