| Whether it is in the military or civilian, the study of rough surface electromagnetic scattering properties have a significant academic value and broad application prospects, the feature electromagnetic scattering and electromagnetic inverse scattering research plays an extremely important role in the microwave remote sensing. Due to the presence of complex background interference environment factors, which has a certain influence on the accuracy of experimental results, thus backscatter statistical modeling research becomes more necessary, Combination of domestic and international experience in the existing model of backscattering, the paper obtains a backscattering engineering statistical model.In electromagnetic scattering theory, the relevant knowledge of rough surface electromagnetic scattering is described, and the small slope approximation method and perturbation method is introduced, then the electromagnetic scattering is introduced, with the perturbation method, a approximate study of the electromagnetic of the layered rough surface is made, finally, the numerical calculation and analysis of single layered and layered rough surface are made.In the experimental measurements, the significance of of typical surface backscattering measurements is described, and the specific process and specific parameter settings, measurement system architecture and principles are described, and then the meaning of calibration experiments and principles are described in detail. Calibration experiment is divided into the darkroom scaling and outdoor calibration, calibration experiments related to outdoor electromagnetic backscattering measurement accuracy, so its significance is self-evident. In next chapter, a variety of surface measurement locations and measurement processes are described in detail, and finally the raw measurement data processing methods, processes and results are described, and the results of data processing are analyzed.For different features, numerical calculations is made with different electromagnetic scattering theory, contrast with the measured data of Chinese radio, the results of both agree with each other well, which prove the accuracy and feasibility of the theoreticalapproach. For some angle, the difference between the theoretical and experimental values is relatively large, with the electromagnetic scattering theory,appropriate analysis is made in this chapter.Based on genetic algorithm and particle swarm algorithm, typical surface equivalent roughness and permittivity are inversed, with two methods, typical surface equivalent roughness and permittivity are inversed The parameters through several times inversion and parameter values derived from experimental measurements is very close, and then the correctness of the inversion is proved, and the parameters of inversion into the theoretical formula to calculate, after the results are compared with the experimental results of backscattering measurements, the results prove that the inversion is practical.Combination of domestic and international experience in the existing model of backscattering, China Aerospace Science and Technology and the measured data of Shanghai Radio 802, and mathematical optimization methods, the paper obtains a typical surface backscattering statistical model, then this model fitting results and Ulaby fitting results are compared with experimental data,and found that this model applies to simulate most of the surface backscatter, and accuracy is relatively high, with a good practical value. |
