Full-Wave Analysis of Layered Aperture Arrays

Abstract

The rigorous numerical-analytical approach has been developed and used for study of the periodic aperture arrays containing multiple dissimilar apertures of complex shapes in stratified medium. The analysis method is based on the solution of the system of integro-differential equations by Galerkin method with the entire domain basis functions explicitly accounting for the field singularities at the edges of the whole aperture except corners. An analytical treatment of the Green's function convolutions with the basis and test functions provides an efficient regularization and rapid uniform convergence of the solutions. Thickness of conducting screen has been taken into account with the aid of the approximation for effective aperture dimensions. The characteristics of the quasioptical slot arrays simulated by the developed method are in excellent agreement with the results of measurements and alternative simulations. An extensive parametric study of several aperture array configurations has been performed to explore properties of the single layer array arrangements with multiple apertures of complex shapes in a unit cell and stacked layered arrays. Effect of the aperture shape on the array performance and the physical mechanisms underlying the transverse magnetic wave resonances and Luebbers' anomaly in the two-layer arrays are discussed in detail.