A fast high-resolution method for bearing estimation in shallow ocean

We propose a concise underwater array model based on normal mode theory and put forward a new bearing estimation method using generalized Rayleigh ratio theory to lighten the computation burden of three-dimensional MUSIC method. This method obtains source azimuths by one-dimensional search without prior knowledge of source ranges and depths. So, computational complexity of proposed method decreases exponentially compared with that of maximum likelihood (ML) and three-dimensional MUSIC. Results from simulations and lake experiments turn out to be in close agreement with theoretical analysis.