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Design And Implementation Of A 3d Computer Game Controller Using Inertial Mems Sensors, Ali Pezeshk Jan 2004

Design And Implementation Of A 3d Computer Game Controller Using Inertial Mems Sensors, Ali Pezeshk

Dissertations, Master's Theses and Master's Reports - Open

Though 3D computer graphics has seen tremendous advancement in the past two decades, most available mechanisms for computer interaction in 3D are high cost and targeted for industry and virtual reality applications. Recent advances in Micro-Electro-Mechanical-System (MEMS) devices have brought forth a variety of new low-cost, low-power, miniature sensors with high accuracy, which are well suited for hand-held devices. In this work a novel design for a 3D computer game controller using inertial sensors is proposed, and a prototype device based on this design is implemented. The design incorporates MEMS accelerometers and gyroscopes from Analog Devices to measure the three …


Performance Estimation Of A Sip Based Push-To-Talk Service For 3g Wireless Networks, Eoin O'Regan Jan 2004

Performance Estimation Of A Sip Based Push-To-Talk Service For 3g Wireless Networks, Eoin O'Regan

Theses

Push To Talk (PTT) services have been in existence for several decades providing dispatch services via two-way radio such as walkie-talkies. For a number of years now PTT services have been available for use over mobile phone networks. These mobile PTT services have occupied a niche market with business users and have been provided on proprietary networks that do not enable roaming.

Over the past year there has been an explosion of interest in the concept of PTT provided over mobile networks using Internet Protocol (IP) technology. This service uses cellular access and radio resources more efficiently than circuit-switched cellular …


Delivery Of Wireless Ad Hoc Services Using Jini, Sinead Cummins Jan 2004

Delivery Of Wireless Ad Hoc Services Using Jini, Sinead Cummins

Theses

Traditionally, networks were planned infrastructures consisting mainly ot desktop machines and servers. As a result of the careful planning carried out prior to their construction, these networks were easily managed and controlled by network administrators. Today these networks are joined by cell phones, PDAs and other handheld devices as well as a host of sensors. This has led to a migration from traditional networks to ad hoc networks.

One way to envisage what this new environment will be like is to imagine what life will be like at the edge of the network. Today the edge mostly consists ot clients …


Cmos Digital Pixel Sensor Array With Time Domain Analogue To Digital Conversion, Alistair J. Kitchen Jan 2004

Cmos Digital Pixel Sensor Array With Time Domain Analogue To Digital Conversion, Alistair J. Kitchen

Theses: Doctorates and Masters

This thesis presents a digital pixel sensor array, which is the first stage of an ongoing project to produce a CMOS image sensor with on-chip image processing. The analogue to digital conversion is performed at the pixel level, with the result stored in pixel memory. This architecture allows fast, reliable access to the image data and simplifies the integration of the image array and the processing logic. Each pixel contains a photodiode sensor, a comparator, memory and addressing logic. The photodiode sensor operates in integrating mode, where the photodiode junction capacitance is first charged to an initial voltage, and then …


Opto-Vlsi Based Wdm Multifunction Device, Selam T. Ahderom Jan 2004

Opto-Vlsi Based Wdm Multifunction Device, Selam T. Ahderom

Theses: Doctorates and Masters

The tremendous expansion of telecommunication services in the past decade, in part due to the growth of the Internet, has made the development of high-bandwidth optical net-works a focus of research interest. The implementation of Dense-Wavelength Division Multiplexing (DWDM) optical fiber transmission systems has the potential to meet this demand. However, crucial components of DWDM networks – add/drop multiplexers, filters, gain equalizers as well as interconnects between optical channels – are currently not implemented as dynamically reconfigurable devices. Electronic cross-connects, the traditional solution to the reconfigurable optical networks, are increasingly not feasible due to the rapidly increasing bandwidth of the …


Implementation Of Arithmetic Primitives Using Truly Deep Submicron Technology (Tdst), Sholeh Eshraghian Jan 2004

