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Propagation of UHF radio waves in trapezoidal tunnels

✍ Scribed by G. X. Zheng; J. H. Sheng; Y. P. Zhang

Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
88 KB
Volume
20
Category
Article
ISSN
0895-2477

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✦ Synopsis

Measurements of the propagation of UHF radio wa¨es in two trapezoidal tunnels are reported. Values of propagation loss in dBr100 m are gi¨en. It is found that the propagation attenuates at least 900 MHz. In addition, a portable FM radio system operating at 900 MHz is tested in one tunnel. It achie¨es a highly intelligible communication range of 230 m.

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