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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

Analysis and design of simple antenna geometries for broadband high frequency communications.

Fourie, Andries Petrus Cronje. January 1991 (has links)
A thesis submitted to the Faculty of Engineering. University of the Witwatersrand. Johannesburg in fulfilment of the requirements for the degree of Doctor of Philosophy. / The general argument of the thesis is that the design of broadband antennas demands a thorough understanding of the factors influencing the current distribution on antenna wires. Specifically. current distribution concepts are used to improve the evaluation and design of small broadband antennas for the high frequency (HF) 2 to 30 MHz range. The current distribution on an antenna governs its input impedance, radiation efficiency and radiation patterns. (Abbreviation abstract) / Andrew Chakane 2018
2

New techniques of injection locking in communication systems.

January 1993 (has links)
by Wong, Kwok-wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 90-93). / DEDICATION / ACKNOWLEDGEMENTS / ABSTRACT / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter CHAPTER 2 --- BASIC OSCILLATOR DESIGN --- p.5 / Chapter CHAPTER 3 --- FUNDAMENTAL INJECTION LOCKING --- p.12 / Chapter 3.1 --- INTRODUCTION --- p.12 / Chapter 3.2 --- NONLINEAR OSCILLATOR MODELS --- p.13 / Chapter 3.3 --- TYPES OF INJECTION LOCKED OSCILLATOR --- p.24 / Chapter 3.4 --- INJECTION LOCKING CHARACTERISTICS --- p.26 / Chapter 3.5 --- CONCLUSION --- p.31 / Chapter CHAPTER 4 --- SUBHARMONIC INJECTION LOCKING --- p.32 / Chapter 4.1 --- INTRODUCTION --- p.32 / Chapter 4.2 --- SUBHARMONIC INJECTION LOCKING --- p.32 / Chapter 4.3 --- SUBHARMONIC INJECTION LOCKING CHARACTERISTICS --- p.36 / Chapter 4.4 --- CONCLUSION --- p.40 / Chapter CHAPTER 5 --- EXPERIMENTAL INVESTIGATIONS ON INJECTION LOCKING --- p.41 / Chapter 5.1 --- INTRODUCTION --- p.41 / Chapter 5.2 --- EXPERIMENTAL CHARACTERISTICS --- p.43 / Chapter 5.3 --- NON-INTEGRAL SUBHARMONIC LOCKING --- p.53 / Chapter 5.3.1 --- Nonlinear feedback model --- p.53 / Chapter 5.3.2 --- Circuit description --- p.55 / Chapter 5.3.3 --- Experimental results --- p.59 / Chapter 5.3.4 --- Summary --- p.64 / Chapter 5.4 --- SELECTIVE SUBHARMONIC LOCKING RANGE ENHANCEMENT --- p.65 / Chapter 5.4.1 --- Mulit-feedback nonlinear model --- p.65 / Chapter 5.4.2 --- Circuit description --- p.65 / Chapter 5.4.3 --- Experimental results --- p.69 / Chapter 5.4.4 --- Summary --- p.71 / Chapter 5.5 --- FEEDBACK TYPE INJECTION LOCKED OSCILLATOR --- p.72 / Chapter 5.5.1 --- Feedback type injection locked oscillator model with different injection points --- p.72 / Chapter 5.5.2 --- Circuit description --- p.73 / Chapter 5.5.3 --- Experimental results --- p.76 / Chapter 5.5.4 --- Summary --- p.76 / Chapter 5.6 --- PHASE TUNING BEYOUND 180 DEGREES BY INJECTION LOCKING --- p.79 / Chapter 5.6.1 --- Phase change by single injection locking --- p.79 / Chapter 5.6.2 --- Phase change by cascaded injection locking --- p.80 / Chapter 5.6.3 --- Experimental results --- p.85 / Chapter 5.6.4 --- Summary --- p.88 / Chapter 5.7 --- CONCLUSION --- p.88 / Chapter CHAPTER 6 --- CONCLUSION --- p.89 / REFERENCES --- p.90 / LIST OF ACCEPTED AND SUBMITTED / PUBLICATIONS DURING THE PERIOD OF STUDY
3

Multilevel diversity coding with independent data streams.