Implementation Of Arithmetic Primitives Using Truly Deep Submicron Technology (Tdst), Sholeh Eshraghian

Theses: Doctorates and Masters

The invention of the transistor in 1947 at Bell Laboratories revolutionised the electronics industry and created a powerful platform for emergence of new industries. The quest to increase the number of devices per chip over the last four decades has resulted in rapid transition from Small-Scale-Integration (SSI) and Large-Scale-lntegration (LSI), through to the Very-Large-Scale-Integration (VLSI) technologies, incorporating approximately 10 to 100 million devices per chip. The next phase in this evolution is the Ultra-Large-Scale-Integration (ULSI) aiming to realise new application domains currently not accessible to CMOS technology. Although technology is continuously evolving to produce smaller systems with minimised power dissipation, …


Photonic Rf Signal Processors, Rong Zheng Jan 2004

Photonic Rf Signal Processors, Rong Zheng

Theses: Doctorates and Masters

The purpose of this thesis is to explore the emerging possibilities of processing radiofrequency (RF) or microwave signals in optical domain, which will be a key technology to implement next-generation mobile communication systems and future optical networks. Research activities include design and modelling of novel photonic architectures for processing and filtering of RF, microwave and millimeter wave signals of the above mentioned applications. Investigations especially focus on two basic functions and critical requirements in advanced RF systems, namely: • Interference mitigation and high Q tunable filters. • Arbitrary filter transfer function generation. The thesis begins with a review on several …


Adaptive Applications Of Opto-Vlsi Processors In Wdm Networks, Mehrdad Raisi Jan 2004

Adaptive Applications Of Opto-Vlsi Processors In Wdm Networks, Mehrdad Raisi

Theses: Doctorates and Masters

Communication is an inseparable part of human life and its nature continues to evolve and improve. The advent of laser was a herald to the new possibilities in the communication world. In recent years technologies such as Wavelength Division Multiplexing (WDM) and Erbium Doped Fiber Amplifiers (EDFA) have afforded significant boost to the practice of optical communication. At the heart of this brave new world is the need to dynamically/ adaptively steer/route beams of light carrying very large amounts of data. In recent years many techniques have been proposed for this purpose by various researchers. In this study we have …


Development Of A Low Jitter Multiplying Delay Locked Loop, Ian Kennedy Jan 2004

Development Of A Low Jitter Multiplying Delay Locked Loop, Ian Kennedy

Theses

The clock generator is a critical component in high-speed wireline communication systems. The clocks in these systems mark time at precise regular intervals. Any deviation of the clock edges from these ideal time points is called jitter and it degrades the overall integrity of the communication system. This thesis looks at both phase locked loops (PLLs) and delay locked loops (DLLs) and their ability to provide these precise clocks. Expressions for the thermal noise-induced jitter in both the PLL and DLL are compared. From this, the DLL is shown to possess the potential for better jitter performance. However, to realise …


A Sip Based Multimedia Messaging Service, Donna Griffin Jan 2004

A Sip Based Multimedia Messaging Service, Donna Griffin

Theses

The Session Initiation Protocol (SIP) is the protocol of choice for establishing multimedia sessions in Universal Mobile Telecommunications System (UMTS) networks as stated by 3GPP. SIP is a protocol that will merge together the cellular and Internet worlds and is also scalable, highly available and extensible. It enables mobile carriers to extend operations, administration, maintenance and provisioning (OAMP) in one application to all applications. In addition, while SIP permits presence. Instant Messaging, File Sharing etc., its ultimate value lies in seamlessly aggregating these applications in more powerful offerings, such as Multimedia Messaging, Push to Talk and Voice over IP.

