Hardware realization of collision avoidance method in VLF-LF frequency bands in mine conditions

The paper proposes a method of measuring the distance between mining equipment and workers in complex conditions of underground mine workings considering the influence of absorbing properties of rocks and the presence of turns and obstacles. The method consists in using a magnetic beacon, operating in VLF-LF frequency range, on the body of mining equipment and receivers on the miner's body to register proximity and notify a person about it. Registration of convergence is carried out by RSSI methods. The authors propose a design solution of magnetic beacon and receiver, which includes amplification stages for signal registration at 30-35 meters. The paper also presents the measurement error of the information parameter under the influence of the ground surface and the tunnel.