Atmospheric structure, transhorizon propagation, and their relationship to remote sensing

Previous papers suggest that the characteristics of atmospheric structure cannot be inferred unambiguously from transhorizon scatter measurements. It is shown that the form of the refractivity spectrum can be correctly inferred from appropriate beam-swinging measurements. One analysis includes contributions from both scattered and partially reflected components of the transhorizon signal, and shows how the characteristics of the angular response pattern of the received signal varies with changes in these components. Analytically derived patterns are compared with measured response patterns. The form of the refractivity spectrum inferred from the comparison is consistent with the form suggested from physical arguments and by the results of independent transhorizon experiments. Because the transhorizon signal includes scattered and partially reflected signals, remote-sensing techniques using transhorizon methods should employ both signal components to correctly derive atmospheric parameters. Finally, both of these signal components should be used for channel models that use adaptive algorithms to optimize the design of troposcatter communication networks.     

端元匹配的遥感影像地物自适应光谱表征

光谱信息是遥感识别地物的依据,而目前已发展的典型地类的光谱指数模型有限,波谱库中的标准地物类型及其普适性也是有限的.鉴于此,提出一种端元匹配的地物自适应光谱表征方法,通过选取贴合影像本身的端元,并综合光谱角和距离度量对影像和端元光谱进行综合匹配.通过ETM+(Enhanced Thematic Mapper)影像上对植被、水体与美国地质调查局(United States Geological Survey,USGS)波谱库及归一化植被/水体指数的对比实验,及阴影、裸地等的验证实验,证实了该方法的有效性和普适性.     

Separating touching objects in remote sensing imagery: therestricted growing concept and implementations

This paper defines the restricted growing concept (RGC) fur object separation and provides an algorithmic analysis of its implementations. Our concept decomposes the problem of object separation into two stages. First, separation is achieved by shrinking the objects to their cores while keeping track of their originals as masks. Then the core is grown within the masks obeying the guidelines of a restricted growing algorithm. In this paper, we apply RGC to the remote sensing domain, particularly the synthetic aperture radar (SAR) sea ice images.     

基于GIS和遥感技术的青白江生态功能区划定

近年来生态系统的保护受到广泛关注。本文主要基于GIS和遥感技术宏观快速的优点,将生态系统服务功能评估技术应用于生态功能区划定。通过分析青白江区内各种生态系统的生物多样性维护、水源涵养功能的评估结果,划定青白江区重要生态功能区。     

遥感卫星接收系统伺服监控软件设计

伺服系统是遥感卫星地面接收系统的重要组成部分,可靠性和安全性要求高。采用单进程、多线程、并行多模块的结构,设计伺服系统监控软件,实现了天线控制、设备监视、信息显示、数据处理、通信及伺服性能指标自动化测试等功能,具有实时性强,自动化程度高,容错性、可靠性及扩展性好等特点。该设计已用于实际工程项目中,实际使用结果表明该设计是合理可行的。     

Multiple kernel relevance vector machine for geospatial objects detection in high-resolution remote sensing images

Geospatial objects detection within complex environment is a challenging problem in remote sensing area. In this paper, we derive an extension of the Relevance Vector Machine (RVM) technique to multiple kernel version. The proposed method learns an optimal kernel combination and the associated classifier simultaneously. Two feature types are extracted from images, forming basis kernels. Then these basis kernels are weighted combined and resulted the composite kernel exploits interesting points and appearance information of objects simultaneously. Weights and the detection model are finally learnt by a new algorithm. Experimental results show that the proposed method improve detection accuracy to above 88%, yields good interpretation for the selected subset of features and appears sparser than traditional single-kernel RVMs.     

关于遥感图像的水质监测评价系统设计

本文通过关于遥感图像的水质监测评价系统（RWQMES）的设计,实现了水质遥感图像的分析、处理,水质的预测、评价三部分功能的统一管理。为水污染防治、水资源可持续开发利用及水资源管理的规范化和科学化,提供了有效的信息技术支持。     

Hidden Markov models applied to vegetation dynamics analysis usingsatellite remote sensing

Details hidden Markov models (HMM) with respect to their ability to represent time series of remotely sensed data as well as to analyze vegetation dynamics at large scales. The present approach is shown to be a powerful way to classify and extract various dynamics parameters as well as to detect phenological anomalies. The methodology is applied and validated using the Advanced Very High Resolution Radiometer (AVHRR) normalized difference vegetation index (NDVI) time series. The model is then used to determine vegetation active cycle and the length of the growing season in the West African savanna     

卫星遥感与6G通信遥感一体化

卫星遥感是人类实现高分辨率对地观测的重要手段,已逐步成为支撑经济社会发展以及国防安全的重要组成。6G追求通信遥感计算深度融合,通信遥感一体化成为其重要的特征。回顾了国内外卫星遥感的发展历程,概述了卫星遥感系统现有的体系结构和6G时代通信遥感一体化体系架构,阐述了人工智能驱动的典型卫星遥感技术和最新研究进展。针对6G时代卫星通信遥感一体化的趋势,探讨了实现“一星多用、多星组网、多网融合、智能服务”组合型发展的技术挑战和发展趋势。     

