基于波束域的米波雷达低仰角波达方向估计  

Estimation of direction-of-arrival for meter-wave radar based on beam-space at low-angle environment

作　　者：吴向东[1] 马仑[1] 梁中华[1] 

机构地区：[1]长安大学信息工程学院,陕西西安710064

出　　处：《电波科学学报》2014年第6期1147-1152,共6页Chinese Journal of Radio Science

基　　金：陕西省自然科学基金(No.2011JQ8041);F中央高校基本科研业务费专项基金(No.2013G1241116)

摘　　要：针对米波雷达低仰角工作时除了收到目标的直达波外,还会收到与直达波相干的地(海)面反射的多径信号,提出了一种基于波束域的米波雷达低仰角波达方向估计的新算法.利用阵列输出数据协方差矩阵构造一个Toeplitz矩阵,以实现对雷达回波数据的解相干;在波束域对降维后的数据协方差矩阵应用基于信号子空间的角度超分辨算法实现波达方向估计;最后,研究了波束域下米波雷达低仰角波达方向估计的特点,分析了不同信噪比、波束个数对算法性能的影响.所提算法不但可以有效地克服多径效应,还极大地降低了运算量,理论分析和计算机仿真都证明了新算法的优越性.The echo waves of radar received consist of direct waves and multipath waves which is reflected from earth （sea） surface and coherent with direct waves. A new esti- mation of direction-of-arrival （DOA） algorithm based on beam-space signal processing at low-angle environment is presented. First, we use array covarianee matrix to construct a Toeplitz matrix to achieve decorrelation for the echo waves; then, we achieve the esti- mation of DOA using super-resolution method based on signal subspace to reduced di- mension covariance matrix in beam domain at low elevation angles; finally, we study the characteristic of the estimation of DOA in beam-space at low elevation angles, analyze the influence of different SNR and number of beam on our algorithm. This method can not only overcome multipath effect effectively but also reduce the complexity and com- putation for the estimation of DOA. Theoretical analysis and simulation results demon- strate the merits of the new algorithm.

关 键 词：多径效应 相干信号 波束域 TOEPLITZ矩阵 

分 类 号：TN957[电子电信—信号与信息处理]