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Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben 2017 Iowa State University

Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben

Leslie Hogben

This paper studies the recursive robust principal components analysis problem. If the outlier is the signal-of-interest, this problem can be interpreted as one of recursively recovering a time sequence of sparse vectors, St, in the presence of large but structured noise, Lt. The structure that we assume on Lt is that Lt is dense and lies in a low-dimensional subspace that is either fixed or changes slowly enough. A key application where this problem occurs is in video surveillance where the goal is to separate a slowly changing background (Lt) from moving foreground objects (St) on-the-fly. To solve the above ...


Zone Based Hybrid Approach For Clustering And Data Collection In Wireless Sensor Networks, Karanam R. Dayananda, Jeremy Straub 2017 North Dakota State University--Fargo

Zone Based Hybrid Approach For Clustering And Data Collection In Wireless Sensor Networks, Karanam R. Dayananda, Jeremy Straub

Jeremy Straub

A wireless sensor network (WSN) is a collection of
spatially distributed autonomous sensor nodes that can be used to
monitor, among other things, environmental conditions. WSN
sensor nodes are constrained by their limited energy supply,
communication range and local computational capabilities. Data
routing is an area that can be optimized to allow nodes to conserve
energy, improving the network’s overall lifetime. Though many
routing protocols can be used, using a clustering protocol can play
an important role in conserving WSN energy. Under this
approach, the network is divided into multiple clusters. The
leader of each cluster supervises data transmission ...


Target Read Operation Of Passive Ultra High Frequency Rfid Tag In A Multiple Tags Environment, Zi Qin Phua 2017 University of Kentucky

Target Read Operation Of Passive Ultra High Frequency Rfid Tag In A Multiple Tags Environment, Zi Qin Phua

Theses and Dissertations--Mechanical Engineering

Passive ultra-high frequency (UHF) radio frequency Identification (RFID) has emerged as a promising solution for many industrial applications. Passive UHF systems are relatively inexpensive to implement and monitor, as no line of sight is required for the communication. There are several advantages to using a passive RFID system. For example, no internal power source is required to activate the tags, and lower labor costs and efficient multitasking operations are expected in a long term scenario. However, due to factors such as tag-to-tag interference and inaccurate localization, RFID tags that are closely spaced together are difficult to detect and program accurately ...


A Quantitative Measure Of Mono-Componentness For Time-Frequency Analysis, Austin P. Albright 2016 University of Tennessee, Knoxville

A Quantitative Measure Of Mono-Componentness For Time-Frequency Analysis, Austin P. Albright

Doctoral Dissertations

Joint time-frequency (TF) analysis is an ideal method for analyzing non-stationary signals, but is challenging to use leading to it often being neglected. The exceptions being the short-time Fourier transform (STFT) and spectrogram. Even then, the inability to have simultaneously high time and frequency resolution is a frustrating issue with the STFT and spectrogram. However, there is a family of joint TF analysis techniques that do have simultaneously high time and frequency resolution – the quadratic TF distribution (QTFD) family. Unfortunately, QTFDs are often more troublesome than beneficial. The issue is interference/cross-terms that causes these methods to become so difficult ...


Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang 2016 University of Louisville

Single Carrier Frequency Domain Equalization And Energy Efficiency Optimization For Mimo Cognitive Radio., Xiaohui Zhang

Electronic Theses and Dissertations

This dissertation studies two separate topics in wireless communication systems. One topic focuses on the Single Carrier Frequency Domain Equalization (SC-FDE), which is a promising technique to mitigate the multipath effect in the broadband wireless communication. Another topic targets on the energy efficiency optimization in a multiple input multiple output (MIMO) cognitive radio network. For SC-FDE, the conventional linear receivers suffer from the noise amplification in deep fading channel. To overcome this, a fractional spaced frequency domain (FSFD) receiver based on frequency domain oversampling (FDO) is proposed for SC-FDE to improve the performance of the linear receiver under deep fading ...


Improved Localization Algorithms In Indoor Wireless Environment, Fei Long 2016 The University of Western Ontario

Improved Localization Algorithms In Indoor Wireless Environment, Fei Long

Electronic Thesis and Dissertation Repository

Localization has been considered as an important precondition for the location-dependent applications such as mobile tracking and navigation.To obtain specific location information, we usually make use of Global Positioning System(GPS), which is the most common plat- form to acquire localization information in outdoor environments. When targets are in indoor environment, however, the GPS signal is usually blocked, so we also consider other assisted positioning techniques in order to obtain accurate position of targets. In this thesis, three different schemes in indoor environment are proposed to minimize localization error by placing refer- ence nodes in optimum locations, combining the ...


