查询词典 SAR

Many new detection techniques are proposed, that include: To overcome the faults of cross-terms and short unambiguity range for the common Wigner-Ville Distribution , short-time Fourier transform and Gabor transform are applied to SAR moving target detection. To improve the detection performance of WVD in noise environment, a new technique based on the Cross-WVD is proposed. The application of fractional Fourier transform to chirp signal detection is analyzed and extended to SAR moving target detection. To eliminate the restriction of chirp-Fourier transform, a new modified definition is proposed and applied to SAR moving target detection. To detect multiple moving targets whose scattering intensities are different heavily, the CLEAN technique is combined with the above techniques and the ideal detection performance is achieved. At last, the whole dissertation is concluded.

具体的研究成果如下：针对常用的Wigner-Ville分布在多目标情况下存在交叉项，并且多普勒不模糊范围小的缺点，提出将短时Fourier变换和Gabor变换应用于SAR运动目标检测，分析了其优势所在；为进一步提高Wigner-Ville分布低信噪比条件下的信号检测能力，提出基于互Wigner-Ville分布的运动目标检测方法；分析了分数阶Fourier变换在线性调频信号检测中的应用，提出基于分数阶Fourier变换的运动目标检测算法；对离散Chirp-Fourier变换的定义进行了修正，提出修正的离散Chirp-Fourier变换，克服了限制其应用的约束条件，并用于SAR运动目标检测当中；强度相差较大的多运动目标检测历来是机载SAR技术的一个重点和难点，我们将CLEAN思想融入上述多种算法当中，良好地解决了该问题。

Combining detection and identify of SAR imagery this paper summarized study evolution of SAR image on demising,characters of line and texture extraction, image segmentation and target detection; Introduced up to date study progress; ultimately analyzed program about detection and identify of SAR image in inland and overseas thing and prospected development in future.

本文结合SAR图像检测和识别应用技术的发展过程，综述了SAR图像在噪声抑制、线状特征和纹理特征提取、图像分割和目标检测等方面的研究进展；介绍SAR图像检测和识别的最新研究情况；最后分析当今国内外SAR图像检测和识别所面临的问题，并对未来发展进行展望。

Notes: By taking mainland China and Hong Kong SAR together, the second panel includes imports and exports to the mainland that are intermediated through Hong Kong SAR (during 2002–04, about one-fifth of the mainland's merchandise trade was intermediated through Hong Kong SAR).

中国的经常帐户盈余2004年增长了大约700亿美元，而贸易总盈余占了这一增长的大部分。2001年到2004年间，中国的出口以每年平均30%的惊人速度增长（进口以同样速度增长，但进口的水平仍然低于出口）。

SAR image autofocus algorithm based on SAR echo is mainly studied in this dissertation.

本文重点讨论了基于SAR回波数据的SAR图像自聚焦算法。

With the development of various SAR imaging technique and improvement of SAR imaging quality, the resolution of range and azimuth has been improved to a high level.

随着SAR的各种成像处理技术的发展，SAR的成像质量不断提高，其距离和方位向已达到很高的的分辨力。

First, a non-parametric density estimate method based on kernel function is adopted to estimate the statistic distribution of the SAR images, and then, the SAR images is segmented with Markovian contexture by maximizing a MAP estimator, taking the former estimation as its likelihood term.

该算法首先采用基于核函数的非参数方法估计SAR图像的统计分布，然后将此统计量作为图像分割的似然函数，利用马尔可夫上下文约束进行SAR图像分割。

In this dissertation, based on the extraction of meaningful polarization information, the polarimetric speckle reduction, polarimetric contrast enhancement, polarimetric classification and ship detection in polarimetric SAR images are systemically studied. During the study, some new concepts and methods are introduced, which are supported by the application to measured Pol-SAR data. The innovations of this dissertation are as follows: 1 A simplified schem is proposed to reduce the complexity of scattering-model-based speckle filtering. 2 Extend the expression of polarimetric correlation coefficient to help distinguishing targets. In addition, introduce the quantized parameters of polarimetric signature so as to show the differentiae in quantity in co-polar power, cross-polar power and shapes of polarization signatures among targets. 3 Define a new parameter of difference degree between targets, which can be used for express the difference between both coherent and distributed scatters.

论文在较系统的研究目标特征量提取方法和特征量所包含的物理意义的基础上，对极化SAR图像降斑、极化对比增强、极化SAR图像分类以及极化SAR图像中海上舰船目标检测等方面进行了研究，并提出了一些新的概念和方法，对实测数据的处理结果表明，这些新的概念和方法对于极化SAR信息处理是有效的，本文的主要创新成果包括以下方面： 1）针对基于预分类的MMSE极化降斑方法实现过程非常复杂的问题，提出了简化方案，并验证了方案的有效性； 2）扩展了极化相关系数的表示方法，这种扩展增强了极化相关系数对目标的区分效果；另外还提出了极化特征图量化参数，可以从量上表征不同目标间相同极化和交叉极化的回波功率差异和极化特征图形状差异； 3）定义了目标间的差异度参数，它不仅可以用于描述相干目标，还可以用于描述分布目标的差别程度。

The validities of amplitude features and their extraction method suitable in high-frequency SAR image are analyzed when they are used in UWB SAR image. An extraction approach of amplitude feature based on target contour is presented, and the corresponding effective amplitude features are proposed. The old dihedral angle model is analyzed and improved. The approach of azimuthal feature extraction is proposed based on the conclusion of the improved dihedral angle model. The problems, which appear when the common change detection methods are used to extract the change feature based on ROI, are analyzed. And a robust and feasible extraction approach is presented.

分析了适于高频SAR图像的幅度特征及其提取方法用于UWB SAR图像时的有效性，提出了基于目标轮廓的幅度特征提取方法及相应的适用幅度特征；分析了已有二面角模型在建模过程中存在的问题并进行了改进建模，基于改进二面角模型结论提出了方位向特征提取方法；分析了常用变化检测方法用于提取ROI变化特征时存在的问题，提出了一种稳健可行的变化特征提取方法。

Some SAR image eigenspaces are constructed for different aspects based on independent component analysis. An independent neural network is trained for each of eigenspace of different aspects. The trained neural networks are used to recognize SAR targets, and their results are combined through D-S evidence reasoning.

通过独立分量分析构造若干个方位角的SAR图像特征空间，为每一特征空间各训练一个模糊极小极大神经网络用于分类，然后利用D-S证据理论集成各个神经网络的输出。

The People's Republic of China, excluding Hong Kong SAR, Macau SAR and Taiwan.

指中华人民共和国，但不包括香港特别行政区、澳门特别行政区和台湾。

We have limited budget let me know if you can do this competitively.

我们有限的预算让我知道如果你能做到这一点竞争力。

We don't know how other critters breathe--lizards, for example.

我们还不知道诸如蜥蜴之类的动物如何呼吸。