日批在线视频_内射毛片内射国产夫妻_亚洲三级小视频_在线观看亚洲大片短视频_女性向h片资源在线观看_亚洲最大网

By Cheng Xiusheng & Chen Longquan, Research Team on “Roadmap for the Development of China’s High-speed Railway IC Technology”, Information Center, DRC

Research Report, Special Issues, No 71, 2015 (Total NO. 1474) 2015-12-31

Abstract: Security, stability and high rate are the objective requirements of the high-speed wireless communication. Existing GSM-R system cannot provide a larger bandwidth to carry the passengers’ access requirements. What’s more, with the increasing speed-up of high-speed railway and the extensive use of broadband Internet services, conflicts between existing GSM-R system and passengers’ access requirements have become intensified. Whereas due to the issues of network problems along the base station construction and section distribution, public network is difficult to guarantee the stable quality of access. Neither public network nor private network can independently reach the access requirement of modern high-speed railway. The solution of public network is to allocate a large number of base stations, however, owing to short-term concentration of railway communication service, base stations are vacant for a long time with inadequate usage, which makes public network become private network. While a large part of the bandwidth of the GSM-R system needs to be set aside to ensure the normal operation of railway, so its actual availability rate is only one hundred KB order of magnitude. In addition, railway private network is evolving into public network. Therefore, public network used as private network and private network used as public network are two main solutions of high-speed wireless communication in the new era.

Key words: public network used as private network, private network used as public network, high-speed railway wireless communication of next generation