Low‐profile circularly polarized GNSS antenna

In this article, we present a low‐profile and low cost antenna for GPS (L 1 –L 2 –L 5 ), Galileo (E 5 –E 1 –E 2 ), and Glonass (G 1 –G 2 ) standard. This antenna is a dual‐feed planar patch antenna with four slots to achieve dual‐band operation. The radiating element is fed by a wideband 90° quadrature hybrid coupler to obtain circular polarization on the both bands. The quadrature feeding is achieved using a three‐branch‐line hybrid coupler. The return loss bandwidth of the system (S 11 ≤ −10 dB) is 22% in the lower band and 14% in the upper one. The axial ratio (AR) bandwidth in broadside direction (AR= 3 dB) is 20% in the lower band and 11.3% at the upper one. The antenna gain is 6 and 8.4 dBi in the normal direction at the central frequency of 1.23 and 1.6 GHz, respectively. The total dimensions of the antenna are 170 mm 2 with a thickness of 7.524 mm. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2811–2814, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27175