Segmented half-loop antennas for vehicular GPS applications

A new type of circularly-polarized antenna is proposed which consists of two orthogonal segmented half-loops. The segments are interconnected with printed circuit reactive elements, which allow one to tune the reactances in order to achieve both a desirable pattern and a good match at the input port. A right-hand circularly-polarized antenna is designed for GPS L1 operation, which achieves a gain about 3.6 dBic at zenith, with a gain variation less than 1 dB up to 55°.