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Full-Text Articles in Systems and Communications

Flor Revisited (Again): Eqtl And Mutational Analysis Of Nb-Lrr Mediated Immunity To Powdery Mildew In Barley, Roger P. Wise, Priyanka Surana, Gregory S. Fuerst, Ruo Xu, Divya Mistry, Julie A. Dickerson, Dan Nettleton Dr. Jun 2019

Flor Revisited (Again): Eqtl And Mutational Analysis Of Nb-Lrr Mediated Immunity To Powdery Mildew In Barley, Roger P. Wise, Priyanka Surana, Gregory S. Fuerst, Ruo Xu, Divya Mistry, Julie A. Dickerson, Dan Nettleton Dr.

Dan Nettleton

Genes encoding early signaling events in pathogen defense often are identified only by their phenotype. Such genes involved in barley-powdery mildew interactions include Mla, specifying race-specific resistance; Rar1 (Required for Mla12-specified resistance1), and Rom1 (Restoration of Mla-specified resistance1). The HSP90-SGT1-RAR1 complex appears to function as chaperone in MLA-specified resistance, however, much remains to be discovered regarding the precise signaling underlying plant immunity. Genetic analyses of fast-neutron mutants derived from CI 16151 (Mla6) uncovered a novel locus, designated Rar3 (Required for Mla6-specified resistance3). Rar3 segregates independent of Mla6 and Rar1, and rar3 mutants are susceptible to Blumeria graminis f. sp. hordei …


Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay Jun 2017

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Russell C. Hardie

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii) …


Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. Lemaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch Jun 2017

Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. Lemaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch

Russell C. Hardie

Differential tilt variance is a useful metric for interpreting the distorting effects of turbulence in incoherent imaging systems. In this paper, we compare the theoretical model of differential tilt variance to simulations. Simulation is based on a Monte Carlo wave optics approach with split step propagation. Results show that the simulation closely matches theory. The results also show that care must be taken when selecting a method to estimate tilts.


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

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

Namrata Vaswani

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 …


Network Connection Blocker, Method, And Computer Readable Memory For Monitoring Connections In A Computer Network And Blocking The Unwanted Connections, Douglas W. Jacobson, James A. Davis Jun 2017

Network Connection Blocker, Method, And Computer Readable Memory For Monitoring Connections In A Computer Network And Blocking The Unwanted Connections, Douglas W. Jacobson, James A. Davis

Douglas Jacobson

A network connection blocker for monitoring connections between host computers in a network and blocking the unwanted connections. The host computers transmit connection packets between each other in accordance with a network protocol suite when seeking to establish, providing network services with, and close the connections. The network protocol suite includes a connection oriented transport layer protocol. The network connection blocker comprises a network interface that receives the connection packets transmitted between the host computers. It also comprises a blocking module that processes the received connection packets to detect the unwanted connections. The blocking module then generates connection packets in …


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 Oct 2016

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.


Gaussian Weighted Neighborhood Connectivity Of Nonlinear Line Attractor For Learning Complex Manifolds, Theus H. Aspiras, Vijayan K. Asari, Wesam Sakla Oct 2016

Gaussian Weighted Neighborhood Connectivity Of Nonlinear Line Attractor For Learning Complex Manifolds, Theus H. Aspiras, Vijayan K. Asari, Wesam Sakla

Vijayan K. Asari

The human brain has the capability to process high quantities of data quickly for detection and recognition tasks. These tasks are made simpler by the understanding of data, which intentionally removes redundancies found in higher dimensional data and maps the data onto a lower dimensional space. The brain then encodes manifolds created in these spaces, which reveal a specific state of the system. We propose to use a recurrent neural network, the nonlinear line attractor (NLA) network, for the encoding of these manifolds as specific states, which will draw untrained data towards one of the specific states that the NLA …


Histogram Of Oriented Phase And Gradient (Hopg) Descriptor For Improved Pedestrian Detection, Hussin Ragb, Vijayan K. Asari Oct 2016

Histogram Of Oriented Phase And Gradient (Hopg) Descriptor For Improved Pedestrian Detection, Hussin Ragb, Vijayan K. Asari

Vijayan K. Asari

This paper presents a new pedestrian detection descriptor named Histogram of Oriented Phase and Gradient (HOPG) based on a combination of the Histogram of Oriented Phase (HOP) features and the Histogram of Oriented Gradient features (HOG). The proposed descriptor extracts the image information using both the gradient and phase congruency concepts. Although the HOG based method has been widely used in the human detection systems, it lacks to deal effectively with the images impacted by the illumination variations and cluttered background. By fusing HOP and HOG features, more structural information can be identified and localized in order to obtain more …


Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari Oct 2016

Histogram Of Oriented Phase (Hop): A New Descriptor Based On Phase Congruency, Hussin Ragb, Vijayan K. Asari

Vijayan K. Asari

In this paper we present a low level image descriptor called Histogram of Oriented Phase based on phase congruency concept and the Principal Component Analysis (PCA). Since the phase of the signal conveys more information regarding signal structure than the magnitude, the proposed descriptor can precisely identify and localize image features over the gradient based techniques, especially in the regions affected by illumination changes. The proposed features can be formed by extracting the phase congruency information for each pixel in the image with respect to its neighborhood. Histograms of the phase congruency values of the local regions in the image …


A Modular Approach For Key-Frame Selection In Wide Area Surveillance Video Analysis, Almabrok Essa, Paheding Sidike, Vijayan K. Asari Oct 2016

A Modular Approach For Key-Frame Selection In Wide Area Surveillance Video Analysis, Almabrok Essa, Paheding Sidike, Vijayan K. Asari

Vijayan K. Asari

This paper presents an efficient preprocessing algorithm for big data analysis. Our proposed key-frame selection method utilizes the statistical differences among subsequent frames to automatically select only the frames that contain the desired contextual information and discard the rest of the insignificant frames.

We anticipate that such key frame selection technique will have significant impact on wide area surveillance applications such as automatic object detection and recognition in aerial imagery. Three real-world datasets are used for evaluation and testing and the observed results are encouraging.


A Robust Fringe-Adjusted Joint Transform Correlator For Efficient Object Detection, Paheding Sidike, Vijayan K. Asari, Mohammad S. Alam Oct 2016

A Robust Fringe-Adjusted Joint Transform Correlator For Efficient Object Detection, Paheding Sidike, Vijayan K. Asari, Mohammad S. Alam

Vijayan K. Asari

The fringe-adjusted joint transform correlation (FJTC) technique has been widely used for real-time optical pattern recognition applications. However, the classical FJTC technique suffers from target distortions due to noise, scale, rotation and illumination variations of the targets in input scenes. Several improvements of the FJTC have been proposed in the literature to accommodate these problems. Some popular techniques such as synthetic discriminant function (SDF) based FJTC was designed to alleviate the problems of scale and rotation variations of the target, whereas wavelet based FJTC has been found to yield better performance for noisy targets in the input scenes. While these …


Creation Of Carbon Nanotube Based Biosensors Through Dielectrophoretic Assembly, Nilan S. Mani, Steve Kim, Kaushik Annam, Danielle Bane, Guru Subramanyam Sep 2016

Creation Of Carbon Nanotube Based Biosensors Through Dielectrophoretic Assembly, Nilan S. Mani, Steve Kim, Kaushik Annam, Danielle Bane, Guru Subramanyam

Guru Subramanyam

Due to their excellent electrical, optical, and mechanical properties, nanosized single wall carbon nanotubes (SWNTs) have attracted significant attention as a transducing element in nano-bio sensor research. Controlled assembly, device fabrication, and bio-functionalization of the SWNTs are crucial in creating the sensors. In this study, working biosensor platforms were created using dielectrophoretic assembly of single wall carbon nanotubes (SWNTs) as a bridge between two gold electrodes. SWNTs in a commercial SDS surfactant solution were dispensed in the gap between the two gold electrodes, followed by applying an ac voltage across the two electrodes. The dielectrophoresis aligns the CNTs and forms …


Dna Based Electrolyte/Separator For Lithium Battery Application, Jitendra Kumar, Fahima Ouchen-Bouchendouka, Devin A. Smarra, Guru Subramanyam, James Grote Sep 2016

Dna Based Electrolyte/Separator For Lithium Battery Application, Jitendra Kumar, Fahima Ouchen-Bouchendouka, Devin A. Smarra, Guru Subramanyam, James Grote

Guru Subramanyam

In this study, we demonstrated the use of DNA-CTMA (DC) in combination with PolyVinylidene Fluoride (PVDF) as a host matrix or separator for Lithium based electrolyte to form solid polymer/gel like electrolyte for potential application in Li-ion batteries.

The addition of DC provided a better thermal stability of the composite electrolyte as shown by the thermos-gravimetric analysis (TGA). The AC conductivity measurements suggest that the addition of DC to the gel electrolyte had no effect on the overall ionic conductivity of the composite. The obtained films are flexible with high mechanical stretch-ability as compared to the gel type electrolytes only.


