Research On The Technologies Of Conformal Multi-beam Satellite Signal Receiving System

Using low earth orbit satellite(LEO)to exchange information with ground is a research hotspot in both military field and commercial world,which is beneficial for controlling satellite launches costs,shortening telecommunication distance and reducing launching power.LEO's data broadcasting is a typical application of LEOS.It refers to a usage scenarios that directly pushing low earth orbit data to receiver via special satellite channel.The characteristics of LEO lead to the problem of weak signal,low elevation and high dynamic when signals reaches receiving terminal.In order to receiving all the valuable data at maximum visibility,satellite receiving system should be able to receive weak satellite signals in wide airspace.It is difficult to get a good reception performance at low elevations using traditional antenna.By contrast,the combination of Conformal Arrays Antenna(CAA)and Digital Beam Forming(DBF)is an excellent way to solve the problem through producing sharp beam form pointing at any specified direction.It is possible to realize high-performance signals reception of LEO receiving system using Conformal Arrays Antenna with Digital Beam Forming.But there are a lot of problems to be solved to take a technical advantageous shape in key performance indexes such as high sensitivity and wide space.The paper focuses on optimizing acquisition method and improve the gain of antenna array to achieve the goal of high receive ability.It solves the following key technical problems:(1)Acquisition of low earth orbit broadcasting signals.The research constructs criterions to maximize the gain of acquisition by evaluating the performance of acquisition methods.We get a satisfactory acquisition result through optimizing traditional acquisition methods via analyzing the features of LEO broadcast signal.(2)The gain improvement and control via the DBF in CAA.The study discusses the way to choose structure of CAA after establishing the criterion of weighted value based on theory and practice.In addition,it determines the schema of a rray and the arrangement of array element by comparing alternatives' simulation results.In the end of the thesis,the paper describes the prototype of receiving system.We build a test system to test the performance of the receive system.The results prove the practice and effectiveness of these technologies.The study provides valuable preferences for the research and development of receiving system.