吴双, 袁野, 吴微微, 袁乃昌. 一种宽带相干信源的无网格超分辨DOA估计方法[J]. 电波科学学报, 2020, 35(5): 648-655. doi: 10.13443/j.cjors.2020041102
      引用本文: 吴双, 袁野, 吴微微, 袁乃昌. 一种宽带相干信源的无网格超分辨DOA估计方法[J]. 电波科学学报, 2020, 35(5): 648-655. doi: 10.13443/j.cjors.2020041102
      WU Shuang, YUAN Ye, WU Weiwei, YUAN Naichang. A method of grid-less super-resolution DOA estimation for wideband coherent sources[J]. CHINESE JOURNAL OF RADIO SCIENCE, 2020, 35(5): 648-655. doi: 10.13443/j.cjors.2020041102
      Citation: WU Shuang, YUAN Ye, WU Weiwei, YUAN Naichang. A method of grid-less super-resolution DOA estimation for wideband coherent sources[J]. CHINESE JOURNAL OF RADIO SCIENCE, 2020, 35(5): 648-655. doi: 10.13443/j.cjors.2020041102

      一种宽带相干信源的无网格超分辨DOA估计方法

      A method of grid-less super-resolution DOA estimation for wideband coherent sources

      • 摘要: 由于无网格(grid-less)稀疏重构方法的波达方向(direction of arrival,DOA)估计数学模型为单快拍形式,因此该方法只有在噪声电平趋近于零时才具有优越的性能.为了提高grid-less方法在信噪比(signal-to-noise ratio,SNR)较低时宽带相干信源的估计性能,提出了一种多快拍grid-less DOA估计方法.首先,对多快拍阵列观测矢量实施奇异值分解(singular value decomposition,SVD)获得观测矩阵的时域信号子空间,通过观测矩阵到时域信号子空间的投影实现观测矩阵的降噪;然后,为了不增加多快拍计算复杂度,将降噪后观测矩阵的列向量加权累加处理得到单快拍形式;最后,从理论上证明了本文提出的GL-SVD方法求解的模型是凸的,能够实现宽带信号DOA的精确重构.仿真结果表明,该方法在低SNR以及宽带相干信源情况下的估计精度都高于L1范数最小化奇异值分解(L1-norm minimum singular value decomposition,L1-SVD)和离格稀疏贝叶斯推断奇异值分解(off-grid sparse Bayesian inference singular value decomposition,OGSBI-SVD),且在较小角度间隔的情况下具有更高的估计概率和分辨率.

         

        Abstract: Because the direction of arrival (DOA) estimation mathematical model of the grid-less sparse reconstruction method is in the form of single snapshot, the method has superior performance only when the noise level approaches zero. In order to improve the performance of the grid-less method when the signal to noise ratio (SNR) is low, a multi-snapshots grid-less DOA estimation method is proposed. First, we perform singular value decomposition (SVD) to get the time-domain signal subspace of the observation matrix and achieve noise reduction of the observation matrix by projection from the observation matrix to the time-domain signal subspace. Then, in order not to increase the computational complexity of multi-snapshot, the column vectors of the observation matrix are weighted and accumulated to obtain the single snapshot form. Finally, it is proved theoretically that the model solved by the GL-SVD method proposed in this paper is convex and can achieve the precise reconstruction of wideband signal DOA. The sim- ulation results show that the proposed method has higher estimation accuracy than L1 norm minimum singular value decomposition (L1-SVD) and off-grid sparse Bayesian inference singular value decomposition (OGSBI-SVD) with low SNR and wideband coherent sources. In addition, it has higher estimated probability and resolution in the case of smaller angle interval.

         

      /

      返回文章
      返回