The Research Of Satellite Communication Channel Markov Model And SIMULINK Realization

In satellite communication systems, there are many external factors affecting the signal transmission which may cause the satellite communication systems have complex and variable channel propagation characteristics. And the propagation characteristics of the channel directly affect the communication qualities and the performance of system. With the development of satellite communication technology, the frequency of wireless communication is increasing; the influences of atmospheric environment are becoming more and more obvious. Based on the research of the mobile satellite channel measurement and channel modeling in the domestic and foreign, the satellite communication channel Markov model is established considering the influence of atmospheric environment and the visual simulation of the satellite communication system is realized in the SIMULINK platform. The paper mainly includes the following points:(1) According to the different sources of signal attenuation, the channel environment includes the atmospheric environment and the terrestrial environment, the influences of satellite channel propagation characteristics are analyzed respectively.(2) The typical mobile satellite communication channel models:C.Loo model, Suzuki model, Corazza model and Lutz model are studied. The components of the received signal and the applicable channel environment of these models are deeply analyzed. And the corresponding channel model statistical characteristic figures of different transmission environments are given.(3) Considering the influences of atmospheric environment and terrestrial environment, a satellite communication channel Markov model is established. The traditional channel modeling and simulation mainly take into the multipath and shadow fading in the terminal environment account, while the influence of the atmospheric environment is neglected. Due to the shortcomings, the channel fading characteristic in the atmospheric environment is analyzed and the corresponding model is established. Simultaneously, the Markov process describes the dynamic characteristics of the terrestrial environment, and then the satellite communication channel Markov model considering the atmospheric and terrestrial environment is established. By using the improved calculation method of Doppler parameters, the channel model is simulated, which can describe the satellite channel propagation characteristics more accurately.(4) Based on the satellite communication channel Markov model, a satellite communication system simulation model is built by SIMULINK. The bit error rate(BER) performances in the satellite communication system are analyzed respectively for different weather conditions and different shadows. The simulation results verify the rationality of the satellite communication channel Markov model.