Shallow water High Resolution Bathymetric Side Scan Sonar

With about 2 years' work, the Instituted of Acoustic, Chinese Academy of Sciences (IACAS) and the Teledyne RD Technology (Shanghai) Inc. (RDT) have developed the Shallow water High Resolution Bathymetric Side Scan Sonar (SBSSS). It is mainly composed of sonar deck control unit, sonar housing (include electronic unit and watertight pod) and two sonar arrays. The SBSSS can obtain the incidence angle of the backscatter from the water bottom on sonar array, directly. Using this system, the grazing angle, distance and signal intensity (acoustic intensity) of the target on the water bottom or in the water can be measured. Working with motion sensor, CTD sensor and GPS (or RTK) system, the SBSSS can get the high resolution terrain and geomorphy of the water bottom, synchronously. After post-processing, the contour map and side scanning map, which is better than the normal side scanning map, can be obtained. The SBSSS also can be used to detect the target on the water bottom or in the water. The technique of sea bottom automatic detect and estimation direction of arrival (DOA) based on multi-subarray subspace fitting (SBAD-EDMSF) is researched and progressed. It can improve the accuracy of depth measurement. Some other theory about the SBSSS, such as estimation technique about the number of signal sources, signal copy technique, attitude correct technique, real time signal processing technique and etc., is studied. Using these methods, the sonar can get better result in the complex acoustic field in the shallow water.