Multimedia …


Enhancement Of Linear Prediction Coefficient Quantisation In The 3g Adaptive Multi Rate Speech Coder, John Raymond Mccarthy Jan 2004

Enhancement Of Linear Prediction Coefficient Quantisation In The 3g Adaptive Multi Rate Speech Coder, John Raymond Mccarthy

Theses

Most speech coding algorithms in use today utilise the source-filter model of human speech production in which speech is modelled as the response of a time varying, linear, all-pole, synthesis filter to an input excitation. In mobile communications, it is the coefficients of this filter and details of the excitation that are transmitted. The filter coefficients are first quantised using a limited number of bits. Due to coefficient sensitivity, direct quantisation of the filter coefficients may lead to an unstable filter during speech synthesis at the receiver and hence an alternative representation is needed. Line Spectral Frequencies (LSFs) have evolved …


Liquid Crystal Based Optical Switches, Yuliya Semenova, S. Dovgalets, Yuri Panarin, Gerald Farrell Jan 2004

Liquid Crystal Based Optical Switches, Yuliya Semenova, S. Dovgalets, Yuri Panarin, Gerald Farrell

Articles

Optical switches using two electro-optical effects in liquid crystals are proposed and investigated for incorporation in a switch matrix for optical networks. These two devices employ selective reflection in cholesteric layers and total reflection at the border between glass and nematic liquid crystal. Prototypes of these switches have been designed and their parameters have been investigated. Initial results suggest the switching contrast ratio of 38.5 and 42 dB, respectively, with insertion loss about 2.3…2.9 dB for polarized light.


Implementation Of New Modified Smith Predictor Designs, Pauline Sourdille, Aidan O'Dwyer Jan 2004

Implementation Of New Modified Smith Predictor Designs, Pauline Sourdille, Aidan O'Dwyer

Conference papers

This paper outlines two modified Smith predictors developed previously by the authors and then presents the implementation results of these structures for the control of a pilot scale heating and ventilation system, the PT 326 process trainer from Feedback Instruments Ltd. These results are compared to the results obtained with a Smith predictor structure.


Optimal Control Strategy Of Upqc For Minimum Operational Losses, Malabika Basu, Michael Farrell, Michael Conlon, Kevin Gaughan, Eugene Coyle Jan 2004

Optimal Control Strategy Of Upqc For Minimum Operational Losses, Malabika Basu, Michael Farrell, Michael Conlon, Kevin Gaughan, Eugene Coyle

Conference papers

The paper deals with a new control technique for a unified power quality conditioner (UPQC), which is the most comprehensive of FACTS devices. The problems of power quality continue to gain in significance because of the proliferation of sensitive and harmonic producing loads in electrical networks. Greater awareness among customers with regard to supply integrity and a desire by suppliers to be able to guarantee a certain degree of power quality to customers is being reflected in the development of innovative power quality solutions. The UPQC, which is a combination of shunt and series compensation, is designed to cater for …


Developing Software For Wound Measurement, Savo Kordic Jan 2004

Developing Software For Wound Measurement, Savo Kordic

Theses : Honours

Chronic wounds such as leg ulcers, pressure ulcers and diabetic ulcers affect many thousands of people in Australia. In addition to the costs of these wounds in terms of human suffering, loss of income and resources, there are costs related to the treatment of ulcers. Thus, there is a genuine need to develop an accurate and a fully objective application for wound measurement. The aim of this project was to create software for the measurement of wounds. In achieving this goal, several issues were addressed: an accurate measurement method capable of detecting small changes in an open wound surface area, …


A Taxonomy Of Network Computing Systems, Muthucumaru Maheswaran, Shoukat Ali Jan 2004

A Taxonomy Of Network Computing Systems, Muthucumaru Maheswaran, Shoukat Ali

Electrical and Computer Engineering Faculty Research & Creative Works

Rapid advances in networking and microprocessor technologies have led to the emergence of Internet-wide distributed computing systems ranging from simple LAN-based clusters to planetary-scale networks. As these network computing systems evolve by combining the best features of existing systems, differences among NCs are blurring. To address this problem, researchers have proposed formal taxonomies of NC systems. We propose a new taxonomy that is both broad enough to encompass all NC systems and simple enough to be widely used.


