Design Of Satellite Communication System Based On OFDM And Realization Of Software Radio

In order to achieve high quality communication services in any scenario,the establishment of an integrated air-space information network has become a current research.hotspots,of which satellite communications are an important component.However,satellite channels have problems such as frequency selective decay and band resource constraints,while orthogonal frequency division multiplexing(Orthogonal Frequency Division Multiple,OFDM)is a special multi-carrier transmission technique that is resistant to frequency-selective decay and has high spectrum utilization.The use of OFDM transmission technology in satellite communications is of great significance.At the same time,because the traditional communication equipment is designed for fixed communication function,its structure is similar but its interoperability and flexibility are relatively poor.In order to address this problem,this project proposes the use of highly reconfigurable and flexible software radio platform.The main work of this paper is to design and implement a satellite communication system based on OFDM technology.Firstly,the modulation and demodulation principles of OFDM technology are analyzed,and various types of channel decay are described,and the C.Loo,Corazza and Lutz satellite channel models are briefly reviewed.Then,the physical layer of satellite OFDM is planned,and the Least Squares(LS)is studied.channel estimation algorithm,and modeled the system in MATLAB and analyzed its performance under AWGN channels;and Simulation of C.Loo,Corazza and Lutz satellite channel models using software based on satellite channel characteristics The Markov state transfer process in the Lutz channel model is analyzed.Subsequently,a software radio platform based on Zed Board and AD9361 composition is evaluated,considering the three software The strengths and weaknesses of the radio design solution were finalized using the Simulink modular solution to implement this system.Finally,the OFDM-based satellite communication system was implemented on a software radio platform consisting of Zed Board and AD9361.and its key technologies for implementation.By analyzing the experimental results of integrated channel transmission under different atmospheric environments,it is shown that the design of this OFDM technology satellite communication system Success,this hardware platform functions normally.This system is of great value and significance for the study of OFDM system based satellite communication and software radio product development.