The invention discloses an underground life calling
system which comprises a plurality of calling devices, wherein each calling device comprises a power drive module, a composite magnetic doublet antenna, a plurality of
broadband magnetic sensors, a
signal conditioning and collecting module, a calculation and control module and an uninterrupted power supply (UPS) module, the calculation and control module controls the composite magnetic doublet antenna to send out
magnetic field signals through the power drive module, the
broadband magnetic sensors receive the
magnetic field signals sent out by the composite magnetic doublet antenna in other calling devices and the
magnetic field signals are transmitted to the
signal conditioning and collecting module to be through
broadband signal processing, then transmitted to the calculation and control module to be through signal analysis and
processing, and the UPS module is used for supplying power for the broadband magnetic sensors, the
signal conditioning and collecting module, the calculation and control module and the UPS module. A full-duplex communication method is applied in the underground life calling
system, the magnetic field signals are adopted in signal transmission, and impacts of rock stratum environment are avoided. The underground life calling
system is wide in signal cover, safe and reliable, provided with back-up power supplies and capable of guaranteeing continuous calling for help.