远场环境下基于方向角的测向交叉定位技术研究

A study on the lateral cross localization using direction angle in far-field environment

针对远场条件下小孔径阵列被动定位在强干扰下精度差的问题,提出基于方向角的测向交叉定位算法。分析侧向交叉定位方法的工作机理,构建改进的目标定位几何模型和数值模型;利用构建的模型建立目标估计预测方程,并对非线性预测方程进行线性化处理,将预测方程在参考点处按泰勒级数展开,获得修正方程;通过迭代过程的优化控制获得目标的无偏渐近估计,实现目标精确定位;对所提算法的主要误差来源进行分析,研究不同误差项对目标定位精度的影响。仿真实验表明,提出的算法能有效的对目标进行定位,在方向角误差和背景噪声较大时定位精度明显高于传统定位算法,具有更优的定位性能。

For the problem of poor accuracy in passive location with far field and small aperture array under strong interference,a location algorithm was proposed based on direction angle lateral cross.Firstly the principle of cross lateral positioning method was analyzed to construct the improved targeting geometrical and numerical models.Then target estimate prediction equation was established by the building model and the nonlinear prediction equation was processed by linearization.The prediction equation was developed at the reference point with Taylor series and the correction equation was obtained.The goal's progressive unbiased estimate was obtained by optimizing control of iterative process to achieve target pinpoint.The main error factors of the proposed algorithm were analyzed to study the impacts on the target location accuracy of different errors.Simulation results show that the proposed algorithm can locate the target effectively and has better positioning performance than traditional location algorithms in large direction angle error and background noise.