Natural wave propagation in mine environments

Theoretical and experimental aspects of the natural propagation of high-fre quency waves in mines are presented. A narrow-band and a wide-band analysis have been carried out to determine the most important characteristics of t he channel such as the longitudinal attenuation, the coherence bandwidth, a nd the delay spread of the impulse response in the various areas of an unde rground mine. The basic principle of a localization of a mobile has also be en checked by determining the direction of arrival of the waves.