Electrical and Computer Engineering Commons^™

Volume Holographic Recording And Readout For 90-Deg Geometry, Partha P. Banerjee, Monish Ranjan Chatterjee, Nickolai Kukhtarev, Tatiana Kukhtareva

Electrical and Computer Engineering Faculty Publications

When a prerecorded cross-beam hologram is reconstructed (so-called edge-lit readout) with a uniform plane wave and a point source, the resulting exact solutions reveal Bessel-function-type diffracted beam profiles, which are fundamentally modified under weak propagational diffraction. The case of a profiled beam readout with propagational diffraction may be analyzed using a transfer function approach based on 2-D Laplace transforms. In a second series of investigations, dynamic readout from a cross-beam volume hologram recorded with two orthogonal uniform plane waves is considered for various dependences of the refractive index modulation with intensity. Typically, refractive index profiles that are proportional to the …

Map Estimation For Hyperspectral Image Resolution Enhancement Using An Auxiliary Sensor, Russell C. Hardie, Michael T. Eismann, Gregory L. Wilson

Electrical and Computer Engineering Faculty Publications

This paper presents a novel maximum a posteriori (MAP) estimator for enhancing the spatial resolution of an image using co-registered high spatial-resolution imagery from an auxiliary sensor. Here we focus on the use of high-resolution panchomatic data to enhance hyperspectral imagery. However, the estimation framework developed allows for any number of spectral bands in the primary and auxiliary image. The proposed technique is suitable for applications where some correlation, either localized or global, exists between the auxiliary image and the image being enhanced. To exploit localized correlations, a spatially varying statistical model, based on vector quantization, is used. Another important …

Volume Holographic Optical Elements, Ching-Cherng Sun, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

The final two papers are concerned with the analysis of novel holograms. Banerjee et al. investigate holographic recording and reconstruction for edge-lit holograms recorded in a 90-degree geometry. Various cases of recording and readout that incorporate propagational diffraction have been modeled. It is shown that the 90-degree geometry can result in beam shaping, as evidenced through preliminary experimental results with photorefractive lithium niobate. Nguyen et al. propose a new approach for designing computer-generated holograms. An artificial neural network is used to initiate the genetic algorithm so that the high computation cost of genetic algorithms for synthesizing holograms is significantly reduced …

Power-Stepped Protocol: Enhancing Spatial Utilization In A Clustered Mobile Ad Hoc Network, Chansu Yu, Kang G. Shin, Ben Lee

Electrical and Computer Engineering Faculty Publications

While most previous studies on mobile ad hoc networks (MANETs) rely on the assumption that nodes are randomly distributed in the network coverage area, this assumption is unlikely to hold, as nodes tend to be cluttered around hot spots like the site of an accident or disaster. We refer to this as a clustered layout. Intuitively, a MANET with the clustered layout may suffer from serious performance degradation due to the excessive collisions in congested hot spots and space underutilization of sparse areas. In this paper, we propose a power-controlled network protocol, called the power-stepped protocol (PSP), that maximizes the …

Satellite Attitude Control System Design Using Reaction Wheels, Bhanu Gouda, Brian Fast, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

No abstract provided.

Controller Tuning For Dc Motor Speed Control Using Genetic Algorithms, Saurabh Jain, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

No abstract provided.

Kalman Filtering With Uncertain Noise Covariances, Srikiran Kosanam, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

In this paper the robustness of Kalman filtering against uncertainties in process and measurement noise covariances is discussed. It is shown that a standard Kalman filter may not be robust enough if the process and measurement noise covariances are changed. A new filter is proposed which addresses the uncertainties in process and measurement noise covariances and gives better results than the standard Kalman filter. This new filter is used in simulation to estimate the health parameters of an aircraft gas turbine engine.

Synchronous Motor Phase Control By Vector Addition Of Induced Winding Voltages, Daniel J. Simon, Dennis L. Feucht

Electrical and Computer Engineering Faculty Publications

We propose a simple low-cost approach to the winding-sensed control of three-phase synchronous permanent-magnet motors. Our approach results from a straightforward but elegant application of vector-based motor theory. The method therefore does not depend on the differential equations that describe the motor dynamics, and it does not depend on the particular motor parameters. The single method we derive applies to both wye- and delta-configured motors. We vectorially sum the voltage waveforms at the motor terminals in a certain way and use their zero crossings to produce a correctly phased six-step switch sequence. We discuss the implementation for both wye- and …

Data Smoothing And Interpolation Using Eighth-Order Algebraic Splines, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

