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Highly Efficient Fluorescence Detection In Picoliter Volume Liquid-Core Waveguides, Aaron R. Hawkins, John P. Barber, Dongliang Yin Nov 2005

Highly Efficient Fluorescence Detection In Picoliter Volume Liquid-Core Waveguides, Aaron R. Hawkins, John P. Barber, Dongliang Yin

Faculty Publications

We report loss improvement and fluorescence detection in integrated antiresonant reflecting optical waveguides with liquid cores. The minimum waveguide loss is reduced to 0.33/cm by compensating for thickness variations in the fabrication process. We demonstrate fluorescence detection from as few as 490 molecules in a 57 pl core using these optimized waveguides. We measure angular fluorescence collection factors as high as 15% per facet in good agreement with theory. This demonstrates the potential of integrated hollow-core waveguides as optical sensors for single-molecule spectroscopy.

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Array Analysis Of Radio Frequency Interference Cancelation Requirements For A Land Mine Detection System, Devin Baker Pratt Nov 2005

Array Analysis Of Radio Frequency Interference Cancelation Requirements For A Land Mine Detection System, Devin Baker Pratt

Theses and Dissertations

Land mines are a major humanitarian problem with millions of active mines in place around the world. Since these mines can have little metal in them, novel detection techniques are needed. Nuclear Quadrupole Resonance (NQR) is one such technique. Unfortunately, NQR is highly succeptible to radio frequency interference (RFI). A significant contribution of this thesis is the development of a custom, experimental data acquisition system designed and built specifically for capturing RFI at frequencies significant to NQR land mine detection systems. Another major contribution is the development of data analysis techniques for determining the number of reference antennas required to …

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Using Ultrasonic Atomization To Produce An Aerosol Of Micron-Scale Particles, Thomas D. Donnelly, J. Hogan '03, A. Mugler '04, M. Schubmehl '02, N. Schommer '04, Andrew J. Bernoff, S. Dasnurkar, T. Ditmire Nov 2005

Using Ultrasonic Atomization To Produce An Aerosol Of Micron-Scale Particles, Thomas D. Donnelly, J. Hogan '03, A. Mugler '04, M. Schubmehl '02, N. Schommer '04, Andrew J. Bernoff, S. Dasnurkar, T. Ditmire

All HMC Faculty Publications and Research

A device that uses ultrasonic atomization of a liquid to produce an aerosol of micron-scale droplets is described. This device represents a new approach to producing targets relevant to laser-driven fusion studies, and to rare studies of nonlinear optics in which wavelength-scale targets are irradiated. The device has also made possible tests of fluid dynamics models in a novel phase space. The distribution of droplet sizes produced by the device and the threshold power required for droplet production are shown to follow scaling laws predicted by fluid dynamics.

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H-Infinity Estimation For Fuzzy Membership Function Optimization, Daniel J. Simon Nov 2005

H-Infinity Estimation For Fuzzy Membership Function Optimization, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Given a fuzzy logic system, how can we determine the membership functions that will result in the best performance? If we constrain the membership functions to a specific shape (e.g., triangles or trapezoids) then each membership function can be parameterized by a few variables and the membership optimization problem can be reduced to a parameter optimization problem. The parameter optimization problem can then be formulated as a nonlinear filtering problem. In this paper we solve the nonlinear filtering problem using H∞ state estimation theory. However, the membership functions that result from this approach are not (in general) sum normal. …

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Social Utility Functions-Part I: Theory, Wynn C. Stirling Nov 2005

Social Utility Functions-Part I: Theory, Wynn C. Stirling

Faculty Publications

The dominant approaches to utility-based multiagent decision theory rely on the premise of individual rationality-the doctrine that each individual is committed to achieving the best outcome for itself, regardless of the effect doing so has on others. This fundamentally asocial concept is the basis of conventional von Neumann-Morgenstern (vN-M) utilities but is inadequate to characterize truly cooperative artificial systems. Social utility functions differ from conventional vN-M utilities in that they are functions of multiple decision-maker preferences, rather than actions, and thus permit individuals to expand their spheres of interest beyond the self. A logical basis for coherent reasoning in multiagent …

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Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal, B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal Oct 2005

Terahertz Studies Of The Dielectric Response And Second-Order Phonons In A Gase Crystal, B. L. Yu, F. Zeng, V. Kartazayev, R. R. Alfano, K. C. Mandal

Faculty Publications

No abstract provided.

