Design Of Multi-Mode Navigation Antenna Based On EBG Structure

Satellite navigation system is an important base installation to the national economic construction, which is an emerging industry that following the internet industry, and will provide physical link in seamless integration between the Internet of Things and the internet in the future.The mainstream of thesatelite navigation system in the word inclued of beidou satellite navigation system, GPS, Galileo navigation system, and the GLONASS navigation system. The satellite receiving terminal of the multiple navigation system that can be compatibled at same time has been a hot reaserch point.In order to let the antenna working in a state of multimode, the requirement of multimode antenna is becaming more and more important.In this paper, we have introduced the radiation mechanism and analysis methods of microstrip antenna, and also reaserched the characteristic of surface wave, phase surface band gap and polarization controlling. The main works are following as below:1. Combined with the theory of microstrip antenna, we designed a single dual-mode GPS antenna with coaxial feed by using technology of patch edge loading. The simulation shows:the antenna possesses an impedance bandwidth of 50 MHz at the frequence L1 (1568MHz), and the gain can reach to 2.204dB at 90 angle, the axial ratio was smaller than 3db.2. We introduced EBG stucture based on the single dual-mode structure, which have improved the performance of antenna for the magnetic characteristic. The simulated and fabricated results show:the performance of the antenna has been improved from 50MHz to 85MHz, the 3dB bandwidth of axial ratio has improved either,the back lobe of the antenna has been controlled at same time.3. Based on the two antenns above, we designed a dual-band multi-mode satellite navigation antenna, and the frequence of antena is covering of B1, B3 of bedou navigation system, L1 of GPS, E6 of Galileo navigation system. The simulation and fabrication show:the varity indexes of antenna can meet the navigation signals, the bandwidth of high and low frequency both improve more than 40MHz,3dB bandwidth of axial ratio is more than 15MHz, the main lobe of antenna also becoming wider, and elevation angle range of Odb gain reachs to 180 degrees.