Logic Synthesis For Regular Fabric Realized In Quantum Dot Cellular Automata, Marek Perkowski, Alan Mishchenko Jan 2004

Logic Synthesis For Regular Fabric Realized In Quantum Dot Cellular Automata, Marek Perkowski, Alan Mishchenko

Electrical and Computer Engineering Faculty Publications and Presentations

Quantum Dot Cellular Automata are one of the most prospective nano-technologies to build digital circuits. Because of the requirements of only 2 layer wiring and noise avoidance, realizing the circuit in a regular fabrics is even more important for this technology than for classical technologies. In this paper, we propose a regular layout geometry called 3x3 lattice. The main difference of this geometry compared to the known 2x2 lattices is that it allows the cofactors on a level to propagate to three rather than two nodes on the lower level. This gives additional freedom to synthesize compact functional representations. We …


A New Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Zhong Nie, Ali Emadi Jan 2004

A New Estimative Current Mode Control Technique For Dc-Dc Converters Operating In Discontinuous Conduction Mode, Mehdi Ferdowsi, Zhong Nie, Ali Emadi

Electrical and Computer Engineering Faculty Research & Creative Works

A new digital control technique for power converters operating in discontinuous conduction mode (DCM) is introduced and applied to a boost converter. In contrast to the conventional analogue control methods, the principal idea of this new control scheme is to use real-time analysis and estimate the required on-time of the switch based on the dynamic of the system. The proposed control algorithm can easily be programmed in a digital signal processor (DSP). This novel technique is applicable to any converter operating in DCM including power factor correctors (PFC). However, this work mainly focuses on the boost topology. In this paper, …


Mas-Mom Hybrid Method With Wire's Image Using In Excitation Problems, D. G. Kakulia, David Pommerenke, Kai Xiao, D. D. Karkashadze, K. N. Tavzarashvili, G. N. Ghvedashvili, R. S. Zaridze Jan 2004

Mas-Mom Hybrid Method With Wire's Image Using In Excitation Problems, D. G. Kakulia, David Pommerenke, Kai Xiao, D. D. Karkashadze, K. N. Tavzarashvili, G. N. Ghvedashvili, R. S. Zaridze

Electrical and Computer Engineering Faculty Research & Creative Works

An important class of problems is the interaction of an antenna with the cavity of a semi-open metallic structure. In a working environment, an antenna may change its performance due to interactions with its surroundings. This is especially true in automotive applications. Therefore, it is important to consider the interaction of an antenna with possible resonating parts, and to solve these complex electrodynamics problems together. The development of methods for modeling and studying electromagnetic compatibility (EMC) problems has practical value. The method of auxiliary sources (MAS) with the method of moments (MoM) is applied to solve the excitation problem where …


Experimental Evaluation Of A Nested Microphone Array With Adaptive Noise Cancellers, Y. Rosa Zheng, M. El-Tanany, R. A. Goubran Jan 2004

Experimental Evaluation Of A Nested Microphone Array With Adaptive Noise Cancellers, Y. Rosa Zheng, M. El-Tanany, R. A. Goubran

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a near-field broadband adaptive beamforming scheme for intelligent computer telephony and teleconferencing applications, namely the nested microphone array with adaptive noise canceller (NMA-ANC). The NMA-ANC scheme incorporates an harmonically nested array with a nonuniformly subbanded multirate filter bank. Each subband array employs several near-field delay-filter-and-sum beamformers and an adaptive noise canceller (ANC). The proposed NMA-ANC is evaluated via a noise rejection experiment and dereverberation experiment performed in an anechoic chamber and a real conference room, respectively. The experiment data are recorded by a multichannel digital recording system developed using commercial off-the-shelf (COTS) equipments. A perceptual analysis/measurement system …


Cost Allocation For Transmission Investment Using Agent-Based Game Theory, Jakapun Mepokee, David Lee Enke, Badrul H. Chowdhury Jan 2004

Cost Allocation For Transmission Investment Using Agent-Based Game Theory, Jakapun Mepokee, David Lee Enke, Badrul H. Chowdhury

