Contour-FFT based Spectral Domain MBF Analysis of Large Printed Antenna Arrays

TL;DR

This paper introduces Contour-FFT, a fast spectral-domain method for efficiently evaluating reaction terms in large printed antenna arrays, significantly reducing computational complexity while maintaining accuracy.

Contribution

The paper presents a novel Contour-FFT technique that accelerates spectral domain analysis of antenna arrays using contour integration and FFT, independent of element complexity.

Findings

Achieves order N log_2 N complexity for substrate-related reaction terms

Provides accurate results with excellent agreement to reference solutions

Applicable to both regular and non-regular antenna arrays

Abstract

A fast spectral-domain method is proposed to evaluate the reaction terms between the Macro Basis Functions in regular and non-regular arrays made of identical printed antennas. The presented technique first exploits the filtering capabilities of the Macro Basis Functions in the spectral domain. The method is then strongly accelerated with the help of a newly formulated Fast Fourier Transform-based technique, which is applicable to a contour integration in the complex plane. We name the method as Contour-FFT or C-FFT. Besides an effective homogeneous medium term treated with multipoles, a computational complexity of order N log_2 N is achieved for the the tabulation of substrate-related reaction terms for any possible relative positions. The complexity of the proposed method is independent from the complexity of the elements. Numerical results obtained with the proposed method are compared with those from a pre-validated reference solution based on the traditional Macro Basis Functions technique; an excellent agreement is observed.