高铁山地场景下的车地无线信道建模

高铁列车经过山地场景时由于散射体分布不均匀使得无线信号呈现明显的衰落特性。针对这一现象,提出一种在高速运行状态下列车与基站之间的车地无线信道建模方法。在列车相对基站的不同位置区间内,采用马尔科夫链模拟平均接收信噪比的状态变化,根据高铁山地场景中的路径损耗模型计算得到平均接收信噪比阈值、量化值及信道状态转移矩阵,从而建立有限状态马尔科夫链(FSMC)信道模型。仿真结果表明,与通过均匀与非均匀划分列车位置范围建立的信道模型相比,FSMC模型均方误差最小,可有效评估列车与基站之间的通信质量。

Train-Ground Wireless Channel Modeling for High-Speed Railway in Mountain Scene

When a train of high-speed railway passes through mountain scenes,the wireless signals show obvious fading characteristics due to the uneven distribution of scatterers.To address the problem,this paper proposes a wireless channel modeling method between the base station and the train running at a high speed.In different ranges of the train’s position relative to the base station,Markov chain is used to simulate the state changes of average received Signal to Noise Ratio(SNR).According to the path loss model of high-speed railway in mountainous scenario,the average SNR threshold,quantified value and the channel state transition matrix are calculated to establish the Finite State Markov Chain(FSMC)channel model.Simulation results show that the Mean Square Error(MSE)of the FSMC model proposed in this paper is the smallest compared with that of the channel model established by evenly and unevenly dividing the range of the train’s position,which demonstrates that the proposed model can effectively evaluate the quality of communication between the train and the base station.