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A Patterning Process Utilizing A Nanoimprint Lithography For Fabrication Of Planar Perpendicular Patterned Magnetic Media, Robert Grove Iii Oct 2005

A Patterning Process Utilizing A Nanoimprint Lithography For Fabrication Of Planar Perpendicular Patterned Magnetic Media, Robert Grove Iii

Theses and Dissertations

This thesis describes the results of applied research in the area of patterned magnetic media. Current magnetic media is pushing the physical limits of magnetic bits by compressing them into very small spaces - a process that will eventually be hampered by the superparamagnetic effect. The superparamagnetic effect will require the magnetic media industry to find a modified method of storing magnetic bits. Perpendicular patterned magnetic media could be the method of choice for future generations of magnetic data storage. Patterning magnetic media allows bits to be stored in isolated magnetic islands instead of in a continuous magnetic surface, as …

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Magneto-Photonic Crystal Isolators, Miguel Levy Oct 2005

Magneto-Photonic Crystal Isolators, Miguel Levy

Michigan Tech Patents

A magneto-optical isolator (20) for an optical circuit. The isolator includes a substrate, and an optical channel (350) disposed next to the substrate. The optical channel and substrate are configured to transmit optical radiation within the optical channel. The isolator further includes a photonic- crystal rotator (24) formed with the substrate and the optical channel. The rotator has at least one defect (52) and magnetic (M) and non-magnetic (N) materials.

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Design And Development Of Poly -(3 -Hexylthiophene) Field Effect Transistors, Fengliang Xue Oct 2005

Design And Development Of Poly -(3 -Hexylthiophene) Field Effect Transistors, Fengliang Xue

Doctoral Dissertations

Organic field effect transistors (OFETs) with poly(3-hexylthiophene) (P3HT) as the active layer are developed and studied. The device characteristics are significantly affected by source/drain contact resistance, and P3HT-SiO 2 interface and the traps. These results are verified by the numerical device simulations. The temperature dependence of device mobility is studied, which indicates that the carrier transport is either heat-assisted or heat-limited at different temperature ranges. The on/off ratio and threshold voltage are found to be dependent on the temperature. Hysteresis effect due to gate electric stress is investigated. The silanol groups present at the SiO2 surface are thought to be …

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Performance Evaluation Of Video Streaming With Background Traffic Over Ieee 802.11 Wlan Networks, Nicola Cranley, Mark Davis Oct 2005

Performance Evaluation Of Video Streaming With Background Traffic Over Ieee 802.11 Wlan Networks, Nicola Cranley, Mark Davis

Conference papers

There is an increasing demand for multimedia streaming applications over WLAN networks. MPEG-4 and H.264 are compression standards targeted at high-quality streamed multimedia services over wireless best-effort IP networks. However, the dynamic nature of wireless networks in terms of fluctuating bandwidth and time-varying delays makes it difficult to provide good quality streaming under such constraints. Multimedia streaming applications are a demanding and challenging service to deliver over wireless networks. There is a trade-off between the capacity of the wireless network and the quality of the multimedia streaming application. In this paper we investigate the effect the background traffic load has …

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Dynamic Voltage Scaling Techniques For Power Efficient Video Decoding, Ben Lee, Eriko Nurvitadhi, Reshma Dixit, Chansu Yu, Myungchul Kim Oct 2005

Dynamic Voltage Scaling Techniques For Power Efficient Video Decoding, Ben Lee, Eriko Nurvitadhi, Reshma Dixit, Chansu Yu, Myungchul Kim

Electrical and Computer Engineering Faculty Publications

This paper presents a comparison of power-aware video decoding techniques that utilize dynamic voltage scaling (DVS). These techniques reduce the power consumption of a processor by exploiting high frame variability within a video stream. This is done through scaling of the voltage and frequency of the processor during the video decoding process. However, DVS causes frame deadline misses due to inaccuracies in decoding time predictions and granularity of processor settings used. Four techniques were simulated and compared in terms of power consumption, accuracy, and deadline misses. In addition, this paper proposes the frame-data computation aware (FDCA) technique, which is …

