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Minimization Of Power Dissipation In Digital Circuits Using Pipelining And A Study Of Clock Gating Technique, Ranganath Panchangam Jan 2004

Minimization Of Power Dissipation In Digital Circuits Using Pipelining And A Study Of Clock Gating Technique, Ranganath Panchangam

Electronic Theses and Dissertations

Power dissipation is one of the major design issues of digital circuits. The power dissipated by a circuit affects its speed and performance. Multiplier is one of the most commonly used circuits in the digital devices. There are various types of multipliers available depending upon the application in which they are used. In the present thesis report, the importance of power dissipation in today's digital technology is discussed and the various types and sources of power dissipation have been elaborated. Different types of multipliers have been designed which vary in their structure and amount of power dissipation. The concept of …

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Autonomous Environmental Mapping In Multi-Agent Uav Systems, Linus Jan Luotsinen Jan 2004

Autonomous Environmental Mapping In Multi-Agent Uav Systems, Linus Jan Luotsinen

Electronic Theses and Dissertations

UAV units are by many researchers and aviation specialists considered the future and cutting edge of modern flight technology. This thesis discusses methods for efficient autonomous environmental mapping in a multi-agent domain. An algorithm that emphasizes on team work by sharing the agents local map information and exploration intentions is presented as a solution to the mapping problem. General theories on how to model and implement rational autonomous behaviour for UAV agents are presented. Three different human and tactical behaviour modeling techniques are evaluated. The author found the CxBR paradigm to be the most interesting approach. Also, in order to …

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Cryptarray A Scalable And Reconfigurable Architecture For Cryptographic Applications, Michael John Lomonaco Jan 2004

Cryptarray A Scalable And Reconfigurable Architecture For Cryptographic Applications, Michael John Lomonaco

Electronic Theses and Dissertations

Cryptography is increasingly viewed as a critical technology to fulfill the requirements of security and authentication for information exchange between Internet applications. However, software implementations of cryptographic applications are unable to support the quality of service from a bandwidth perspective required by most Internet applications. As a result, various hardware implementations, from Application-Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), to programmable processors, were proposed to improve this inadequate quality of service. Although these implementations provide performances that are considered better than those produced by software implementations, they still fall short of addressing the bandwidth requirements of most cryptographic applications …

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Performance Analysis Of Low-Power, Short-Range Wireless Transceivers, Usha Neupane Jan 2004

Performance Analysis Of Low-Power, Short-Range Wireless Transceivers, Usha Neupane

Electronic Theses and Dissertations

To address the various emerging standards like BluetoothTM, Home RF, Wi-fiTM (IEEE 802.11), ZigBeeTM etc., in the field of wireless communications, different transceivers have been designed to operate at various frequencies such as 450 MHz, 902-920 MHz, 2.4 GHz, all part of designated ISM band. Though, the wireless systems have become more reliable, compact and easy to develop than before, a detailed performance analysis and characterization of the devices should be done. This report details the performance analysis and characterization of a popular binary FSK transceiver TRF6901 from Texas Instruments. The performance analysis of the device is done with respect …

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Effects Of Deposition Temperature And Post Deposition Annealing On The Electrical Properties Of Barium Strontium Titanate Thin Film For Embedded Capacitor Applications, Ranganathan, Ravip Peelamedu Jan 2004

Effects Of Deposition Temperature And Post Deposition Annealing On The Electrical Properties Of Barium Strontium Titanate Thin Film For Embedded Capacitor Applications, Ranganathan, Ravip Peelamedu

Electronic Theses and Dissertations

A higher degree of system level integration can be achieved by integrating the passive components into semiconductor devices, which seem to be an enabling technology for portable communication and modern electronic devices. Greater functionality, higher performance and increase in reliability can be achieved by miniaturizing and reducing the number of components in integrated circuits. The functional potential of small electronic devices can be enormously increased by implementing the embedded capacitors, resistors and inductors. This would free up surface real estate allowing either a smaller footprint or more silicon devices to be placed on the same sized substrate. This thesis focuses …

