Theoretical analysis of compact and broad-band microstrip antenna with gap-coupled parasitic elements along the non-radiating edges

Wideband performance has been obtained from a microstrip patch antenna by using parasitic patches coupled along the nonradiating edges. The concept of the coupled microstrip line model is extended for the theoretical interpretation of the input impedance of a two-patch gap coupled along the nonradiating edges. It is concluded that the theory presented here predicts the impedance behavior of a rectangular patch antenna loaded with a parasitic element within tolerable limits.<>