基于TDOA的超长基线闪电定位算法

Source Locating Algorithm for Ultra-long Baseline Lightning Detection System Based on TDOA

为补充中国对超长基线闪电探测系统研究的不足,开发了1套超长基线闪电定位算法,该算法基于群时延计算到达时差(TDOA),并在WGS-84基准椭球面上完成定位。对于闪电回击点的确定,采用高斯牛顿迭代方法,与常规的网格搜索方法进行了理论模型算例对比,说明该算法具有较高的运算效率并可以提高阵外闪电的定位精度达百公里量级。将该算法应用于超长基线实测数据的定位,并与中国电网江苏地区的闪电定位结果进行匹配,得到2者平均距离差为11.48 km,对于超长基线定位系统定位精度较高,证明开发的超长基线闪电定位算法在实际应用中稳定可靠。

For insufficient research on ultra-long baseline lightning detection system in China, we propose a source locating algorithm based on time difference of arrival(TDOA), which is optimized by time of group arrival method and based on WGS-84 ellipsoidal system. The Gauss-Newton method is applied to search for the location of the return stroke, which shows higher computing efficiency and can improve the out-of-array positioning accuracy by hundreds of kilometers, compared with regular grid search method in synthetic example tests. Contrasted with the reference location data of the State Grid in Jiangsu Province, the locating result by our algorithm has a high accuracy that the mean distance error of matched events is 11.48 km, in the light of such a long baseline. The result shows that the locating algorithm is reliable in practical applications.