On The Directional Panel Antennas And Diplexers For The Indoor Distributed Antenna System

With the rapid development of mobile communication technology, mobile communication system coverage has been maturing in the outdoor. Relative to the widely outdoor signal coverage,the indoor signal coverage is still inadequate. On the background of China's rapid development of urbanization, the high density of urban construction makes the communication environment of wireless signal become more complex. The outdoor mobile communication base stations are not adequate for the current demands of mobile communication. In order to enhance the communication quality for indoor users, communication operators need to increase the indoor signal coverage of mobile communication network and build the indoor distribution system. As a result, this thesis focuses on the application of directional panel antenna for the indoor distribution system.Based on the research of the rectangular wide slot antenna, a dual-wideband directional panel antenna for indoor distributed application is introduced. The proposed antenna is designed on the basis of planar printed wide slot antenna by adding a reflection ground. It can work on 698MHz-960MHz&1710MHz-2690 MHz covering all the frequency bands for current mobile communication application. The simulation analyses have been made to study the characteristics of the proposed antenna. The mismatched impedance caused by the introduced reflection ground is modified by adding the metal coupling baffle. According to the final optimized models, the antenna is fabricated and measured. The simulated and measured results show a good agreement with each other. It is shown that the proposed directional panel antenna obtains |S11|<-10 d B and more than 5d Bi gain in the 698MHz-960 MHz band while |S11|<-15 d B and 7-9d Bi gain in the 1710MHz-2690 MHz.Based on the research of broadband dipole antenna, two broadband dual-polarized printed dipole antennas are designed with one working in 698MHz-960 MHz and the other in 1710MHz-2690 MHz. With the basic knowledge of the filter and the working principle of the diplexer, a diplexer working in the 698MHz-960 MHz and 1710MHz-2690 MHz bands is proposed. And then, a dual-polarization dual-wideband directional antenna in the 698MHz-960 MHz and 1710MHz-2690 MHz is designed on the previous works. According to the final optimized results, all the designed antennas and diplexer are fabricated and measured. Simulated and measured results show that the dual-polarization dual-wideband directional antenna is |S11|<-15 d B in the whole working band with the gain above 7d Bi in 698MHz-960 MHz band and 7-9d Bi in 1710MHz-2690 MHz band. The simulated and measured results show that the designed antenna has stable radiation patterns and low cross polarization ratio in the working band and can be widely use in the indoor distribution system.