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Fourier Transform Analysis Of Terahertz Radiation, Chikaodira N. Okpo Oct 2005

Fourier Transform Analysis Of Terahertz Radiation, Chikaodira N. Okpo

Electrical & Computer Engineering Theses & Dissertations

Advances in terahertz radiation (T-rays) technology have great promise in various technological areas ranging from medical technology, imaging technology and accelerator technology. At Thomas Jefferson Laboratory, the Free Electron Laser division (FEL) produces very powerful beam of laser light by accelerating electrons in bunches along a beamline. This laser light absorbs and releases energy at various wavelengths. The new FEL upgrade led to the production of very bright terahertz (THz) radiation with an average power of 1 00watts which is about 100,000 times brighter than those produced elsewhere. These T-rays have very significant applications in the Laboratory. The most significant …

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Evaluation Of Microwave Reflection Properties Of Cyclically Soaked Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, K. E. Kurtis, R. Zoughi Oct 2005

Evaluation Of Microwave Reflection Properties Of Cyclically Soaked Mortar Based On A Semiempirical Electromagnetic Model, Shanup Peer, K. E. Kurtis, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Detection of chloride ingress and evaluation of its distribution and temporal movement in reinforced concrete structures is an important practical issue. Steel reinforcing bars embedded in good quality concrete are normally protected from corrosion. However, the presence of a sufficient concentration of free chloride ions in the region of the reinforcing steel can initiate the process of corrosion. Therefore, it is important to be able to detect ingress of chloride ions and their distribution in cement-based materials. Moreover, it is important to obtain this information nondestructively. In recent years, near-field microwave nondestructive evaluation methods, using open-ended rectangular waveguide probes, have …

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Complex Power Distribution Network Investigation Using Spice Based Extraction From First Principle Formulations, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault, Stefano Grivet-Talocia, Flavio G. Canavero Oct 2005

Complex Power Distribution Network Investigation Using Spice Based Extraction From First Principle Formulations, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault, Stefano Grivet-Talocia, Flavio G. Canavero

Electrical and Computer Engineering Faculty Research & Creative Works

The modeling and the analysis of the power distribution networks (PDN) within multi-layer printed circuit board is crucial for the investigation of the performance of PCB systems. Carrying out such analyses in SPICE based tools has the advantage of being faster than the corresponding full-wave modeling and it allows obtaining both frequency and time domain results.

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Qca-Based Majority Gate Design Under Radius Of Effect-Induced Faults, Zachary D. Patitz, Nohpill Park, Minsu Choi, Fred J. Meyer Oct 2005

Qca-Based Majority Gate Design Under Radius Of Effect-Induced Faults, Zachary D. Patitz, Nohpill Park, Minsu Choi, Fred J. Meyer

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents reliable QCA cell structures for designing single clock-controlled majority gates with a tolerance to radius of effect-induced faults, for use as a basic building component for carry look-ahead adder. Realizable quantum computing is still well in the future due to the complexity of the quantum mechanics that govern them. In this regard, QCA-based system design is a challenging task since each cell''s state must interact with all the cells that are in its energy-effective range in its clocking zone, referred to as its radius of effect. This paper proposes a design approach for majority gates to overcome …

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Machine Design Considerations For The Future Energy Challenge, Jonathan W. Kimball, Marco Amrhein Oct 2005

Machine Design Considerations For The Future Energy Challenge, Jonathan W. Kimball, Marco Amrhein

Electrical and Computer Engineering Faculty Research & Creative Works

Motors consume a significant fraction of electricity in the United States and in the world. As part of the International Future Energy Challenge, student teams are endeavoring to improve the efficiency of fractional-horsepower machines. The present work summarizes the motor design and construction process for a 500 W prototype induction machine targeting efficiency above 80%. Analytical and finite-element results are shown.

