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conference on unattended/Unmanned ground, Ocean and Air sensor technologies and applications VI

作者： Drummond, AP Nova Engn Inc Cincinnati OH 45246 USA

ISBN: (纸本)0819453404

Requirements in unattended ground sensor (UGS) systems have grown to include data privacy, message authentication. and anti-spoofing measures. This presents a challenge to the systems architect to consider approaches that defend against known and unknown attacks designed to compromise the system integrity. Encryption has been the preferred method to address these requirements. Encryption may be used to increase our confidence in the data transmitted in sensor networks, but requires greater, not less, attention to system security. After all, in an unencrypted network, at least we "know" that an adversary can read our data.

关键词： encryption spoofing authentication key management security

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Digital optical tags for unattended ground sensor applications

Digital optical tags for unattended ground sensor applicatio...

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conference on unattended ground sensor technologies and applications VII

作者： Griggs, SP Mark, MB Feldman, BJ Def Adv Res Projects Agcy Arlington VA 22203 USA

ISBN: (纸本)0819457817

DARPA Dynamic Optical Tags (DOTS) program has as its goal the development of a low cost, small, robust, persistent, low probability of intercept, 2-way tagging, tracking, and locating device that also supports error free data rates in excess of 100 kbps and can be interrogated at ranges up to and beyond 1Km. The program has selected several promising candidates for this device and is in the process of evaluating individually their performance against predetermined milestones to ascertain whether the technology is feasible and the program should continue for further development. In all cases the candidate devices operate as retro-reflecting optical modulators. Upon interrogation by a laser at the correct wavelength and with the correct code, the tags will proceed to modulate the return retro-reflection. While data for the candidate devices are not yet in hand, nevertheless this paper will provide an overview of the nature of the devices under investigation and speculate on how these devices could be employed for unattended ground sensor applications.

关键词： retro-reflecting modulators optical modulators tagging systems tracking systems

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Acoustic and seismic modalities for unattended ground sensors

Acoustic and seismic modalities for unattended ground sensor...

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conference on unattended ground sensor technologies and applications

作者： Sleefe, GE Ladd, MD McDonald, TS Elbring, GJ Sandia Natl Labs Albuquerque NM 87185 USA

ISBN: (纸本)0819431877

The use of acoustic and seismic modalities in unattended ground sensor systems has been an active area of research. However, a thorough study of the advantages and complementary aspects of the two modalities has not heretofore been considered. This paper provides a detailed description of both acoustic and seismic methods for unattended ground sensors. We discuss acoustic and seismic phenomenology;source mechanisms, propagation paths, attenuation, and sensing. These phenomena significantly impact the detection, identification, and localization objectives of unattended ground sensors. As such, certain applications will benefit from exploiting acoustic ground sensing, seismic ground sensing, or in some cases, both. A methodology is presented for selecting the preferred modality (acoustic and/or seismic) for a particular application. It is shown that the preferred modality significantly impacts the architecture of the ground sensor system. Important system architecture criteria such as transducer selection, data acquisition bandwidth, array geometry, and communications requirements are considered in this paper. Furthermore, the effects of seismo-acoustic and acousto-seismic interactions are addressed. It is shown that acoustic transducers may respond to seismic excitation, and seismic transducers often respond to acoustic excitation. In some instances, this dual-modality is of benefit. We also provide recommendations for minimizing seismic/acoustic cross talk for applications requiring independent seismic or acoustic modes.

关键词： acoustic seismic sensor phenomenology unattended

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Error mechanisms in determining timing errors in unattended ground sensors

Error mechanisms in determining timing errors in unattended ...

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conference on unattended ground sensor technologies and applications VII

作者： Beale, DAR Hume, AL Calloway, VP QinetiQ Malvern WR14 3PS Worcs England

ISBN: (纸本)0819457817

The cost of an unattended ground sensor system is based on two factors: the number of sensor nodes used and, the complexity of each sensor / communications node. The tracking accuracy of the sensor network is a trade off between the density of the network and the accuracy with which the sensor nodes can determine the position or bearing of the target. Assuming acoustic sensors, the errors reduce, primarily, to timing errors, within each of the sensor nodes. Therefore that understanding the timing errors within a network of acoustic nodes is a factor in determining system cost for a given level of information fidelity. This paper explores the error mechanisms within and without each of the sensor nodes thus identifying the critical sub systems where engineering effort would be most effectively directed.

关键词： netted sensors UGS disposable acoustic error analyses

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unattended wireless proximity sensor networks for Counter-Terrorism, Force Protection, littoral environments, PHM & tamper monitoring ground applications

Unattended wireless proximity sensor networks for Counter-Te...

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conference on unattended ground sensor technologies and applications V

作者： Forcier, B BeezerBug Inc Mesa AZ 85213 USA

ISBN: (纸本)0819449504

This paper describes a digital-ultrasonic ground network, which forms an unique "unattended mote sensor system" for monitoring the environment, personnel, facilities, vehicles, power generation systems or aircraft in Counter-Terrorism, Force Protection, Prognostic Health Monitoring (PHM) and other ground applications. unattended wireless smart sensor/tags continuously monitor the environment and provide alerts upon changes or disruptions to the environment. These wireless smart sensor/tags are networked utilizing ultrasonic wireless motes, hybrid RF/Ultrasonic Network Nodes and Base Stations. The network is monitored continuously with a 24/7 remote and secure monitoring system. This system utilizes physical objects such as a vehicle's structure or a building to provide the media for two way secure communication of key metrics and sensor data and eliminates the "blind spots" that are common in RF solutions because of structural elements of buildings, etc. The digital-ultrasonic sensors have networking capability and a 32-bit identifier, which provide a platform for a robust data acquisition (DAQ) for a large amount of sensors. In addition, the network applies a unique "signature" of the environment by comparing sensor-to-sensor data to pick up on minute changes, which would signal an invasion of unknown elements or signal a potential tampering in equipment or facilities. The system accommodates satellite and other secure network uplinks in either RF or UWB protocols. The wireless sensors can be dispersed by ground or air maneuvers. In addition, the sensors can be incorporated into the structure or surfaces of vehicles, buildings, or clothing of field personnel.

