 The test results show that compared with the finite difference discrete PE model, the proposed method in this paper has a higher accuracy in the calculation of underwater acoustic propagation in a simple marine environment and requires fewer discrete grid points.
<clarity>  The test results show that compared with the finite difference discrete PE model, the proposed method in this paper has a higher accuracy in the calculation of underwater acoustic propagation in a simple marine environment and requires fewer discrete grid points.
 The test results show that compared with the finite difference discrete PE model, the proposed method in this paper can achieve higher accuracy in the calculation of underwater acoustic propagation in a simple marine environment and requires fewer discrete grid points.