| 摘要 |
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. Preprocessing circuitry upon command from a programmable microprocessor A to D converts the integrated and sampled field components where they are stored as digital data in FIFO memories. In response to control signals from the control circuitry the microprocessor transfers the digital data from the FIFO memories to its own memory whereupon it determines the azimuth and elevation angles to the lightning activity based on the sampled field data and determines the range based on the ratio of the magnetic to electric field components using the integrated values of the magnetic and electric fields. The angle and range information is transmitted to a display processor and display where it can be displayed in a variety of formats. Where the apparatus is mounted in an aircraft, the speed of the aircraft and changes in heading are factors into the determination and display of the angles and range.
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