频谱分析在DOA估计中的应用

Application of Spectrum Analysis in DOA Estimation

子空间方法的本质是利用噪声子空间与阵列流型之间的正交性对阵列空间采样数据中空间频率进行估计。文章从央拍数据频谱分析的角度来实现这一估计。文中详细推导了窄带情况下DOA和快拍频谱的关系，提出了两种运算量较小、便于工程实现的利用FFT估计窄带DOA的方法。在宽带情况下。详细推导了宽带信号空间频率和时间频率的关系，推导出宽带信号频率对齐的方法，提出了两种直接利用对齐结果来估计宽带DOA的新方法。文中所用方法运算量小，便于硬件实现，仿真结果证明了算法的有效性。

The essence of subspace method is the estimation of spatial frequency in the array sampiing by using the orthotropic between the noise subspace and array manifold. In this paper, the DOA estimation is implemented by spatial spectrum analysis. In narrowband scenario, the relationship between DOA and the spectrum of array snapshot is developed. Two narrowband DOA estimation methods that suitable for engineering implementation were introduced. In wideband scenario, the procession of alignment of sampling data in frequency domain is introduced in detail. Two new wideband DOA estimation methods that directly use the aligned data were brought up. The introduced methods of this paper have little computation burden, and they are easy of implementation by hardware. Simulation results demonstrate the effectiveness of the methods.