Design of Small CRPA Arrays for Dual-Band GPS Applications

This paper proposes the design of small CRPA arrays for dual-band Global Positioning System (GPS) applications. The array consists of five elements and is mounted on a circular ground platform with a diameter of 15-cm. Each antenna element has a coupled feed structure and consists of a feed patch and two radiating patches for dual-band operation. An external chip coupler is utilized for a broad circular polarization (CP) bandwidth, and its measured characteristics are taken into account in our simulation for more accurate performance estimation. Detailed parameters are optimized by using a genetic algorithm (GA) in conjunction with the FEKO EM simulator. The optimized antenna is fabricated on a ceramic substrate, and its performance is measured in a full anechoic chamber. Furthermore, a field test is also conducted to verify the signal-to-noise ratio (SNR) for real GPS satellite signals. The results prove that the proposed array is suitable for use in GPS CRPA applications