Observations on Schumann resonance in industrial area
Schumann resonance (SR) can be used to monitor global temperature variations, to explore new geophysics phenomena in the low ionosphere and for short-term earthquake prediction, etc. However, it cannot be observed in the industrial area by the traditional monitoring method. Yampolski et al. observed the first three spectrum peaks of SR cross-modulated on the high frequency waves. The engineering work has been researched in this Letter. By demodulating the short-wave time service signal BPM on 10 MHz, the first four peaks of Schumann resonance were obtained with only a simple cross-dipole antenna. Also the cross-modulation index was measured up to 1×10−4 compared to 3.5×10−4 by academic calculation. The feasibility of the engineering is validated. The other possible method to observe SR is discussed.