Terahertz Inverse Synthetic Aperture Radar Near-field Imaging Algorithm Using Green’s Function Decomposition

In this paper, an imaging algorithm for terahertz inverse synthetic aperture radar using the Green’s function decomposition is proposed to implement near-filed imaging. Combined with the Superheterodyne receiver mode of terahertz radar, the model of terahertz target echo in the near-field is builded and analyzed. The spherical wave which is represented by Green’s function is decomposed to the superposition of plane wave components in two dimensions. After completing the operators of the filtering compensation and two dimension inverse fast Fourier transform, the target image of terahertz inverse synthetic aperture radar in the near-field condition. To demonstrate the imaging performances of our method, numerical simulations and experiments are conducted. Comparing the simulation results based on the two dimensional fast Fourier transform method and the proposed algorithm respectively, the feasibility of the proposed algorithm is verified. Finally, the real experimental data are used to validate the performance of the proposed algorithm and the experimental results demonstrate that our method can obtain a good imaging performance.