基于互质阵列的外辐射源雷达低仰角估计

Research on Low-Elevation Estimation Based on Coprime Array in Passive Radar

针对外辐射源雷达中低空目标仰角估计分辨率低的问题,本文采用了互质阵虚拟阵列法进行低仰角估计,可有效提高角度分辨率。文章首先论述了互质阵虚拟阵列构造原理,以扩展互质阵列为例详细介绍了虚拟阵列的构造方法,然后通过理论分析与仿真探讨了该方法在低仰角镜像模型中的可行性。仿真中比较了分别用虚拟阵列方法和正交匹配追踪法处理互质阵,以及空间平滑方法处理均匀线阵三种方式在低仰角估计分辨率性能上的优劣,结果表明,在低仰角镜像模型中,互质阵虚拟阵列法的角度分辨率相对其他两种方法有明显优势,不受空间网格限制,而且更适用于低信噪比环境。

Aiming at the problem of low resolution for low-altitude target elevation estimation in passive radar,a low-elevation estimation method for coprime array based on a virtual array is used in this paper,which can improve the angular resolution effectively.Firstly,the principle of constructing a virtual array is discussed,and the extended coprime array is taken as an example to describe the construction method of the virtual array in detail.Then,according to the theoretical analysis and simulation,the feasibility of this method is proved in a low-elevation specular reflection surface model.In the simulation,the low-elevation estimation performance comparison is made between the virtual array method,the compressed sensing method for coprime array,and the spatial smoothing method for uniform linear array.The results show that in the low-elevation specular reflection surface model,the resolution of the coprime array processed by the virtual array method has obvious advantages over the other two methods,which is not limited by the grid and more suitable for low signal-to-noise ratio environment.