【Title】A two-way marching coupled-mode method for range-dependent propagation

【Author】LUO Wenyu~1 ZHANG Renhe~1 SCHMIDT Henrik~2 (1 Institute of Acoustics,Chinese Academy of Sciences Beijing 100190) (2 Department of Mechanical Engineering,MIT Cambridge,MA 02139 USA)

【Abstract】An efficient,accurate,and numerically stable coupled-mode solution is presented for acoustic propagation in a range-dependent waveguide.This method is numerically stable due to the appropriately normalized range solutions introduced in the formulation.In addition,by combining a forward marching and a backward marching,this method provides accurate solutions for range-dependent propagation problems,especially those characterized by large bottom slope angle and/or high impedance contrast between water and the bottom.Furthermore,this two-way solution also provides high efficiency,which is achieved by applying the single-scatter approximation.Numerical examples are also provided to demonstrate the efficiency,accuracy, and stability of this method.