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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.
141

Channel estimation techniques for filter bank multicarrier based transceivers for next generation of wireless networks

Ijiga, Owoicho Emmanuel January 2017 (has links)
A dissertation submitted to Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the degree of Master of Science in Engineering (Electrical and Information Engineering), August 2017 / The fourth generation (4G) of wireless communication system is designed based on the principles of cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) where the cyclic prefix (CP) is used to combat inter-symbol interference (ISI) and inter-carrier interference (ICI) in order to achieve higher data rates in comparison to the previous generations of wireless networks. Various filter bank multicarrier systems have been considered as potential waveforms for the fast emerging next generation (xG) of wireless networks (especially the fifth generation (5G) networks). Some examples of the considered waveforms are orthogonal frequency division multiplexing with offset quadrature amplitude modulation based filter bank, universal filtered multicarrier (UFMC), bi-orthogonal frequency division multiplexing (BFDM) and generalized frequency division multiplexing (GFDM). In perfect reconstruction (PR) or near perfect reconstruction (NPR) filter bank designs, these aforementioned FBMC waveforms adopt the use of well-designed prototype filters (which are used for designing the synthesis and analysis filter banks) so as to either replace or minimize the CP usage of the 4G networks in order to provide higher spectral efficiencies for the overall increment in data rates. The accurate designing of the FIR low-pass prototype filter in NPR filter banks results in minimal signal distortions thus, making the analysis filter bank a time-reversed version of the corresponding synthesis filter bank. However, in non-perfect reconstruction (Non-PR) the analysis filter bank is not directly a time-reversed version of the corresponding synthesis filter bank as the prototype filter impulse response for this system is formulated (in this dissertation) by the introduction of randomly generated errors. Hence, aliasing and amplitude distortions are more prominent for Non-PR. Channel estimation (CE) is used to predict the behaviour of the frequency selective channel and is usually adopted to ensure excellent reconstruction of the transmitted symbols. These techniques can be broadly classified as pilot based, semi-blind and blind channel estimation schemes. In this dissertation, two linear pilot based CE techniques namely the least square (LS) and linear minimum mean square error (LMMSE), and three adaptive channel estimation schemes namely least mean square (LMS), normalized least mean square (NLMS) and recursive least square (RLS) are presented, analyzed and documented. These are implemented while exploiting the near orthogonality properties of offset quadrature amplitude modulation (OQAM) to mitigate the effects of interference for two filter bank waveforms (i.e. OFDM/OQAM and GFDM/OQAM) for the next generation of wireless networks assuming conditions of both NPR and Non-PR in slow and fast frequency selective Rayleigh fading channel. Results obtained from the computer simulations carried out showed that the channel estimation schemes performed better in an NPR filter bank system as compared with Non-PR filter banks. The low performance of Non-PR system is due to the amplitude distortion and aliasing introduced from the random errors generated in the system that is used to design its prototype filters. It can be concluded that RLS, NLMS, LMS, LMMSE and LS channel estimation schemes offered the best normalized mean square error (NMSE) and bit error rate (BER) performances (in decreasing order) for both waveforms assuming both NPR and Non-PR filter banks. Keywords: Channel estimation, Filter bank, OFDM/OQAM, GFDM/OQAM, NPR, Non-PR, 5G, Frequency selective channel. / CK2018
142

A methodology to detect and classify underwater unexploded ordnance in DIDSON sonar images

Unknown Date (has links)
High-resolution sonar systems are primarily used for ocean floor surveys and port security operations but produce images of limited resolution. In turn, a sonar-specific methodology is required to detect and classify underwater unexploded ordnance (UXO) using the low-resolution sonar data. After researching and reviewing numerous approaches the Multiple Aspect-Fixed Range Template Matching (MAFR-TM) algorithm was developed. The MAFR-TM algorithm is specifically designed to detect and classify a target of high characteristic impedance in an environment that contains similar shaped objects of low characteristic impedance. MAFR-TM is tested against a tank and field data set collected by the Sound Metrics Corp. DIDSON US300. This thesis document proves the MAFR-TM can detect, classify, orient, and locate a target in the sector-scan sonar images. This paper focuses on the MAFR-TM algorithm and its results. / by Lisa Nicole Brisson. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
143

Development of a Wearable Device to Detect Epilepsy

Unknown Date (has links)
This paper evaluates the effectiveness of a wearable device, developed by the author, to detect different types of epileptic seizures and monitor epileptic patients. The device uses GSR, Pulse, EMG, body temperature and 3-axis accelerometer sensors to detect epilepsy. The device first learns the signal patterns of the epileptic patient in ideal condition. The signal pattern generated during the epileptic seizure, which are distinct from other signal patterns, are detected and analyzed by the algorithms developed by the author. Based on an analysis, the device successfully detected different types of epileptic seizures. The author conducted an experiment on himself to determine the effectiveness of the device and the algorithms. Based on the simulation results, the algorithms are 100 percent accurate in detecting different types of epileptic seizures. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
144

