2D DOA Estimation of LFM Sources Using FRFT-based and Mode-space-based Algorithm

Based on fractional Fourier transform (FRFT) and mode-space algorithm of circular arrays, a new 2D direction of arrival (DOA) estimation algorithm of linear frequency modulation (LFM) signals is proposed in this paper. Firstly, we construct a new array data model based on the fact that the LFM signal has the energy concentrated performance in the fractional Fourier transform domain (FRFD), and then we use the mode-space algorithm to get a new array manifold matrix of the virtual linear array. Finally we use the least square (LS) method to realize 2-D DOA estimation of LFM signals and the simulation results verify the effectiveness of the algorithm proposed by this paper.