Research On Classification Method Of Metal And Nonmetal Materials Based On Passive Millimeter Wave Linear Polarization Difference Ratio

With the continuous development and maturity of millimeter-wave radiation measurement technology,passive millimeter-wave polarization measurement technology has been widely concerned by scholars at home and abroad as an effective method for target information acquisition.Millimeter waves have all-weather characteristics,can penetrate clothing,clouds,etc.,and play an important role in human security,military target detection,fire and fire protection,and terrain measurement.At present,through passive millimeter-wave polarization measurement,the target can be classified into metal and non-metallic materials to obtain the genre information of the target.It is another important detection method in addition to visible light,infrared and radar.It has important scientific research value and national defense.Strategic significance.This thesis first analyzes the difference between the polarization characteristics of metallic materials and non-metallic materials,and proposes a new polarization characteristic quantity---Linear Polarization Difference Ratio(LPDR)Due to the different types of materials,the horizontal and vertical polarization emissivity of the target differ greatly.First,the shortcomings of using Stokes matrix and linear polarization ratio and other polarization characteristics to classify metallic materials and non-metallic materials are explained,and then the construction of linear polarization difference ratio is introduced;The theoretical simulation and simple measurement experiment of the brightness temperature show that the linear polarization difference is better than the LPDR compared to other polarization characteristics for the classification of metallic materials and non-metallic materials;according to the linear polarization difference The value ratio LPDR statistical distribution determines the classification threshold of metallic materials and non-metallic materials,and the development of passive millimeter-wave imaging simulation and imaging experiments verify the effectiveness of the method.The research on classification methods of metal and non-metal materials based on the ratio of passive millimeter-wave linear polarization difference provided in this thesis provides a theoretical basis and method support for further obtaining the target genre information,and promotes passive millimeter-wave polarization measurement technology Development in the field of target information acquisition.