The Reflection of Low Frequency Sonar Signals from a Smooth Ocean Bottom. Part I. Experimental Reflection Losses at Locations off the California Coast and in the Bering Sea

摘要

Underwater acoustic tests in three different areas are discussed: Area I is in 200-fathom water while Areas II and III are deep-water, 2000-fathom areas. From the data obtained bottom reflection losses were computed as a function of grazing angle for low frequency, 0.7 to 3.0 kc sound pulses. Measurements in Area I utilized short pulses and acoustic-path geometries that would resolve the bottom reflected paths; the analysis was then accomplished by comparing the direct signal with the signal which suffers one bottom reflection. The experiments in the deep-water areas did not attempt acoustic path resolution and the bottom loss was derived from the difference between the measured propagation loss and the theoretical propagation loss for that range and for total reflection at the grazing angle.