The Research Of Half Space Coverge Beamforming Array And RF Front-end

With the development of modern civilian communications and military communications,more and more phased array antennas have been adopted.In a variety of phased array antennas,the half-air-domain beam forming array is widely used for its large coverage area in the geostationary-platform communication network.Usually the bandwidth of microstrip antenna is narrow and circular polarization can only cover a certain angle range(microstrip's normal direction).Therefore,it is difficult to design the antenna with wide frequency band and keep its circular polarization characteristics in a wide enough angle;on the other hand,in the limited number of RF front-end multi-channel,it is easy to lead the interference coupling problem while achieving specific gain in different directions of the semi-air space and so as the traditional phased array RF front-end system,and how to solve these problems is a technical key point also.In this paper,we mainly study and analyze the half-air-covered phased array and RF front-end.In the aspect of RF front-end,we simulated the coupling problem between the multi-channel,and analyzed the coupling effects between multi-channel qualitatively,at the same time,a series of target solutions are put forward in this thesis.In view of antenna,by increasing the thickness of microstrip antenna and by using air layer to broaden the antenna bandwidth.the balanced four-feed method is adopt to achieve a good circular polarization,and ensure that the antenna unit can achieve an excellent circular polarization characteristics within the angle range of ± 30 °.The research content of this paper is to design a three layer switching antenna array structure,to guarantee antenna gain can reach a half coverage area in the airspace while in a limited number of channels,and to ensure a good circular polarization.At the same time,the horizontal array is simulated so that the horizontal gain meet the requirements also.This paper mainly has six chapters: The first chapter mainly introduces the research background,the development status and the main structure of the paper and demonstrates the necessity of the research of this paper.The second chapter mainly introduces the basic theory of microstrip antenna and antenna array,and selects a small,multi-angle circular polarization,high gain and suitable array antenna,and analyzes the RF front-end transmitter and receiver The common structure and the main technical indicators and select a suitable for this design of the RF front-end system.The third chapter mainly designed a set of RF front-end transceiver system and select the appropriate chip for link simulation,and simulation of RF front-end multi-channel coupling between the situation and put forward a solution.The fourth chapter designs a new type of antenna element,and carries on the modeling and simulation,and then designs to increase the conductor wall to carry on the isolation between the antenna and carries on the physical test and so on.In the fifth chapter,the scheme of double antenna and conductor wall is simulated and tested actual object.At the same time,the antenna array is designed and simulated to achieve the desired effect.The sixth chapter is the summary of the full article and the prospect of the next works.