Abstract
Nowadays, in urban rail transit systems, train wayside communication system uses Wireless Local Area Network (WLAN) as wireless technologies to achieve safety-related information exchange between trains and wayside equipment. However, according to the high speed mobility of trains and the limitations of frequency band, WLAN is unable to meet the demands of future intracity and intercity rail transit. And although the Time Division-Long Term Evolution (TD-LTE) technology has high performance compared with WLAN, only 20 MHz bandwidth can be used at most. Moreover, in high-speed scenario over 300 km/h, TD-LTE can hardly meet the future requirement as well. The equipment based on Enhanced Ultra High Throughput (EUHT) technology can achieve a better performance in high-speed scenario compared with WLAN and TD-LTE. Furthermore, it allows using the frequency resource flexibly based on 5.8 GHz, such as 20 MHz, 40 MHz, and 80 MHz. In this paper, we set up an EUHT wireless communication system for urban rail transit in high-speed scenario integrated all the traffics of it. An outdoor testing environment in Beijing-Tianjin High-speed Railway is set up to measure the performance of integrated EUHT wireless communication system based on urban rail transit. The communication delay, handoff latency, and throughput of this system are analyzed. Extensive testing results show that the Quality of Service (QoS) of the designed integrated EUHT wireless communication system satisfies the requirements of urban rail transit system in high-speed scenario. Moreover, compared with testing results of TD-LTE which we got before, the maximum handoff latency of safety-critical traffics can be decreased from 225 ms to 150 ms. The performance of throughput-critical traffics can achieve 2-way 2 Mbps CCTV and 1-way 8 Mbps PIS which are much better than 2-way 1 Mbps CCTV and 1-way 2 Mbps PIS in TD-LTE.
Highlights
With the rapid development of the city size, the urban rail transit becomes the main trip mode of human beings which could provide safe, punctual passenger services within urban areas and intercity
We firstly study the integrated Enhanced Ultra High Throughput (EUHT) wireless communication system based on urban rail transit in high-speed scenario, which works in the 5.8 GHz
There are EUHT Access Unit (EAU) used for onboard network access and EUHT Service Unit (ESU) used for analyzing and processing the data received by EAU, and four PCs connected with ESU are the analog on-board servers for communicationbased train control (CBTC), train state monitor, passenger information systems (PIS), circuit television (CCTV), and emergency text, respectively
Summary
With the rapid development of the city size, the urban rail transit becomes the main trip mode of human beings which could provide safe, punctual passenger services within urban areas and intercity. Through the optimization design of the synchronization sequence, the receiver can achieve a reliable estimate of the large frequency deviation at low cost, greatly reducing the requirement of crystal performance to +/−20 ppm Due to these advantages, EUHT has a better performance than existing WLAN and TD-LTE technology in high-speed scenario up to 500 km/h. An integrated EUHT wireless communication system based on urban rail transit in high-speed scenario is designed, which works in the 5.8 GHz and includes all the traffics in CBTC systems. The test results show that the QoS performance of integrated EUHT wireless communication system based on urban rail transit satisfies the requirements of safety-critical traffics and throughput-critical traffics in high-speed scenario well, and has greatly performance improvement comparing with TD-LTE system.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