Engineering Management and Systems Engineering Faculty Research & Creative Works

Due to electrical power restructuring, a dramatic change has been made to the generation and transmission sectors of the power industry. Rules and legislation are continuously changing. To promote more competition, transmission has to be expanded or upgraded to remove congestion and market power. The cost allocation of new investment in transmission has to be recalculated. The socialization methods of the past have been shown to be unfair to some market and network participants. The decentralization of cost allocation must be considered. The proposed paper provides a comparison between traditional cost allocation methods and a new cost allocation method based …


Termination-Dependent Diversity Performance Of Coupled Antennas: Network Theory Analysis, Michael A. Jensen, Jon W. Wallace Jan 2004

Termination-Dependent Diversity Performance Of Coupled Antennas: Network Theory Analysis, Michael A. Jensen, Jon W. Wallace

Faculty Publications

A new analysis of mutually coupled diversity antenna systems is presented that includes the effects of coupling on the radiation pattern and received power. This analysis, based upon the network scattering parameters, makes use of the singular value decomposition to both specify the characteristics of and analyze terminated antenna networks. The approach facilitates a simplified proof of the multiport conjugate matching condition as well as development of expressions for diversity performance as a function of various impedance terminations. Application of the analysis to coupled dipole antennas characterized using full-wave electromagnetic analysis leads to a comprehensive examination of the diversity performance …


Optimal Diversity Combining Based On Noisy Channel Estimation, Jingxian Wu, Chengshan Xiao, N. C. Beaulieu Jan 2004

Optimal Diversity Combining Based On Noisy Channel Estimation, Jingxian Wu, Chengshan Xiao, N. C. Beaulieu

Electrical and Computer Engineering Faculty Research & Creative Works

The performances of coherent diversity receivers with noisy channel estimation are examined. Fading channel gain estimates are modeled as sums of the true fading channel gain values plus independent Gaussian distributed estimation errors. The optimal diversity receiver for coherent reception with noisy channel state information and independent and identically distributed fading channels is derived. Exact expressions for the average error probability of optimal diversity MPSK with noisy channel estimation are derived for Rayleigh and Ricean fading channels; closed-form expressions are obtained for some special cases. Some interesting observations regarding practical diversity receiver design for higher-order modulation formats are drawn.


Space-Time Fading Correlation Functions Of A 3-D Mimo Channel Model, Sang-Yick Leong, Y. Rosa Zheng, Chengshan Xiao Jan 2004

Space-Time Fading Correlation Functions Of A 3-D Mimo Channel Model, Sang-Yick Leong, Y. Rosa Zheng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Space-time correlation functions between the links of MIMO Rayleigh fading channels are derived using a new three-dimensional (3-D) cylinder scattering model. Closed form, mathematically tractable formulas are obtained for the space-time correlation functions for general MIMO systems where the base station and mobile station antennas may be arranged in 3-D space. It is shown that the correlation functions computed by the 3-D cylinder model are of significant difference than those of the conventional 2-D Clarke''s isotropic scattering model for vertically placed antennas. The general formulas of the correlation functions includes the 2-D Clarke''s model and the 3-D SIMO, MISO models …


Spectrum Visualization And Measurement Of Power Parameters Of Microwave Wide-Band Noise, Marina Koledintseva, Alexander A. Kitaytsev, V. A. Konkin, V. Radchenko Jan 2004

Spectrum Visualization And Measurement Of Power Parameters Of Microwave Wide-Band Noise, Marina Koledintseva, Alexander A. Kitaytsev, V. A. Konkin, V. Radchenko

Electrical and Computer Engineering Faculty Research & Creative Works

A method for an adequate visualization of a microwave intense noise spectrum envelope in a wide frequency range (several octaves), measurement of its power parameters, and detection of a narrow-band signal with unknown frequency and power against the noise background is presented. This method is based on an application of a nonheterodyne principle of microwave frequency (and power) conversion using a gyromagnetic converter, which operates in two regimes in turn: the resonance detection and the cross-multiplication. A block scheme and an operation of a two-channel measuring device combining the mentioned functions are discussed.


