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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

Characterizing the Transient and Stationary Response of the TAU 2 Camera

Wilhite, Jeffrey Ryan January 2016 (has links)
The purpose of this research is to learn how a FLIR Tau 2 infrared camera reacts to stimuli to, later on, preform a calibration of the camera. This included measuring the line spread function (LSF), quantifying the thermal blooming, looking at the response to thermal changes in the focal plane array (FPA), and measuring the response of different temperature and speed sub-pixel objects streaking across the FPA to backtrack what the actual size, speed, shape and temperature of unknown objects were. This work will provide information to help in performing a calibration on the camera necessary to be able to get performance similar to that of a cooled sensor out of an uncooled sensor. There was not enough time to fully understand the reaction of the camera to different stimuli, which would require much more effort, but there was a large amount of information gathered that can greatly increase the understanding of the camera and help in performing calibration of the camera later on.
22

Study of Optical Destruction Techniques for Optical Discs

Choi, Taeyoung January 2008 (has links)
The topic of this dissertation is on the investigation of optical techniques for completely destroying data stored in optical discs. Complete and secure destruction of data is important when disposal of an optical disc containing sensitive and possibly classified information is concerned, since some information can be retrieved even from a fragment of a disc. After several candidate techniques and related systems are examined and fundamental system components are identified, an optical data destruction (ODD) system using a focused high power laser beam is devised, and a prototype system is designed and constructed. The ODD system uses a high power laser diode (HPLD) to expose data marks on optical discs and maintains the focused laser beam on a data layer by a focus servo using a diffractive optical element (DOE).The optical characteristics of the beam emitted from an HPLD are thoroughly investigated, and a few methods of modeling an HPLD beam in an optical system are studied. With the understanding of the HPLD beam properties, a limited-divergence raytracing (LDRT) model is developed to predict the propagation behavior of the HPLD beam in an optical system and shows good agreement with the real HPLD beam. This LDRT method is used to model the HPLD beam in the ODD system and simulate the resultant focus error signal with and without fabrication errors.The DOE focus sensor overcomes the problems in conventional focus sensors associated with the use of an intense line beam. The DOE comprising two angled gratings is designed to use only two weak 3rd order beams for focus sensing and fabricated on a chrome-coated glass substrate using a maskless lithography tool.The constructed ODD system is then used to perform destruction tests on various optical discs, which are examined using static and dynamic methods of data observation and retrieval. The observations show that data marks are optical invisible or completely covered with numerous micro-bubbles. These test results demonstrate that secure and complete destruction of data on optical discs is achieved using an ODD system. Successful destruction, however, depends greatly on exposure conditions and the type of optical media.
23

Modeling Scatter in Composite Media

Fest, Eric January 2008 (has links)
A theoretical model of optical scattering in materials consisting of densely packed spherical particles is developed that can be used to predict its optical properties given its physical characteristics. The inputs to this model are the waveband of interest, the complex refractive indicies and particle size distribution of the materials that comprise the media (including any contaminants), the density and sizes of any pores in the media, and the dimensions of the media slab. The outputs of this model are the specular transmittance and emissivity vs. wavelength of the media, and it's Bidirectional Scattering Distribution Function (BSDF) versus scatter angle, wavelength, and incident polarization. The results of this model are compared to measured transmittance and BSDF data.
24

