Abstract:
A basic broadband digital interferometer was
developed, which is capable of locating Very High Frequency
(VHF) radiation sources in two spatial dimensions and time.
Three antennas sensed the time series of broadband
electromagnetic (EM) signals and digitized with 4 ns sampling
interval for a duration of several milliseconds. A technique based
on cross-correlations has been implemented for mapping
lightning source locations. A map of the first return stroke (RS)
and the preceding stepped leader was mapped successfully, using
the system with a time resolution of few milliseconds. The result
was compared with the visible events of the ground flash to
validate the system.