A new type of algebraic spline is used to derive a filter for smoothing or interpolating discrete data points. The spline is dependent on control parameters that specify the relative importance of data fitting and the derivatives of the spline. A general spline of arbitrary order is first formulated using matrix equations. We then focus on eighth-order splines because of the continuity of their first three derivatives (desirable for motor and robotics applications). The spline's matrix equations are rewritten to give a recursive filter that can be implemented in real time for lengthy data sequences. The filter is lowpass with …

Energy Efficient Routing Protocols For Mobile Ad Hoc Networks, Chansu Yu, Ben Lee, Hee Yong Youn

Electrical and Computer Engineering Faculty Publications

Although establishing correct and efficient routes is an important design issue in mobile ad hoc networks (MANETs), a more challenging goal is to provide energy efficient routes because mobile nodes' operation time is the most critical limiting factor. This article surveys and classifies the energy-aware routing protocols proposed for MANETs. They minimize either the active communication energy required to transmit or receive packets or the inactive energy consumed when a mobile node stays idle but listens to the wireless medium for any possible communication requests from other nodes. Transmission power control approach and load distribution approach belong to the former …

Oci-Based Group Communication Support In Corba, Dongman Lee, Dukyun Nam, Hee Yong Youn, Chansu Yu

Electrical and Computer Engineering Faculty Publications

Group communication is a useful mechanism guaranteeing consistency among replicated objects. The existing approaches do not allow transparent plug-in of group communication protocols into CORBA. They either require modification of CORBA or OS, or provide no room for incorporating group communication transport protocols into CORBA. We thus propose a generic group communication framework that allows transparent plug-in of various group communication protocols with no modification of existing CORBA. We extend the open communications interface (OCI) to support interoperability, reusability of existing group communication, and independency on ORB and OS. We also define the group communication inter-ORB protocol (GCIOP) as a …

Kalman Filtering For Fuzzy Discrete Time Dynamic Systems, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

This paper uses Kalman filter theory to design a state estimator for noisy discrete time Takagi–Sugeno (T–S) fuzzy models. One local filter is designed for each local linear model using standard Kalman filter theory. Steady state solutions can be found for each of the local filters. Then a linear combination of the local filters is used to derive a global filter. The local filters are time-invariant, which greatly reduces the computational complexity of the global filter. The global filter is shown to be unbiased and (under certain conditions) stable. In addition, under the approximation of uncorrelatedness among the local models, …

Examination Of Focused Beam Propagation Through A Finite Non-Reciprocal Planar Chiral Slab Using Complex Fresnel Coefficients And Dual Transforms, Monish Ranjan Chatterjee, Sumit Nema, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

Recently, uniform plane wave propagation across a nonchiral-chiral interface was examined via the development of appropriate Fresnel coefficients. In this extension, propagation of focused uniform and profiled beams through a finite, planar nonreciprocal chiral slab is investigated using complex Fresnel coefficients via angular plane wave decomposition and dual transforms.

M-Ary Amplitude Shift Keying Ofdm System, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

Coherent M-ary amplitude-shift keying (MASK) is proposed for use in orthogonal frequency-division multiplexing (OFDM) systems. The frequency separation between subcarriers is only 1/2T instead of 1/T. With a slightly wider bandwidth, an √M-ary ASK OFDM can achieve the same bit-error rate (BER) of M-ary quadrature amplitude modulation (QAM) OFDM and a better BER than that of M-ary phase-shift keying (MPSK) OFDM. The √M-ary ASK OFDM has the same peak-to-average-power ratio as that of the M-ary QAM OFDM. The MASK OFDM can be implemented digitally and efficiently by fast cosine transform and demodulated by inverse fast cosine transform. Comparisons show that …

A Novel Method For Measuring Induction Machine Magnetizing Inductance, Ana Vladan Stankovic, Eric L. Benedict, Vinod John, Thomas A. Lipo

Electrical and Computer Engineering Faculty Publications

This paper presents a novel method for measuring the magnetizing inductance of an induction machine. The approach uses a static DC excitation technique which can be employed whenever the neutral of the machine is accessible. The proposed method measures only the magnetizing inductance and not the self inductance which normally includes the effect of the stator leakage inductance. Because this test uses a DC excitation, the iron losses in the motor are considerably reduced as well and minimally influence the measurement when compared to the traditional 60-Hz no-load test. By using the proposed method for measuring only the magnetizing inductance, …

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

Electrical and Computer Engineering Faculty Publications

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, …

Aircraft Turbofan Engine Health Estimation Using Constrained Kalman Filtering, Daniel J. Simon, D. L. Simon

Electrical and Computer Engineering Faculty Publications

No abstract provided.