Channel And Noise Variance Estimation For Future 5g Cellular Networks, Jorge Iscar Vergara 2016 Florida International University

Channel And Noise Variance Estimation For Future 5g Cellular Networks, Jorge Iscar Vergara

FIU Electronic Theses and Dissertations

Future fifth generation (5G) cellular networks have to cope with the expected ten-fold increase in mobile data traffic between 2015 and 2021. To achieve this goal, new technologies are being considered, including massive multiple-input multiple-output (MIMO) systems and millimeter-wave (mmWave) communications. Massive MIMO involves the use of large antenna array sizes at the base station, while mmWave communications employ frequencies between 30 and 300 GHz. In this thesis we study the impact of these technologies on the performance of channel estimators.

Our results show that the characteristics of the propagation channel at mmWave frequencies improve the channel estimation performance in ...


Segmentation Of Pulmonary Nodules In Computed Tomography Using A Regression Neural Network Approach And Its Application To The Lung Image Database Consortium And Image Database Resource Initiative Dataset, Temesguen Messay, Russell C. Hardie, Timothy R. Tuinstra 2016 University of Dayton

Segmentation Of Pulmonary Nodules In Computed Tomography Using A Regression Neural Network Approach And Its Application To The Lung Image Database Consortium And Image Database Resource Initiative Dataset, Temesguen Messay, Russell C. Hardie, Timothy R. Tuinstra

Timothy R Tuinstra, Ph.D.

We present new pulmonary nodule segmentation algorithms for computed tomography (CT). These include a fully-automated (FA) system, a semi-automated (SA) system, and a hybrid system. Like most traditional systems, the new FA system requires only a single user-supplied cue point. On the other hand, the SA system represents a new algorithm class requiring 8 user-supplied control points. This does increase the burden on the user, but we show that the resulting system is highly robust and can handle a variety of challenging cases. The proposed hybrid system starts with the FA system. If improved segmentation results are needed, the SA ...


Examination Of The Nonlinear Dynamics And Possible Chaos Encryption In A Zeroth-Order Acousto-Optic Bragg Modulator With Feedback, Fares S. Almehmadi, Monish Ranjan Chatterjee 2016 University of Tabuk

Examination Of The Nonlinear Dynamics And Possible Chaos Encryption In A Zeroth-Order Acousto-Optic Bragg Modulator With Feedback, Fares S. Almehmadi, Monish Ranjan Chatterjee

Monish R. Chatterjee

Zeroth-order chaos modulation in a Bragg cell is examined such that tracking problems due to spatial deflections of the first-order AO beam at the receiver may be avoided by switching to the undeviated zeroth-order beam.


Efficient Macromodeling Techniques Of Distributed Networks Using Tabulated Data, Mohamed Sahouli 2016 The University of Western Ontario

Efficient Macromodeling Techniques Of Distributed Networks Using Tabulated Data, Mohamed Sahouli

Electronic Thesis and Dissertation Repository

Efficient macromodeling techniques used to model multi-port distributed systems using tabulated data are presented. First a method to macromodel large multiport systems characterized by noisy frequency domain data is shown. The proposed method is based on the vector fitting algorithm and uses an instrumental variable approach and QR decomposition to formulate the least squares equations. The instrumental variable method minimizes the biasing effect of the least squares solution caused by the noise of the data samples while QR decomposition decouples the least squares equations of multiport systems described by common set of poles. It is illustrated, that the proposed approach ...


Controlling And Processing Core For Wireless Implantable Telemetry System, Naeeme Modir 2016 The University of Western Ontario

Controlling And Processing Core For Wireless Implantable Telemetry System, Naeeme Modir

Electronic Thesis and Dissertation Repository

Wireless implantable telemetry systems are suitable choices for monitoring various physiological parameters such as blood pressure and volume. These systems typically compose of an internal device implanted into a living body captures the physiological data and sends them to an external base station located outside of the body for further processing. The internal device usually consists of a sensor interface to convert the collected data to electrical signals; a digital core to digitize the analog signals, process them and prepare them for transmission; an RF front-end to transmit the data outside the body and to receive the required commands from ...


