电磁点源辐射线法用于复杂二维干涉仪测向研究

Research on Sophisticated 2-Dimensional Interferometer Direction-Finding by Electromagnetic Point Source Radiation Line Method

战斗机综合电子战系统采用二维干涉仪实现方位和俯仰同时测向,用于实现高精度无源定位或引导火控雷达等快速截获目标等。方位干涉仪天线通常安装在机翼前缘等位置,由于受重力或在飞行中颤动等影响,天线出现下倾而不在飞机机体水平面内,现有基于电磁辐射源远场近似平行投射原理进行测向建模过程方法非常复杂且困难。针对非正交二维干涉仪测向难题,提出了一种简洁高效的测向模型,将投射电磁波假设为空间中的辐射点源,由辐射点源到二维干涉仪天线距离差与相位差的关系,再利用辐射点源对应的空间方向线上超过一定距离时的任意点到干涉仪天线相位差近似相等的前提,得到辐射点源空间三维位置的三个方程,求解得到空间三维位置进一步得到电磁波方位俯仰的二维测向公式。对算法模型及其误差进行理论、仿真分析和实际工程验证,结果证明了该方法的有效性。

The 2-dimensional direction-finding interferometer is used in fighter-based integrated electronic warfare system to measure azimuth and elevation simultaneously,for high-precision passive location or guiding fire control radar to acquire targets rapidly.Azimuth interferometer antenna is installed in the front wing of aircraft,because of effect such as weight or vibrating in the flying and so on,antenna will be down from the horizontal plane of aircraft.Existing 2-dimensional direction-finding method which based on the principle of parallel emitting of far field electromagnetic radiation is very sophisticated and difficult.A concise and efficient direction-finding module is proposed to solve the problem of 2-dimensional non-orthogonal direction-finding.The electromagnetic wave is assumed as an electromagnetic point source in space.From the relationship between the distance of electromagnetic point source to 2-dimensional interferometer antenna and the phase difference,and the prerequisite that the phase difference at arbitrary dot in the direction of electromagnetic point source to interferometer antenna will be same approximately if the distance is farther than a specific distance,three equations of spatial 3-dimensional position are got.Then spatial 3-dimensional position can be solved to get the azimuth and elevation.Theoretical,simulation analysis,and practical engineering verification are conducted on the algorithm model and its errors,and the results prove the effectiveness of this method.