Distributed sensor networks (DSN) within the DoD are motivated by a need for pervasive and persistent military surveillance, as addressed in Navy DoD guidance documents. Previous studies have sought to characterize DSNs based on various attributes, taxonomies, and design spaces from more of a theoretical perspective. This paper differs from previous studies by focusing on the establishment and use of measurable, orthogonal, design-level, discriminating attributes (discriminators) for classifying DSNs. DoD and non-DoD applications are then characterized in light of these discriminators. Senior Navy/DoD leadership and other decision makers interested in understanding the characterization of DSNs within the DoD, will find this paper valuable.

关键词：无线通信；探测器；网络；分布式传感器

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Functionalized graphene-polyvinylidene fluoride (f-G-PVDF) nanocomposite films were synthesized using simple solvent casting technique. The investigation demonstrates the real time strain response of f-G-PVDF nanocomposite on macro scale under tensile loads and the use of this nanocomposite as 10 strain sensor. This is ascribed to the variation in electrical properties of graphene in the polymer upon mechanical deformation at the nanoscale.

关键词：传感器；探测器；应变计；热塑性复合材料；应变计，热塑性复合材料;探测器;电影，石墨烯，纳米技术

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Errors in the estimated constituent concentrations in optically complex waters due solely to sensor noise in a spaceborne hyperspectral sensor can be as high as 80. The goal of this work is to elucidate the effect of signal-to-noise ratio (SNR) on the accuracy of retrieved constituent concentrations. Large variations in the magnitude and spectral shape of the reflectances from coastal waters complicate the impact of SNR on the accuracy of estimation. Due to the low reflectance of water, the actual SNR encountered for a water target is usually quite lower than the prescribed SNR. The low SNR can be a significant source of error in the estimated constituent concentrations. Simulated and measured at-surface reflectances were used in this study. A radiative transfer code, Tafkaa, was used to propagate the at- surface reflectances up and down through the atmosphere. A sensor noise model based on that of the spaceborne hyperspectral sensor HICO was applied to the at- sensor radiances. Concentrations of chlorophyll-a, colored dissolved organic matter, and total suspended solids were estimated using an optimized error minimization approach and a few semi-analytical algorithms. Improving the SNR by reasonably modifying the sensor design can reduce estimation uncertainties by 10or more.

关键词：传感器；探测器；高光谱图像；信噪比；辐射传输

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The National Telecommunications and Information Administration (NTIA), in coordination with the Federal Communications Commission (FCC) and federal agencies, has established a Spectrum Sharing Innovation Test-Bed pilot program to examine the feasibility of increased sharing between federal and non-federal users. The pilot program is evaluating the ability of dynamic spectrum access (DSA) devices employing spectrum sensing and/or geo-location technologies to share spectrum with land mobile radio (LMR) systems operating in the 410-420 MHz Federal band and in the 470-512 MHz non-Federal band. Since NTIA published the Test-Bed Phase I test plan on its website in February 2009, it has been engaged in testing DSA devices at its laboratory, the Institute for Telecommunications Sciences (ITS), in Boulder, CO. The Phase I tests assess the performance and behavior of DSA devices in response to simulated LMR environment signals within a laboratory setting. The Phase I test plan document provided a notional definition of subsequent Phase II and III field testing. Phase II will assess the spectrum sensing capabilities of DSA devices in a live LMR environment with sufficient DSA transmitter attenuation to prevent interference to LMR systems. In Phase III, the DSA devices transmitter attenuation will be removed and the devices will be allowed to operate freely in a variety of live LMR radiofrequency signal environments.

关键词：无线通信；频谱；无线电系统；频率分配；频谱感知

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The increased use of Wireless Sensor Networks (WSN) for geolocation has led to an increased reliance on this technology. Jamming, protecting jamming, and detecting jamming in a WSN are areas of study that have greatly increased in interest. This research uses simulations and data collected from hardware experiments to test the effects of jamming on a WSN. Hardware jamming was tested using a Universal Software Radio Peripheral (USRP) Version 2 to assess the effects of jamming on a cooperative network of Java Sun SPOTs. The research combines simulations and data collected from the hardware experiments to see the effects of jamming on cooperative and noncooperative geolocation.

关键词：多传感器；无线电信号；无线电接收器；信号处理；位置查找

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A measurement system based on the magneto-resistive sensor is described and its error factors and influences are analyzed as well.A reasonable and simple approach is presented to compensate the measurement error from Magneto-resistive Sensor output.Firstly,the principle of the new method is illustrated.Secondly,the steps of the error compensation are introduced.Finally,the test is carried out,results are shown that the maximum angle value of deviation is no more than 2° and compensation method can be used in common measurement system based on magneto-resistive sensors.

关键词：磁阻传感器；误差补偿；电磁罗盘

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Soil humidity is considered as one of important soil parameters and is already used widely in agriculture information system.The measurement of the soil humidity,characterized by accuracy and continuity,can help build useful information systems for modem agriculture.Remote detection of soil humidity can be achieved easily by using wireless sensors network (WSN).In this paper,a way to build an automatic irrigating system taking advantage of humidity measurements,which is obtained based on Wireless Sensor Network,is proposed.That how the humidity is detected and how the WSN is constructed is discussed.Furthermore,the connection of hardware devices and theprograms of software is described.

关键词：无线传感器网络；农业；自动灌溉；土壤湿度

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A micro inductance sensor model based on the software of Maxwell to detect the debris in oil is presented.The model is built to study the detecting performance of sensors with different turns and enwinding styles.It can be demonstrated that the planar coil with 15 turns has a better sensitivity to detecting metal debris with about 100 micro meters in size.The solenoid coil with 20 turns has a better performance to detect the micro metal debris.This simulation shows that the detecting performance of a sensor is related to its parameters such as the size,turns,style of enwinding.The optimization of coils for the detection of metal debris with 100 μm in size is presented at last.

关键词：传感器；微型电感线圈；金属碎片；碎片检测

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In this paper an electronic voltage-current voltage transformer (EVCVT) scheme has been proposed based on voltage-current transformation,using the voltage-current transformation technology and weak current detection technology to achieve the accurate measurement of the grid voltage.It transforms the high voltage into low current by high voltage thick film resistor,then the current sensor transforms the low current signal into a standard analog voltage signal,thus an AD converter collects the voltage signal,and the value be imported into the microprocessor for filtration,calibration,coding.After filtering the data would be transmitted to the upper computer or relay protection devices of the digital substation.This paper focused on the design of hardware circuit of digital voltage transformer,developed the software package and produced a prototype control board.Initial experiments show that the scheme is valuable for digital substation.

关键词：电压互感器;；周电流传感器；电压 - 电流转换；周电流检测

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One important issue in sensor networks that has received renewed interest recently is average consensus, i.e., computing the average of n sensor measurements, where nodes iteratively exchange data with their neighbors and update their own data accordingly until reaching convergence to the right parameters estimate. In this paper, we introduce an efficient self-stabilizing algorithm to achieve/ensure the convergence of node states to the average of the initial measurements of the network. We prove that the convergence of the fusion process is finite and express an upper bound of the actual number of moves/iterations required by the algorithm. This means that our algorithm is guaranteed to reach a stable situation where no load will be sent from one sensor node to another. We also prove that the load difference between any two sensor nodes in the network is withinε/D ×[D+1/2] <ε, where e is the prescribed global equilibrium threshold (this threshold is given by the system) and D is the diameter of the network.

关键词：分布式传感器网络；算法；融合

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