Time Domain Spectroscopy of Graphene

Roberts, Adam January 2012 (has links)
This dissertation describes the response of graphene and graphene fragments to ultrafast optical pulses. I will first describe how we created few-cycle optical pulses for interacting with the graphene lattice. These pulses are created through filamentation based pulse compression. I studied how the filamentation process can be optimized through simple means to create the shortest possible pulse. I then examine the extent to which graphene can withstand irradiation from intense ultra-fast pulses. I examine both the high intensity regime at which a single laser pulse will ablate the graphene and a more moderate regime that slowly degrades the graphene from long term exposure to ultrafast pulses. The knowledge lets us both identify a safe working regime for driving the graphene lattice with optical fields as well as use ultrafast lasers to create graphene nano-fragments down to 2nm. Next, I explore the ultrafast dynamics of photo-excited graphene. Graphene undergoes electronic band renormalization after photo exciting carriers. By measuring a differential transmission spectrum, small changes to the band structure can be quantified. I will explain how screened exchange and electron phonon self energies provide corrections to the band structure for different times after carrier excitation. Lastly, I will describe measurements that determine the extent of electron-electron correlations in graphene fragments. By measuring the energy of the two photon state and comparing it the lowest energy one photon state in graphene fragments, we can determine the strength of the correlations in graphene systems.
25

Pixelated Mask Polarization Based Spatial Carrier Interference Microscopy

Wiersma, Joshua Thomas January 2012 (has links)
The following dissertation demonstrates the advantages of using a camera with a pixelated polarization mask allowing spatial carrier phase shifting in interference microscopy. An interference microscope in the Michelson and Linnik configurations integrates a camera equipped with a pixelated polarization mask. The camera utilizes polarization to simultaneously capture four phase shifted interferograms. Each set of four phase shifted fringe patterns permits the calculation of fringe contrast and phase at a point in the vertical scan of a test surface. The use of a short coherence source enables construction of a coarse surface profile by estimating the localization of the peak fringe contrast over the vertical scan. The coarse profile allows unwrapping of the less noisy, though circumstantially ambiguous, phase data. Established phase shifting interference microscopy methods utilize temporal phase shifting techniques. Temporal methods contrast spatial methods by acquiring each set of interferograms necessary for calculating fringe contrast and phase by scanning the test object. The scanning changes the optical path difference between the interferometer arms thus inducing the phase shifts. While both methods scan the test surface, spatial methods acquire all of the information needed to calculate fringe contrast and phase simultaneously while the temporal methods require data from multiple points in the scan. Furthermore, the focus and fringe contrast also change between phase shifts and introduce a small error in temporal methods. However, the largest source of error results from the time taken between capturing the phase shifted frames comprising each set where environmental disturbances such as vibration can change the fringe pattern. The subsequent work shows the practicality of performing interference microscopy with a pixelated polarization mask as well as the technique's relative vibration insensitivity.
26

Vegetation identification with Lidar

Helt, Michael F. 09 1900 (has links)
LIDAR data taken over the Elkhorn Slough in Central California are analyzed for terrain. The specific terrain element of interest is vegetation, and in particular, tree type. Data taken on April 12th, 2005, were taken over a 10 km x 20 km region which is mixed use agriculture and wetlands. Time return and intensity were obtained at ~2.5 m postings. Multi-spectral imagery from QuickBird was used from a 2002 imaging pass to guide analysis. Ground truth was combined with the orthorectified satellite imagery to determine regions of interest for areas with Eucalyptus, Scrub Oak, Live Oak, and Monterey Cyprus trees. LIDAR temporal returns could be used to distinguish regions with trees from cultivated and bare soil areas. Some tree types could be distinguished on the basis of the relationship between first/last extracted feature returns. The otherwise similar Eucalyptus and Monterey Cyprus could be distinguished by means of the intensity information from the imaging LIDAR. The combined intensity and temporal data allowed accurate distinction between the tree types, and task not otherwise practical with the satellite spectral imagery.
27

Synthesis, Characterization, and Optical Isomerism of Some Cobalt (III) Complex Compounds

Hu, Hung-Jen 01 1900 (has links)
This thesis investigates the synthesis, characterization, and optical isomerism of some cobalt (III) complex compounds.
28

Phase front accelerator effects in optical branching waveguides.

