Experimental study of single-station lightning locating technique

An improved approach for locating close lightning strokes based on single-station observation was proposed and practiced. In the approach, a lightning stroke was modelled with an electrical dipole carrying current components in VLF/LF frequency bands, as wavelengths in these frequency bands were much longer than the effective length of the channel of a lightning stroke. For a close lightning stroke, the ratio of the spectra of its vertical electrical field and horizontal magnetic field at ground is theoretically a function of the frequency and the distance to the stroke. The distance of the stroke can then be obtained by fitting the theoretical function with the observed data. The approach was examined by applying it to broadband VLF/LF electrical and magnetic field waveforms observed simultaneously at one station for several strokes in a distance range of 5 to 80 km. In addition, a prototypal single-station lightning location system, which can be analogized to a modified VLF/LF broadband cross-loop magnetic direction finder adding with a lightning distance determining approach, was built up and tested in field. Comparisons with local lightning location network showed that the single-station system performed well.