中文摘要：

随着高速列车与地面间通信需求的提高,现有窄带铁路列控系统（GSM-R）将向未来基于LTE的宽带铁路通信系统（LTE-R）平滑演进.无线信道测量与参数提取是设计新一代高铁通信系统的前提.莱斯K因子是表征信道衰落程度的重要参数,因此研究高铁宽带无线信道的K因子特征具有重要意义.本文基于郑西（郑州—西安）高铁高架桥场景信道测量数据,分别提取窄带和宽带K因子.分析窄带K因子的时频变化特性,建立基于收发端相对距离的窄带K因子统计模型.探索宽带K因子随信道带宽变化的规律,给出基于信道带宽的宽带K因子统计模型.最后,讨论了不同多径时延的K因子特征.

英文摘要：

Owing to higher and higher requirements for communication between the high-speed train and the ground,the existing narrow-band train control system（GSM-R）has been commonly recommended to be evolved smoothly into a broadband railway communication system based on long term evolution （LTE-R）.Wireless channel measurements and parameter extraction are the prerequisites for designing of the novel wireless communication system.The Ricean K-factor is a fundamental parameter of the wireless channel,which directly reflects the fading severity and communication quality.Consequently,deep research on such a characteristic of railway wireless channels is of utmost importance.In this paper,narrow-band and broadband K-factor were extracted respectively from channel data measured in the viaduct scenario of the Zhengzhou-Xi＇an （ZX） High-speed Railway.For the narrow-band K-factor,the characteristics of time and frequency variability were analyzed and a distance-dependent statistical model was built.For the broadband K-factor,the law of its changing with bandwidth was explored and a bandwidth-dependent statistical model was built.Finally,the K-factor variation with different delay bins was discussed.