Research Of GNSS Satellite Navigation Circular Polarization Antennas

With the development of the satellite navigation techniques, the industry is changing from the traditional GPS system to the Global Navigation Satellite System(GNSS), which is constituted of the GPS, the Compass, the Galileo and the GLONASS. Each system has its own merits. Therefore it is inevitable to develop the techniques compatible with multiple satellite navigation system to improve the positioning accuracy and freedom from the constraints of a single system. The circularly polarized antenna, as one of the important parts of the system, must be able to compliant multiple systems and receive multiple satellite signals. This dissertation studies the circularly polarized antenna design theory and the techniques for the GNSS applications.Firstly, the radiation principle, the characteristics and the parameters of the circularly polarized microstrip antennas are introduced, the existing design methods of circularly polarized microstrip antennas, especially of the multi-frequency circularly polarized microstrip antennas, are systematically summarized in this dissertation.Secondly, a circularly polarized microstrip antenna with a Wilkinson power-divider and a ceramic substrate is proposed. It has a good performance. And the simulated results show that the proposed antenna is found to deliver the 10-dB impedance bandwidth of 44.21%, the 3-dB axial ratio bandwidth of 37.8%, the maximum gain of 3.81dB and other fine performance.Finally, a multi-aperture-couple circularly polarized antenna with sequential rotation feeding and a ceramic substrate is proposed. The geometry of the feed network is simple, and the simulated results show that the proposed antenna is found to deliver the 10-dB impedance bandwidth of 4.2%, the 3-dB axial ratio bandwidth of 1.08%, the gain of 6dB and other fine performance.