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Underwater Weak Target Detection Algorithm Based on Space-time Distribution Processing

Based on the space-time distribution map obtained from long-term observation of fixed sonar, multi-frame data correlation is realized according to the time and space continuity of the target. Use a linear function fitting algorithm to predict the target angle of a missing frame which can prevent the track truncation caused by miss of target. Then the minimum continuous correlation points and the maximum allowable loss points in the algorithm are set through probability calculation to reduce the false alarm probability. Simulation results show that the algorithm can achieve weak target detection.