Patent ID: 6215294
Filing Date: 2001-04-10
Classification: G01R

Abstract:
An apparatus for determining the location of lightning strokes, each lightning stroke generating electric (E) and magnetic (H) field components said apparatus comprising:receiving means for receiving separately the electric (E) and magnetic (H) field components of a lightning stroke and for generating electrical signals associated with said E and H field components, said electrical signals being characterized by an initial rise time and a plurality of subsequent sub-pulse rise times;means coupled to said receiving means for determining the direction to said lightning strike relative to said apparatus by operating upon said electrical signals associated with both said E and H field components; and;means coupled to said receiving means for determining the distance to said lightning stroke from said apparatus by operating upon said E and H field components, said distance determining means comprising:means for measuring, at a first frequency, a first magnitude of a received H field component of said lightning stroke; andmeans for measuring rise time to peak of a received E field component of said lightning stroke; andmeans for determining the distance to said lightning stroke as, an inverse function of both said first magnitude and rise time to peak of said E field component; wherein the functional relationship of the distance to said frequency and time to peak comprises:R=13250/(1.5*H+0.5*RISETIME*RISETIME)Wherein H is the magnitude of said first frequency, RISETIME is the time to peak of said first E field component and R is the range to the lightning flash.