Research On Active Millimeter Wave Imaging Algorithm

In recent years,as the threat of terrorism has increased,people need to establish imaging systems to detect such threats and ensure personal safety.Various methods are currently being investigated for the detection of dangers,including: X-ray imaging,infrared imaging,optical detection,terahertz imaging,and millimeter wave imaging.Millimeter waves which can penetrate clothing have no ionizing radiation.Combined with these advantages of millimeter wave,millimeter wave imaging technology has been widely used in many fields such as human security inspection and military reconnaissance.This thesis studies the imaging of the target scene,and its research background is mainly based on the security inspection at the airports and wharves.This thesis focuses on the engineering implementation of the active millimeter wave imaging algorithm.This thesis mainly studies the millimeter wave imaging algorithm.Based on the research of traditional algorithms,the traditional algorithm is improved.The main research contents are as follows:Firstly,the traditional two-dimensional range doppler algorithm is studied,and the shortcomings of the traditional algorithm are improved by introducing the second range compression and the dechirp operation.When the bandwidth of the signal is very large,the traditional receiving method is replaced by the dechirp operation.Finally,the simulation experiments that are compared with the traditional two-dimensional range doppler algorithm is carried to verify the effectiveness of the improved algorithm.The traditional two-dimensional range migration algorithm is studied,and the two-dimensional range migration algorithm of dechirp operation is analyzed and studied.The interpolation problem used in the algorithm is improved by introducing the non-uniform fast fourier transform bases on that.The non-uniform fast fourier transform is used to replace the Stolt interpolation to reduce the interpolation error and improve the imaging speed.Finally,the effectiveness of the improved two-dimensional range migration algorithm is verified by simulation experiments and the measured data.