Real-Time Image Analysis Of Living Cellular-Biology Measurements Of Intelligent Chemistry, J.C. Solinsky, Scott E. Budge, P.D. Majors, B. Rex

Electrical and Computer Engineering Faculty Publications

This paper reports on the Pacific Northwest National Laboratory (PNNL) DOE Initiative in Image Science and Technology (ISAT) research, which is developing algorithms and software tool sets for remote sensing and biological applications. In particular, the PNNL ISAT work is applying these research results to the automated analysis of real-time cellular biology imagery to assist the biologist in determining the correct data collection region for the current state of a conglomerate of living cells in three-dimensional motion. The real-time computation of the typical 120 MB/sec multi-spectral data sets is executed in a Field Programmable Gate Array (FPGA) technology, which has …

Coding, Decoding, And Recovery Of Clock Synchronization In Digital Multiplexing System, Hansheng Wang, Xiaoyi Qin, Lieguang Zeng, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

High-speed broadband digital communication networks rely on digital multiplexing technology where clock synchronization, including processing, transmission, and recovery of the clock, is the critical technique. This paper interprets the process of clock synchronization in multiplexing systems as quantizing and coding the information of clock synchronization, interprets clock justification as timing sigma-delta modulation (TΔ-ΣM), and interprets the jitter of justification as quantization error. As a result, decreasing the quantization error is equivalent to decreasing the jitter of justification. Using this theory, the paper studies the existing jitter-reducing techniques in transmitters and receivers, presents some techniques that can decrease the quantization error …

Isomorphic Strategy For Processor Allocation In K-Ary N-Cube Systems, Moonsoo Kang, Chansu Yu, Hee Yong Youn, Ben Lee, Myungchul Kim

Electrical and Computer Engineering Faculty Publications

Due to its topological generality and flexibility, the k-ary n-cube architecture has been actively researched for various applications. However, the processor allocation problem has not been adequately addressed for the k-ary n-cube architecture, even though it has been studied extensively for hypercubes and meshes. The earlier k-ary n-cube allocation schemes based on conventional slice partitioning suffer from internal fragmentation of processors. In contrast, algorithms based on job-based partitioning alleviate the fragmentation problem but require higher time complexity. This paper proposes a new allocation scheme based on isomorphic partitioning, where the processor space is partitioned into higher dimensional isomorphic subcubes. The …

Corp - A Method Of Concatenation And Optimization For Resource Reservation Path In Mobile Internet, Kyounghee Lee, Myungchul Kim, Samuel T. Chanson, Chansu Yu, Jonghyun Lee

Electrical and Computer Engineering Faculty Publications

Existing research related to RSVP with mobility support has mainly focused on maintaining reservation state along the routing path, which changes continuously with the movements of mobile host (MH), without much overhead and delay. However, problems such as deepening RSVP's inherent scalability problem and requiring significant changes in the existing network infrastructure have not been adequately addressed. In this paper, we propose a new approach, known as Concatenation and Optimization for Reservation Path (CORP), which addresses these issues. In CORP, each BS pre-establishes pseudo reservations to its neighboring BSs in anticipation of the MH's movement. When the MH moves into …

An All-Digital Clock-Smoothing Technique—Counting-Prognostication, Xiaoyi Qin, Hansheng Wang, Lieguang Zeng, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

This article presents a novel universal all-digital clock-smoothing technique - counting-prognostication. Operation principles, performance analysis, and comparisons are given. Analysis and measurement results show that this technique can efficiently smooth jitter and wander for a wide pull-in range and pull-out range, and jitter accumulation is small. A cycle-varying counting-prognostication method, which decreases pull-in time, is also suggested.

