## 2 The Method Involving the Lightning Location and Experimentation  
During the occurrence of lightning, electromagnetic waves are emitted outward, primarily within the frequency range of 1 Hz to 300 MHz [41]. As illustrated in Figure 1, ground-based lightning detection networks utilize captured electromagnetic wave signals to compute crucial parameters, such as the time of arrival (TOA) and directional finder (DF), based on the unique characteristics of these radiation signals [42; 43]. The DF method, although requiring fewer observation stations, tends to exhibit relatively larger measurement errors. Conversely, the TOA method offers high positioning accuracy, but necessitates a substantial number of observation stations. Scholars have employed magnetic field sensors and audio sensors for synchronous measurements, aiming to determine the distance of lightning strikes, based on the significant disparities between acoustic and magnetic propagation speeds [44]. Ground-based lightning detection technology has undergone extensive exploration and application over an extended period [2; 45; 46]. Currently, large-scale ground-based lightning detection networks include the National Lightning Detection Network (NLDN) in the United States, the World Wide Lightning Location Network (WWLLN), the Global Lightning Detection System (GLD360), and the Advanced Direction Finding and Time Difference (ADTD) established by China's Meteorological Administration, and the State  
Figure 1: The lightning location method, based on the time of arrival (TOA) and directional finder (DF) [43]. Grid Lightning Network (SGLNET), constructed by the State Grid Corporation of China. Taking SGLNET as an example, it presents a fully automated and precision-oriented lightning monitoring system, capable of capturing crucial lightning parameters, including the time, position, peak current, polarity, and numerous others. Since the early 1990s, the State Grid began to establish a provincial lightning monitoring system in China. By the end of 2015, SGLNET had built 45 central stations and 776 detection stations, achieving full coverage in the whole country (as shown in Figure 2). The technical level and scale of the SGLNET station network has reached a leading level internationally [47]. The datasets on the lightning location contain information such as the time, longitude, latitude, peak current, and polarity of the CG strokes [7]. Scholars have compared the results from artificially triggered lightning experiments and the Guangzhou high-tower observation station with the location of SGLNET, indicating that the location error and detection efficiency of SGLNET is 710 m and 94%, respectively [48]. As a highly controllable lightning measurement method, rocket-triggered lightning has been used to study the physical processes and discharging mechanism of natural lightning flashes [49; 50; 51; 52; 53; 54; 55; 56; 57; 58]. Figure 3 provides a sketch of the experiment setup for the triggered lightning experiment related to the Field Experiment Base on Lightning Sciences, by the China Meteorological Administration (CMA-FEBLS), in the summer of 2019. The whole experimental field consisted of a rocket launching point, control room, close observation site, and far observation site. The distance from the close site and far site to the rocket launching site was 79 m and 1.9 km, respectively. Under vigorous thunderstorm conditions when the surface E-field reaches a certain threshold (e.g., 4.0 kV/m), the operator turned on the power switch of the ignition box in advance, and when the conditions were suitable, the wired rocket was launched into the bottom of the thundercloud. A high-speed video camera, slow and fast antenna, surface E-field, and other equipment were installed at the trigger site, and the main site was able to be used for simultaneous observation and study of the lightning discharge process by optical, electrical, and magnetic means [52]. The  
Figure 2: Distribution of detection stations in SGLNET, constructed by the State Grid Corporation of China [47].