January 1991 (has links)
by Chan Hau Ping, Andy. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1991. / Includes bibliographies. / Acknowledgement / Abstract / Chapter 1. --- Introduction --- p.1-1 / Chapter 1.1 --- Introduction and State-of-the-Art --- p.1-1 / Chapter 1.2 --- Application of Branching Waveguides Structure --- p.1-7 / Chapter 1.2.1 --- Mach-Zehnder interferometer --- p.1-8 / Chapter 1.2.2 --- Branching waveguide switch --- p.1-11 / Chapter 1.2.3 --- TE-TM mode splitter --- p.1-16 / Chapter 1.2.4 --- Wavelength multi/demultiplexer --- p.1-18 / Chapter 1.2.5 --- Temperature sensors --- p.1-20 / Chapter 1.2.6 --- Pressure sensors --- p.1-21 / Chapter 1.2.7 --- Summary --- p.1-22 / Chapter 1.3 --- Y-Branch Waveguide --- p.1-23 / Chapter 1.3.1 --- General structure --- p.1-23 / Chapter 1.3.2 --- Characteristic of Y-branch waveguides --- p.1-25 / Chapter 1.4 --- Summary --- p.1-31 / Chapter 1.5 --- References --- p.1-32 / Chapter 2. --- Phase Front Accelerator Design (PFA) --- p.2-1 / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- PFA design in abrupt bend structure --- p.2-4 / Chapter 2.3 --- PFA design in symmetric Y-junction --- p.2-8 / Chapter 2.4 --- Advantages of using PFA design --- p.2-10 / Chapter 2.5 --- Summary --- p.2-13 / Chapter 2.6 --- References --- p.2-15 / Chapter 3. --- Beam Propagation Method (BPM) --- p.3-1 / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.1.1 --- Effective index method --- p.3-1 / Chapter 3.1.2 --- Finite element method --- p.3-2 / Chapter 3.1.3 --- Beam propagation method --- p.3-2 / Chapter 3.2 --- Theory of Beam Propagation Method --- p.3-5 / Chapter 3.2.1 --- Helmholtz beam propagation method --- p.3-5 / Chapter 3.2.2 --- Fresnel beam propagation method --- p.3-7 / Chapter 3.3 --- Simulation Consideration --- p.3-11 / Chapter 3.4 --- Conclusion --- p.3-14 / Chapter 3.5 --- References --- p.3-14 / Chapter 4. --- Operation Mechanism of Phase Front Accelerator --- p.4-1 / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- Structural Effect and Accelerator Effect --- p.4-1 / Chapter 4.3 --- Analysis and Discussion --- p.4-4 / Chapter 4.4 --- Figure of Merit in using PFA Design --- p.4-6 / Chapter 4.5 --- Conclusion --- p.4-14 / Chapter 4.6 --- References --- p.4-14 / Chapter 5. --- A 1x3 Optical Power Divider using PFA Design --- p.5-1 / Chapter 5.1 --- Introduction --- p.5-1 / Chapter 5.2 --- Design Structure --- p.5-3 / Chapter 5.3 --- Results and Discussion --- p.5-4 / Chapter 5.4 --- Conclusion --- p.5-7 / Chapter 5.5 --- References --- p.5-7 / Chapter 6. --- An Integrated Optical Beam Splitter using PFA Design --- p.6-1 / Chapter 6.1 --- Introduction --- p.6-1 / Chapter 6.2 --- Design Structure --- p.6-3 / Chapter 6.3 --- Illustrations --- p.6-7 / Chapter 6.4 --- Analysis and Discussion --- p.6-12 / Chapter 6.5 --- Conclusion --- p.6-19 / Chapter 6.6 --- References --- p.6-19 / Chapter 7. --- PFA Effects in Asymmetric Branching Waveguides --- p.7-1 / Chapter 7.1 --- Introduction --- p.7-1 / Chapter 7.2 --- Design Structure --- p.7-4 / Chapter 7.3 --- Analysis and Discussion --- p.7-4 / Chapter 7.3.1 --- PFA effects on mode conversion in Y-branch waveguide --- p.7-11 / Chapter 7.3.2 --- A 3dB coupler in asymmetric Y-branch waveguide --- p.7-16 / Chapter 7.4 --- Conclusion --- p.7-19 / Chapter 7.5 --- References --- p.7-21 / Chapter 8. --- Fabrication of Titanium In-diffused Waveguide in LiNb03 --- p.8-1 / Chapter 8.1 --- Introduction --- p.8-1 / Chapter 8.2 --- Substrate Crystal Cleaning --- p.8-2 / Chapter 8.3 --- Resist Coating --- p.8-3 / Chapter 8.4 --- Photolithography --- p.8-6 / Chapter 8.5 --- Lift-off Technique --- p.8-6 / Chapter 8.6 --- Titanium In-diffusion --- p.8-9 / Chapter 8.7 --- Lapping and Polishing --- p.8-12 / Chapter 8.8 --- Conclusion --- p.8-14 / Chapter 8.9 --- References --- p.8-14 / Chapter 9. --- Truncated Structural Y-Branch Design --- p.9-1 / Chapter 9.1 --- Introduction --- p.9-1 / Chapter 9.2 --- Theoretical Analysis --- p.9-5 / Chapter 9.3 --- Fabrication of Waveguides --- p.9-6 / Chapter 9.4 --- Experimental Set-up and Measurement --- p.9-11 / Chapter 9.5 --- Experimental Results and Discussion --- p.9-14 / Chapter 9.6 --- Conclusion --- p.9-18 / Chapter 9.7 --- References --- p.9-19 / Chapter 10. --- Conclusion --- p.10-1 / Contributions - list of publications --- p.A-l
29