Digital Image Processing, Russell C. Hardie, Majeed M. Hayat

Electrical and Computer Engineering Faculty Publications

In recent years, digital images and digital image processing have become part of everyday life. This growth has been primarily fueled by advances in digital computers and the advent and growth of the Internet. Furthermore, commercially available digital cameras, scanners, and other equipment for acquiring, storing, and displaying digital imagery have become very inexpensive and increasingly powerful. An excellent treatment of digital images and digital image processing can be found in Ref. [1]. A digital image is simply a two-dimensional array of finite-precision numerical values called picture elements (or pixels). Thus a digital image is a spatially discrete (or discrete-space) …

Bit-Level Erasure Decoding Of Reed-Solomon Codes Over Gf(2/Sup M/), T.K. Moon, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

The algorithms for bit-level erasure decoding of (n,k) Reed-Solomon codes over GF(2/sup m/) beyond the design erasure decoding distance of n-k are considered. Erasure decoding takes place in the (mk, nk) binary image code. When the number of erasures exceeds n-k, then additional parity check equations must be developed. We describe how these equations are obtained and some of their properties. Decoding algorithms are discussed which tradeoff decoding performance for computational complexity. Simulation results for several families of codes are presented which provide information about good binary image codes.

Frequency-Hopped Multiple-Access Communications With Noncoherent M-Ary Ofdm-Ask, A. Al-Dweik, Fuqin Xiong

Electrical and Computer Engineering Faculty Publications

A noncoherent, bandwidth-efficient modulation scheme is proposed for frequency-hopping multiple-access (FH-MA) networks. The proposed scheme is a combination of noncoherent M-ary amplitude-shift keying (NMASK) and orthogonal frequency-division multiplexing (OFDM). Using this scheme minimizes the required data bandwidth. The number of frequency slots available to the users increases significantly for a fixed spread-spectrum bandwidth (BW_SS). The effect of the multiple-access interference is reduced. Simple and accurate bit error rate expressions have been derived for FH-OFDM-MASK in additive white Gaussian noise channels and for FH-OFDM-ASK in Rayleigh fading channels.

Training Fuzzy Systems With The Extended Kalman Filter, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

The generation of membership functions for fuzzy systems is a challenging problem. We show that for Mamdani-type fuzzy systems with correlation-product inference, centroid defuzzification, and triangular membership functions, optimizing the membership functions can be viewed as an identification problem for a nonlinear dynamic system. This identification problem can be solved with an extended Kalman filter. We describe the algorithm and compare it with gradient descent and with adaptive neuro-fuzzy inference system (ANFIS) based optimization of fuzzy membership functions. The methods discussed in this paper are illustrated on a fuzzy filter for motor winding current estimation, and are compared with Butterworth …

Training Radial Basis Neural Networks With The Extended Kalman Filter, Daniel J. Simon

Electrical and Computer Engineering Faculty Publications

Radial basis function (RBF) neural networks provide attractive possibilities for solving signal processing and pattern classification problems. Several algorithms have been proposed for choosing the RBF prototypes and training the network. The selection of the RBF prototypes and the network weights can be viewed as a system identification problem. As such, this paper proposes the use of the extended Kalman filter for the learning procedure. After the user chooses how many prototypes to include in the network, the Kalman filter simultaneously solves for the prototype vectors and the weight matrix. A decoupled extended Kalman filter is then proposed in order …

Sum Normal Optimization Of Fuzzy Membership Functions, 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 certain shape (e.g., triangles or trapezoids) then each membership function can be parameterized by a small number of variables and the membership optimization problem can be reduced to a parameter optimization problem. This is the approach that is typically taken, but it results in membership functions that are not (in general) sum normal. That is, the resulting membership function values do not add up to one at each point in the domain. This …

From Linear To Nonlinear Control Means: A Practical Progression, Zhiqiang Gao

Electrical and Computer Engineering Faculty Publications

With the rapid advance of digital control hardware, it is time to take the simple but effective proportional-integral-derivative (PID) control technology to the next level of performance and robustness. For this purpose, a nonlinear PID and active disturbance rejection framework are introduced in this paper. It complements the existing theory in that (1) it actively and systematically explores the use of nonlinear control mechanisms for better performance, even for linear plants; (2) it represents a control strategy that is rather independent of mathematical models of the plants, thus achieving inherent robustness and reducing design complexity. Stability analysis, as well as …

A Stable Self-Tuning Fuzzy Logic Control System For Industrial Temperature Regulation, Zhiqiang Gao, Thomas A. Trautzsch, James G. Dawson

Electrical and Computer Engineering Faculty Publications

A closed-loop control system incorporating fuzzy logic has been developed for a class of industrial temperature control problems. A unique fuzzy logic controller (FLC) structure with an efficient realization and a small rule base that can be easily implemented in existing industrial controllers was proposed. The potential of FLC in both software simulation and hardware test in an industrial setting was demonstrated. This includes compensating for thermo mass changes in the system, dealing with unknown and variable delays, operating at very different temperature set points without retuning, etc. It is achieved by implementing, in the FLC, a classical control strategy …