Single-fed Circularly Polarized Antenna Element With Reduced Coupling for GPS Arrays

A single-fed circularly polarized stacked patch antenna is proposed to cover all GPS bands, including the E5a/E5b band for the Galileo system. The small aperture size (lambda/8 at 1176 MHz, the L5 band) makes this antenna attractive for small GPS arrays. Also, in contrast to previous GPS antennas, the presented design uses a single feed for circular polarization. In this paper, we present the design procedures and performance of the designed GPS antenna and discuss issues relating to coupling between array elements. Modifications to reduce coupling are then presented.