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Ubiquitous Map-Image Access Through Wireless Overlay Networks, Jianfei Cai, Haijie Huang, Zefeng Ni, Chang Wen Chen Jan 2004

Ubiquitous Map-Image Access Through Wireless Overlay Networks, Jianfei Cai, Haijie Huang, Zefeng Ni, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

With the availability of various wireless link-layer technologies, such as Bluetooth, WLAN and GPRS, in one wireless device, ubiquitous communications can be realized through managing vertical handoff in the environment of wireless overlay networks. In this paper, we propose a vertical handoff management system based on mobile IPv6, which can automatically manage the multiple network interfaces on the mobile device, and make decisions on network interface selection according to the current situation. Moreover, we apply our proposed vertical handoff management with JPEG-2000 codec to the wireless application of map image access. The developed system is able to provide seamless communications, …

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Finite Element Analysis Of Left-Handed Waveguides, Balasubramaniam, Vellakkinar Jan 2004

Finite Element Analysis Of Left-Handed Waveguides, Balasubramaniam, Vellakkinar

Electronic Theses and Dissertations

In this work, waveguides with simultaneous negative dielectric permittivity and magnetic permeability, otherwise known as left-handed waveguides, are investigated. An approach of formulating and solving an eigenvalue problem with finite element method resulting in the dispersion relation of the waveguides is adopted in the analysis. Detailed methodology of one-dimensional scalar and two-dimensional vector finite element formulation for the analysis of grounded slab and arbitrary shaped waveguides is presented. Based on the analysis, for waveguides with conventional media, excellent agreement of results is observed between the finite element approach and the traditional approach. The method is then applied to analyze left-handed …

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Dynamic Spill Monitoring: A Coordinated Approach, Peter Jones, James K. Archibald, Randal Beard, Matthew Blake Jan 2004

Dynamic Spill Monitoring: A Coordinated Approach, Peter Jones, James K. Archibald, Randal Beard, Matthew Blake

Faculty Publications

Sponsorship: INEEL. This paper presents a coordinated control strategy for autonomous monitoring of a dynamically changing hazardous spill. The control strategy is a two level hierarchy that uses use coordination variables to communicate between the levels. The upper level is a resource allocator. The lower level consists of several "commanders" each with a possibly different objective. A physical description of the problem is given, as well as the methods of spill modeling and simulation. Tactics for locating, gravitating to and circling the spill are presented. Finally, both simulation and hardware results are given.

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Wideband Channel Model For Aeronautical Telemetry, Christian Bettweiser, Adam Davis, Michael D. Rice Jan 2004

Wideband Channel Model For Aeronautical Telemetry, Christian Bettweiser, Adam Davis, Michael D. Rice

Faculty Publications

A multipath channel model for wideband aeronautical telemetry links is presented. Channel sounding data were collected at Edwards AFB, CA, at both L-band and lower S-band. Frequency domain analysis techniques were used to evaluate candidate channel models. The channel model is composed of three propagation paths: a line-of-sight direct path and two specular reflections. The first specular reflection is characterized by a relative amplitude of 70% to 96% of the line-of-sight amplitude and a delay of 10—80 ns. This path is the result of “ground bounces” off the dry lake bed at Edwards and is a typical terrain feature at …

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A Fast And Simple Algorithm For Computing M-Shortest Paths In State Graph, M. Sherwood, Laxmi P. Gewali, Henry Selvaraj, Venkatesan Muthukumar Jan 2004

A Fast And Simple Algorithm For Computing M-Shortest Paths In State Graph, M. Sherwood, Laxmi P. Gewali, Henry Selvaraj, Venkatesan Muthukumar

Electrical & Computer Engineering Faculty Research

We consider the problem of computing m shortest paths between a source node s and a target node t in a stage graph. Polynomial time algorithms known to solve this problem use complicated data structures. This paper proposes a very simple algorithm for computing all m shortest paths in a stage graph efficiently. The proposed algorithm does not use any complicated data structure and can be implemented in a straightforward way by using only array data structure. This problem appears as a sub-problem for planning risk reduced multiple k-legged trajectories for aerial vehicles.