On optical-signal-to-noise ratio and polarization-mode-dispersion monitoring in optical networks.

January 2004 (has links)
Man-Hong Cheung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 88-97). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Drivers for Advanced Optical Performance Monitoring (OPM) Techniques --- p.1 / Chapter 1.2 --- OPM: Definition and Significance --- p.4 / Chapter 1.3 --- The Broad Spectrum of OPM --- p.5 / Chapter 1.3.1 --- Signal Loss Monitoring --- p.7 / Chapter 1.3.2 --- Signal Alignment Monitoring --- p.7 / Chapter 1.3.3 --- Signal Quality Monitoring --- p.7 / Chapter 1.4 --- Classification of OPM Techniques --- p.9 / Chapter 1.4.1 --- Time Domain vs. Frequency Domain Monitoring --- p.9 / Chapter 1.4.2 --- Analog Parameter vs. Digital Parameter Monitoring --- p.9 / Chapter 1.4.3 --- Three-Tier OPM --- p.11 / Chapter 1.5 --- Challenges and Requirements of OPM Techniques --- p.13 / Chapter 1.6 --- Thesis Outline --- p.15 / Chapter Chapter 2 --- Review on OSNR and PMD Monitoring --- p.16 / Chapter 2.1 --- Optical Signal-to-Noise-Ratio (OSNR) Monitoring --- p.16 / Chapter 2.2 --- Out-of-band OSNR Monitoring Techniques --- p.17 / Chapter 2.2.1 --- Optical Spectral Analysis --- p.17 / Chapter 2.2.2 --- Arrayed Waveguide Grating/Tunable Filter Assisted Power Measurements --- p.19 / Chapter 2.2.3 --- RF Spectral Analysis --- p.20 / Chapter 2.2.3.1 --- Low/High RF Noise Monitoring --- p.20 / Chapter 2.2.3.2 --- Subcarrier CNR Correlation --- p.20 / Chapter 2.3 --- In-band OSNR Monitoring Techniques --- p.20 / Chapter 2.3.1 --- Polarization-Assisted OSNR Monitoring --- p.21 / Chapter 2.3.1.1 --- Polarization Extinction Method --- p.21 / Chapter 2.3.1.2 --- Polarization-Nulling --- p.22 / Chapter 2.3.1.3 --- Degree-of-Polarization (DOP) Based OSNR Monitoring --- p.23 / Chapter 2.3.2 --- In-band RF Spectral Analysis --- p.24 / Chapter 2.3.2.1 --- Orthogonal Delayed Homodyne Method --- p.24 / Chapter 2.3.2.2 --- Half Clock Frequency Constellation Monitoring / Chapter 2.3.3 --- Interferometric Approach --- p.26 / Chapter 2.3.4 --- Nonlinear Method --- p.26 / Chapter 2.4 --- Polarization-Mode-Dispersion (PMD) Monitoring --- p.27 / Chapter 2.4.1 --- Degree-of-Polarization (DOP) Monitoring --- p.29 / Chapter 2.4.2 --- RF Spectral Analysis --- p.31 / Chapter 2.4.2.1 --- PMD-Induced RF Dip Power Measurement --- p.31 / Chapter 2.4.2.2 --- Subcarriei-Based RF Power Fading Measurement --- p.32 / Chapter 2.4.3 --- "Eye-Opening, Penalty Monitoring" --- p.33 / Chapter 2.4.4 --- Phase Diversity Detection --- p.33 / Chapter 2.4.5 --- Arrival Time Measurement of