资源环境科技发展态势分析平台

Based on fast electric field waveforms of the Low-frequency E-field Detection Array (LFEDA), we introduce the time reversal technique into lightning three-dimensional location for the first time and propose a new algorithm for the three-dimensional location of lightning low-frequency discharges. Without using complex filtering algorithms to remove higher-frequency component, this method obtains similar results to the newly reported LFEDA refinement algorithm. The new algorithm can obtain finer, more continuous, and richer positioning results with a minimum of four stations, 5-dB signal-to-noise ratio, and 500-ns time error compared with the low-frequency signal time of arrival three-dimensional positioning method. These results indicate that the new algorithm has the advantages of low requirements on the number of stations, certain anti-interference ability, and low requirements on time accuracy. The standard deviations in the X and Y directions for return strokes of triggered lightning flashes are both approximately 90 m.

Plain Language Summary During the last 20 years, besides the location of return stroke, finer and more accurate positioning of total lightning based on lightning low-frequency discharge signals can be achieved by using the time of arrival method. The Chinese Academy of Meteorological Sciences developed a lightning Low-frequency E-field Detection Array (LFEDA), consisting of ten substations in Conghua, Guangzhou, since 2014, which is capable of determining the three-dimensional locations of lightning discharge events. With the application of empirical mode decomposition algorithm in the past research of LFEDA, the fine structure of lightning channel can be obtained. This paper proposes a new lightning low-frequency discharge three-dimensional location algorithm based on the multistation waveform data of the LFEDA system. This is the first time that the time reversal method has been applied to total lightning three-dimensional location. This method can obtain accurate lightning three-dimensional location results without using a complex filtering algorithm. Compared with the time of arrival method, the new algorithm not only can yield positioning results similar to those of the fine positioning algorithm (Fan et al., 2018, ) but also has the advantages of low requirements on the number of stations, certain anti-interference ability, and low requirements on time accuracy.