We can estimate two-dimensional spatial spectra of sources in colour Guassian noises by eigen-decomposing the matrix. 对四阶累量混合波达方向矩阵进行特征分解，可实现有色高斯噪声背景中空域信号二维空间谱估计。
From the Fourier space K corresponding to the scattering field of the object, an imaging evaluation mechanism based on the spatial spectral coverage is proposed. 摘要从物体散射场对应的傅里叶空间出发，提出基于空间谱域分布的成像系统定性评价体系。
