信息工程大学信息系统工程学院, 河南郑州 450001
针对现有蒸发波导条件下无线电系统性能研究过程中, 忽略了蒸发波导水平非均匀特性影响, 探讨了水平非均匀蒸发波导条件下的非互易性。利用马尔科夫过程模拟蒸发波导水平非均匀特性, 结合抛物方程法计算电波传输损耗, 仿真分析了雷达电磁参数对非互易性的影响。仿真结果表明: 蒸发波导环境下电波传播的非互易性在波导水平非均匀时无法忽略, 天线高度和电波频率对非互易性的影响较大。天线高度越高, 电波频率越大, 则非互易性越强。
蒸发波导 水平非均匀 非互易性 抛物方程 evaporation duct horizontal inhomogeneous non -reciprocity parabolic equation 太赫兹科学与电子信息学报
2018, 16(3): 458
Author Affiliations
Abstract
1 Biomedical Engineering, University of Connecticut, Storrs, Connecticut 06269, USA
2 Electrical and Computer Engineering, University of Connecticut, Storrs, Connecticut 06269, USA
Controlling photographic illumination in a structured fashion is a common practice in computational photography and image-based rendering. Here we introduce an incoherent photographic imaging approach, termed Fourier ptychographic photography, that uses nonuniform structured light for super-resolution imaging. In this approach, frequency mixing between the object and the structured light shifts the high-frequency object information to the passband of the photographic lens. Therefore, the recorded intensity images contain object information that is beyond the cutoff frequency of the collection optics. Based on multiple images acquired under different structured light patterns, we used the Fourier ptychographic algorithm to recover the super-resolution object image and the unknown illumination pattern. We demonstrated the reported approach by imaging various objects, including a resolution target, a quick response code, a dollar bill, an insect, and a color leaf. The reported approach may find applications in photographic imaging settings, remote sensing, and imaging radar. It may also provide new insights for high-resolution imaging by shifting the focus from the collection optics to the generation of structured light.
Imaging systems Digital holography Microscopy Computational imaging Photonics Research
2015, 3(1): 01000019