Ergodic Capacity Of Doubly Selective Rayleigh Fading Mimo Channels, Chengshan Xiao, Y. Rosa Zheng Jan 2004

Ergodic Capacity Of Doubly Selective Rayleigh Fading Mimo Channels, Chengshan Xiao, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

The ergodic capacity is investigated for doubly selective (frequency selective and time varying) MIMO Rayleigh fading channels. A closed form formula is derived that quantifies the effect of the ISI fading on the ergodic capacity into an ISI degradation factor. It is discovered that, in general frequency selective MIMO channels, the inter-tap correlations of the ISI fading will reduce the ergodic capacity comparing to the frequency flat fading channel. Only in the special case when the ISI fading does not have inter-tap correlations will the ergodic capacity be the same as that of the frequency flat channel. This new formula …


Unmanned Vehicle Navigation Using Swarm Intelligence, Sheetal Doctor, Ganesh K. Venayagamoorthy Jan 2004

Unmanned Vehicle Navigation Using Swarm Intelligence, Sheetal Doctor, Ganesh K. Venayagamoorthy

Electrical and Computer Engineering Faculty Research & Creative Works

Unmanned vehicles are used to explore physical areas where humans are unable to go due to different constraints. There have been various algorithms that have been used to perform this task. This paper explores swarm intelligence for searching a given problem space for a particular target(s). The work in this paper has two parts. In the first part, a set of randomized unmanned vehicles are deployed to locate a single target. In the second part, the randomized unmanned vehicles are deployed to locate various targets and are then converged at one of targets of a particular interest. Each of the …


Decentralized Neural Network Control Of A Class Of Large-Scale Systems With Unknown Interconnection, Wenxin Liu, Jagannathan Sarangapani, Donald C. Wunsch, Mariesa Crow Jan 2004

Decentralized Neural Network Control Of A Class Of Large-Scale Systems With Unknown Interconnection, Wenxin Liu, Jagannathan Sarangapani, Donald C. Wunsch, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

A novel decentralized neural network (DNN) controller is proposed for a class of large-scale nonlinear systems with unknown interconnections. The objective is to design a DNN for a class of large-scale systems which do not satisfy the matching condition requirement. The NNs are used to approximate the unknown subsystem dynamics and the interconnections. The DNN is designed using the back stepping methodology with only local signals for feedback. All of the signals in the closed loop (system states and weights estimation errors) are guaranteed to be uniformly ultimately bounded and eventually converge to a compact set.


Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng Jan 2004

Ergodic Capacity Of Mimo Triply Selective Rayleigh Fading Channels, Chengshan Xiao, Y. Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

New results are presented for the ergodic capacity of spatially-correlated, time-varying and frequency-selective (i.e., triply selective) MIMO Rayleigh fading channels. Simplified capacity formulas are also derived for special cases such as SIMO and MISO triply selective fading channels. A closed form formula is proposed that quantifies the effect of the frequency-selective fading on the ergodic capacity into an intersymbol interference (ISI) degradation factor. It is discovered that, in general frequency-selective MIMO channels, the ISI inter-tap correlations reduce the ergodic capacity compared to the frequency flat fading channel. Only in the special case when the fading does not have ISI inter-tap …


Measuring The Robustness Of A Resource Allocation, Shoukat Ali, A. A. Maciejewski, Howard Jay Siegel, Jong-Kook Kim Jan 2004

Measuring The Robustness Of A Resource Allocation, Shoukat Ali, A. A. Maciejewski, Howard Jay Siegel, Jong-Kook Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Parallel and distributed systems may operate in an environment that undergoes unpredictable changes causing certain system performance features to degrade. Such systems need robustness to guarantee limited degradation despite fluctuations in the behavior of its component parts or environment. This research investigates the robustness of an allocation of resources to tasks in parallel and distributed systems. The main contributions are 1) a mathematical description of a metric for the robustness of a resource allocation with respect to desired system performance features against multiple perturbations in multiple system and environmental conditions, and 2) a procedure for deriving a robustness metric for …