A wideband microstrip array antenna with unique dumbbell shaped aperture coupled radiating elements

A wideband 2/spl times/2 planar microstrip antenna array with dual circular polarization is proposed for serving mobile satellite communications. The basic array element is an optimized diagonal slotted diamond shaped dumbbell aperture fed patch antenna for improved axial ratio and impedance bandwidth performance. A 2:1 impedance bandwidth of 23% and 3 dB axial ratio bandwidth of 19.2% with a circular directivity of 14.2 dBi is achieved with the optimized array structure. The above features make it an ideal circularly polarized structure for addressing wideband applications as required in mobile satellite communication systems.