Corporate‐fed advanced microstrip arrays with improved cross‐polar isolation: Design and engineering using DGS‐integration techniques

Abstract

Integration of defected ground structure (DGS) with a single microstrip patch has been a very successful technique in minimizing its inherent issue of cross-polarized (XP) radiations. But, in many of the applications, arrays of patches are often used for which additional constraints appear along with additional sources for XP radiations. Thus, the array needs other major considerations and engineering which have been addressed in this paper for the first time. It explores the DGS in an optimal way to design a 2 × 2 microstrip-fed sub-array which can be used as the building block for large sized arrays. The mode of field launching from a typical coaxial medium to microstrip line has been critically studied with some new insights. A set of X-band sub-array designs have been experimentally investigated with a promise of suppressing H-plane XP fields by about 10 dB consistently over the entire operating band. This work should find enough scope of practical applications where low XP radiation in the orthogonal plane is an essential requirement of corporate-fed microstrip arrays.