Circular polarized planar elliptical antenna array

A low-profile planar microstrip antenna array with elliptical elements is proposed, fabricated, and measured. The operating bandwidth of the antenna is about 1 GHz (5.3-6.4 GHz). The impedance matching, radiation pattern and polarization are analyzed numerically and compared to measurements. This antenna provides a two main directive radiation components (front and back), and circular polarization (CP). Each elliptical element has an inner counter-elliptical slot which provides a way to easier match the antenna in impedance and polarization. The number of elliptical elements can be scaled to increase or decrease the antenna gain and the three parameters of the inner slot of the elliptical elements (radius, ratio and rotation) can be scaled for impedance and polarization matching over the band of interest.