Terahertz metamaterial phased array scanning radar super-resolution imaging method based on echo angle priors

Terahertz metamaterial phased array (TMPA) scanning radar is an innovative real-aperture radar system in which the echo signal can be regarded as the convolution between antenna pattern and target scattering coefficient. By employing signal processing methods, it achieves angle resolution beyond the limits of the physical beamwidth. Current super-resolution imaging methods fail to effectively leverage the prior information of the echo angle, thereby limiting their super-resolution capabilities. To address this problem, a super-resolution imaging method of TMPA scanning radar based on the echo angle prior is proposed in this paper. The objective function based on the weighted norm and <i>L</i>₁ regularization norm is constructed by combining the prior information on the echo angle with the sparse feature of the target. Then, the norm ratio method and generalized cross-validation method are introduced to select different hyperparameters. The simulation and experimental results show that the proposed method can effectively improve the angle resolution of scanning radar compared with the traditional sparse angle super-resolution method.