This paper deals with several aspects relative to the Multiple-Input Multiple-Output (MIMO) propagation channel. Measurement campaigns, made in a real gold mine at 2.4 GHz under line-of-sight (LOS) and non-line-of-sight (NLOS) scenarios, have been analyzed to obtain the relevant statistical parameters of the channel. It was shown that the MIMO exploit the multipath propagation in rich scattering environment to increase the capacity. Hence, the channel is characterized in terms of K-factor, path loss, shadowing, and capacity. Results show a propagation behavior that is specific for these underground environments with rough surfaces.
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