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UHF Propagation in Caves and Subterranean Galleries

An experimental study is described on the natural propagation of UHF band radio waves in straight subterranean galleries. An extensive measurement project took place in five underground localities and, based on the experimental data, an empirical model of radio wave transmission was derived. The model was calibrated according to the measurement data and compared with the theoretical waveguide approach to propagation prediction. The presented results can be used for the practical planning of wireless communications in speleology applications and as an experimental basis for further theoretical works