Effect of window function on absorbing layers top boundary in parabolic equation

Constructing parabolic wave equation model, with the algorithm of discrete mixed Fourier transform, has become the mainstream approach to describe the atmospheric duct. To determine the absorption layer top boundary of parabolic equation is the significant step of the step calculation process. This paper discusses on the relevant problems about setting window function for absorption boundary. Firstly, we proved that two commonly used window: Tukey window and Hanning window are in the same coincident configuration mathematical expressions. Secondly, we put forward some new window functions and verify their availability under a numerical example. And we draw a conclusion on some conditions which should be added to the absorbing top boundary and discussed the effect on one-way path loss in different window functions. Numerical results showed in the paper could verify that the condition of window function we proposed is right.