Doppler aliasing free micro-motion parameter estimation algorithm based on the spliced time-frequency image and inverse Radon transform

Micro-Doppler is induced by the micro- motion of target and serves as an important characteristic for target recognition once extracted via parameter estimation, but it is generally too significant to result in aliasing in terahertz band. To solve this problem, we analyze the theoretical model and characteristics of aliased micro-Doppler and propose a Doppler aliasing free micro-motion parameter estimation algorithm based on the combination of spliced time-frequency image and the Inverse Radon transform. The basic idea is getting a certain number of aliased time-frequency images spliced, and then make Inverse Radon transform to the spliced image and extract micro-motion parameters. The simulation results show that this method has the advantages of high precision and strong noise suppression and can estimate parameters of aliased micro-Doppler correctly and effectively.