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Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical Deliverables, Andrew Lee, Art Maccarley Sep 2005

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical Deliverables, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

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Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Analysis Of Driver Response To Caws Warning Messages, Andrew Lee, Art Maccarley Sep 2005

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Analysis Of Driver Response To Caws Warning Messages, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

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Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical And Operational Assessment, Andrew Lee, Art Maccarley Sep 2005

Instrumentation And Evaluation Of District 10 Caltrans Automated Warning System (Caws): Technical And Operational Assessment, Andrew Lee, Art Maccarley

Electrical Engineering

No abstract provided.

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The Human Eye Position Control System In A Rehabilitation Setting, Yvonne Nolan, Ted Burke, C. Boylan, Annraoi De Paor Sep 2005

The Human Eye Position Control System In A Rehabilitation Setting, Yvonne Nolan, Ted Burke, C. Boylan, Annraoi De Paor

Articles

Our work at Ireland’s National Rehabilitation Hospital involves designing communication systems for people suffering from profound physical disabilities. One such system uses the electro-oculogram, which is an (x,y) system of voltages picked up by pairs of electrodes placed, respectively, above and below and on either side of the eyes. The eyeball has a dc polarisation between cornea and back, arising from the photoreceptor rods and cones in the retina. As the eye rotates, the varying voltages projected onto the electrodes drive a cursor over a mimic keyboard on a computer screen. Symbols are selected with a switching action derived, for …

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Nonlinear Regression Methods For Estimation, Eric B. Nelson Sep 2005

Nonlinear Regression Methods For Estimation, Eric B. Nelson

Theses and Dissertations

Regression techniques are developed for batch estimation and applied to three specific areas, namely, ballistic trajectory launch point estimation, adaptive flight control, and radio-frequency target triangulation. Specifically, linear regression with an intercept is considered in detail. An augmentation formulation is developed. Extensions of theory are applied to nonlinear regression as well. The intercept parameter estimate within the linear regression is used to identify the effects of trim change that are associated with the occurrence of a control surface failure. These estimates are used to adjust the inner loop control gains via a feed-forward command, hence providing an automatic reconfigurable retrim …

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Atpg For Reversible Circuits Using Technology-Related Fault Models, Jeff S. Allen, Jacob D. Biamonte, Marek Perkowski Sep 2005

Atpg For Reversible Circuits Using Technology-Related Fault Models, Jeff S. Allen, Jacob D. Biamonte, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

We address the problem of test set generation and test set reduction, to first detect, and later localize faults occurring in reversible circuits. Reversible Computation has high promise of low power consumption. Some new fault models are first presented here. An explanation of the new fault models is made based on a physical realization representing the state of the art in the reversible CMOS circuit technology. Evidence is then presented showing that the fault models presented in the current literature are not adequate for existing realizations of reversible logic such as CMOS. We designed a ATPG software package with a …

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Review Of Digital Control Techniques For Automotive Dc-Dc Converters, Dwaraka S. Padimiti, Mehdi Ferdowsi Sep 2005

Review Of Digital Control Techniques For Automotive Dc-Dc Converters, Dwaraka S. Padimiti, Mehdi Ferdowsi

Electrical and Computer Engineering Faculty Research & Creative Works

Electric and hybrid electric vehicles need a power plant that includes dc-dc converters. While using these converters, their control plays an important role in the overall performance of the vehicle. Due to their several drawbacks including poor communications, analog control schemes are not suitable for the automotive industry, whereas digital control methods successfully meet the demands. Various types of digital control techniques for dc-dc converters are studied and classified in this paper. The drawbacks and advantages of each method are described.

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System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radiation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger Aug 2005

System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radiation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are system and method for a characterizing system consisting of a fluid sample on a two-sided stage, utilizing data obtained by applying, from both sides thereof, beams of electromagnetic radiation to a fluid coated surface in a containing cell volume. The beams can have the same or different wavelength content and/or polarization state and can be applied at the same or different magnitude angles-of-incidence, and a third typically unpolarized beam can be applied at a normal angle-of-incidence.

