A radio communications network for voice and data in underground mines

A 900 MHz radio communications network, designed specifically for underground mines, is described. It has been conceived as a modern, microcellular approach to the provision of quality and reliable mine-wide integrated communications for multiple channels of two-way voice, data, and compressed digital video signals. The network backbone is a cascade of base stations with switching capability to enhance network reliability. The 512 kb/s common air interface (CAI) has been formulated to flexibly cater for the data and voice traffic likely to be encountered in underground mining. Computer simulated results on of the CAI under integrated voice and data traffic conditions are also presented.