中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Sheared-beam imaging target reconstruction based on all-phase spectrum analysis

文献类型:期刊论文

作者Chen Ming-Lai; Luo Xiu-Juan; Zhang Yu; Lan Fu-Yang; Liu Hui; Cao Bei; Xia Ai-Li; Liu Hui(刘辉)
刊名acta physica sinica
出版日期2017-01-20
卷号66期号:2
关键词sheared-beam imaging speckle all-phase spectrum analysis target reconstruction
ISSN号1000-3290
其他题名基于全相位谱分析的剪切光束成像目标重构
产权排序1
英文摘要

sheared-beam imaging technique is considered to be a non-conventional speckle technique for remote imaging through turbulent medium. in this high resolution imaging technique, three beams are splitted from one laser source and illuminate a remote target simultaneously in shearing distribution. each beam is modulated by a tiny frequency shift so that these beams can interfere and beat together. the returning speckle signals are received by an array of detectors. the primary algorithm for the signal processing and image reconstruction has been developed previously. however, the reconstructed image is deteriorated by the frequency drifting error and spectrum leakage. these frequency errors are always from the transmitter and scattered signals that are caused by spectrum-shift errors from acousticoptic modulators, atmospheric turbulence, doppler effects of moving targets, etc. to solve the problems mentioned above, in this paper we propose a new image reconstruction algorithm based on the all-phase spectrum analysis theory. the all-phase fast fourier transform (fft) spectrum analysis theory, which can effectively inhibit spectral leakage and correct speckle spectrum, is used to process the scattered signals. by searching for the accurate positions of the beat frequency components in the transformed frequency domain data, the speckle amplitude and phase difference frames can be extracted accurately. based on the speckle phase-difference frames, the phase distribution of the wavefront is derived by least-square algorithm. the phase distribution in grid is highly coherent, in which each point is related to the phases of its four nearest neighbors. if an initial phase map is given or preset, the phase map of the wavefront can be estimated accurately by gauss-seidel method. meanwhile, the amplitude of wavefront is obtained by the algebraic operation of speckle amplitude frames. the reconstructed wavefront is inverse fourier transformed to yield a two dimensional image. a series of speckled images of the same object are averaged to reduce the speckle noise. the proposed method improves the ability of system imaging in the actual imaging environment. simulation experiments validate the effectiveness of the proposed algorithm, and simulation results show that the proposed image reconstruction algorithm can inhibit the frequency errors from influencing imaging quality when there exist frequency errors in scattered signals. thus, the imaging quality of the algorithm based on the all-phase fft method is much better than that of the algorithm based on the traditional fft method. the substantial usage of this technique is widely spread after the reconstruction algorithm has been optimized.

WOS标题词science & technology ; physical sciences
类目[WOS]physics, multidisciplinary
研究领域[WOS]physics
关键词[WOS]least-squares ; coherent ; field
收录类别SCI ; EI ; CSCD
语种英语
WOS记录号WOS:000397107800013
源URL[http://ir.opt.ac.cn/handle/181661/28747]  
专题西安光学精密机械研究所_光电测量技术实验室
作者单位Chinese Acad Sci, Xian Inst Opt & Precis Mech, Xian 710119, Peoples R China
推荐引用方式
GB/T 7714
Chen Ming-Lai,Luo Xiu-Juan,Zhang Yu,et al. Sheared-beam imaging target reconstruction based on all-phase spectrum analysis[J]. acta physica sinica,2017,66(2).
APA Chen Ming-Lai.,Luo Xiu-Juan.,Zhang Yu.,Lan Fu-Yang.,Liu Hui.,...&Liu Hui.(2017).Sheared-beam imaging target reconstruction based on all-phase spectrum analysis.acta physica sinica,66(2).
MLA Chen Ming-Lai,et al."Sheared-beam imaging target reconstruction based on all-phase spectrum analysis".acta physica sinica 66.2(2017).

入库方式: OAI收割

来源:西安光学精密机械研究所

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