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System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger Aug 2005

System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are System and method for characterizing a System consisting of a fluid Sample on a two sided Stage, utilizing data obtained by applying, from both sides thereof, beams of electromagnetic radiation to a fluid coated Surface in a containing cell Volume. The beams can have the same or different wavelength content and/or polarization State, and can be applied at the same or different magnitude angles-of-incidence, and a third typically unpolarized beam can be applied at a normal angle-of-incidence.

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Navigation And Control Technologies For Autonomous Micro Vehicles, Randal Beard, Timothy W. Mclain Aug 2005

Navigation And Control Technologies For Autonomous Micro Vehicles, Randal Beard, Timothy W. Mclain

Faculty Publications

Sponsorship: Air Force Research Laboratory / Munitions Directorate. During this project we focused on four primary objectives which are listed below. 1. Magnetometer Integration. Integrate and flight test magnetometers with the current version of the autopilot (Spiral 1). 2. Height-Above-Ground Sensor Integration. Integrate and flight test height-above-ground sensors with the current version of the autopilot (Spiral 1). 3. Automatic Gain Adjustment. Develop and flight test automatic gain adjustment algorithms that automatically tune the servo loops of the autopilot. 4. Automatic Trim Seeking. Develop and flight test automatic trim seeking algorithms to recursively estimate the trim values of the UAV.

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Solid-State Current Amplifier Based On Impact Ionization, Aaron R. Hawkins, Hong-Wei Lee Aug 2005

Solid-State Current Amplifier Based On Impact Ionization, Aaron R. Hawkins, Hong-Wei Lee

Faculty Publications

The operation principle, fabrication, and measurement results for a stand-alone amplifier based on impact ionization are reported. The device was built in silicon using standard microelectronic processes. Testing was performed by connecting the device to both silicon and indium-gallium-arsenide photodiodes to demonstrate its compatibility with arbitrary current sources. Preamplified leakage currents of less than 1 nA were measured along with current gains greater than 100.

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Power Management Integrated Circuits Design, Functionality Analysis And Applications, Zheng Li Aug 2005

Power Management Integrated Circuits Design, Functionality Analysis And Applications, Zheng Li

Electrical Engineering Dissertations - Archive

Power management is playing a significant role in modern electronics. Good power management is especially important for portable devices that rely on batteries. By smartly managing how the power is directed to different components of a system, e.g., reducing power to components that are not being used, the efficiency as well as the battery lifetime can be doubled or tripled. There exists a large family of integrated circuits (IC) that are used for power management, e.g., linear regulators, switching regulators, power controllers, hot swap controllers, etc. The voltage reference is one of the key components in this family. For high …

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Power Integrity Investigation Of Bga Footprints By Means Of The Segmentation Method, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault Aug 2005

Power Integrity Investigation Of Bga Footprints By Means Of The Segmentation Method, Giuseppe Selli, James L. Drewniak, Richard E. Dubroff, Jun Fan, James L. Knighten, Norman W. Smith, Dean Mccoy, Bruce Archambeault

Electrical and Computer Engineering Faculty Research & Creative Works

The engineering of the power delivery network is becoming a fundamental issue in the design of high speed digital systems on PCB's. In fact, providing the required power to the different IC's at the specified noisefree voltage levels allows a correct functioning of the overall PCB systems. More over, the ongoing trend of replacing active devices with peripherally located I/O and PWR/GND pins with areally located I/O and PWR/GND pins (BGA packaged) increases the complexity of the models, when power delivery issues need to be studied in a larger contest, such as the overall PCB's. The employment of the powerful, …

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Neural Network Detection And Identification Of Electronic Devices Based On Their Unintended Emissions, Haixiao Weng, Xiaopeng Dong, Xiao Hu, Daryl G. Beetner, Todd H. Hubing, Donald C. Wunsch Aug 2005

Neural Network Detection And Identification Of Electronic Devices Based On Their Unintended Emissions, Haixiao Weng, Xiaopeng Dong, Xiao Hu, Daryl G. Beetner, Todd H. Hubing, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Electromagnetic emissions were measured from several radio receivers to demonstrate the possibility of detecting and identifying these devices based on their unintended emissions. Radiated fields from the different radio receivers have unique characteristics that can be used to identify these devices by analyzing time-frequency plots of measured radiation. A neural network was also developed for automated device detection.

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