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Determination Of The Phase Of A Transfer Function: Theory Versus Practice, Pauline Sourdille, Aidan O'Dwyer Jan 2004

Determination Of The Phase Of A Transfer Function: Theory Versus Practice, Pauline Sourdille, Aidan O'Dwyer

Conference papers

In control systems, a way to evaluate the stability of a system is to determine the magnitude and phase of the open loop system transfer function in the frequency domain. But due to the nature of the phase expression, practice and theory are not aligned. Some problems arise when the phase is determined, caused by the properties of the arctan function. This paper analyses these phase problems for a third order lag system and a third order lag with time delay system. It also presents modifications to obtain the analytically correct phase values from the computed values.

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A Wireless Traffic Probe For Radio Resource Management And Qos Provisioning In Ieee 802.11 Wlans, Mark Davis Jan 2004

A Wireless Traffic Probe For Radio Resource Management And Qos Provisioning In Ieee 802.11 Wlans, Mark Davis

Conference papers

The emergence of real-time services such as voice over IP (VoIP) and video streaming imposes stringent requirements on the performance of a network if quality of service (QoS) targets are to be achieved. In the case of wireless networks, some form of radio resource management (RRM) is typically required to allocate the available resources among the contending stations in accordance with their needs and respective priorities. A critical aspect of any RRM scheme is the ability to monitor resource usage and to determine the resource requirements on a per-station basis. In this paper we describe a wireless traffic probe for …

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Power Coupling Between Two Step-Index Multimode Fibers Of Different Numerical Apertures With An Angular Misalignment, Cheng Gao, Gerald Farrell Jan 2004

Power Coupling Between Two Step-Index Multimode Fibers Of Different Numerical Apertures With An Angular Misalignment, Cheng Gao, Gerald Farrell

Articles

Coupling efficiency between two step- index multimode fibers of different numerical aper- tures with an angular misalignment is calculated. The theory is presented using radiometry and geometrical optics. The limit case of the calculation is consistent with a previously published result. The results may be useful for applications such as power launching between two types of fibers with different numerical apertures for example silica fiber and plastic optical fiber(POF) and with an angular misalignment.

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The 7 C'S For Creating Living Software: A Research Perspective For Quality-Oriented Software Engineering, Mehmet Akşi̇t Jan 2004

The 7 C'S For Creating Living Software: A Research Perspective For Quality-Oriented Software Engineering, Mehmet Akşi̇t

Turkish Journal of Electrical Engineering and Computer Sciences

This article proposes the 7 C's for realizing quality-oriented software engineering practices. All the desired qualities of this approach are expressed in short by the term living software. The 7 C's are: Concern-oriented processes, Canonical models, Composable models, Certifiable models, Constructible models, Closure property of models and Controllable models. Each C is explained by the help of a set of definitions, a short overview of the background work and the problems that software engineers may experience in realizing the corresponding C. Further, throughout the article, a software development example is presented for illustrating the realization of the 7 C's. Finally, …

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A Platform For Software Engineering Course Projects, Bi̇rol Aygün Jan 2004

A Platform For Software Engineering Course Projects, Bi̇rol Aygün

Turkish Journal of Electrical Engineering and Computer Sciences

The importance of projects in software engineering courses is well known. Both synthetic and real-life projects have various advantages and disadvantages. Our aim was to create a framework where students can develop projects which reflect some of the complexities of real-life, involving many concurrent, interacting, asynchronous processes, each in a different stage of development, with wide temporal differences among them - some occurring within millisconds of each other and others executing sporadically over much longer periods. In this project, which was carried out in different arrangements in several software engineering courses in three universities, the students developed both the sub- …

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A Pattern Based Approach To Web Design Formalization, Ahmet Sikici, Yasemi̇n Topaloğlu Jan 2004

A Pattern Based Approach To Web Design Formalization, Ahmet Sikici, Yasemi̇n Topaloğlu

