Airborne Validation of Ground-Object Detection from Polarized Neutral-Point Atmosphere
YANG Shang-qiang1,2, GUAN Gui-xia1, ZHAO Hai-meng2, ZHAO Hong-ying2, YANG Bin2, ZHANG Wen-kai1,2, TAN Xiang2,4, WU Tai-xia3, YAN Lei2*
1. College of Information Engineering, Capital Normal University, Beijing 100048, China 2. Beijing Key Lab of Spatial Information Integration and Its Applications, Peking University, Beijing 100871, China 3. Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China 4. Specialized Forces College of Chinese Armed Police Force, Beijing 102202, China
Abstract：Based on the objects polarization effects, polarization is a newly emerging method in the field of remote sensing. Both objects and atmosphere have polarization effects, however, the atmospheres polarization effects are much stronger than that of objects. Consequently, atmosphere polarization effects will interfere or even cover objects when observing with sensors. How to maximally eliminate the polarized effects generated by the atmosphere is a crucial problem in polarization remote sensing. Atmospheric neutral point is an area where the degree of atmosphere polarization is near to zero; therefore, if sensors are set up in this area, atmosphere polarization would be greatly eliminated, which is the main content of separating the effects between objects and atmosphere by its neutral point method. In this paper, after processing and analyzing the experimental data got from the first polarization remote sensing flight experiment with atmosphere neutral point, the degree of polarization images captured in neutral and non-neutral point area were obtained, and it can be seen that the main value of polarized degree of images got in neutral point area was obviously smaller than that in non-neutral point area. The results showed that the theory mentioned above was logical and practical. An innovation in our study is that the requirements needed in polarization remote sensing flight with neutral point were clarified. In the meantime, a qualitative conclusion was drawn that observing with longer wavelength is more applicable to polarization remote sensing.
Key words：Polarization remote sensing;Atmospheric neutral point;Separation of the polarized effects between objects and atmosphere
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