Study of multi-Band circularly polarized microstrip antenna with compact size

In some satellite navigation receiver systems, there is not enough space to settle several antennas for multi-port multi-band application generally. A triple-deck circularly polarized antenna with three ports for receiving and sending satellites signal is studied in this paper. The design idea in this paper is to place several single-feed microstrip antennas layer by layer for saving space. All patch antennas are probe-fed, and the probe connected with the upper patch goes through the clear hole in lower substrates. The structure of the multi-band antenna is investigated thoroughly. How to tune this kind of antenna is a big problem in application, and one special parameter is given to adjust the performance of the antenna. The designed triple-deck antenna works at the bands of GPS, BDS and 1.66 GHz independently. The formal two bands are RHCP, and the third band is LHCP, so it can receive and send signals at the same time. Both simulated and measured results show that all three working bands can cover the system use differently. Axial ratio less than 3 dB at center frequency is obtained, and absolute gain at center frequency is more than 4 dBic. The advantages of this antenna are compact in size for multi-port multi-band use and easy fabrication.