角反射器雷达截面积的快速准确解算是顺利开展合成孔径雷达辐射定标工作的重要基础。用于合成孔径雷达辐射定标的角反射器为电大尺寸,因此,宜采用高频近似法进行雷达截面积的仿真计算。本文利用几何光学对入射波和反射波进行射线追迹以...角反射器雷达截面积的快速准确解算是顺利开展合成孔径雷达辐射定标工作的重要基础。用于合成孔径雷达辐射定标的角反射器为电大尺寸,因此,宜采用高频近似法进行雷达截面积的仿真计算。本文利用几何光学对入射波和反射波进行射线追迹以确定每次入射场及其相对应的照明区域,然后采用Gordan面元积分法对每个照明区域求散射场并累加得到角反射器的雷达截面积,通过与文献、电磁仿真软件FEKO(FEldberechnung für krper mit beliebiger oberflche)的仿真结果比较,证明该方法有效且简单快捷,尤其适用于电大尺寸平板角反射器雷达截面积的快速求解。展开更多
We propose a specific aspheric cylindrical optical system to transform Gaussian beam to flat-top and rectangular beam. The Gaussian beam shaping system is composed of dual orthogonal aspheric cylindrical lenses. The p...We propose a specific aspheric cylindrical optical system to transform Gaussian beam to flat-top and rectangular beam. The Gaussian beam shaping system is composed of dual orthogonal aspheric cylindrical lenses. The principle of shaping Gaussian beam is studied theoretically. The mapping function of arbitrary rays in an incident plane and an image plane is deduced based on the law of energy conservation, and the real ray tracing method is adopted to design the shaping system. Finally, the lens system is processed by single point diamond turning techniques. Testing results indicate that the system achieves the theoretical expectation, and the uniformity of flat-top and rectangular beam is 88.2%. The method is not only simple but also practical.展开更多
A planar-hyperlens-based imaging device is presented in this paper. Based on the structure of hyperbolic dispersion metamaterial and with the ability of collecting the evanescent waves from the object, the planar hype...A planar-hyperlens-based imaging device is presented in this paper. Based on the structure of hyperbolic dispersion metamaterial and with the ability of collecting the evanescent waves from the object, the planar hyperlens can deliver and magnify the super-resolution details of a planar object to the extent that a traditional microscopic objective can resolve them. The super-resolution magnification imaging principle of the device was analyzed, and the relations of the imaging resolution and magnification with the structure parameters of the device were deduced. With careful design, the effectiveness of the device was confirmed in a series of展开更多
文摘角反射器雷达截面积的快速准确解算是顺利开展合成孔径雷达辐射定标工作的重要基础。用于合成孔径雷达辐射定标的角反射器为电大尺寸,因此,宜采用高频近似法进行雷达截面积的仿真计算。本文利用几何光学对入射波和反射波进行射线追迹以确定每次入射场及其相对应的照明区域,然后采用Gordan面元积分法对每个照明区域求散射场并累加得到角反射器的雷达截面积,通过与文献、电磁仿真软件FEKO(FEldberechnung für krper mit beliebiger oberflche)的仿真结果比较,证明该方法有效且简单快捷,尤其适用于电大尺寸平板角反射器雷达截面积的快速求解。
基金supported by the Funding Project for Surveying and Mapping Geographic Information Public Industry(No.20142007)
文摘We propose a specific aspheric cylindrical optical system to transform Gaussian beam to flat-top and rectangular beam. The Gaussian beam shaping system is composed of dual orthogonal aspheric cylindrical lenses. The principle of shaping Gaussian beam is studied theoretically. The mapping function of arbitrary rays in an incident plane and an image plane is deduced based on the law of energy conservation, and the real ray tracing method is adopted to design the shaping system. Finally, the lens system is processed by single point diamond turning techniques. Testing results indicate that the system achieves the theoretical expectation, and the uniformity of flat-top and rectangular beam is 88.2%. The method is not only simple but also practical.
基金This work is supported by the National Natural Science Foundation of China under Grant Nos 10904118, 11374235, 61007024, and 61271150.
文摘A planar-hyperlens-based imaging device is presented in this paper. Based on the structure of hyperbolic dispersion metamaterial and with the ability of collecting the evanescent waves from the object, the planar hyperlens can deliver and magnify the super-resolution details of a planar object to the extent that a traditional microscopic objective can resolve them. The super-resolution magnification imaging principle of the device was analyzed, and the relations of the imaging resolution and magnification with the structure parameters of the device were deduced. With careful design, the effectiveness of the device was confirmed in a series of
