中文摘要：

为高速列车旅客提供稳定的宽带无线接入网络服务是需要解决的问题。本文首先比较国内外现有的几种高速铁路宽带无线接人方案，指出它们各自的优缺点；然后阐述在高速铁路特殊场景下公众宽带通信接入网络建设面临的主要难题，包括多普勒频移、多径效应、穿透损耗和快速切换等；最后探讨认知无线电、压缩感知、OFDM、MIMO和RoF等技术在高速铁路公众宽带通信接入网络上应用的可行性。

英文摘要：

How to provide stable broadband multimedia services for passengers on high-speed trains remains one of the urgent problems to be solved currently. In this paper, several broadband wireless access networks ap- plied in high-speed railways at home and abroad are analyzed and their advantages and disadvantages are ex- plained. The main problems brought about by the specificities of high-speed railways is installation of the public broadband wireless access network are discussed, such as the doppler frequency shift, multipath effect, penetration loss and fast handover. Applications of new technologies are introduced, such as the cognitive radio, composed sensing, OFDM, MIMO and RoF.