Turkish Journal of Electrical Engineering and Computer Sciences

World Wide Web is a global information network that affects many fields of our lives. The distributed, interlinked, visual and heterogeneous structure of the web makes it an irregular development environment. In this paper we propose a pattern based approach for increasing the effectiveness of development for the Web environment. This approach is based on the representation of the core meaning of each design as a set of patterns and requires the formulation of abstract solutions in a mathematical precision. This way not only reusable design experience will be codified unambiguously, but a smooth transition between the design and implementation …

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A Robustness Analysis Of Game-Theoretic Cdma Power Control, Xingzhe Fan, Murat Arcak, John T. Wen Jan 2004

A Robustness Analysis Of Game-Theoretic Cdma Power Control, Xingzhe Fan, Murat Arcak, John T. Wen

Turkish Journal of Electrical Engineering and Computer Sciences

This paper studies robustness of a gradient-type CDMA uplink power control algorithm with respect to disturbances and time-delays. This problem is of practical importance because unmodeled secondary interference effects from neighboring cells play the role of disturbances, and propagation delays are ubiquitous in wireless data networks. We first show L_p-stability, for p \in [1,\infity], with respect to additive disturbances. We pursue L_{\infity}-stability within the input-to-state stability (ISS) framework of Sontag [7], which makes explicit the vanishing effect of the initial conditions. Next, using the ISS property and a loop transformation, we prove that global asymptotic stability is preserved for sufficiently …

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Global Stability Analysis Of An End-To-End Congestion Control Scheme For General Topology Networks With Delay, Tansu Alpcan, Tamer Başar Jan 2004

Global Stability Analysis Of An End-To-End Congestion Control Scheme For General Topology Networks With Delay, Tansu Alpcan, Tamer Başar

Turkish Journal of Electrical Engineering and Computer Sciences

We analyze the stability properties of an end-to-end congestion control scheme under fixed heterogeneous delays, and for general network topologies. The scheme analyzed is based on the congestion control game of [1], with the starting point being the unique Nash equilibrium of that game. We prove global stability of this solution (and hence of the congestion control algorithm) under a mild symmetricity condition. We further demonstrate the stability of the algorithm numerically for various delays, user numbers, and topologies

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Flow Controller Design And Performance Analysis For Self-Similar Network Traffic, Peng Yan Jan 2004

Flow Controller Design And Performance Analysis For Self-Similar Network Traffic, Peng Yan

Turkish Journal of Electrical Engineering and Computer Sciences

Recent studies of high-resolution traffic measurement discovered the self-similarity in both LAN and WAN traffic. In this paper, we introduce a two-degree of freedom rate based flow controller, which includes a robust H^{\infity} control block and an LMMSE based capacity predictor. The former part can guarantee the robust stability against time-varying time delay uncertainties and the latter improves the transient response by predicting the self-similar cross-traffic. Implementation issues are discussed and performance analysis is provided to validate our design. We also investigate the prediction and control in larger time scale which is more applicable for the real network environment

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Exact Synthesis Of 3-Qubit Quantum Circuits From Non-Binary Quantum Gates Using Multiple-Valued Logic And Group Theory, Guowu Yang, William N. N. Hung, Xiaoyu Song, Marek Perkowski Jan 2004

Exact Synthesis Of 3-Qubit Quantum Circuits From Non-Binary Quantum Gates Using Multiple-Valued Logic And Group Theory, Guowu Yang, William N. N. Hung, Xiaoyu Song, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

We propose an approach to optimally synthesize quantum circuits from non-permutative quantum gates such as Controlled-Square-Root–of-Not (i.e. Controlled-V). Our approach reduces the synthesis problem to multiple-valued optimization and uses group theory. We devise a novel technique that transforms the quantum logic synthesis problem from a multi-valued constrained optimization problem to a permutable representation. The transformation enables us to utilize group theory to exploit the symmetric properties of the synthesis problem. Assuming a cost of one for each two-qubit gate, we found all reversible circuits with quantum costs of 4, 5, 6, etc, and give another algorithm to realize these reversible …

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Forecasting The Onset Of Cloud-Ground Lightning Using S-Pol And Nldn Data, Kartik Ramakrishnan Jan 2004

Forecasting The Onset Of Cloud-Ground Lightning Using S-Pol And Nldn Data, Kartik Ramakrishnan

