Reconstruction of surface errors of the metallic waveguide based on electromagnetic scattering theory

First, the fractal model of surface errors was constructed by means of the Monte Carlo method, and the source term and spectral amplitude of surface errors were calculated. The reconstruction model of surface errors was then established. The non-differentiable problem of the fractal model was solved by the fractional differential theory. To verify the accuracy of proposed models, a waveguide filter was manufactured. The reconstruction results obtained by the fractal function model were compared with the measured results, and a comparison of the results obtained by different reconstruction models proves that the fractal function is optimal in modelling.