LONG BASELINE PRECISION NAVIGATION SYSTEM FOR SYNTHETIC APERTURE SONAR

A two transponder long baseline positioning system to measure the sway of a free towed Synthetic Aperture Sonar (SAS) is proposed. A Matlab simulation predicts a worst case sway accuracy of ±1.5 cm over a 150m long tow path with an update rate of 14Hz. The sway is measured with respect to freely deployed transponders which remain stationary on the seabed connected via cables to floating buoys housing GPS timing receivers. Sway information is completely independent for each sonar ping and allows the deblurring of the SAS images by post processing.

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