Solving an acoustic wave equation using a parabolic approximation is a popular approach for many available ocean acoustic models. Commonly used parabolic equation (PE) model programs, such as the range-dependent acoustic model (RAM), are discretized by the finite difference method (FDM). Considering the idea and theory of the "split-step" parabolic approximation, a discrete PE model using the Chebyshev spectral method (CSM) is derived, and the code is developed. We use the problems of two ideal fluid waveguides as examples, i.e., one with a constant sound speed in shallow water and one with a Munk sound speed profile in the deep ocean. The correctness of the  discrete PE model using the CSM to solve a simple underwater acoustic propagation problem is verified. 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. However, the proposed method has a longer running time than the finite difference discrete PE program . Thus, it is suitable to provide high-precision reference standards for the benchmark examples of the  PE model.
Solving an acoustic wave equation using a parabolic approximation is a popular approach for many existing ocean acoustic models. Commonly used parabolic equation (PE) model programs, such as the range-dependent acoustic model (RAM), are discretized by the finite difference method (FDM). Considering the idea and theory of the wide-angle rational approximation, a discrete PE model using the Chebyshev spectral method (CSM) is derived, and the code is developed. This method is currently suitable only for range-independent waveguides. Taking three ideal fluid waveguides as examples, the correctness of using the CSM discrete PE model in solving the underwater acoustic propagation problem is verified. The test results show that compared with the RAM, the method proposed in this paper can achieve higher accuracy in computational underwater acoustics and requires fewer discrete grid points. After optimization, this method is more advantageous than the FDM in terms of speed . Thus, the CSM provides high-precision reference standards for benchmark examples of the range-independent PE model.
R
available
existing
R
"split-step" parabolic
wide-angle rational
R
We use the problems of two
This method is currently suitable only for range-independent waveguides. Taking three
D
i.e., one with a constant sound speed in shallow water and one with a Munk sound speed profile in the deep ocean. The correctness of
A
correctness of using the CSM
R
using the CSM to solve a simple
in solving the
R
finite difference discrete PE model, the proposed method
RAM, the method proposed
R
has a
can achieve
R
the calculation of underwater acoustic propagation in a simple marine environment
computational underwater acoustics
R
However, the proposed method has a longer running time than the finite difference discrete PE program
After optimization, this method is more advantageous than the FDM in terms of speed
R
it is suitable to provide
the CSM provides
D
the
A
range-independent