Examination Of The Nonlinear Dynamics And Possible Chaos Encryption In A Zeroth-Order Acousto-Optic Bragg Modulator With Feedback, Fares S. Almehmadi, Monish Ranjan Chatterjee 2016 University of Tabuk

Examination Of The Nonlinear Dynamics And Possible Chaos Encryption In A Zeroth-Order Acousto-Optic Bragg Modulator With Feedback, Fares S. Almehmadi, Monish Ranjan Chatterjee

Electrical and Computer Engineering Faculty Publications

Zeroth-order chaos modulation in a Bragg cell is examined such that tracking problems due to spatial deflections of the first-order AO beam at the receiver may be avoided by switching to the undeviated zeroth-order beam.


Nonlinear Dynamics, Bifurcation Maps, Signal Encryption And Decryption Using Acousto-Optic Chaos Under A Variable Aperture Illumination, Monish Ranjan Chatterjee, Suman Chaparala 2016 University of Dayton

Nonlinear Dynamics, Bifurcation Maps, Signal Encryption And Decryption Using Acousto-Optic Chaos Under A Variable Aperture Illumination, Monish Ranjan Chatterjee, Suman Chaparala

Electrical and Computer Engineering Faculty Publications

Bragg cell nonlinear dynamics and bifurcation properties under first-order feedback with variable aperture are examined. Chaotic encryption and recovery of low-bandwidth signals, and optimal performance are evaluated for fixed and variable apertures.


Dynamical Model Of Harmonic Generation In Centrosymmetric Semiconductors At Visible And Uv Wavelengths, Michael Scalora, Maria Antonietta Vincenti, Domenico de Ceglia, N. Akozbek, Vito Roppo, M. J. Bloemer, Joseph W. Haus 2016 Charles M. Bowden Research Center

Dynamical Model Of Harmonic Generation In Centrosymmetric Semiconductors At Visible And Uv Wavelengths, Michael Scalora, Maria Antonietta Vincenti, Domenico De Ceglia, N. Akozbek, Vito Roppo, M. J. Bloemer, Joseph W. Haus

Joseph W Haus

We study second and third harmonic generation in centrosymmetric semiconductors at visible and UV wavelengths in bulk and cavity environments. Second harmonic generation is due to a combination of spatial symmetry breaking, the magnetic portion of the Lorentz force, and quadrupolar contributions from inner core electrons. The material is assumed to have a nonzero, third-order nonlinearity that gives rise to most of the third harmonic signal. Using the parameters of bulk silicon we predict that cavity environments modify the dependence of second harmonic generation on incident angle, while improving third harmonic conversion efficiency by several orders of magnitude relative to ...


Tailoring Metallodielectric Structures For Superresolution And Superguiding Applications In The Visible And Near-Ir Ranges, Domenico de Ceglia, Maria Antonietta Vincenti, M. G. Cappeddu, Marco Centini, Neset Akozbek, Antonella D'Orazio, Joseph W. Haus, Mark J. Bloemer, Michael Scalora 2016 Charles M. Bowden Research Center

Tailoring Metallodielectric Structures For Superresolution And Superguiding Applications In The Visible And Near-Ir Ranges, Domenico De Ceglia, Maria Antonietta Vincenti, M. G. Cappeddu, Marco Centini, Neset Akozbek, Antonella D'Orazio, Joseph W. Haus, Mark J. Bloemer, Michael Scalora

Joseph W Haus

We discuss propagation effects in realistic, transparent, metallodielectric photonic band gap structures in the context of negative refraction and super-resolution in the visible and near infrared ranges. In the resonance tunneling regime, we find that for transverse-magnetic incident polarization, field localization effects contribute to a waveguiding phenomenon that makes it possible for the light to remain confined within a small fraction of a wavelength, without any transverse boundaries, due to the suppression of diffraction. This effect is related to negative refraction of the Poynting vector inside each metal layer, balanced by normal refraction inside the adjacent dielectric layer: The degree ...


Second-Harmonic Double-Resonance Cones In Dispersive Hyperbolic Metamaterials, Domenico de Ceglia, Maria Antonietta Vincenti, Salvatore Campione, Filippo Capolino, Joseph W. Haus, Michael Scalora 2016 Charles M. Bowden Research Center

Second-Harmonic Double-Resonance Cones In Dispersive Hyperbolic Metamaterials, Domenico De Ceglia, Maria Antonietta Vincenti, Salvatore Campione, Filippo Capolino, Joseph W. Haus, Michael Scalora

Joseph W Haus

We study the formation of second-harmonic double-resonance cones in hyperbolic metamaterials. An electric dipole on the surface of the structure induces second-harmonic light to propagate into two distinct volume plasmon-polariton channels: a signal that propagates within its own peculiar resonance cone and a phase-locked signal that is trapped under the pump's resonance cone. Metamaterial dispersion and birefringence induce a large angular divergence between the two volume plasmon polaritons, making these structures suitable for subwavelength second- and higher-harmonic imaging microscopy.


