Theory and applications of chirality in microstrip antennas

Abstract

The aim of this study is to analyze radiation from surface currents lying on an interface between a grounded, planar, lossless, isotropic, chiral slab and a simple lossless dielectric half-space. An eigenvalue-eigenfunction approach, specifically the Ohm-Raleigh method, is employed to obtain a modal expression for the full-wave Green's function. By using asymptotic techniques, the far-field electric field is found for an elemental point dipole source. The theory is directly applicable to radiation from a printed circuit antenna having a chiral substrate. Current research efforts show that under certain circumstances, the introduction of chiral materials as substrates of microstrip antennas offers novel radiation properties over achiral microstrip antennas. A number of representative antennas are analyzed with respect to radiation pattern, main beam position, and directivity.