一种适用于双卫星系统窄带LMS信道的状态模型

针对单卫星系统业务有效性低和状态模型使用场景有限的问题，根据全球导航卫星系统实测数据提取的模型参数提出一种适用于更多场景的陆地移动卫星信道状态模型。基于一阶马尔可夫链和半马尔可夫链实现双卫星的联合状态序列，研究各种仰角组合和方位角分离下状态序列的相关系数、状态概率及状态持续时间的统计特性。仿真结果表明，与实测值比较，对数正态拟合的半马尔可夫模型能更精确、有效地描述双卫星传播信道的状态，且在不同信道环境的各种星座下具有更好的适用性，可用于多星信道模型的建立和系统性能分析。

State modeling of the narrowband LMS channel suitable for dual-satellite systems

Considering the low service availability and limited usage scenarios of state modeling for the single-satellite system, the state modeling of the Land Mobile Satellite (LMS) channel, based on the model parameters extracted from the Global Navigation Satellite Systems(GNSS) measurement data, is analyzed for much more scenarios. A joint generation of the states sequence for the dual-satellite is presented by the first-order Markov chain and semi-Markov chain. Various elevation combinations and azimuth separations in terms of correlation coefficients, state probabilities, and state duration statistics are analyzed. Simulation results show that the semi-Markov model with lognormal-fit can describe the state modeling of the dual-satellite propagation channel more accurately and effectively compared with the measurements. It has better applicability for various constellations in different channel environments, and can be used in modeling of the multi-satellite channel and system performance analysis.