The Influence of Noise Environment upon Voice and Data Transmission in the RF-CBTC System
(0) The RF-CBTC(Radio Frequency-Communication Based Train Control) System is a signaling system in railroad. The communication method of RF-CBTC system is the wireless between the wayside device and on-board device. The wayside device collects its location and speed from each train and transmits the distance from the forwarding train to the speedlimit position to it. The on-board device controlling device controls the speed optimum for the train. In the case of the RFCBTC system used in Korea, transmission frequency is 2.4GHz. It is the range of ISM(Industrial Scientific and Medical equipment) band and transmission of voice and data is performed by the method of CDMA(Code Division Multiple Access). So noises are made in the environment such as AWGN(Additive White Gaussian Noise) and fading. Currently, the SNR(Signal-to-Noise Ratio) is about 20dB, so due to bit errors made by noises, transmission of reliable information to the train is not easy. Also, in the case that two tracks are put to a single direction, it is needed that two trains transmit reliable voice and data to a wayside device. But, by noises, it is not easy that just a train transmits reliable information. In this paper, we estimated the BER(Bit Error Ratio) related to the SNR of voice and data transmission in the environment such as AWGN and fading from the RF-CBTC system using the CDMA method. Also, we supposed the SNR meted on the BER standard for voice and data transmission. By increasing the processing gain that is a ratio of chip transmission to voice and data transmission, we made possible voice and data transmission from maximally two trains to a wayside device, and demonstrated it by using Matlab program.
Bit error ratio Code division multiple access Processing gain Radio frequency-communication based train control Signal to noise ratio
Minseok Kim Sanghyeok Lee Jongwoo Lee
Department of Railroad Electrical & Signaling Engineering, Seoul National University of Technology, 172 Kongneungdoung, Nowon-gu, Seoul, Korea
国际会议
The International Conference on Electrical Engineering 2009(2009 电机工程国际会议)
沈阳
英文
1-7
2009-07-05（万方平台首次上网日期，不代表论文的发表时间）