Research On Imaging Algorithm Of Terahertz Frequency Modulated Continuous Wave Radar

Terahertz(THz)waves are conducive to generate the signal with a large bandwidth,and THz radiation is non-ionizing which is harmless to humans.Above all,THz technology has broad application prospects in high resolution imaging and human security inspection.In this paper,the Terahertz Frequency Modulated Continuous Wave(THz-FMCW)radar imaging algorithm is studied.The THz-FMCW radar imaging system with operating frequency from 170 GHz to 220 GHz is introduced.The THz-FMCW radar signal model is established and the principle of synthetic aperture technology is given.The THz-FMCW radar imaging algorithm based on wavenumber domain is studied.Firstly,the flow of THz-FMCW radar imaging algorithm based on RMA is deduced.In order to solve the computational complexity problem existing in RMA,THz-FMCW radar imaging algorithm based on NUFFT is introduced.Through the point-target simulation and measured data imaging experiments,two kinds of THz radar imaging algorithms based on wavenumber domain are verified,and the performance of the algorithm is compared and analyzed.THz-FMCW radar imaging algorithm based on Compressive Sensing(CS)is studied in this paper.An overview of compressive sensing theory is presented,and the flow of THz-FMCW radar imaging algorithm based on compressive sensing is deduced.The THz-FMCW radar imaging reconstruction algorithm:OMP algorithm,CoSaMP algorithm,SLO algorithm,NSLO algorithm and BCS reconstruction algorithm based on RVM are studied,and the flow of each reconstruction algorithm is deduced.Through the point-target simulation and measured data imaging experiments,the above THz-FMCW radar imaging reconstruction algorithm is validated.The performance of the CS-based THz-FMCW radar imaging reconstruction algorithm was evaluated using reconstruction time of imaging algorithm and algorithm reconstruction error as evaluation criteria.