Time Delay Correction for the MARCOS Lightning VHF Mapping Array System
Time Delay Correction for the MARCOS Lightning VHF Mapping Array System
复制标题
MARCOS Lightning VHF 测绘阵列系统的时延校正
DOI：
10.1109/temc.2021.3073125
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发表时间：
2021-04
影响因子：
2.1
通讯作者：
Yun Li
中科院分区：
文献类型：
--
作者：
Tao Wang;Li-Hua Shi;Shi Qiu;Zheng Sun;Qi Zhang;Yun Li
在实际应用中，VHF雷电测图系统由于系统制造、安装、场地差异、信道不一致等原因，是不可避免的，并且将影响测向算法的定位精度。本文以一个由7个通道组成的多天线VHF辐射连续观测系统（MARCOS）为例，定量分析了STD与定位误差的关系。阵列呈“L”形，基线为9米。并通过实际测量，采用扫频法得到了其标准偏差。分析结果表明，STD显著降低了定位精度。特别是，低海拔的排放更容易受到STD的影响。为了纠正性病引起的定位误差，我们在算法执行过程中利用MARCOS实际测量的性病来纠正误差。利用无人机和便携式辐射源进行了野外实验，验证了该方法的有效性。对于本文所用的MARCOS系统，无人机实验结果表明，STD引起的误差至少超过2°，在低仰角时误差更大。经过STD补偿后，定位误差减小到1°以内。最后，对一个触发闪电数据进行了STD校正。对STD补偿前后的结果进行了比较和分析。
In practical applications, system time delay (STD) of a VHF lightning mapping system, resulting from system manufacturing, installation, site differences, and signal channel inconsistency etc., is unavoidable and will affect the localization accuracy of the direction finding algorithm. In this article, a multiantenna VHF radiation continuous observation system (MARCOS) consisting of 7 channels is used as an example to make a quantitative analysis for the relationship between STD and localization error. The array is in an “L” shape, with a 9 m baseline. And its STD is obtained through actual measurement, using sweep-frequency method. The analysis results show that STD reduces the localization accuracy significantly. Especially, emissions with lower elevation are more vulnerable to STD. In order to correct localization error caused by STD, we utilize the actual measured STD of MARCOS to correct the error during the implementation of the algorithm. Field experiments are designed to verify the effectiveness of this correction method, with an unmanned aerial vehicle (UAV) and a portable radiation source. For MARCOS used in this article, the UAV experimental results show that the error caused by STD exceeds at least 2°, and even worse for the low elevation. However, after the STD is compensated, the localization error is alleviated within 1°. Finally, STD correction is applied to a triggered lightning data. Comparisons and analyses of the results are presented before and after STD compensation.