A Novel Double-Layer Rectangular Microstrip Antenna

In this paper, a novel double-layer rectangular microstrip antenna (DL-RMSA) is presented. It is fed by a microstrip line along the non-radiating edge of a bottom patch. Three or more slots are cut in the parasitic patch, respectively, in order to suppress TMm0 mode radiation and cross polarization. The simulated and measured results indicate that the novel antenna presents the advantages of wider frequency bandwidth as compared to the classic DL-RMSA. Furthermore, this design simplifies feeding network and increases radiation efficiency in array applications. A small array of 8x8 elements is fabricated and tested. Excellent results are observed, including low cross-polarization and high radiation efficiency.