Review of Active Millimeter Wave Imaging Techniques for Personnel Security Screening

This paper reviews recent progress of active millimeter wave (mmW) imaging techniques for personnel security screening. With the ability to penetrate clothing and the promised millimeter scale spatial resolution, mmW imaging has been widely pursued for personnel surveillance without the usual concern for radiation safety. A brief development history of mmW imaging is introduced. An overview of imaging research and developmental achievements, along with antenna considerations based on quasi-optical geometry, phased reflector array, monostatic array, and multistatic array, is provided. Design considerations related to practical applications, including system calibrations, walk-through system (WTS), portable system, and compressive sensing (CS), are also discussed.