Novel design of multilayer wideband shorted annular stacked patch antenna for GNSS application with dual layer strip lines fed

Novel design of compact circularly polarized shorted annular stacked patch antenna has been proposed for global navigation satellite system in this study. The antenna has been designed to operate for the satellite navigation frequencies, including GPS, GLONASS, Galileo and Compass (1100–1600 MHz). Dual-layer strip lines that being composed of one broadband 180° hybrid and two wideband 90° hybrids are introduced as feeding network. As a result, the antenna has a 50.8% 10-dB return loss bandwidth from 1.1 to 1.85 GHz, and 45.5% 3-dB axial ratio bandwidth from 1.07 to 1.7 GHz, respectively. The designed antenna occupies a compact size of 70 mm × 70 mm × 28.5 mm. In this study, shorted annular stacked patch is introduced to obtain stable gain bandwidth, broad beam width characteristics, and good axial ratio at low elevation.