Proximity Feed Broadband Circularly Polarized Circular Sectoral Microstrip Antenna

Novel design of circularly polarized Circular Sectoral Microstrip antenna using cross slot is proposed. To obtain circular polarization systematic study is carried out. This study aimed at degeneration of orthogonal modes using cross slot for circular CS-MSA Microstrip antenna. The parametric study is reported for impedance and axial ratio bandwidth for various cross slot dimensions. Embedding the cross slot on the circular CS-MSA generates two orthogonal mode; one is along radial direction and other along circumference. The length and position of cross slot for desired circular CS-MSA radius decides separation between two resonance frequency corresponding orthogonal modes. The reported structure gives impedance band of almost 600 MHz (> 54%) and axial ratio bandwidth (7.69%) around 1100 MHz. The proposed antenna gives broadside gain 8 dBi. Also the paper elaborate technique to change sense of rotation for circular polarization of proposed structure.