Measurements and Analysis of Propagation Channels in High-Speed Railway Viaducts
Measurements and Analysis of Propagation Channels in High-Speed Railway Viaducts
复制标题
高速铁路高架桥传播通道的测量与分析
DOI：
10.1109/twc.2012.120412.120268
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发表时间：
2013-02-01
影响因子：
10.4
通讯作者：
Molisch, Andreas F.
中科院分区：
文献类型：
--
作者：
He, Ruisi;Zhong, Zhangdui;Molisch, Andreas F.
本文报道了中国所在的郑州至西安高铁沿线在不同的高架桥场景下进行的930 MHz无线传播信道的测量，并在此基础上对小尺度和大尺度信道参数进行了分析和建模。环境可分为四种情况，涵盖不同高度的高架桥和不同的郊区环境。观察到衰落深度、水平交叉率和平均衰落持续时间的小值。Akaike的基于信息准则(AIC)的评估表明，里氏分布最能描述小尺度幅度衰落。对包络自协方差函数的分析表明，相干距离小于10 cm。将Ricean K因子建模为距离的分段线性函数。此外，建立了一个断点路径损耗模型，并用与距离相关的K因子模型相同的断点研究了阴影衰落。铃木分布被发现为复合多径/阴影信道提供了很好的拟合。我们发现，高架桥高度H和周围散射体的数量对小尺度和大尺度的信道参数都有显著影响。这些结果既适用于高速铁路，也适用于高速铁路，对铁路高架通道的建模和铁路无线通信系统的设计具有一定的参考价值。
This paper reports (i) a set of measurements of the wireless propagation channel at 930 MHz, conducted along the "Zhengzhou-Xian" high-speed railway of China in various railway viaduct scenarios, and (ii) an analysis and modeling of the small-scale and large-scale channel parameters based on those measurements. The environment can be categorized into four cases, covering viaducts with different heights and in different suburban environments. Small values of fade depth, level crossing rates, and average fade duration are observed. Akaike's Information Criterion (AIC)-based evaluation indicates that the Ricean distribution is the best to describe small-scale amplitude fading. An analysis of the envelope autocovariance function shows that the coherence distance is less than 10 cm. The Ricean K-factor is modeled as a piecewise-linear function of distance. Moreover, a breakpoint path loss model is developed and shadow fading is investigated using the same break point as for the distance-dependent K-factor model. The Suzuki distribution is found to offer a good fit for the composite multipath/shadowing channels. We find that the viaduct height H, together with the number of surrounding scatterers, significantly affects the small- and large-scale channel parameters. These results are applicable to both normal-speed and high-speed railways, and will be useful in the modeling of railway viaduct channels and the design of railway wireless communication systems.