Electronic Theses and Dissertations

The maximum number of thunderstorms in the United States occur in Central Florida. The cloud-ground lightning from these storms is responsible for extensive damage to life and property. The lightning from these storms is also responsible for delays and cancellations of space shuttle launch attempts at the Kennedy Space Center (KSC) and the 45th Space Wing unmanned launches at Cape Canaveral launch facilities. For these and other reasons accurate forecasting of cloud-ground lightning is of crucial importance. The second phase of NASA's Tropical Rainfall Measuring Mission Texas and Florida Underflights project (TEFLUN-B) was conducted between 1st August and 30th September, …

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Sub-Optimal Ultra-Wide Band Receivers, Nilesh Bhuvanendran Jan 2004

Sub-Optimal Ultra-Wide Band Receivers, Nilesh Bhuvanendran

Electronic Theses and Dissertations

Ultra-wide Band (UWB) has sparked a lot of interest lately from the industry and academia. The growing capacity of the wireless industry is requires a new communication system that satisfies the high data rate which does not interfere with existing RF systems. UWB promises to be this new technology. UWB also promises low power, low cost and flexibility. The UWB Channel opens up a huge new wireless channel with Giga Hertz Capacities as well as the highest spatial capacities measured in bits per hertz per square meter. When properly implemented UWB channel can share spectrum with traditional radio systems without …

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Nonlinear Adaptive Estimation Andits Application To Synchronization Of Lorenz System, Yufang Jin Jan 2004

Nonlinear Adaptive Estimation Andits Application To Synchronization Of Lorenz System, Yufang Jin

Electronic Theses and Dissertations

Synchronization and estimation of unknown constant parameters for Lorenz-type transmitter are studied under the assumption that one of the three state variables is not transmitted and that transmitter parameters are not known apriori. An adaptive algorithm is proposed to estimate both the state and system parameters. Since Lorenz system shows the property of sensitivity to initial conditions and evolves in different mode with parameter variation, an equivalent system is introduced. The adaptive observer is designed based on this equivalent system without any requirement on initial conditions of the observer. It is shown by Lyapunov arguments and persistent excitation analysis that …

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Dynamic Sensor Management Using Multi Objective Particle Swarm Optimizer, Kalyan Veeramachaneni, Lisa Ann Osadciw Jan 2004

Dynamic Sensor Management Using Multi Objective Particle Swarm Optimizer, Kalyan Veeramachaneni, Lisa Ann Osadciw

Electrical Engineering and Computer Science - All Scholarship

This paper presents a Swarm Intelligence based approach for sensor management of a multi sensor networks. Alternate sensor configurations and fusion strategies are evaluated by swarm agents, and an optimum configuration and fusion strategy evolves. An evolutionary algorithm, particle swarm optimization, is modified to optimize two objectives: accuracy and time. The output of the algorithm is the choice of sensors, individual sensor's thresholds and the optimal decision fusion rule. The results achieved show the capability of the algorithm in selecting optimal configuration for a given requirement consisting of multiple objectives.

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Solution Of Time Domain Pmchw Formulation For Transient Electromagnetic Scattering From Arbitrarily Shaped 3-D Dielectric Objects, Baek Ho Jung, T. K. Sarkar, Y.-S. Chung Jan 2004

Solution Of Time Domain Pmchw Formulation For Transient Electromagnetic Scattering From Arbitrarily Shaped 3-D Dielectric Objects, Baek Ho Jung, T. K. Sarkar, Y.-S. Chung

Electrical Engineering and Computer Science - All Scholarship

In this paper, we analyze the transient electromagnetic response from three-dimensional (3-D) dielectric bodies using a time domain PMCHW (Poggio, Miller, Chang, Harrington, Wu) integral equation. The solution method in this paper is based on the Galerkin’s method that involves separate spatial and temporal testing procedures. Triangular patch basis functions are used for spatial expansion and testing functions for arbitrarily shaped 3-D dielectric structures. The time domain unknown coefficients of the equivalent electric and magnetic currents are approximated by a set of orthonormal basis functions that are derived from the Laguerre functions. These basis functions are also used as the …

