Research On Technology Of Subsurface Target Detection Based On Multitemporal And Multispectral Infrared Image

The technology of subsurface targets detection has important military and civilian value. It has been widely used in underground pipeline inspection, mine detection and other fields. The traditional infrared technology of subsurface targets detection through segmentation or clustering method to detect the information of the location and cross-sectional area of subsurface targets, lacking of research on the the relationship between the regional temperature distribution and thermal physical properties of the subsurface targets. They also pay little attention on the research to use the multi-temporal and multi-spectral information. To get more information of subsurface targets, a new infrared detection technology based on multi-temporal multi-spectral infrared images is proposed in this thesis. It makes full use of the thermal model and the multi-temporal and multi-spectral information of infrared images, which not only can detect the information of the material, height and depth of subsurface targets but also the information of location and cross-sectional area of the targets. So, the main content of this thesis is as following:Firstly, we research on the mathematical model of temperature change of the region containing subsurface targets, and reveal the relationship between the regional temperature changes and thermal physical properties and buried position of the subsurface targets. Then we give the initial and boundary conditions according to the heat teansfer conditions between the the region and the environment to solve the model. So the model can accurately predict the distribution of regional surface temperature.Secondly, since the existence of subsurface targets influences the thermal physical properties of the surrounding area, causing the temperature differences over time in the regional surface, which reflected in the infrared images, is the gray value changes over time. So a new infrared technology of subsurface targets detection is proposed based on the thermal model. We use real temporal infrared images to get the temperature distribution of the region surface which compared with the solution of the mathematical model. By continuously changing the value of the thermal model parameters, we can get a solution which consistent with the temperature distribution obtained by the real temporal infrared images, and then we complete the detection of subsurface targets.Finally, the application of the multi-spectral information to detect the subsurface targets is researched and a new technology of subsurface target detection based on multi-temporal and multi-spectral infrared image is proposed. By researching the radiation characteristics of the bands we find a way to using fine spectral resolution to improve the inversion of regional surface temperature distribution. Experiments show that this method significantly improved the detection accuracy.