Polarization-Scrambled Light --- p.34 / Chapter 2.4.6 --- Nonlinear Method --- p.34 / Chapter 2.5 --- Summary of different OSNR and PMD Monitoring Methods . --- p.34 / Chapter Chapter 3 --- On Robustness of In-band Polarization-Assisted OSNR Monitoring Techniques against PMD --- p.36 / Chapter 3.1 --- Introduction --- p.36 / Chapter 3.2 --- Impact of PMD on Polarization-Nulling --- p.37 / Chapter 3.2.1 --- Numerical Results using Ideal Rectangular Pulse --- p.40 / Chapter 3.2.2 --- Numerical and Experimental Results using Super Gaussian Pulse --- p.43 / Chapter 3.3 --- Impact of PMD on DOP-based OSNR Monitoring --- p.46 / Chapter 3.3.1 --- Numerical and Experimental Results Using Ideal Rectangular and Super-Gaussian Pulses --- p.46 / Chapter 3.4 --- Impact of PMD on Orthogonal Delayed-Homodyne Method --- p.49 / Chapter 3.5 --- Summary --- p.53 / Chapter Chapter 4 --- PMD-Insensitive OSNR Monitoring Based on Polarization-Nulling with Off-Center Narrowband Filtering --- p.54 / Chapter 4.1 --- Introduction --- p.54 / Chapter 4.2 --- Previously Proposed Schemes based on Polarization-Nulling --- p.55 / Chapter 4.2.1 --- Improved Polarization-Nulling Technique --- p.55 / Chapter 4.2.2 --- Periodic Polarization Encoding Technique --- p.57 / Chapter 4.3 --- A new PMD-Insensitive OSNR Monitoring Technique based on Polarization-Nulling with Off-Center Narrowband Filtering --- p.58 / Chapter 4.3.1 --- Principle of Proposed Technique --- p.59 / Chapter 4.3.2 --- Theoretical Calculations --- p.62 / Chapter 4.3.3 --- Experimental Results --- p.65 / Chapter 4.3.4 --- "Effects of Filter Position, Filter Bandwidth, and Filter Detuning" --- p.69 / Chapter 4.4 --- Summary --- p.71 / Chapter Chapter 5 --- Simultaneous OSNR and PMD Monitoring using Polarization Techniques --- p.72 / Chapter 5.1 --- Introduction --- p.72 / Chapter 5.2 --- Previously Proposed Scheme --- p.72 / Chapter 5.3 --- Simultaneous OSNR and PMD Monitoring by Enhanced RF Spectral Analysis --- p.74 / Chapter 5.3.1 --- Proposed Scheme --- p.75 / Chapter 5.3.2 --- Experimental Results --- p.77 / Chapter 5.4 --- DOP-based Simultaneous OSNR and PMD Monitoring --- p.80 / Chapter 5.4.1 --- Principle of Operation --- p.81 / Chapter 5.4.2 --- Experimental Results --- p.82 / Chapter 5.5 --- Summary --- p.84 / Chapter Chapter 6 --- Conclusions and Future Works --- p.85 / Chapter 6.1 --- Summary of the Thesis --- p.85 / Chapter 6.2 --- Future Works --- p.86 / Bibliography --- p.88 / Appendix - List of publications --- p.97
30

Design and applications of advanced optical modulation formats for optical metro/access transmission systems.