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 Sep 2016

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

Russell C. Hardie

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 …


Translation Of 'Profiles In Faith', Monish Ranjan Chatterjee Aug 2016

Translation Of 'Profiles In Faith', Monish Ranjan Chatterjee

Monish R. Chatterjee

Sarat Chandra Chatterjee (1876-1938) may be considered one of the three most significant figures of the literary component of the Bengal Renaissance, the other two being Bankim Chandra Chatterjee (1838-1894) and Rabindranath Tagore (1861-1941). As much as Bankim Chandra is identified with the new age in the Bengali novel, and the development of serious vernacular journalism, and Rabindranath with modern/classical movements in Bengali poetry and music, along with novel ideas in methods of education and teaching, Sarat Chandra, as a novelist and storyteller, perfected the art of narration and critical analyses of a variety of contemporaneous social and political issues, …


Translation Of 'Seasons Of Life: A Panoramic Selection Of Songs By Rabindranath Tagore', Monish Ranjan Chatterjee Aug 2016

Translation Of 'Seasons Of Life: A Panoramic Selection Of Songs By Rabindranath Tagore', Monish Ranjan Chatterjee

Monish R. Chatterjee

No abstract provided.


Translation Of 'Balika Badhu: A Selected Anthology Of Bengali Short Stories', Monish Ranjan Chatterjee Aug 2016

Translation Of 'Balika Badhu: A Selected Anthology Of Bengali Short Stories', Monish Ranjan Chatterjee

Monish R. Chatterjee

This project, which began with the desire to render into English a rather long tale by Bimal Kar about five years ago, eventually grew into a considerably more extended compilation of Bengali short stories by 10 of the most well-known practitioners of that art since the heyday of Rabindranath Tagore. The collection is limited in many ways, not the least of which being that no woman writer has been included, and that it contains only a baker's dozen stories (if we count Bonophool's micro-stories collectively as one ) — a number pitifully small considering the vast and prolific field of …


Translation Of 'Kamalakanta: A Collection Of Satirical Essays And Reflections', Monish Ranjan Chatterjee Aug 2016

Translation Of 'Kamalakanta: A Collection Of Satirical Essays And Reflections', Monish Ranjan Chatterjee

Monish R. Chatterjee

This venture was born initially out of the desire to make those works of Bengali literature which have moved me profoundly, and which I consider first-rate by any yardstick, available to friends and fellow enthusiasts who cannot read the original. In attempting to channel literary and philosophical masterpieces into a different medium, I Have experienced firsthand the formidable challenge that a translator must face because not only of the barrier imposed by the languages involved, but perhaps more so because .of his or her own severely inadequate faculty being called upon to match both the genius and the inspiration of …


Spectral And Performance Analysis For The Propagation And Retrieval Of Signals From Modulated Chaos Waves Transmitted Through Modified Von Karman Turbulence, Fathi H.A. Mohamed, Monish Ranjan Chatterjee Aug 2016

Spectral And Performance Analysis For The Propagation And Retrieval Of Signals From Modulated Chaos Waves Transmitted Through Modified Von Karman Turbulence, Fathi H.A. Mohamed, Monish Ranjan Chatterjee

Monish R. Chatterjee

A transfer function formalism is applied to track propagation of modulated chaos waves through modified von Karman phase turbulence; the demodulated signal is examined vis-à-vis performance relative to turbulence strength in comparison with non-chaotic propagation.


Examination Of Chaotic Signal Encryption And Recovery For Secure Communication Using Hybrid Acousto-Optic Feedback, Monish Ranjan Chatterjee, Mohammed A. Al-Saedi Aug 2016

Examination Of Chaotic Signal Encryption And Recovery For Secure Communication Using Hybrid Acousto-Optic Feedback, Monish Ranjan Chatterjee, Mohammed A. Al-Saedi

Monish R. Chatterjee

Generation of chaos from acousto-optic (A-O)Bragg cell modulators with an electronic feedback has been studied for over 3 decades. Since an acousto-optic Bragg cell with zeroth- and first-order feedback exhibits chaotic behavior past the threshold for bistability, such a system was recently examined for possible chaotic encryption of simple messages (such as a low-amplitude sinusoidal signal) applied via the bias input of the sound cell driver. Subsequent recovery of the message signal was carried out via a heterodyne-type strategy employing a locally generated chaotic carrier, with threshold parameters matched to the transmitting Bragg cell. In this paper, we present numerical …


