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| THEORY OF RADIO WAVE PROPAGATION IN RAILWAY TUNNEL |
| ZHENG Cuoshen,ZHANG Wenmei,ZHANG Yueping,SHENG Jianheng |
| Taiyuan University of Science and Technology |
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Abstract Research on radio wave propagation in tunnels has important application for mobile and personal communication. This paper first briefly reviews radio wave propagation in empty tunnels, and then concentrates on characterizing radio wave propagation in tunnels loaded with trains. For this purpose, an oversized imperfect periodically loaded rectangular waveguide is proposed, and surface impedance approximation is adopted to formulate the problem. The theoretical results show that HEM11 and TSMq.mo modes can propagate. Meanwhile, why TSMq.mo modes can not exist is also proved.The close form propagation constants for those import TSMq.mo modes are obtained. The numerical results for the propagation attenuation of the dominant TSM1.10 are presented. The influence of passengers on propagation is discussed.
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Received: 12 September 1998
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1999, Vol. 16 