January 2012 (has links)
光纖通信技術與光網絡在過去三十年間極大地改變了人們的生活。雖然整個光通信行業因為2000年互聯網泡沫的破滅受到了影響,但近年來由於高清電視,移動多媒體和社交網絡的興盛,互聯網對通信網絡傳輸帶寬的需求達到了前所未有的高度,進而推動了光通信行業的再一次興盛。站在行業的高度來看,寬帶接入網無疑是推動行業發展的最主要領域。而實現寬帶接入網的最主要技術則是無源光網絡技術。無源光網絡的本質是一個樹型拓撲的光網絡,其主要的傳輸光纖可被多用戶共享,且在中央基站和用戶之間無任何有源器件,從而大大降低了網絡的成本。然而,在具體實踐中,仍然有許多的技術難題需要解決,例如:無色光網絡單元、突發性傳輸、全雙工傳輸、長距離無源光網絡和網絡功能集成等。這些技術需求亦反應了市場對通信技術發展的要求,及“更快,更便宜,更灵活“。 / 為滿足無源光網絡的技術要求,研究者們從不同的角度提出了各種解決方案,研究領域囊括光傳輸技術、新型器件、系統結構、網絡協議等等。本論文研究從傳輸碼型的角度來解決上述一項或幾項問題。研究碼型包括雙二進制反歸零碼,雙二進制曼切斯特碼,還有常規曼切斯特碼。研究內容則包括上述碼型的產生、接收、傳輸特性和系統應用等等。論文首貳章為概要和背景技術介紹,其餘幾章則按照不同的碼型分類討論。 / 本論文第一項研究課題為雙二進制反歸零碼。相比傳統的歸零碼和反歸零碼,雙二進制反歸零碼具有更大的色散容限,且每個傳輸符號均有能量。我們先研究了它的優勢,調製/解調方法,而後研究了該碼型在無源光網絡中的具體應用,包括10‐Gb/s 全光組播系統和基於重調製的80 公里長距離波分複用無源光網絡系統。 / 第二項研究課題為雙二進制曼切斯特碼型,該碼型的優勢包括較大的時鐘分量,窄帶寬,無直流分量等。我們提出了一種基於直接調製的雙二進制曼切斯特碼產生方法。該方法具有高效,低價,高輸出功率等特點。基於該雙二進制曼切斯特碼發射機,我們實現了70 公里雙向傳輸的波分複用無源光網絡。該系統下行傳輸採用雙二進制曼切斯特碼型,上行傳輸採用直接調製的反射式半導體激光器,所以系統成本大大降低。 / 最後,我們研究了電色散補償技術對於傳統曼切斯特碼型的傳輸性能的改善。所使用的電均衡技術包括前向均衡器、判決反饋均衡器和極大似然估計均衡器。通過離線處理的方法,我們對曼切斯特碼型在三種均衡器下的傳輸性能進行了實驗驗證。研究內容包括前向均衡器和判決反饋均衡器抽頭數的優化、不同採樣率下系統性能、極大似然估計中狀態機個數的影響和不同的曼切斯特接收機的影響等等。 / The increasing demands for bandwidth have aroused a myriad of industry and academic activities in developing high-speed and cost-effective optical networks,among which optical broad band access networks was the main driving force for such growth in recent years. The most promising solution to optical broadband access network is the passive optical network (PON), which is a point-to-multipoint tree-topology network that connects optical line terminal (OLT) with many optical network units (ONUs) via a long fiber feeder and many short distribution fibers. Promising the concept it is, it raises many detailed technical challenges, such as colorless ONUs, burst mode transmission, bi-directional transmission with mitigated backscattering noise, long-reach PON, and integrating network functionalities. All of the technical requirements are motivated by the “original requirements“ of telecommunication -- faster, cheaper, and more robust. / To fulfill the technical requirements, different researchers take different angles to design system and to study the enabling technologies. For example, devices, system architectures, network protocols, etc. In this thesis research, we have tried to deal with one or multiple problems by employing advanced modulation formats for the optical signals. In particular, we have studied IRZ-duobinary, Manchester-duobinary, and Manchester formats, including the modulation/demodulation techniques, transmission properties, and system applications. The research topics are classified according to the type of modulation formats. / In the first topic, IRZ-duobinary format is proposed for optical signal transmission. It has desirable properties of large dispersion tolerance (as compared to conventional RZ/IRZ) and finite optical power in each bit. In this study, we firstly show the advantages of IRZ-duobinary and the corresponding modulation techniques. Then, we demonstrate a 10-Gb/s per channel optical multicast overlay