关键词： unattended ground sensors motes wireless homeland security

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Highly sensitive ruggedized fiber optic vibrometer for unattended ground sensor

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Proceedings of SPIE - The International Society for Optical Engineering 1999年 3713卷 33-42页

作者： Shnitser, P.I. Agurok, I.P. Avakian, A. Physical Optics Corp Torrance United States

Vibration sensors provide very important information for an unattended ground sensor network. For this specific application, a vibration sensor must be extremely robust and must have very high sensitivity and very low power consumption. The authors experimentally demonstrated two schemes of fiber optic interferometric sensors capable of sensing vibrations with amplitudes of a few tens of picometers in the frequency range below 1 kHz. The proposed schemes consist of commercially available components and make possible fabrication of a ruggedized, highly sensitive sensor with low power consumption.

关键词： Remote sensing

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Pearls of Wisdom wireless networks of miniaturized sensors

Pearls of Wisdom wireless networks of miniaturized sensors

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conference on unattended ground, Sea, and Air sensor technologies and applications XIV

作者： Rippin, B. Pearls Wisdom Adv Technol IL-40593 Kfar Netter Israel

ISBN: (纸本)9780819490667

Pearls of Wisdom has been working on the development of sensing systems for unattended ground applications using miniaturized elements. Our vision is to enable various monitoring applications using the deployment of a large number of low cost miniature wireless sensors. The operation of sensors of multiple modalities working in harmony, together with the ability to integrate the measurements and turn them into coherent information provides an opportunity for new applications and improved performance. The development of such systems is based on three pillars of excellence: a wireless network foundation which is low bandwidth, yet flexible enough to support the needs of different applications, ultra-low-power design of sensors and a data analysis system

关键词： Pearls of Wisdom micro unattended ground sensors persistent surveillance networked sensors ultra-low power design

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iScout™ low cost ad-hoc networked sensor enhancements

iScout™ low cost ad-hoc networked sensor enhancements

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conference on unattended ground, Sea, and Air sensor technologies and applications IX

作者： Winston, Mark A. McQ Inc Fredericksburg VA 22405 USA

ISBN: (纸本)9780819466846

McQ has developed a family of state of the art miniaturized low cost unattended ground sensors (UGS). The iScout (TM) sensors are designed for indoor and outdoor intrusion detection and battle damage assessment. McQ has developed an enhanced version of the iScout (TM) sensor that is a very flexible platform capable of performing in a variety of applications. sensors are equipped with mesh radios and integrated seismic. acoustic. infrared, and magnetic transducers. Typical sensor sizes are similar to that of a deck of playing cards. Intended for high volume production, these are tactically useful sensors that can be manufactured in high volumes at a low cost. This paper will provide an overview of the iScout (TM) sensor systems, features, and performance.

关键词： low cost small ad-hoc mesh unattended ground sensor wireless sensor network urban surveillance

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Fractional-N synthesizer simplifies UHF sensor radio

Fractional-N synthesizer simplifies UHF sensor radio

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conference on unattended/Unmanned ground, Ocean and Air sensor technologies and applications VI

作者： Alaimo, L Nova Engn Cincinnati OH 45246 USA

ISBN: (纸本)0819453404

Low power and small size are key features of the radio hardware associated with unattended ground sensors (UGS). The RF modulation capability of the radio is an important parameter that affects overall network performance, and drives the size, cost and power consumption of both receive and transmit circuitry. This paper describes the use of a fractional-N synthesizer to directly generate various modulation waveforms at the transmit frequency. A design example is presented to highlight the benefits of this technique on a typical UHF sensor radio.

关键词： Modulation sensors Phase shift keying Frequency shift keying Frequency modulation unattended ground sensors Phase modulation Fast packet switching Modulators Phase shifts

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Acoustic and seismic modalities for unattended ground sensors

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Proceedings of SPIE - The International Society for Optical Engineering 1999年 3713卷 2-9页

作者： Sleefe, Gerard E. Ladd, Mark D. McDonald, Timothy S. Elbring, Gregory J. Sandia Natl Lab Albuquerque United States

The use of acoustic and seismic modalities in unattended ground sensor systems has been an active area of research. However, a thorough study of the advantages and complementary aspects of the two modalities has not heretofore been considered. This paper provides a detailed description of both acoustic and seismic methods for unattended ground sensors. We discuss acoustic and seismic phenomenology; source mechanisms, propagation paths, attenuation, and sensing. These phenomena significantly impact the detection, identification, and localization objectives of unattended ground sensors. As such, certain applications will benefit from exploiting acoustic ground sensing, seismic ground sensing, or in some cases, both. A methodology is presented for selecting the preferred modality (acoustic and/or seismic) for a particular application. It is shown that the preferred modality significantly impacts the architecture of the ground sensor system. Important system architecture criteria such as transducer selection, data acquisition bandwidth, array geometry, and communications requirements are considered in this paper. Furthermore, the effects of seismo-acoustic and acousto-seismic interactions are addressed. It is shown that acoustic transducers may respond to seismic excitation, and seismic transducers often respond to acoustic excitation. In some instances, this dual-modality is of benefit. We also provide recommendations for minimizing seismic/acoustic cross talk for applications requiring independent seismic or acoustic modes.

关键词： Remote sensing

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