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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.
21

Cooperative routing in wireless ad hoc networks.

January 2007 (has links)
Cheung, Man Hon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 89-94). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Rayleigh Fading Channels --- p.1 / Chapter 1.2 --- Ultra-Wideband (UWB) Communications --- p.2 / Chapter 1.2.1 --- Definition --- p.2 / Chapter 1.2.2 --- Characteristics --- p.3 / Chapter 1.2.3 --- UWB Signals --- p.4 / Chapter 1.2.4 --- Applications --- p.5 / Chapter 1.3 --- Cooperative Communications --- p.7 / Chapter 1.4 --- Outline of Thesis --- p.7 / Chapter 2 --- Background Study --- p.9 / Chapter 2.1 --- Interference-Aware Routing --- p.9 / Chapter 2.2 --- Routing in UWB Wireless Networks --- p.11 / Chapter 2.3 --- Cooperative Communications and Routing --- p.12 / Chapter 3 --- Cooperative Routing in Rayleigh Fading Channel --- p.15 / Chapter 3.1 --- System Model --- p.16 / Chapter 3.1.1 --- Transmitted Signal --- p.16 / Chapter 3.1.2 --- Received Signal and Maximal-Ratio Combining (MRC) --- p.16 / Chapter 3.1.3 --- Probability of Outage --- p.18 / Chapter 3.2 --- Cooperation Criteria and Power Distribution --- p.21 / Chapter 3.2.1 --- Optimal Power Distribution Ratio --- p.21 / Chapter 3.2.2 --- Near-Optimal Power Distribution Ratio β´ة --- p.21 / Chapter 3.2.3 --- Cooperation or Not? --- p.23 / Chapter 3.3 --- Performance Analysis and Evaluation --- p.26 / Chapter 3.3.1 --- 1D Poisson Random Network --- p.26 / Chapter 3.3.2 --- 2D Grid Network --- p.28 / Chapter 3.4 --- Cooperative Routing Algorithm --- p.32 / Chapter 3.4.1 --- Cooperative Routing Algorithm --- p.33 / Chapter 3.4.2 --- 2D Random Network --- p.35 / Chapter 4 --- UWB System Model and BER Expression --- p.37 / Chapter 4.1 --- Transmit Signal --- p.37 / Chapter 4.2 --- Channel Model --- p.39 / Chapter 4.3 --- Received Signal --- p.39 / Chapter 4.4 --- Rake Receiver with Maximal-Ratio Combining (MRC) --- p.41 / Chapter 4.5 --- BER in the presence of AWGN & MUI --- p.46 / Chapter 4.6 --- Rake Receivers --- p.47 / Chapter 4.7 --- Comparison of Simple Routing Algorithms in ID Network --- p.49 / Chapter 5 --- Interference-Aware Routing in UWB Wireless Networks --- p.57 / Chapter 5.1 --- Problem Formulation --- p.57 / Chapter 5.2 --- Optimal Interference-Aware Routing --- p.58 / Chapter 5.2.1 --- Link Cost --- p.58 / Chapter 5.2.2 --- Per-Hop BER Requirement and Scaling Effect --- p.59 / Chapter 5.2.3 --- Optimal Interference-Aware Routing --- p.61 / Chapter 5.3 --- Performance Evaluation --- p.64 / Chapter 6 --- Cooperative Routing in UWB Wireless Networks --- p.69 / Chapter 6.1 --- Two-Node Cooperative Communication --- p.69 / Chapter 6.1.1 --- Received Signal for Non-Cooperative Communication --- p.69 / Chapter 6.1.2 --- Received Signal for Two-Node Cooperative Communication --- p.70 / Chapter 6.1.3 --- Probability of Error --- p.71 / Chapter 6.2 --- Problem Formulation --- p.75 / Chapter 6.3 --- Cooperative Routing Algorithm --- p.77 / Chapter 6.4 --- Performance Evaluation --- p.80 / Chapter 7 --- Conclusion and Future Work --- p.85 / Chapter 7.1 --- Conclusion --- p.85 / Chapter 7.2 --- Future Work --- p.86 / Chapter 7.2.1 --- Distributed Algorithm --- p.87 / Chapter 7.2.2 --- Performance Analysis in Random Networks --- p.87 / Chapter 7.2.3 --- Cross-Layer Optimization --- p.87 / Chapter 7.2.4 --- Game Theory --- p.87 / Chapter 7.2.5 --- Other Variations in Cooperative Schemes --- p.88 / Bibliography --- p.89
22

Media access control for MIMO ad hoc network.

