Radio-wave Propagation in Tunnel Structures at ISM Band: A Preliminary Study

This paper presents a preliminary study of radiowave propagation along tunnel & tunnel-like structures in the industrial, scientific and medical radio band (ISM band). These structures often have a rich multipath environment due to their waveguiding effect In this study, the existence of radio-wave guiding effect along tunnel-like structures was investigated with the measured power delay profiles (PDPs). The experimental results are validated with the simulation results using a ray-tracing simulator. Additionally, simulation study is further performed on different tunnel structures to analyze the variation of radio-wave propagation mechanism. The results of this study are useful to get a better understanding of complex waveguiding effect in a tunnel environment.