Efficient analysis of multi-resonant periodic structures for the improved analysis and design of reflectarray antennas

Abstract

Abstract-In order to design reflectarray antennas within reasonable CPU times, fast and accurate numerical tools for the analysis of periodic multilayered structures are required. In this paper the method of moments in the spectral domain (MoM-SD) based on multilayered Green's functions (MGF) is applied to the analysis of periodic structures containing multilayered stacked patches in the unit cell. These multiresonant cells are potential elements for the design of reflectarray antennas. In the paper we show that the use of basis functions with edge singularities in the approximation of the current density on the patches leads to important computer memory and CPU time savings in the analysis of the periodic structures. Also, a rational fitting technique is introduced which makes it possible to obtain closed-form expressions for the scattering matrix of the periodic structures in terms of the dimension of the patches used to adjust the phase of the reflectarray elements.

Design of a reflectarray antenna at 300 GHz based on cells with three coplanar dipoles

“…For each element, the dipole lengths are adjusted by using a zero finding routine that iteratively calls the analysis routine [3], as described in [4]. The design is completed in 4 hours and 23 minutes on a laptop with Intel Core Í5-2540M at 2.60GHz and 8GB of RAM.…”

“…However a more accurate design will require to account for the real angle of incidence at each reflectarray element. An efficient technique based on Spectral-Domain Method of Moments (SD-MoM) has been implemented for the analysis of reflectarray antennas made of a single layer of metallizations composed of cells with three parallel dipoles [3].…”

“…The analysis technique proposed in [3] has been used in the present work to carry out a more accurate design of a reflectarray antenna using the reflectarray elements defined in [2], by accounting for the angle of incidence in each reflectarray element and assuming local periodicity. Thanks to the efficiency of the analysis technique, the design is completed within reasonable CPU times in a conventional laptop.…”

Wideband unit-cell based on liquid crystals for reconfigurable reflectarray antennas in f-band

“…The reflectarray cell was analyzed by in-house software tool based on Spectral Domain MoM [6], which has been validated by comparing the results with those obtained by CST [5]. In this first iteration, considering the nominal properties of the LC, a phase range of 360º was obtained in a bandwidth (defined by an error of ±20º [3]) from 117 to 130 GHz (10.5 %).…”