January 1995 (has links)
by Hau Ka Pun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 102-[103]). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- A General Review of MDCS --- p.1 / Chapter 1.2 --- MDCS with Independent Data Streams --- p.4 / Chapter 1.3 --- Admissible Coding Rate Region --- p.5 / Chapter 1.4 --- Distribution of Information in Different Encoders --- p.6 / Chapter 1.5 --- Multilevel Diversity Coding by Superposition --- p.8 / Chapter 1.6 --- Optimality of Superposition --- p.11 / Chapter 1.7 --- Different MDCS coding schemes --- p.17 / Chapter 2 --- MDCS's with Three Encoders --- p.20 / Chapter 2.1 --- 2-level-3-encoder MDCS --- p.21 / Chapter 2.2 --- 3-level-3-encoder MDCS --- p.31 / Chapter 3 --- Symmetrical Multilevel Diversity Coding System --- p.49 / Chapter 3.1 --- Introduction --- p.49 / Chapter 3.2 --- "SMDCS[2,m,(l,m)]" --- p.53 / Chapter 3.3 --- "SMDCS[3, m,(l,2,m)]" --- p.56 / Chapter 3.4 --- "SMDCS[3,m,(l,3,m)]" --- p.62 / Chapter 3.5 --- "SMDCS[4,4, (1,2,3,4)]" --- p.66 / Chapter 4 --- Convex Analysis of Coding Rate Region of DCS --- p.72 / Chapter 4.1 --- Introduction --- p.72 / Chapter 4.2 --- Polyhedral Sets --- p.73 / Chapter 4.3 --- Addition of Polyhedral Sets --- p.75 / Chapter 4.4 --- Algorithms to Enumerate Extreme Points and Decompose Tuples --- p.86 / Chapter 5 --- Conclusion and Further Research --- p.90 / Chapter 5.1 --- Conclusion --- p.90 / Chapter 5.2 --- Suggestions for Further Research --- p.91 / Appendix --- p.93 / Chapter A --- Proof of Equivalence of rsp and Rsp in Chapter3 --- p.93 / Chapter A.1 --- r2m1m and R2m1m --- p.93 / Chapter A.2 --- r33123 and R33123 --- p.94 / Chapter A.3 --- r441234 and. R441234 --- p.96 / Chapter B --- A Class of MDCS Where Superposition is Always Not Optimal --- p.99 / Bibliography --- p.102
4

Cellular automata for dynamic S-boxes in cryptography

Luckett, William Matthew. January 2007 (has links) (PDF)
Thesis (M.Eng.)--University of Louisville, 2007. / Title and description from thesis home page (viewed December 14, 2007). Department of Computer Engineering and Computer Science. "September 2007." Includes bibliographical references (p. 74-76).
5

Identifying hospital communication activities for a functional communication measure in the acute hospital setting /

McCooey, Robyn. January 2001 (has links) (PDF)
Thesis (M. Sp. Path. St.)--University of Queensland, 2002. / Includes bibliographical references.
6

Power optimised narrowband power-line communication systems

Sun, Yuhao January 2013 (has links)
No description available.
7

Optical technologies with embedded electronics for future cost effective ultra-fast communication systems

Lee, Sim Heung January 2013 (has links)
No description available.
8

Capacitated network design with column generation

Gong, Panjing 05 1900 (has links)
No description available.
9

Real-time estimation of amplitude and group delay distortion in a PSK line-of-sight communications channel

Prescott, Glenn Eugene 08 1900 (has links)
No description available.
10

Optical add-drop multiplexers and amplifier placement methods for metropolitan WDM ring network

Tran, An Vu Unknown Date (has links) (PDF)
The tremendous growth in broadband communication services, brought about by the phenomenal expansion of the Internet, has triggered an unprecedented demand for bandwidth in telecommunication networks. Optical fibre communication technology has kept up with the growing bandwidth demand by exploiting wavelength division multiplexing (WDM) technology. WDM is now beginning to expand from a network core technology towards the metropolitan and access networks with the goal of bringing the benefit of cost and network efficiencies of the optical networking revolution to the end users. The advent of metropolitan WDM networks has motivated the work in this thesis to develop new devices and design methods in order to reduce cost and improve network performance. (For complete abstract open document)

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