scheme and an 80-km-reach system with re-modulated ONU, both in wavelength division multiplexing (WDM) PON. / In the second topic, Manchester-duobinary format, which has the advantages including easy clock/level recovery, compressed bandwidth, and zero DC component, is studied. We propose an efficient and cost-effective Manchester-duobinary transmitter by properly modulating a chirp managed laser (CML) with electrical Manchester signal. Then, a cost-effective CLS 70-km-Reach full-duplex WDM-PON with downstream 10-Gb/s Manchester-duobinary signal and upstream 1.25-Gb/s re-modulated NRZ-OOK signal is proposed and experimentally demonstrated. This design simultaneously solves the problems of colorless ONU, bi-directional transmission, and long-reach, using cost-effective system design and devices. / Finally, we investigate the performance of electronic dispersion compensation (EDC) technique on 10-Gb/s Manchester coded optical signal, so as to further improve its dispersion tolerance and may enables its applications in long-reach PON. In this study, feed forward equalizer (FFE), decision feedback equalizer (DFE), and maximum-likelihood sequence estimation (MLSE) are employed as the equalizers Utilizing off-line signal processing, the performance of different equalizers with different parameters (number of taps, sampling rates, number of states, etc.) under both cases of single-ended and balanced detection are studied and compared. Experimental results show that the transmission distance of Manchester coded signal can be increased by a factor of three with four-sample-per-symbol FFE-DFE. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liu, Zhixin. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 128-148). / Abstract also in Chinese. / Acknowledgement --- p.1 / Abstract --- p.3 / 摘要 --- p.5 / Table of contents --- p.7 / List of figures and tables --- p.13 / Chapter Chapter 1. --- Introduction / Chapter 1.1 --- Optical Broadband Access --- p.18 / Chapter 1.1.1 --- Bandwidth requirement --- p.19 / Chapter 1.1.2 --- Passive optical networks --- p.22 / Chapter 1.2 --- Research Challenge of Next-Generation Optical Access Network --- p.25 / Chapter 1.2.1 --- Colorless ONU --- p.25 / Chapter 1.2.2 --- Burst Mode Transmission --- p.27 / Chapter 1.2.3 --- Backscattering Noise in PON --- p.28 / Chapter 1.2.4 --- Long-Reach Access Network --- p.30 / Chapter 1.2.5 --- Enriching Network Functionalities --- p.31 / Chapter 1.3 --- Major contribution of this thesis --- p.32 / Chapter 1.3.1 --- IRZ-duobinary transmitter and application --- p.32 / Chapter 1.3.2 --- Manchester-duobinary transmitter and application --- p.33 / Chapter 1.3.3 --- Receiver with electronic equalizer for Manchester signal --- p.34 / Chapter 1.4 --- Outline of this Thesis --- p.35 / Chapter Chapter 2. --- Optical Modulation Technique and Transmission Impairments / Chapter 2.1 --- Optical Modulation techniques --- p.38 / Chapter 2.1.1 --- Chirp managed laser --- p.38 / Chapter 2.1.2 --- Mach-Zehnder modulator --- p.41 / Chapter 2.2 --- Transmission