Abstract: Electric (E) and magnetic (H) field components of a lightning stroke are separately received in order to determine and display the location of regions of recently occuring lightning activity. Direction is determined by operating upon electrical signals associated with both the E and H field components. Range is determined by measuring the magnitude of the H field at two different frequencies. The range is then computed as a function of the ratio of the magnitude of the H field at a first frequency to the magnitude of the H field at a second frequency.

Abstract: An apparatus and method of detecting, tracking and displaying lightning activity is disclosed. A lightning stroke has associated therewith electric and magnetic field components characterized by maximum rise times and minimum power levels. The field signals comprise a plurality of sub pulses also. An electric field antenna and a pair of magnetic field antennas are disposed to receive the field components associated with lightning activity. Control circuitry cooperating with rise time and threshold measuring which operates on the field signals received by the antennas generates control signals including integration and sampling control signals for integrating the electric and magnetic field signals over a predetermined time interval (preferable one hundred microseconds) and for sampling and holding the field signals at each of the sub pulse peaks.

Abstract: An apparatus and method of detecting, tracking and displaying lightning activity is disclosed. A lightning stroke has associated therewith electric and magnetic field components characterized by maximum rise times and minimum power levels. The field signals comprise a plurality of sub pulses also. An electric field antenna and a pair of magnetic field antennas are disposed to receive the field components associated with lightning activity. Control circuitry cooperating with rise time and threshold measuring which operates on the field signals received by the antennas generates control signals including integration and sampling control signals for integrating the electric and magnetic field signals over a predetermined time interval (preferable one hundred microseconds) and for sampling and holding the field signals at each of the sub pulse peaks.

Abstract: A system for adaptively determining the direction of arrival (DOA) of a larly polarized RF signal. Three antennae are positioned at fixed distances from one another in a right triangle configuration to receive the RF signal. The antennae are alternatingly switched into two orthogonally aligned pairs and each pair exhibits an antenna pattern null which is adaptively steered toward the RF signal by a computer program operatively connected to a variable phase shifter which selectively alters the phase of the received signal. An algorithm within the program calculates the direction of arrival of the signal relative to a selected one of the antenna pair axes.