聚类与几何特征相结合的遥感图像多类人造目标检测算法

针对高分辨率光学遥感图像中人造目标的检测问 题,对传统的相位编组直线段提取算法和k-means 聚类算法了改进,提出了一种k-means聚类和几何特征 相结合的检测方法。根据自然物体和 人造目标在几何外形上表现出的不同特性,首先运用改进的相位编组算法对图像进行快速的 直线段提取; 然后以获取的直线段中心点为处理对象,运用k-means聚类算法 对提取的直线段进行密度聚类;最后,根 据每个类中的直线段数目和构成的几何基元情况,进行人造目标的判定。实验结果表明,本 文算法对遥感 图像中的房屋、汽车、船舰和飞机跑道等多类人造目标可达到90%以 上的检测精度,并具有较高的检测速度,对于一幅512pixel ×512pixel的图像,整个检测过程在100ms 以内。     

Accounting for the effects of widespread discrete clutter in subsurface EMI remote sensing of metallic objects

In practice, most signal processing strategies for discrimination of buried objects are clutter limited. This applies even to discrimination of shallow sizable metallic objects, such as unexploded ordnance (UXO), which are to be found predominantly in the top meter of soil. The environment typically features widespread metallic clutter from detonated ordnance or other sources. Such fragments can be numerous and are often shallower than the objects of interest. Currently, the preeminent remote sensing mode for buried UXO is ultrawideband electromagnetic induction (EMI), operating over part or all of the band from some tens of hertz up to perhaps hundreds of kilohertz. Particularly because EMI fields fall off sharply with range, signals from shallow clutter may be relatively strong and can easily obscure essential scatterer signatures. To treat this, a rational theory of EMI scattering from widespread metallic clutter is formulated and tested. For dense, well-distributed clutter, analytical rules are derived for dependence of signal strength on sensor elevation, under various fundamental excitation types. For more erratic, sparse clutter distributions, signal statistics from Monte Carlo simulations show patterns like those from the analytical rules. The dependence of clutter signal magnitude on antenna elevation is determined for both thin surface layers and for volume layers of widespread small items, and for both dense and sparse clutter distributions. These are contrasted with the patterns expected from single, larger, discrete objects of interest, and the contrast is exploited in discrimination exercises for the screening problem. For sparse clutter distributions, results from inversion processing formulations that account for the patterns of clutter statistics are compared to simple least squares treatments.     

激光雷达监测海面溢油遥感理论

超连续谱激光在保持激光原有的高能量密度和良好的方向性的基础上,还具有较宽测量谱段的特点,因此与传统的被动式遥感方式相比,超连续谱激光雷达具有很多独特的优势。在海面溢油探测领域,对溢油事故的发生进行及时而准确的监测是十分重要的,当前采用的遥感探测技术均存在各种缺陷,而超连续谱激光雷达能够在夜晚和白天持续工作,且由于探测信号为回波信号,因此能够实现较大的探测距离和较高的遥感精度。本文主要从海面溢油监测现状、大气对激光传输的影响以及海面溢油高光谱遥感原理入手,对激光雷达海面溢油遥感理论进行了介绍。     

基于无人机遥感数据的国有土地覆盖变化动态监测

传统方法对国有土地覆盖变化监测时,未对高空间特征提取,与无人机遥感数据融合效果不佳。为此,文中提出一种新的方法解决国有土地覆盖变化检测问题。通过无人机遥感技术采集国有土地覆盖图像;采用边缘轮廓特征法对国有土地覆盖无人机遥感特征进行检测,构建土地覆盖遥感图像的像素空间重构模型;依据图像区域重构遥感图像的高空间特征,通过相似度信息融合无人机遥感数据与图像高空间特征,实现国有土地覆盖变化动态监测。仿真结果表明,文中方法能够有效融合高空间特征与无人机遥感数据,国有土地覆盖变化动态监测效果较好,同时无人机遥感特征提取的精度较高,实现了国有土地覆盖变化的动态反馈。     

The military applications of remote sensing by infrared

Remote sensing is the process of acquiring information from the environment by the use of a sensor that is not in physical contact with the object under study. The military services are experienced practitioners of this old, but newly glamorous, art. Their accomplishments in the infrared, that region lying between visible light on the one hand and microwaves on the other, are both impressive and of increasing importance. Our purpose is to provide an overview of these accomplishments. We begin with a brief treatment of the characteristics and peculiarities of the infrared portion of the spectrum and of the sensors that operate there. Early military experience with remote sensing by infrared is described and an applications matrix is developed in order to provide a perspective from which the reader can view the full panorama of military applications. Specific applications ate discussed. These include strategic systems for early warning of intercontinental ballistic missile launches, methods for the detection of atmospheric contaminants, such as poison gas, under field conditions, aids for the precision delivery of weaponry (including passive, active, and laser designator guidance techniques), and sensor systems for reconnaissance and surveillance. Wherever possible, details of sensor performance are given.     

