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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Eigenstructure analysis of automobile steering dynamics with application to robust four wheel steering control

Chu, Tzyy-Wen January 2001 (has links)
No description available.
2

Study of Multiport Antenna Systems on Terminals for WLAN : MIMO Technology

El Rashid, Mohamad January 2009 (has links)
<p>Using more than just on antenna can significantly speed up the data rate in a wireless communication system. These systems are commonly referred to as Diversity- and MIMO-systems. Due to tight volume restriction for the antennas, e.g. in a mobile phone, electromagnetic coupling between the antennas will degrade the capacity of the wireless system and lower the coverage.</p><p><p>In the proposed thesis, a thorough study of Ethertronics’ standard antennas will be established in which the antennas will be used in a multiport system, e.g. MIMO. The thesis will be strongly related to Ethertronics’ engagement in Chase and therefore also dependent on the latest progresses on MPA (Multiport Analyzer) developed in Chase. The thesis will result in a working methodology how to use MPA plus design-, location- and orientation rules for the standard antennas used in a multiport system.</p></p>
3

Study of Multiport Antenna Systems on Terminals for WLAN : MIMO Technology

El Rashid, Mohamad January 2009 (has links)
Using more than just on antenna can significantly speed up the data rate in a wireless communication system. These systems are commonly referred to as Diversity- and MIMO-systems. Due to tight volume restriction for the antennas, e.g. in a mobile phone, electromagnetic coupling between the antennas will degrade the capacity of the wireless system and lower the coverage. In the proposed thesis, a thorough study of Ethertronics’ standard antennas will be established in which the antennas will be used in a multiport system, e.g. MIMO. The thesis will be strongly related to Ethertronics’ engagement in Chase and therefore also dependent on the latest progresses on MPA (Multiport Analyzer) developed in Chase. The thesis will result in a working methodology how to use MPA plus design-, location- and orientation rules for the standard antennas used in a multiport system.
4

Study of MIMO, orthogonal codes and core operator architecture design for ML decoder

Sevelimedu Veeravalli, Vinodh January 2007 (has links)
<p>In the high-end research process of wireless systems and in the race for the development of the new technologies, MIMO (Multiple Input, Multiple Output) is getting more attention now days. It has a high potential usage in the 3G and 4G communications and beyond. The MIMO based system has got the ability to increase the data throughput in spectrum-limited conditions. With the increase and complexity of wireless applications, the spectrum efficiency improvement in the physical layer will be saturated. MIMO is predicted to be one of the major features for the next generation wireless networking. This thesis work is a part of an ongoing project of the Generic MIMO decoder design carried out at the research laboratory, LESTER at Lorient, France. I was involved in the study of MIMO concepts, orthogonal and Space-time codes and later involved in the design and optimization of the architecture for the core operator for the ML decoder used in the reception of the MIMO system,which is presented in this report work.</p>
5

Interference Alignment with Distributed Antenna Systems

Starr, Jonathan Kenneth 17 February 2012 (has links)
This paper considers the combination of interference alignment and distributed antenna systems to improve the rate performance of cell-edge users in the cellular downlink. Because the power resources of each antenna in distributed antenna systems are geographically separated, practical implementations of distributed antenna systems require consideration of per-antenna power constraints on the transmit antennas. For this reason, we consider interference alignment with two types of power constraints: per-antenna power inequality constraints and per-antenna power equality constraints. On one hand, we show that interference alignment with per-antenna power inequality constraints is arbitrarily feasible using a technique of antenna power back-off but suffers from a loss of performance that we quantify in the case of Rayleigh-fading. On the other hand, we show that interference alignment with per-antenna power equality constraints does not suffer from a systematic loss of performance but yet requires more antennas to be feasible. We develop algorithms for implementing interference alignment with both types of constraints and numerically validate the results of our analysis. Finally, we demonstrate using the 3rd Generation Partnership Project spatial channel model in a cellular setting that interference alignment with distributed antenna systems has better rate performance than interference alignment with centralized antenna systems throughout the entire cell, especially near the cell boundary. / text
6

Study of MIMO, orthogonal codes and core operator architecture design for ML decoder