Impairments --- p.47 / Chapter 2.2.1 --- Noise --- p.47 / Chapter 2.2.2 --- Chromatic dispersion --- p.49 / Chapter 2.2.3 --- Fiber nonlinearity --- p.50 / Chapter 2.3 --- Impairment Mitigation Techniques --- p.51 / Chapter 2.3.1 --- In-line compensation techniques --- p.51 / Chapter 2.3.2 --- Post-compensation techniques --- p.52 / Chapter Chapter 3. --- Optical Multicast and Re-modulation Based on Inverse-RZ-duobinary Transmitter / Chapter 3.1 --- Introduction --- p.53 / Chapter 3.2 --- IRZ-duobinary transmitter --- p.55 / Chapter 3.2.1 --- Generation of IRZ-duobinary format --- p.55 / Chapter 3.2.2 --- Comparison of different configurations of IRZ-duobinary generation --- p.56 / Chapter 3.3 --- IRZ-duobinary format for optical multicast in WDM-PON --- p.60 / Chapter 3.3.1 --- Optical multicast in WDM-PON --- p.60 / Chapter 3.3.2 --- Proposed system architecture --- p.61 / Chapter 3.3.3 --- Experimental demonstration of the proposed optical multicast system --- p.65 / Chapter 3.4 --- IRZ-duobinary for long-reach PON --- p.68 / Chapter 3.4.1 --- Long-reach PON using DI based IRZ-duobinary transmitter --- p.69 / Chapter 3.4.2 --- Long-reach PON using CML based IRZ-duobinary transmitter --- p.75 / Chapter 3.5 --- Summary --- p.81 / Chapter Chapter 4. --- Manchester-duobinary Transmitter for Bi-directional WDM-PON / Chapter 4.1 --- Introduction --- p.83 / Chapter 4.2 --- Manchester-duobinary transmitter --- p.85 / Chapter 4.2.1 --- Mach-Zehnder modulator based Manchester-duobinary transmitter --- p.85 / Chapter 4.2.2 --- Chirp managed laser based Manchester-duobinary transmitter --- p.87 / Chapter 4.3 --- Rayleigh noise mitigated bi-directional WDM-PON based on Manchester-duobinary transmitter --- p.94 / Chapter 4.3.1 --- CLS Bi-directional long-reach WDM-PON. --- p.94 / Chapter 4.3.2 --- Proposed system architecture --- p.97 / Chapter 4.3.3 --- Experimental demonstration --- p.99 / Chapter 4.4 --- Summary --- p.102 / Chapter Chapter 5. --- Electronic Equalizer for Manchester Coded Signal / Chapter 5.1 --- Introduction --- p.103 / Chapter 5.2 --- Electronic equalizer for CD compensation --- p.104 / Chapter 5.2.1 --- Channel model --- p.104 / Chapter 5.2.2 --- FFE-DFE --- p.106 / Chapter 5.2.3 --- MLSE --- p.107 / Chapter 5.3 --- FFE-DFE for Manchester signal --- p.109 / Chapter 5.3.1 --- Experimental setup for CD compensation of Manchester signal using FFE-DFE --- p.110 / Chapter 5.3.2 --- Results and discussion --- p.112 / Chapter 5.4 --- MLSE equalizer for Manchester signal --- p.121 / Chapter 5.4.1 --- Experimental setup for CD compensation of Manchester format using MLSE --- p.121 / Chapter 5.4.1 --- Results and discussion --- p.122 / Chapter 5.5 --- Summary --- p.124 / Chapter Chapter 6. --- Conclusion / Chapter 6.1 --- Summary of this thesis --- p.125 / Chapter 6.2 --- Future work --- p.127 / References --- p.128 / Chapter Appendix: --- p.149 / Chapter A. --- List of abbreviations --- p.149 / Chapter B. --- List of publications --- p.154

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