Nonlocal And Quantum-Tunneling Contributions To Harmonic Generation In Nanostructures: Electron-Cloud-Screening Effects, Michael Scalora, Maria Antonietta Vincenti, Domenico de Ceglia, Joseph W. Haus 2016 Charles M. Bowden Research Center

Nonlocal And Quantum-Tunneling Contributions To Harmonic Generation In Nanostructures: Electron-Cloud-Screening Effects, Michael Scalora, Maria Antonietta Vincenti, Domenico De Ceglia, Joseph W. Haus

Joseph W Haus

Our theoretical examination of second- and third-harmonic generation from metal-based nanostructures predicts that nonlocal and quantum-tunneling phenomena can significantly exceed expectations based solely on local, classical electromagnetism. Mindful that the diameter of typical transition-metal atoms is approximately 3 Å, we adopt a theoretical model that treats nanometer-size features and/or subnanometer-size gaps or spacers by taking into account (i) the limits imposed by atomic size to fulfill the requirements of continuum electrodynamics, (ii) spillage of the nearly free electron cloud into the surrounding vacuum, and (iii) the increased probability of quantum tunneling as objects are placed in close proximity.

Our ...


Dynamical Model Of Harmonic Generation In Centrosymmetric Semiconductors At Visible And Uv Wavelengths, Michael Scalora, Maria Antonietta Vincenti, Domenico de Ceglia, N. Akozbek, Vito Roppo, M. J. Bloemer, Joseph W. Haus 2016 Charles M. Bowden Research Center

Dynamical Model Of Harmonic Generation In Centrosymmetric Semiconductors At Visible And Uv Wavelengths, Michael Scalora, Maria Antonietta Vincenti, Domenico De Ceglia, N. Akozbek, Vito Roppo, M. J. Bloemer, Joseph W. Haus

Joseph W Haus

We study second and third harmonic generation in centrosymmetric semiconductors at visible and UV wavelengths in bulk and cavity environments. Second harmonic generation is due to a combination of spatial symmetry breaking, the magnetic portion of the Lorentz force, and quadrupolar contributions from inner core electrons. The material is assumed to have a nonzero, third-order nonlinearity that gives rise to most of the third harmonic signal. Using the parameters of bulk silicon we predict that cavity environments modify the dependence of second harmonic generation on incident angle, while improving third harmonic conversion efficiency by several orders of magnitude relative to ...


Inhibition Of Linear Absorption In Opaque Materials Using Phase-Locked Harmonic Generation, Marco Centini, Vito Roppo, Eugenio Fazio, Federico Pettazzi, Concita Sibilia, Joseph W. Haus, John V. Foreman, Neset Akozbek, Mark J. Bloemer, Michael Scalora 2016 University of Rome La Sapienza

Inhibition Of Linear Absorption In Opaque Materials Using Phase-Locked Harmonic Generation, Marco Centini, Vito Roppo, Eugenio Fazio, Federico Pettazzi, Concita Sibilia, Joseph W. Haus, John V. Foreman, Neset Akozbek, Mark J. Bloemer, Michael Scalora

Joseph W Haus

We theoretically predict and experimentally demonstrate inhibition of linear absorption for phase and group velocity mismatched second- and third-harmonic generation in strongly absorbing materials, GaAs, in particular, at frequencies above the absorption edge.

A 100-fs pump pulse tuned to 1300 nm generates 650 and 435 nm second- and third-harmonic pulses that propagate across a 450−μm-thick GaAs substrate without being absorbed.

We attribute this to a phase-locking mechanism that causes the pump to trap the harmonics and to impress on them its dispersive properties.


Harmonic Generation In Multiresonant Plasma Films, Maria Antonietta Vincenti, Domenico de Ceglia, Joseph W. Haus, Michael Scalora 2016 Charles M. Bowden Research Center

Harmonic Generation In Multiresonant Plasma Films, Maria Antonietta Vincenti, Domenico De Ceglia, Joseph W. Haus, Michael Scalora

Joseph W Haus

We investigate second- and third-harmonic generation in a slab of material that displays plasma resonances at the pump and its harmonic frequencies. Near-zero refractive indices and local field enhancement can deplete the pump for kW/cm2 incident powers, without resorting to other resonant photonic mechanisms. We show that low-threshold, highly efficient nonlinear processes are possible in the presence of losses and phase mismatch in structures that are 104 times shorter than typical nonlinear crystals, for relatively low irradiance values.


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