Lightning VHF Radiation Mapping Method for an Irregular Short‐Baseline Array

Abstract

Abstract Lightning very high frequency interferometry is a crucial tool for studying the development of lightning leaders within thunderclouds, and the conventional antenna array is composed of two coplanar orthogonal baselines. In this study, we develop two new location methods for an irregular array based on the optimization algorithm, using all baselines in the calculation. Besides, we have analyzed the effects of two kinds of time uncertainty on the location result and provided a calibration method. The first type—the systematic time drift of antennas—can induce an offset on the location result, leading to a worse accuracy. We can calibrate the time drift of each antenna efficiently during the experiment. The second type—the waveform distortion between different antennas—can introduce the noise on time, leading to worse precision. The location precision improves when more baselines are used, whether they are independent or redundant. Our result shows that the non‐coplanar configuration can significantly improve the elevation uncertainty near the horizon and the azimuth uncertainty near the zenith after considering the angular uncertainty's theoretical distribution.

Keywords

• interferometry
• lightning location
• non‐coplanar array