Fast Analysis for Aperture Efficiency and Radiation Patterns of Reflectarray Antennas

Abstract

In the design procedure of the reflectarray antennas, the fast analysis of the aperture efficiency and radiation patterns is necessary before manufacture to forecast the antennas performance proximately. The fast calculation of the aperture efficiency and radiation patterns of reflectarray antennas is presented in this paper. A more general approach is introduced to calculate the spillover efficiency of a reflectarray. Meanwhile, the taper efficiency of the reflect-array is calculated with a unified set of equations. Two different fast approaches of the radiation patterns analysis-array theory and aperture field are described, and the discrete Fourier transform is applied to speed up the computational speed. On the basis of these derivations, numerical results of a Ku band reflectarray with offset feed are presented to show the performance of these approaches, and to provide the guidelines for designing and analyzing reflect-array antennas.