Design of Segmented Ultra-Wideband TEM Horn Antenna for Calibration of Wideband Electromagnetic Pulse Sensors

Wideband electromagnetic pulse detection is a crucial method for lightning disaster monitoring. However, the random nature of lightning events presents challenges in fulfilling real-time calibration requirements for electromagnetic pulse sensors. This paper introduces a segmented ultra-wideband TEM horn antenna tailored for portable calibration experiments in electromagnetic pulse detection systems. The radiating plates feature a four-section polygonal design, and an end-loaded metal plate is integrated to reduce reflection signal interference. Rigorous simulation analyses were performed on three key factors impacting antenna radiation performance: aperture impedance, tapering profile, and end loading configuration. Experimental results show that the designed antenna achieves a peak field strength of 48.9 V/m at a 10 m distance, with a rise time of 0.87 ns and a full width at half maximum of 1.75 ns. The operating frequency ranges from 48 MHz to 150 MHz, with main lobe beamwidths of 43° and 83° in the <i>E</i>-plane and <i>H</i>-plane radiation patterns, respectively. These parameters meet the technical requirements for electromagnetic pulse sensor calibration experiments.