Asymmetric and Compact DGS Configuration for Circular Patch With Improved Radiations

This letter explores improved tuning of defected ground structure (DGS) geometries for circular patch with twofold objective: to minimize the defect size by strategic shaping and deployment and, at the same time, to maintain the highest order of achievable suppression of cross-polarized (XP) radiations. Relative merits and demerits of the earlier designs have been accounted for, to justify the need of further comprehensive improvement. The DGS dimensions in several cases appear as a limiting factor, especially in arrays. This letter resolves the same and reduces the size by at least 35%. Asymmetrically configured designs have been emphasized with a view to addressing the asymmetry in modal fields. They are examined in X-band and experimentally verified with a promise to achieve 16-18 dB XP suppression over H-plane, which, to the best of authors' knowledge, is the maximum reported suppression so far.