January 2007 (has links)
Ke, Bingwen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (p. 52-54). / Abstracts in Chinese and English. / Abstract --- p.3 / Acknowledgement --- p.5 / Content --- p.6 / Table of Figures --- p.8 / Chapter Chapter 1 --- Introduction --- p.9 / Chapter 1.1 --- Motivations and Contributions --- p.9 / Chapter 1.2 --- Organization of the Thesis --- p.11 / Chapter Chapter 2 --- Background --- p.12 / Chapter 2.1 --- Multiple-Input-Multiple-Output (MIMO) System --- p.12 / Chapter 2.1.1 --- Basic MIMO Structure --- p.12 / Chapter 2.1.2 --- Multiple User Detection (MUD) in MIMO Networks --- p.14 / Chapter 2.2 --- IEEE 802.11 --- p.16 / Chapter 2.2.1 --- CSMA/CA in 802.11 --- p.16 / Chapter 2.2.2 --- CSMA/CA(k) in 802.1 In --- p.18 / Chapter 2.2.3 --- Co-channel Transmission in MIMO WLAN --- p.19 / Chapter Chapter 3 --- Channel Correlation in MIMO Ad Hoc Networks --- p.20 / Chapter 3.1 --- Introduction of Channel Correlation --- p.20 / Chapter 3.2 --- Channel Correlation Threshold --- p.25 / Chapter Chapter 4 --- MAC with SINR Threshold --- p.28 / Chapter Chapter 5 --- Performance Evaluation of MWST in Fully-Connected Networks --- p.33 / Chapter Chapter 6 --- MAC with SINR Threshold (MWST) in Partially-Connected Networks --- p.38 / Chapter 6.1 --- Hidden Link Problem in Partially-Connected Networks --- p.38 / Chapter Chapter 7 --- Performance Evaluation in Partially-Connected Networks --- p.42 / Chapter 7.1 --- Fairness Issues in CSMA/CA(k) --- p.42 / Chapter 7.2 --- Fairness Performance of MWST --- p.45 / Conclusion --- p.50 / References --- p.52
23

On timeslots scheduling algorithms of wireless ad hoc network.

