Ka Band Deep Space Communication Channel Modeling Based On The Exploration Of Mars

Mars probe collected data in the form of radio waves and sent them back to Earth. When radio waves are transferred from distant outside space to the surface of ground, it experienced the complex environment of the space of deep space and near-earth space. Various factors affect radio waves, and the interference mechanism of these factors lead to different impact effect.According to characteristics of Mars probe to relay satellite link and the relay satellite to the earth station link, we segmented and integrated the study of the Ka-band deep-space communication channel. Mars probe to relay satellite link and the relay satellite to the earth station link. The thesis studies the satellite communication channel and deep space channel transmission characteristics, and discuss the various factors that affect radio wave propagation in deep space communication process, and suggested the statistic and simulating channel model by developing the propagation characteristics and the measured results of the channel.Firstly the thesis discussed near-ground link factors due to weather and multi-path. We find that the weather and multi-path effects on the channel are independent, and calculate the bound of BER for BPSK modulation. In addition, we set up the complete channel of satellite and deep space communication by way of combining deep space long delay and disruption. On the study of system performance, the fading effects on transmitted signal are simulated and the amounts of performance degradation are different depending on different weather conditions. Signal phase fading has a relatively small effect as compared with signal envelope fading. Finally through the analysis and study of Ka-band deep-space communication link outage probability, we find that cooperative diversity can improve system performance.