Electromagnetic environments in roadways of underground coal mines and a novel testing method

The electromagnetic environment of laneways in underground coal mines is an important area for the design of new electronic products, as well as a fundamental space for mine monitoring, surveillance, communications and control systems. An investigation of electromagnetic interference in coal mines is essential for the enhancement of performances of these systems. In this study, a new field method is provided in which radiated emission tests in coal mine laneways have been carried out. We conclude that: 1) the wiring motor vehicles can radiate interference with a bandwidth up to 1 GHz and with an amplitude 10 dBμV/m higher than the background noise; 2) the PHS (Personal Handy phone System) mobile communication system can cause interference 40 dBμV/m higher than the background noise; 3) an interference 25 dBμV/m higher than the background noise can be generated during the communication at a working bandwidth of 48.8 MHz; and 4) power cables, battery vehicles as well as mechanical and electrical dong rooms have little effect on the electromagnetic radiation environment in coal mine tunnels.