January 2008 (has links)
Chau, Wai Shing. / Thesis submitted in: October 2007. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 64-66). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.ii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Ad hoc network --- p.1 / Chapter 1.2 --- Outline of the thesis --- p.3 / Chapter 2 --- Background Study --- p.4 / Chapter 2.1 --- Multiple Access Control (MAC) --- p.4 / Chapter 2.1.1 --- Time Division Multiple Access (TDMA) --- p.5 / Chapter 2.1.2 --- Spatial TDMA (STDMA) --- p.5 / Chapter 2.2 --- Interference Models --- p.6 / Chapter 2.2.1 --- Primary and Secondary Interferences --- p.6 / Chapter 2.2.2 --- Interference-based Model --- p.7 / Chapter 2.2.3 --- Graph-based Model --- p.7 / Chapter 2.3 --- Scheduling in Graph-based Model --- p.8 / Chapter 2.3.1 --- Conflict Graph --- p.9 / Chapter 3 --- Scheduling Algorithms in Ring Networks --- p.11 / Chapter 3.1 --- Problem Formulation --- p.12 / Chapter 3.2 --- Regular Sequences --- p.14 / Chapter 3.3 --- Scheduling in Ring Networks with Even-number of Edges --- p.22 / Chapter 3.4 --- Scheduling in Ring Networks with an Odd-number of Edges --- p.26 / Chapter 3.4.1 --- Scheduling by Reducing a Ring Network with an Odd-number of Edges into a Ring- Network with an Even-number of Edges --- p.28 / Chapter 3.4.2 --- Scheduling by Shifting the Regular Sequences --- p.32 / Chapter 3.5 --- Discussion --- p.42 / Chapter 3.6 --- Conclusion --- p.42 / Chapter 4 --- Distributed Scheduling Algorithm for Ad Hoc Network --- p.43 / Chapter 4.1 --- Problem Formulation --- p.44 / Chapter 4.2 --- Distributed Scheduling Heuristic Algorithm --- p.44 / Chapter 4.2.1 --- Weight functions --- p.44 / Chapter 4.2.2 --- Main Algorithm --- p.46 / Chapter 4.3 --- Centralized algorithm on a chain network --- p.49 / Chapter 4.4 --- Performance of the Algorithm on Chain Network --- p.50 / Chapter 4.4.1 --- Comparison 1 --- p.51 / Chapter 4.4.2 --- Comparsion 2 --- p.52 / Chapter 4.4.3 --- Comparsion 3 --- p.53 / Chapter 4.5 --- Performance of the Algorithm on Random Conflict graph --- p.55 / Chapter 4.6 --- Discussion --- p.57 / Chapter 4.7 --- Special Graphs --- p.58 / Chapter 4.8 --- Conclusion --- p.61 / Chapter 5 --- Conclusion --- p.62 / Bibliography --- p.64
24

Interference-aware TDMA link scheduling and routing in wireless ad hoc networks.

January 2007 (has links)
Shen, Yuxiu. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 61-64). / Abstracts in Chinese and English. / 摘要........Error! Bookmark not defined / Abstract --- p.iii / Acknowledgement --- p.v / Content --- p.viii / List of Figures --- p.xi / List of Tables --- p.xii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background Overview --- p.1 / Chapter 1.2 --- Motivation and Related Work --- p.2 / Chapter 1.3 --- Our Contribution --- p.3 / Chapter 1.4 --- Organization of the Thesis --- p.5 / Chapter Chapter 2 --- Preliminaries --- p.6 / Chapter 2.1 --- TDMA Technology --- p.6 / Chapter 2.1.1 --- Features of TDMA --- p.8 / Chapter 2.2 --- Previous Study on TDMA Link Scheduling --- p.8 / Chapter 2.3 --- Typical Network and Interference Models --- p.10 / Chapter Chapter 3 --- System Model --- p.14 / Chapter 3.1 --- Physical Layer Interference Model --- p.14 / Chapter 3.2 --- Objective of the Problem --- p.15 / Chapter 3.3 --- Rate Matrices for Transmission Sets --- p.17 / Chapter 3.4 --- Airtime Allocation --- p.19 / Chapter Chapter 4 --- Problem Formulation and Its Solution --- p.20 / Chapter 4.1 --- LP Formulation of Optimal TDMA Link Scheduling --- p.21 / Chapter 4.2 --- Solution to the Optimal Air Time Allocation Problem --- p.22 / Chapter 4.3 --- n-length Chain Network --- p.24 / Chapter 4.3.1 --- Adaptive Rate Transmission --- p.25 / Chapter 4.3.2 --- Fixed Rate Transmission --- p.27 / Chapter Chapter 5 --- Bad Transmission Set Removal Algorithm (BTSR) --- p.30 / Chapter 5.1 --- A 7-node Chain Example --- p.30 / Chapter 5.2 --- BTSR Algorithm --- p.32 / Chapter Chapter 6 --- Randomized Decentralized Scheduling Algorithm (RDSA) --- p.35 / Chapter 6.1 --- RDSA Algorithm --- p.35 / Chapter 6.2 --- Pseudo Code of RDSA --- p.37 / Chapter 6.3 --- The Flow Chart of RDSA --- p.39 / Chapter Chapter 7 --- Performance Evaluation --- p.41 / Chapter 7.1 --- Performance of Cross-layer TDMA Link Scheduling --- p.41 / Chapter 7.2 --- Complexity Analysis and Comparisons for BTSR+LP and LP --- p.46 / Chapter 7.2.1 --- Complexity of LP Problem --- p.47 / Chapter 7.2.2 --- Problem Size Reduced by BTSR --- p.48 / Chapter 7.2.3 --- Revised BTSR Algorithm --- p.49 / Chapter 7.2.4 --- The Complexity Issues --- p.51 / Chapter 7.3 --- Performance and Complexity Issues for RDSA --- p.52 / Chapter Chapter 8 --- Conclusion and Future Work --- p.57 / Chapter 8.1 --- Conclusions --- p.57 / Chapter 8.2 --- Future Work --- p.58 / Bibliography
25