Sevelimedu Veeravalli, Vinodh January 2007 (has links)
In the high-end research process of wireless systems and in the race for the development of the new technologies, MIMO (Multiple Input, Multiple Output) is getting more attention now days. It has a high potential usage in the 3G and 4G communications and beyond. The MIMO based system has got the ability to increase the data throughput in spectrum-limited conditions. With the increase and complexity of wireless applications, the spectrum efficiency improvement in the physical layer will be saturated. MIMO is predicted to be one of the major features for the next generation wireless networking. This thesis work is a part of an ongoing project of the Generic MIMO decoder design carried out at the research laboratory, LESTER at Lorient, France. I was involved in the study of MIMO concepts, orthogonal and Space-time codes and later involved in the design and optimization of the architecture for the core operator for the ML decoder used in the reception of the MIMO system,which is presented in this report work.
7

Precoder Design for Cooperative Cognitive Radio Systems

Budhathoki, Krishna Ram 21 May 2013 (has links)
No description available.
8

Nussbaum gain based iterative learning control for a class of multi-input multi-output nonlinear systems.

Jiang, Ping, Chen, H. January 2005 (has links)
Yes / An adaptive iterative learning control(ILC) approach is proposed for a class of multi-input multi-output (MIMO) uncertain nonlinear systems without prior knowledge about system control gain matrices. The Nussbaum-type gain and the positive definite discrete matrix kernel are proposed for dealing with selection of the unknown control gain and learning of the repeatable uncertainties, respectively. Asymptotic convergence for a trajectory tracking within a finite time interval is achieved through repetitive tracking. Simulations are carried out to show the validity of the proposed control method.
9

Output Feedback Stabilization for MIMO Semi-linear Stochastic Systems with Transient Optimisation

Zhang, Qichun, Hu, L., Gow, J. 03 October 2019 (has links)
Yes / This paper investigates the stabilisation problem and consider transient optimisation for a class of the multi-input-multi-output (MIMO) semi-linear stochastic systems. A control algorithm is presented via an m-block backstepping controller design where the closed-loop system has been stabilized in a probabilistic sense and the transient performance is optimisable by optimised by searching the design parameters under the given criterion. In particular, the transient randomness and the probabilistic decoupling will be investigated as case studies. Note that the presented control algorithm can be potentially extended as a framework based on the various performance criteria. To evaluate the effectiveness of this proposed control framework, a numerical example is given with simulation results. In summary, the key contributions of this paper are stated as follows: 1) one block backstepping-based output feedback control design is developed to stabilize the dynamic MIMO semi-linear stochastic systems using a linear estimator; 2) the randomness and probabilistic couplings of the system outputs have been minimized based on the optimisation of the design parameters of the controller; 3) a control framework with transient performance enhancement of multi-variable semi-linear stochastic systems has been discussed. / Higher Education Innovation Fund (No. HEIF 2018-2020), De Montfort University, Leicester, UK.
10

<b>SCALABLE MULTI INPUT MULTI OUTPUT DC BUCK CONVERTER USING MULTISTAGE AND MULTIPHASE TECHNIQUES</b>

Khalifa Ahmed Alremeithi (14661221) 18 July 2024 (has links)
<p dir="ltr">The demand for renewable energy and electric vehicles (EVs) is increasing, necessitating efficient energy conversion and management solutions. The thesis addresses the critical challenge of dynamically converting multiple Direct Current (DC) inputs to multiple DC outputs while maintaining efficiency and scalability. The primary objective is to design and test a Multi Input Multi Output (MIMO) DC converter, focusing on verifying its scalability and load efficiency. The research investigates hardware requirements, the implementation of multiphase circuits, and the balancing of power between various inputs through multistage cycling. The study hypothesizes that multistage cycling balances the output power between inputs, and multiphase configurations can scale the converter without affecting efficiency. Methods include examining existing converters, simulating multistage circuits, and fabricating a prototype. Key deliverables include a working prototype demonstrating scalability and efficiency. Results indicate that the MIMO DC converter performs efficiently with multiple inputs and outputs, achieving over 90% efficiency. The use of Gallium Nitride (GaN) transistors and synchronous buck converter topology proves effective in minimizing losses and enhancing stability. The research holds significant value in advancing renewable energy and DC converter technology, promoting sustainability and efficient energy management. Future work should explore advanced filtration circuits, higher voltage testing, and more complex configurations to further enhance the converter's capabilities.</p>

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