为了提高闪电VHF辐射源三维定位系统的探测效率和定位精度,根据其运行原理对其定位误差的可能来源进行了分析,特别是针对GPS时钟的授时原理和高速采集卡工作原理以及观测站位置等可能造成误差的系统原因进行了分析。结果表明,三者误差是造成闪电三维定位结果不准确的主要设备误差。利用闪电VHF辐射源三维定位系统得到的定位结果信息,计算出了其到达观测站的时间,并与实测的到达时间进行了差值分析,拟合出一条偏差直线,得到其误差演变规律,并对该误差进行分析和纠正,得到了较好的结果,使闪电VHF辐射源三维定位系统的探测效率有较大提高,其定位结果更加可靠。
In order to improve the detection efficiency and location accuracy of three-dimension location system of lightning VHF radiation(LLR),basing the principle of LLR,the possible sources of error were analyzed.This study focuses on the error from GPS,A/D card and the position of station which were considered as sources for system error.The time signal from GPS showed a normal distribution which lead to the corresponding error of trigger time.The accumulated error in data was resulted from the unstable crystal oscillator,and it could affect the accuracy of location result greatly.The position error of station was resulted from GPS orientation system,and its correction would be depends on the long-term observation on fixed observation sites.Considering these errors,the difference value,between arriving time detected by receiver and arriving time calculated base on the location results,were fit to a straight line.The evolution rule of error was analyzed and corrected base on this line.And the detection efficiency of LLR was improved greatly and location results of LLR were more credible.