中文摘要：

卫星网络技术以其独特优势成为研究热点,本文以卫星地面链路作为研究对象,对星地链路进行深入分析,细致刻画链路特性,在此基础上归纳星地链路延时的构成因素,从固定延时、可变延时和突发延时3个方面考虑,建立了时变的星地链路延时模型.详细分析了链路中影响误码率的各种损耗和噪声源,建立了基于卫星链路功率预算的链路误码率模型,基于给定的星地链路场景对延时和误码率模型进行了对比验证.结果表明本文提出的延时模型能够更细腻地刻画星地链路的延时,更精细地反映链路延时的变化特性;误码率模型考虑的因素更加全面,能够更真实地刻画星地链路的误码特性.两个模型可以作为卫星链路分析和设计的一个有效辅工具.

英文摘要：

By it＇s special superiority, satellite network technology has become a hot research field; this paper takes satellite-ground link as research object; analyzes the satellite-ground link in depth, characterizes the feather of the link in detail. Then presents the delay components analysis of satellite-ground link from fixed delay, variable delay and burst delay, builds a time-varied satellite-ground link delay model. Based on the detailed analysis of the many factors that cause attenuation and noise to the radio wave signals, this article gives a bit error model of satellite-ground link on link power budget analysis. In the following, the two models are verified with the data generated by STK software, the results represent good accommodation. In the delay model, there is a fine-grained characterization and thus is able to reflect the delay diversification of the link better. With comprehensive factors taken into account when realizing the bit error rate model, the final model presents a true reflection of the real case. The two models play as an active supplementation in satellite-ground link design and analysis.