Spectral Analysis Of Encrypted Chaotic Signals Using Fast Fourier Transforms And Laboratory Spectral Analyzers, Monish Ranjan Chatterjee, Abhinay Kundur Aug 2016

Spectral Analysis Of Encrypted Chaotic Signals Using Fast Fourier Transforms And Laboratory Spectral Analyzers, Monish Ranjan Chatterjee, Abhinay Kundur

Monish R. Chatterjee

The use of acousto-optic chaos, as manifested via first-order feedback in an acousto-optic Bragg cell, in encrypting a message wave and subsequently recovering the message in the receiver using a chaotic heterodyne strategy, has been reported recently [1-3]. In examining the dynamical system analytically using computer simulation, (expected) modulated chaos waveforms are obtained within specified observation windows. Because of the relatively random nature inherent in chaos waveforms, it is essentially impossible to ascertain from the visual display of the chaotic wave whether a given message signal has in fact modulated the chaotic "carrier". In fact, it has been observed from …


Revisiting The Fresnel Coefficients For Uniform Plane Wave Propagation Across A Nonchiral, Reciprocal And Chiral, Nonreciprocal Interface, Monish Ranjan Chatterjee, Sumit Nema Aug 2016

Revisiting The Fresnel Coefficients For Uniform Plane Wave Propagation Across A Nonchiral, Reciprocal And Chiral, Nonreciprocal Interface, Monish Ranjan Chatterjee, Sumit Nema

Monish R. Chatterjee

The problem of EM wave propagation in non-reciprocal chiral media has been studied by several investigators. In a recent approach, a dual-transform technique has been developed to study the problem of such propagation under paraxial and slow-envelope variation conditions. In this paper, we first outline some of the results obtained using the dual transform technique for arbitrary boundary conditions within the left boundary of a semi-infinite, non-reciprocal chiral medium for a uniform plane wave, and a fundamental Gaussian-profiled beam. Next, we explore the problem of a uniform EM wave incident at an oblique angle at an interface between a reciprocal, …


Realization Of Negative Index In Second-Order Dispersive Metamaterials Using Standard Dispersion Models For Electromagnetic Parameters, Tarig A. Algadey, Monish Ranjan Chatterjee Aug 2016

Realization Of Negative Index In Second-Order Dispersive Metamaterials Using Standard Dispersion Models For Electromagnetic Parameters, Tarig A. Algadey, Monish Ranjan Chatterjee

Monish R. Chatterjee

In recent work, electromagnetic propagation velocities for plane waves in dispersive metamaterials were calculated assuming frequency dispersion up to the second order. The three velocities were expressed in terms of dispersive coefficients under certain simplifying constraints. Frequency domains were found to exist around resonances where group and phase velocities are in opposition, implying possible negative index behavior. In this paper, we incorporate in the derived equations physical models (including Debye, Lorentz and Condon) for material dispersion in permittivity, permeability and chirality in order to further examine the consequences of second-order dispersion leading to negative index for practical cases, and also …


Split-Step Approach To Electromagnetic Propagation Through Atmospheric Turbulence Using The Modified Von Karman Spectrum And Planar Apertures, Monish Ranjan Chatterjee, Fathi H.A. Mohamed Aug 2016

Split-Step Approach To Electromagnetic Propagation Through Atmospheric Turbulence Using The Modified Von Karman Spectrum And Planar Apertures, Monish Ranjan Chatterjee, Fathi H.A. Mohamed

Monish R. Chatterjee

The impact of atmospheric phase turbulence on Gaussian beam propagation along propagation paths of varying lengths is examined using multiple random phase screens. The work is motivated by research involving generation and encryption of acousto-optic chaos, and the interest in examining propagation of such chaotic waves through atmospheric turbulence. A phase screen technique is used to simulate perturbations to the refractive index of the medium through the propagation path. A power spectral density based on the modified von Karman spectrum model for turbulence is used to describe the random phase behavior of the medium. In recent work, results for the …


Overview Of Acousto-Optic Bistability, Chaos, And Logical Applications, Monish Ranjan Chatterjee, Erol Sonmez Aug 2016

Overview Of Acousto-Optic Bistability, Chaos, And Logical Applications, Monish Ranjan Chatterjee, Erol Sonmez

Monish R. Chatterjee

An overview is presented of the key results in the field of acousto-optic bistability in the past two decades. It is shown that the basic acousto-optic bistable device may be described as a nonlinear dynamical system which satisfies a quadratic map. Thereafter, details are presented of several analytical methods, computer modeling approaches, including the SPICE circuit modeling technique, and experiments that have been used to understand the phenomenon. Extensions to logical and digital applications are also discussed.


