Performance Comparison of Direction-of-Arrival Estimation Algorithms for Towed Array Sonar System

Under water acoustic signatures can vary significantly under different environmental conditions. Finding direction-of-arrival (DOA) using towed array in under water environment requires algorithm robustness against variable acoustic signatures. The algorithm should be capable of performing source separation and localization extremely well in complex environments. Concurrently, the algorithm should not be much complex because it will be used in real time and systems needs to identify a target instantly. Array size is another important issue in target positioning because fewer sensors could lead to small size and require less computational cost. In this paper, we present a comparison of the conventional direction-of-arrival algorithm with 2DFFT, MVDR and MUSIC algorithms for the purpose of finding DOA in underwater acoustics. The comparison would be focused on array size, source separation/resolution, signals type and complexity. We showed the DOA results of different algorithms on a simulated signal with giver SNRs (Signal to Noise Ratio) and discuss issues such as resolution, computational complexity, and array size.