Measurement of RF propagation around corners in underground mines and tunnels
Transactions of the Society for Mining, Metallurgy, and Exploration
, 2016, Vol. 340, No. 1, pp. 30-37
Jacksha, R.; Zhou, C.
This paper reports measurement results for radio frequency (RF) propagation around 90° corners in tunnels and underground mines, for vertically, horizontally and longitudinally polarized signals. Measurements of signal power attenuation from a main entry into a crosscut were performed at four frequencies — 455, 915, 2450 and 5800 MHz — that are common to underground radio communication systems. From the measurement data, signal power loss was determined as a function of signal coupling from the main entry into the crosscut. The resultant power loss data show there are many factors that contribute to power attenuation from a main entry into a crosscut, including frequency, antenna polarization and cross-sectional entry dimensions.