New Generation Of Mobile Communication Base Station Antenna System

With the rapid development of wireless communication, mobile subscribers have increasing requirements of the system capacity and communication quality. Therewith, the design of the base station antenna, which is a vital component of a wireless system, should take into account many factors. In the next generation of wireless communication, the application of MIMO technologies increases the system capacity linearly with the minimum number of transmit and receive antennas. As the MIMO system implies multiple antennas in both transmit and receive sides, the design of multiple antennas becomes very important in the next generation of wireless communication.As for the base station antenna, the requirement of its volume, weight and cost is not as strict as that of the mobile terminal antenna. Therefore, plenary use of the space of the base station to make the antenna satisfy various demands should be considered when designing the base station antenna. In the next generation of wireless communication, the base station antenna should have these functions: integration of different diversity methods to release multi-path fading, beam-downtilt to reduce co-channel interference, beam-forming to optimize coverage.In this dissertation, switched parasitic pattern diversity yagi-uda antenna array used for the base station has been illustrated after the introduction of MIMO technologies and the analysis of the base station antenna design for next generation of wireless communication. This switched parasitic yagi-uda antenna uses a yagi-uda antenna as its prototype, and can change radiation pattern by the control of RF switch which is placed at the center of its reflector. The characters of this antenna lie in three points: using yagi-uda antenna to obtain antenna gain through the radial direction; making full use of the space of the base station along the Z-axis direction to get array gain; arranging the antenna array properly to achieve pattern diversity in azimuth plane. This pattern diversity antenna has been used as the base station antenna in the MIMO experimental system and several results have been obtained. From the measured and experimental results, we can see that this antenna has good performance.