A remote sensor for the three components of transient electric fields

Abstract

An active device for measuring the three orthogonal components of a wideband (3 Hz to 4 MHz) transient electric field is described. The system design is specifically tailored to detect the electric fields from lightning occurring at distances from less that 1 km to over 100 km. Each electric field component is sensed on one of three isolated sections of a single metallic sphere that itself is electrically isolated from its surroundings. Electronics within the sphere detect and process signals proportional to the charges induced by the electric fields on the isolated sections of the sphere. The signals are passed to a remote recording device via analog fiber optics links. Also contained within the sphere are controls both to change gain settings and to apply internal calibrations on command from a remote VHF transmitter.<>