超短基线电磁脉冲阵在电磁辐射源测向中的应用

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.