Reduction in Cross-Polarized Radiation of Microstrip Patches Using Geometry-Independent Resonant-Type Defected Ground Structure (DGS)

A new method of suppressing cross-polarized (XP) radiation using resonant-type defected ground structure (R-DGS) on microstrip antenna has been proposed in this communication. A linearly shaped full wavelength R-DGS has been proposed and experimentally verified for different microstrip geometries. The design is supported by thorough investigations on the physical interaction between R-DGS and XP generating fields. Unlike previously explored nonresonant-type defects, this new approach is independent of patch geometry. A consistent suppression of the H-plane XP fields well below -30 dB for different patch geometries has been experimentally demonstrated.