运动物体的压缩感知成像

在使用压缩感知成像系统进行成像时,物体的运动会导致获取的物体图像分辨率下降.为了克服运动的干扰需要额外装置获取物体运动的参数,但在很多情况下无法获取物体的运动速度.针对这一问题,提出利用物体运动与散斑运动的相关性,采用散斑运动方式来抵消物体运动从而消除运动造成的分辨率下降.采用压缩感知算法利用多组不同散斑运动补偿情况下的参数获取不同的物体图像,最后利用物体运动和散斑运动的相关性判据参数,最终获得消除运动干扰的物体图像。算法求解中同时考虑了系统点扩散函数的影响,采用解卷积算法获取了消除运动和系统点扩散函数影响的物体图像。最后数字仿真结果证实了所提算法的有效性。     

Far ultraviolet remote sensing of ionospheric emissions by PolarBEAR

A few thousand far-ultraviolet images of the ionosphere have been obtained since December 1986 by the Atmospheric/Ionospheric Remote Sensor (AIRS) aboard the Polar BEAR satellite. Fast algorithms for applying automated satellite-attitude, geometric, and photometric corrections to these images were developed, and the first results are discussed. A software package that is based on these algorithms was implemented and tested. Since no attitude data is available at night (one of the two gauges is a Sun sensor), an algorithm was devised to extrapolate daytime attitude corrections to nighttime. An additional method is offered to correct satellite roll from the measured or extrapolated one based on the dayglow limbs observed at the edges of the image. Geometric rectifications include transformations to the image from the satellite coordinate system to a reference system, and from the reference system to the geographic coordinate system. Radiometric corrections include image enhancement, background airglow subtraction, and off-nadir normalization of auroral emissions. The latter two are based on theoretical calculations of column emission rates, derived by radiative transfer integrations of volume emission rates along the look direction. Results include mapping of auroral arcs in the corrected geomagnetic system, the one most applicable to auroral studies     

Earth system science and remote sensing

A conceptual model is presented of the Earth System appropriate to global change on timescales of decades to centuries. This is used as a framework for discussion of the processes and feedbacks involved in the physical climate system and in biogeochemical cycles, and the expected role of remote sensing in understanding them. Demonstrated and potential opportunities for space-related observations are identified in the context of broader needs for information about the various subsystems, concluding with a brief discussion of the program needed to better understand the impact of human activities on the global environment in the context of natural variability.     

基于二维压缩感知的定向遥感和变化检测

基于高斯测量矩阵的一维压缩感知测量数据不仅能很好地保持稀疏信号的能量信息, 也能够很好地继承稀疏信号的方向信息.但是在一维压缩感知模型中方向信息无法应用于稀疏信号的重构和检验.针对遥感影像中变化区域稀疏的特点提出了二维压缩感知模型.并利用能量和方向信息构建了基于二维压缩感知的稀疏信号重构算法(2DOMP).理论分析和实验结果证明, 2DOMP算法的信号重构能力更强.同时根据压缩感知恢复稀疏信号只需要很少测量数据的特性提出了定向遥感和定向变化检测的概念.     

Multiset canonical correlations analysis and multispectral, trulymultitemporal remote sensing data

This paper describes two- and multiset canonical correlations analysis (CCA) for data fusion, multisource, multiset, or multitemporal exploratory data analysis. These techniques transform multivariate multiset data into new orthogonal variables called canonical variates (CVs) which, when applied in remote sensing, exhibit ever-decreasing similarity (as expressed by correlation measures) over sets consisting of (1) spectral variables at fixed points in time (R-mode analysis), or (2) temporal variables with fixed wavelengths (T-mode analysis). The CVs are invariant to linear and affine transformations of the original variables within sets which means, for example, that the R-mode CVs are insensitive to changes over time in offset and gain in a measuring device. In a case study, CVs are calculated from Landsat Thematic Mapper (TM) data with six spectral bands over six consecutive years. Both Rand T-mode CVs clearly exhibit the desired characteristic: they show maximum similarity for the low-order canonical variates and minimum similarity for the high-order canonical variates. These characteristics are seen both visually and in objective measures. The results from the multiset CCA R- and T-mode analyses are very different. This difference is ascribed to the noise structure in the data. The CCA methods are related to partial least squares (PLS) methods. This paper very briefly describes multiset CCA-based multiset PLS. Also, the CCA methods can be applied as multivariate extensions to empirical orthogonal functions (EOF) techniques. Multiset CCA is well-suited for inclusion in geographical information systems (GIS).