摘要
提出一种基于极化敏感阵列的二维波达方向(DOA)和极化参数联合估计算法。首先建立入射信号模型,然后利用重构的x轴、y轴、z轴阵列导向矢量之间的关系计算出入射信号的DOA和极化参数的无模糊粗估计值;同时根据重构阵列导向矢量内在的旋转不变结构估计出x轴和y轴空间相移因子,得到入射信号的高精度无模糊DOA估计。最后利用粗估计精估计相结合的方式进行解模糊,进而完成DOA估计。算法允许阵元间距大于入射信号的半波长,扩展了有效阵列孔径,提高了算法的测向精度。此外,算法避免了复杂的四维谱峰搜索,具有较低的运算复杂度。仿真实验结果验证了算法的有效性和良好的估计性能。
A direction of arrival （DOA） and polarization parameter joint estimation method based on polarization sensitive array is proposed. First, the signal model based on an L-shaped crossed dipole array is built. Then, the coarse DOA and polarization estimation are derived exploiting the relationship among the re- constructed steering vectors of the signals along x-axis, y-axis and z-axis. Meanwhile, the spatial phase factors along x-axis and y-axis are calculated by taking advantage of the inherent rotational invariance structure of the reconstructed steering vectors, with which the fine and ambiguous estimates of DOA are achieved. Finally, the coarse DOA estimation serve as coarse references to disambiguate, leading to the fine and unambiguous estimates of DOA. In the proposed method, the adjacent array elements＇ spacing is allowed beyond half wavelength of the signal, which extends the effective array aperture and improve the DOA estimation accuracy accordingly. Besides, the proposed method avoids the computationally expensive 4-D spectral search, thus its computational complexity is relatively low. Simulation results verify the effectiveness and favorable performance of the proposed method.
作者
王利伟
朱晓丹
王建
陈卓
Wang Liwei Zhu Xiaodan Wang Jian Chen Zhuo(No. 8511 Research Institute of CASIC, Nanjing 210007, Jiangsu, China)
出处
《航天电子对抗》
2017年第3期42-46,共5页
Aerospace Electronic Warfare
关键词
极化敏感阵列
DOA和极化参数估计
导向矢量重构
粗估计和精估计
polarization sensitive array
DOA and polarization estimation
steering vector reconstruction
coarse estimates and fine but ambiguous estimates
