Research On Fast Millimeter Wave Imaging Algorithm Based On Sparse Scan Array

There is a growing trend that terrorist attacks have happened frequently both at home and abroad in recent years.Global security and protection is facing a serious challenge.In this context,in public places such as airports,customs and train stations,inspections using X ray,metal safety door and human labor are employed in security check.However,with so many steps to follow,the whole process is time-consuming,the crowd blocking the passage,proving hidden danger.Therefore,the existing security check system needs higher speed,more convenience and comprehensiveness and greater security and smartness.Millimeter-wave imaging technology provides a solution of high-resolution imaging of human bodies in a targeted scenario and hidden objects by using the advantages of millimeter wave's good penetration,minimal wavelength and no ionizing radiation to human bodies.However,the existing millimeter-wave imaging system generally adopts many antenna channels to meet the purpose of high-resolution and real-time imaging,resulting in a great increase in cost.This paper is to explore the improvement of the scanning mode and imaging algorithm,in order to achieve fast imaging and highresolution imaging with sparse array,thereby reducing the cost of millimeter-wave imaging system and improving the imaging efficiency.This paper mainly contains the following five parts:(1)The application of millimeter-wave imaging technology in the field of security check against the backdrop of the security and protection's status quo.This part discusses the history,status quo and prospect of active and passive directions of millimeter-wave imaging technology are analyzed at home and abroad.(2)The overview of methods and principles used in millimeter-wave imaging technology,with respect to data collection and imaging algorithm.(3)A progressive imaging algorithm that can scan targets and form images simultaneously to solve the problem that narrow-band millimeter-wave holography cannot image three-dimensional targets.At the same time,there is a possible change in traditional narrow-band holographic imaging technology which needs to scan the entire targeted scenario to collect data.The progressive imaging method reduces operation merging steps and increases the imaging speed.(4)The regularization denoising method was introduced into the post-processing process of the reconstruction image of the millimeter-wave imaging system.The denoising research was conducted on the reconstructed image of the progressive imaging algorithm,and the appropriate regularization parameters were found out to obtain a better noise-reduced image.The application value of this method is analyzed.(5)Summary of the whole paper.The research direction and the guide and learning received during my postgraduate years may serve to provide fresh thinking of millimeterwave security imaging technology that helps future development of this system.