摘要
针对干涉阵列米波雷达方向估计中的模糊问题,该文提出了基于矩阵完型的解模糊算法。该方法将干涉技术中的辅助阵元解模糊方法扩展到干涉阵列中,通过增加适当的辅助阵元,使干涉式阵列成为完型阵列,再依次采用直接增广法、MUSIC算法及关联法实现干涉阵列方向估计的解模糊,从而得到高精度无模糊的方向估计。为了估计相干源的波达方向,该文根据干涉阵列结构的特点及空间平滑算法的原理也提出了干涉阵列的空间平滑算法。仿真结果和实测数据验证了矩阵完型解模糊算法和干涉阵列的空间平滑算法的正确性与有效性,也表明了该文的解模糊方法具有计算量小,实时性高等特点。
Due to the ambiguities in Direction Of Arrival(DOA) estimation for an interferometric array VHF radar,a novel ambiguity-resolution algorithm based on matrix completion is proposed.The algorithm with additional elements for ambiguity resolution in interferometry is extended to the interferometric array.Then the interferometric array becomes a completion array or fully augmentable array.The well-known Direct Augmentation Approach(DAA),MUSIC(MUltiple SIgnal Classification) and association method are orderly utilized to resolve the ambiguities and obtain nonambiguous but low-variance DOA estimation.An interferometric spatial smoothing technique for decorrelating coherent signals is also proposed in terms of the array geometry.Simulation results and the results of real data demonstrate the validity and effectiveness of the proposed algorithms.The matrix-completion algorithm has some computational and real-time advantages at the cost of a small increase in hardware.
引文
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