Implementation of a Reflectarray Antenna with Isofiux Beam Based on Gauss-legendre Quadrature Technique

In this paper, a fast and accurate reflectarray synthesis method based on the Gauss-legendre quadrature technique is introduced. Thanks to the employment of this technique, the far-field radiation pattern of the antenna could be calculated with a high accuracy in terms of the Gaussian points on the aperture. It is shown that without losing accuracy, the number of the Gaussian points can be selected much less than regular points in conventional synthesis, leading to speed up the far-field calculations. Different from conventional methods, such as the Fast Fourier Technique (FFT), the proposed method has the potential to be used in a shaped reflectarray and reflectarray with unequi-spaced unit cells. Because of acceptable speed factor of the proposed method, it is very suitable for implementing reflectarray with a shaped beam radiation pattern. We use it as a computational core of an evolutionary algorithm to design of a reflectarray with isoflux beam.