Design of a High-Power Nanosecond Electromagnetic Pulse Radiation System for Verifying Spaceborne Detectors

Area of Science:

• Electromagnetics
• Atmospheric Physics
• Space Science

Background:

• The Spaceborne Global Lightning Location Network (SGLLN) requires reliable testing signals for its wideband electromagnetic pulse detectors.
• The unpredictable nature of natural lightning hinders the verification of SGLLN's disaster weather detection capabilities.
• A controlled radiation source is essential for calibrating spaceborne lightning detectors.

Purpose of the Study:

• To design and validate a high-power electromagnetic pulse radiation system for testing SGLLN detectors.
• To assess the performance of a novel exponentially TEM feed antenna with integrated pulser.
• To establish an empirical basis for understanding ionospheric effects on radio wave propagation from lightning.

Main Methods:

• Development of a 20 m aperture reflector high-power electromagnetic pulse radiation system.
• Design of an exponentially TEM feed antenna with asymmetric protective loading and pulser integration.
• Far-field experiments using an E-field sensor at 400 m and spaceborne detector simulation at 500 km altitude.

Main Results:

• The radiation system successfully generated nanosecond electromagnetic pulse signals under controlled conditions.
• Far-field measurements showed a peak field strength of 2.2 kV/m with a 1.9 ns rise time and 2.5 ns pulse width.
• Simulated spaceborne detection at 500 km recorded a 10 mV/m signal, exhibiting nonlinear frequency modulation consistent with ionospheric propagation.

Conclusions:

• The developed high-power electromagnetic pulse radiation system provides a stable and robust source for verifying spaceborne lightning detectors.
• The study validates the effectiveness of the designed feed antenna and measurement methodology.
• This research lays the groundwork for future investigations into ionospheric influences on lightning signal characteristics.