Modeling of the Division Point of Different Propagation Mechanisms in the Near-Region Within Arched Tunnels

An accurate characterization of the near-region propagation of radio waves inside tunnels is of practical importance for the design and planning of advanced communication systems. However, there has been no consensus yet on the propagation mechanism in this region. Some authors claim that the propagation mechanism follows the free space model, others intend to interpret it by the multi-mode waveguide model. This paper clarifies the situation in the near-region of arched tunnels by analytical modeling of the division point between the two propagation mechanisms. The procedure is based on the combination of the propagation theory and the three-dimensional solid geometry. Three groups of measurements are employed to verify the model in different tunnels at different frequencies. Furthermore, simplified models for the division point in five specific application situations are derived to facilitate the use of the model. The results in this paper could help to deepen the insight into the propagation mechanism within tunnel environments.

[1]  Bo Ai,et al.  Research of propagation characteristics of break point: near zone and far zone under operational subway condition , 2010, IWCMC.

[2]  Y. Hwang,et al.  Enhancement of rectangular tunnel waveguide model , 1997, Proceedings of 1997 Asia-Pacific Microwave Conference.

[3]  Ernst Bonek,et al.  Radio coverage of road tunnels at 900 and 1800 MHz by discrete antennas , 1994, 5th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Wireless Networks - Catching the Mobile Future..

[4]  M. Liénard,et al.  On the Possibility of Interpreting Field Variations and Polarization in Arched Tunnels Using a Model for Propagation in Rectangular or Circular Tunnels , 2008, IEEE Transactions on Antennas and Propagation.

[5]  J. Romeu,et al.  Break point analysis and modelling in subway tunnels , 2009, 2009 3rd European Conference on Antennas and Propagation.

[6]  Guoxin Zheng,et al.  Radio propagation at 900 MHz in underground coal mines , 2001 .

[7]  Y. P. Zhang,et al.  Characterization of UHF radio propagation channels in tunnel environments for microcellular and personal communications , 1998 .

[8]  Simon R. Saunders,et al.  Antennas and Propagation for Wireless Communication Systems , 1999 .

[9]  Cesar Briso-Rodríguez,et al.  Measurements and Modeling of Distributed Antenna Systems in Railway Tunnels , 2007, IEEE Transactions on Vehicular Technology.

[10]  Bo Ai,et al.  Propagation Mechanism Analysis Before the Break Point Inside Tunnels , 2011, 2011 IEEE Vehicular Technology Conference (VTC Fall).

[11]  Thomas Haug,et al.  The GSM System for Mobile Communications , 1992 .

[12]  Gorazd Kandus,et al.  Four-slope channel model for path loss prediction in tunnels at 400 MHz , 2010 .

[13]  Martine Lienard,et al.  Theoretical and experimental approach of the propagation of high frequency waves in road tunnels , 1994 .

[14]  Yue Ping Zhang.  Novel model for propagation loss prediction in tunnels , 2003, IEEE Trans. Veh. Technol..