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Design And Hardware Implementation Of A Novel Scrambling Security Algorithm For Robust Wireless Local Area Networks, Mohit Jagetia Jan 2004

Design And Hardware Implementation Of A Novel Scrambling Security Algorithm For Robust Wireless Local Area Networks, Mohit Jagetia

Electronic Theses and Dissertations

The IEEE802.11 standard for wireless networks includes a Wired Equivalent Privacy (WEP) protocol, which is a popular wireless secure communication stream cipher protocol approach to network security used to protect link-layer communications from eavesdropping and other attacks. It allows user to communicate with the user; sharing the public key over a network. It provides authentication and encrypted communications over unsecured channels. However, WEP protocol has an inherent security flaw. It is vulnerable to the various attacks, various experiments has proved that WEP fails to achieve its security goals. This thesis entails designing, evaluating and prototyping a wireless security infrastructure that …

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Modifications To The Fuzzy-Artmap Algorithm For Distributed Learning In Large Data Sets, Jose R. Castro Jan 2004

Modifications To The Fuzzy-Artmap Algorithm For Distributed Learning In Large Data Sets, Jose R. Castro

Electronic Theses and Dissertations

The Fuzzy–ARTMAP (FAM) algorithm has been proven to be one of the premier neural network architectures for classification problems. FAM can learn on line and is usually faster than other neural network approaches. Nevertheless the learning time of FAM can slow down considerably when the size of the training set increases into the hundreds of thousands. In this dissertation we apply data partitioning and network partitioning to the FAM algorithm in a sequential and parallel setting to achieve better convergence time and to efficiently train with large databases (hundreds of thousands of patterns). We implement our parallelization on a Beowulf …

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Gauss-Newton Based Learning For Fully Recurrent Neural Networks, Aniket Arun Vartak Jan 2004

Gauss-Newton Based Learning For Fully Recurrent Neural Networks, Aniket Arun Vartak

Electronic Theses and Dissertations

The thesis discusses a novel off-line and on-line learning approach for Fully Recurrent Neural Networks (FRNNs). The most popular algorithm for training FRNNs, the Real Time Recurrent Learning (RTRL) algorithm, employs the gradient descent technique for finding the optimum weight vectors in the recurrent neural network. Within the framework of the research presented, a new off-line and on-line variation of RTRL is presented, that is based on the Gauss-Newton method. The method itself is an approximate Newton's method tailored to the specific optimization problem, (non-linear least squares), which aims to speed up the process of FRNN training. The new approach …

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Analysis Of Time Synchronization Errors In High Data Rate Ultrawideban, Lakesha Bates Jan 2004

Analysis Of Time Synchronization Errors In High Data Rate Ultrawideban, Lakesha Bates

Electronic Theses and Dissertations

Emerging Ultra Wideband (UWB) Orthogonal Frequency Division Multiplexing (OFDM) systems hold the promise of delivering wireless data at high speeds, exceeding hundreds of megabits per second over typical distances of 10 meters or less. The purpose of this Thesis is to estimate the timing accuracies required with such systems in order to achieve Bit Error Rates (BER) of the order of magnitude of 10-12 and thereby avoid overloading the correction of irreducible errors due to misaligned timing errors to a small absolute number of bits in error in real-time relative to a data rate of hundreds of megabits per second. …

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Design And Implementation Of A Digital Controller With Dsp For Half-Br, Yangyang Wen Jan 2004

Design And Implementation Of A Digital Controller With Dsp For Half-Br, Yangyang Wen

Electronic Theses and Dissertations

DC-DC power converters play an important role in powering telecom and computing systems. With the speed improvement and cost reduction of digital control, digital controller is becoming a trend for DC-DC converters in addition to existed digital monitoring and management technology. In this thesis, digital control is investigated for DC-DC converters applications. To deeply understand the whole control systems, DC-DC converter models are investigated based on averaged state-space modeling. Considering half-bridge isolated DC-DC converter with a current doublers rectifier has advantages over other topologies especially in the application of low-voltage and high-current DC-DC converters, the thesis take it as an …

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