摘要
为提高电磁辐射源的定位精度,该文提出一种利用光纤方式同步的超短基线电磁探测阵列(CASMA)。该阵列包括5个电磁探测站和1个控制中心,阵元间距约为1 km(基线长度与波长的比值约为0.1),同步精度可达10 ns。CASMA用来测量20～70 kHz长波发射电台的垂直电场信号,并利用低频电磁干涉成像算法计算发射电台的方位角。通过实验对比可以发现,估计的发射台方位角与真实发射台方位角之间的误差小于0.2°,远远优于传统的波达角估计方法。因此,CASMA对电磁辐射源具有很高的测向精度。根据实验结果,在2500 km范围内,若两CASMA电磁探测阵对电磁辐射源进行交汇定位,定位精度预期可达0.5%·R(R为探测距离)。
To improve the location resolution of electromagnetic radiation source,a ultra-short baseline network CASMA(Mini-Array by Chinese Academy of Sciences)is proposed for detection,utilizing optical fiber for timing.CASMA contains 5 electromagnetic detection stations and a control unit.The distance between each pair of stations is about 1 km,meaning that the length of baseline to the wavelength is about 0.1.The timing accuracy is about 10 ns.CASMA is applied to record the vertical electric field emitting by radio transmitters.CASMA utilizes interferometric imaging algorithm to calculate the transmitters’azimuth.By experiment,the calculated azimuths approach the expected azimuths with deviations are less than 0.2°,showing many advantages over traditional systems or methods.Consequently,CASMA has accuracy direction finding resolution for electromagnetic radiation source.According to the results,the location accuracy may be expected to be 0.5%·R in a 2500 km scope where R is the distance between the electromagnetic radiation source and CASMA using two sets of CASMA for intersection positioning.
作者
渠晓东
孙阳
陈冲
石俊龙
许鑫
李巨涛
朱万华
方广有
QU Xiaodong;SUN Yang;CHEN Chong;SHI Junlong;XU Xin;LI Jutao;ZHU Wanhua;FANG Guangyou(Key Laboratory of Electromagnetic Radiation and Sensing Technology,Chinese Academy of Sciences,Beijing 100190,China;Institute of Electronics,Chinese Academy of Sciences,Beijing 100190,China;96669 Troop of the PLA,Beijing 102208,China)
出处
《电子与信息学报》
EI
CSCD
北大核心
2019年第4期830-836,共7页
Journal of Electronics & Information Technology
关键词
干涉成像
甚低频
超短基线
Interferometric imaging
Very low frequency
Super-short baseline