Secure Transmission Of Static And Dynamic Images Via Chaotic Encryption In Acousto-Optic Hybrid Feedback With Profiled Light Beams, Monish Ranjan Chatterjee, Fares S. Almehmadi Aug 2016

Secure Transmission Of Static And Dynamic Images Via Chaotic Encryption In Acousto-Optic Hybrid Feedback With Profiled Light Beams, Monish Ranjan Chatterjee, Fares S. Almehmadi

Monish R. Chatterjee

Secure information encryption via acousto-optic (AO) chaos with profiled optical beams indicates substantially better performance in terms of system robustness. This paper examines encryption of static and time-varying (video) images onto AO chaotic carriers using Gaussian-profile beams with diffracted data numerically generated using transfer functions. The use of profiled beams leads to considerable improvement in the encrypted signal. While static image encryption exhibits parameter tolerances within about ±10% for uniform optical beams, profiled beams reduce the tolerance to less than 1%, thereby vastly improving both the overall security of the transmitted information as well as the quality of the image …


Secure Transmission And Retrieval Of Images In Conjunction With Steganography Using Chaos In Nonlinear Acousto-Optic Feedback, Monish Ranjan Chatterjee, Fares S. Almehmadi Aug 2016

Secure Transmission And Retrieval Of Images In Conjunction With Steganography Using Chaos In Nonlinear Acousto-Optic Feedback, Monish Ranjan Chatterjee, Fares S. Almehmadi

Monish R. Chatterjee

Digital images are encrypted onto a chaotic carrier in a Bragg cell under hybrid nonlinear feedback and secure data is embedded into the system via steganography. System robustness (with and without channel noise) is analyzed vis-a-vis information security.


Numerical Examination Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With Positive Feedback Under Profiled Beam Propagation, Fares S. Almehmadi, Monish Ranjan Chatterjee Aug 2016

Numerical Examination Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With Positive Feedback Under Profiled Beam Propagation, Fares S. Almehmadi, Monish Ranjan Chatterjee

Monish R. Chatterjee

In standard weak interaction theory, acousto-optic Bragg analysis typically assumes that the incident light and sound beams are uniform plane waves. Acousto-optic Bragg diffraction with nonuniform profiled input beams is numerically examined under open loop via a transfer function formalism. Unexpected deviations in the first-order diffracted beam from the standard theory are observed for high 𝑄 values. These deviations are significant because the corresponding closed-loop system is sensitive to input amplitudes and initial conditions, and the overall impact on the dynamical behavior has not been studied previously in standard analyses. To explore the effect of such nonuniform output profiles on …


Numerical Examination Of Acousto-Optic Bragg Interactions For Profiled Lightwaves Using A Transfer Function Formalism, Monish Ranjan Chatterjee, Fares S. Almehmadi Aug 2016

Numerical Examination Of Acousto-Optic Bragg Interactions For Profiled Lightwaves Using A Transfer Function Formalism, Monish Ranjan Chatterjee, Fares S. Almehmadi

Monish R. Chatterjee

Classically, acousto-optic (AO) interactions comprise scattering of photons by energetic phonons into higher and lower orders. Standard weak interaction theory describes diffraction in the Bragg regime as the propagation of a uniform plane wave of light through a uniform plane wave of sound, resulting in the well-known first- and zeroth-order diffraction. Our preliminary investigation of the nature of wave diffraction and photon scattering from a Bragg cell under intensity feedback with profiled light beams indicates that the diffracted (upshifted photon) light continues to maintain the expected (uniform plane wave) behavior versus the optical phase shift in the cell within a …


Numerical Investigation Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With A Variable Feedback Gain, Monish Ranjan Chatterjee, Hao Zhou Aug 2016

Numerical Investigation Of The Nonlinear Dynamics Of A Hybrid Acousto-Optic Bragg Cell With A Variable Feedback Gain, Monish Ranjan Chatterjee, Hao Zhou

Monish R. Chatterjee

Since around 1979, the operation of an acousto-optic Bragg cell under positive first-order feedback via amplification and delay in the loop has been studied extensively by several groups [1-3]. In recent work, the analysis of the nonlinear dynamics (NLD) of the system was extended to include bistable maps and Lyapunov exponents, and application of the chaos for signal encryption and decryption for uniform plane waves. The present work originated with the problem of a variable photodetector aperture opening relative to the first-order light. This potentially complex problem is simplified by assuming instead a variable feedback gain ( β ~ (t)), …