Improving geographic routing with neighbor sectoring

Jin, Jingren. Lim, Alvin S. January 2007 (has links)
Thesis--Auburn University, 2007. / Abstract. Includes bibliographic references (p.44-46).
26

Connectionless approach--a localized scheme to mobile ad hoc networks

Ho, Yao Hua. January 2009 (has links)
Thesis (Ph.D.)--University of Central Florida, 2009. / Adviser: Kien A. Hua. Includes bibliographical references (p. 131-138).
27

Energy-efficient connected K-coverage, duty-cycling, and geographic forwarding In wireless sensor networks

Ammari, Habib M. January 2008 (has links)
Thesis (Ph.D.) -- University of Texas at Arlington, 2008.
28

An empirical study of ad-hoc sensor network for localization on the practical issues /

Shen, Zhong. January 2009 (has links)
Includes bibliographical references (p. 45-47).
29

Secure and privacy-preserving protocols for VANETs

Chim, Tat-wing., 詹達榮. January 2011 (has links)
published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy
30

Distributed algorithmic studies in wireless ad hoc networks

Yu, Dongxiao, 于东晓 January 2014 (has links)
It has been envisioned that in the near future, wireless ad hoc networks would populate various application fields, ranging from disaster relief, environmental monitoring, surveillance, to medical applications, the observation of chemical and biological processes and community mesh networks. The decentralized and self-organizing nature of wireless ad hoc networks makes distributed algorithms fit very well in these networks, which however pose great challenges to the algorithm designers as they try to achieve optimal efficiency in communications. In this thesis, I develop a set of distributed algorithms addressing these challenges and solving some fundamental communication problems in wireless ad hoc networks. Communications in wireless ad hoc networks happen on a shared medium, and consequently are subject to interference. The first part of the thesis focuses on disseminating information on multiple-access channels while avoiding collisions. For both single-channel and multi-channel networks, the complexity of information dissemination is investigated, and nearly optimal distributed algorithms are proposed. The second part of the thesis focuses on designing efficient distributed algorithms for some fundamental problems under the physical Signal-to-Interference-plus-Noise-Ratio (SINR) interference model. The SINR model defines global fading interference with which the success of a signal reception depends on all simultaneous transmissions. Compared with graph based models, the SINR model reflects the fading and cumulative nature of radio signals. Hence, the SINR model represents the physical reality more precisely. However, the global nature of the SINR model makes the analysis of distributed algorithms much more challenging. Two types of fundamental problems are addressed in this part. The first type is closely related to communication coordination, including the wireless link scheduling problem and the node coloring problem. The second type of problems are about basic communication primitives, including the local broadcasting problem and the multiple-message broadcast problem. I investigate the complexity of these fundamental problems under the SINR interference model, and present efficient or optimal distributed algorithms. In the third part of the thesis, I propose a general interference model that can include commonly adopted interference models as special cases, and study whether efficient distributed algorithms can still be designed and analyzed in such a general model. Specifically, the affectance model is proposed in this part, which depicts the relative interference (affectance) on communication links caused by transmitting nodes. Both graph based models and the SINR model can be transformed into the affectance model. Under this general model, distributed algorithms with worst-case guarantees for the local broadcasting problem are presented. I also show how to make use of the developed techniques to get nearly optimal algorithms under the graph based model and the SINR model. / published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy

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