Research Of Dual-Polarization Base Station Multi-Antenna For MIMO

As the mobile communications business escalates in the capacity and quality, the working band in mobile communication is very crowded. To meet the high-speed, high-capacity business needs, we use the limited frequency resources effectively with advanced technology and overcome the multipath fading of the high-speed data in wireless channels. For the purpose MIMO technology is proposed and has become a hot research spot in the area of wireless communications. MIMO technology can greatly enhance the capacity of the system and has been considered as one of the most competitive technologies in the future wireless communications.The research of base station multi-antenna is essential to achieving MIMO systems. Base station antenna is not restricted in space and weight and easy to achieve multi-dimensional diversity. Many technologies and measures to improve the quality of system communication are achieved by the base station antennas. Higher requirements of the environment needs base station multi-antennas to achieve diversity gain and multiplexing gain in the minimum space.A double-H type slot antenna such characteristics as dual-polarization is designed by using slot-couple technology and two-gap-couple feed technology. It is simulated and tested. The tested data coincide well with the simulation results. According to the test, the horizontal polarization gain is 8.8dBi, the vertical polarization gain is 8.9dBi and the cross-polarization isolation is less than -40dBi. It achieves such features as high gain, high isolation and dual-polarization. On the basis, a space-adjustable quaternary multi-antenna array is designed. The antenna array and mutual coupling are analyzed. For different array element spacing each unit port isolation, cross-polarization isolation and the far-field radiation character -istics in frequency 2.14GHz are tested and analyzed.The optimal array spacing is given as d=0.86λwhich provides a good platform for the high-performance MIMO wireless systems..Finaly, the research work of this paper are summaried and the further study is discussed.