A Comparison Between Fast Fourier Transform and Matrix Pencil Method for Spectral Integration Calculation

The spectral integration is a critical step in the near field to far field transformation. The calculation of spectral integration is usually implemented by using Fast Fourier Transform (FFT). FFT is efficient, but it often can not calculate the phase of the plane wave spectrum accurately. In order to achieve accurate phase calculation, this paper proposes to calculate the spectral integration by using the Matrix Pencil Method (MPM). Simulations are performed to compare the efficiency and accuracy of MPM and FFT. It is found that MPM significantly improves the accuracy with acceptable CPU time consumption.