Title :
Enhancement of rectangular tunnel waveguide model
Author :
Zhang, Y.P. ; Hwang, Y.
Author_Institution :
Dept. of Electr. & Electron. Eng., Hong Kong Univ., Hong Kong
Abstract :
The ray theory is applied to locate the break point to distinguish propagation regions for line-of-sight topographies in rectangular tunnels. It is found that path loss in tunnels differs greatly in the regions prior to and after the break point. Nevertheless at least two waveguide modes are needed to accurately model tunnel natural propagation. In addition, the errors in the formulas to calculate the losses due to roughness and tilt of the tunnel walls are corrected. As a result, the propagation loss prediction of the rectangular tunnel waveguide model is significantly enhanced
Keywords :
electromagnetic wave propagation; losses; rectangular waveguides; waveguide theory; break point; error correction; line-of-sight topographies; path loss; propagation loss prediction; propagation regions; ray theory; rectangular tunnel waveguide model; tunnel natural propagation; wall roughness error; wall tilt error; waveguide modes; Cutoff frequency; Electromagnetic propagation; Electromagnetic waveguides; Frequency estimation; Hollow waveguides; Predictive models; Propagation losses; Radio spectrum management; Rectangular waveguides; Waveguide theory;
Conference_Titel :
Microwave Conference Proceedings, 1997. APMC '97, 1997 Asia-Pacific
Print_ISBN :
962-442-117-X
DOI :
10.1109/APMC.1997.659338
