A high performance dual frequency microstrip antenna for Global Positioning System

The Global Positioning System (GPS) has been used in a variety of applications for which new and more restrictive requirements in the design of the receiving antenna have been introduced. In particular, for high-precision GPS applications, a receiving antenna with superior rejection to multipath signals is required. Furthermore, in order to satisfy the demanded precision and reliability, a high performance GPS antenna must be capable of operation at the two GPS frequencies (1.57542 GHz and 1.2276 GHz). One effective design (see Boccia, L. et al., Microwave and Optical Technology Letters, 2001) demonstrates that consistent multipath mitigation can be obtained with a single frequency shorted annular patch. A stacked shorted elliptical patch, operating at the two GPS bands, is presented. The antenna combines the shorted ring radiation properties, which have proved to comply adequately with multipath mitigation requirements, with dual frequency operations, resulting in a compact high performance dual frequency GPS antenna.