Source speed estimation using a pilot tone in a high-frequency acoustic modem

Unknown Date (has links)
This thesis proposes to estimate the speed of a moving acoustic source by either linear or non linear processing of the resulting Doppler shift present in a high-frequency pilot tone. The source is an acoustic modem (Hermes) which currently uses moving average to estimate and compensate for Doppler shift. A new auto regressive approach to Doppler estimation (labeled IIR method in the text) promises to give a better estimate. The results for a simulated peak velocity of 2 m/s in the presence of additive noise showed an RMSE of 0.23 m/s using moving average vs. 0.00018 m/s for the auto regressive approach. The SNR was 75 dB. The next objective was to compare the estimated Doppler velocity obtained using the two algorithms with the experimental values recorded in real time. The setup consisted of a receiver hydrophone attached to a towing carriage that moved with a known velocity with respect to a stationary acoustic source. The source transmitted 375 kHz pilot tone. The received pilot tone data were preprocessed using the two algorithms to estimate both Doppler shift and Doppler velocity. The accuracy of the algorithms was compared against the true velocity values of the carriage. The RMSE for a message from experiments conducted indoor for constant velocity of 0.4 m/s was 0.6055 m/s using moving average, 0.0780 m/s using auto regressive approach. The SNIR was 6.3 dB. / by Poorani Kathiroli. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
145

Image improvement using dynamic optical low-pass filter

Unknown Date (has links)
Professional imaging systems, particularly motion picture cameras, usually employ larger photosites and lower pixel counts than many amateur cameras. This results in the desirable characteristics of improved dynamic range, signal to noise and sensitivity. However, high performance optics often have frequency response characteristics that exceed the Nyquist limit of the sensor, which, if not properly addressed, results in aliasing artifacts in the captured image. Most contemporary still and video cameras employ various optically birefringent materials as optical low-pass filters (OLPF) in order to minimize aliasing artifacts in the image. Most OLPFs are designed as optical elements with a frequency response that does not change even if the frequency responses of the other elements of the capturing systems are altered. An extended evaluation of currently used birefringent-based OLPFs is provided. In this work, the author proposed and demonstrated the use of a parallel optical window p ositioned between a lens and a sensor as an OLPF. Controlled X- and Y-axes rotations of the optical window during the image exposure results in a manipulation of the system's point-spread function (PSF). Consequently, changing the PSF affects some portions of the frequency components contained in the image formed on the sensor. The system frequency response is evaluated when various window functions are used to shape the lens' PSF, such as rectangle, triangle, Tukey, Gaussian, Blackman-Harris etc. In addition to the ability to change the PSF, this work demonstrated that the PSF can be manipulated dynamically, which allowed us to modify the PSF to counteract any alteration of other optical elements of the capturing system. There are several instances presented in the dissertation in which it is desirable to change the characteristics of an OLPF in a controlled way. / In these instances, an OLPF whose characteristics can be altered dynamically results in an improvement of the image quality. / by Branko Petljanski. / Thesis (Ph.D.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.
146

The directionality of noise created by turbulent flow over roughness

Unknown Date (has links)
Flow over a rough surface is known to radiate sound as a dipole source that is directional. In order to better understand this source, measurements are being made in a wind tunnel using a microphone array. The measurements collected by a microphone array are beamformed to give a source image and can be deconvolved with an assumed point spread function in order to obtain the source levels. This thesis considers alternative analysis algorithms that can be used to analyze wind tunnel data. Only numerical examples of how these algorithms work will be presented and the analysis of real data will be considered in later studies. It will be shown how estimates can be made of the source directivity by comparing the measured data with a theoretical source model and minimizing the error between the model and the measurements. / by Gerard P. Kaufman. / Thesis (M.S.C.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
147

Characteristics of a detail preserving nonlinear filter.

January 1993 (has links)
by Lai Wai Kuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves [119-125]). / Abstract --- p.i / Acknowledgement --- p.ii / Table of Contents --- p.iii / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Background - The Need for Nonlinear Filtering --- p.1.1 / Chapter 1.2 --- Nonlinear Filtering --- p.1.2 / Chapter 1.3 --- Goal of the Work --- p.1.4 / Chapter 1.4 --- Organization of the Thesis --- p.1.5 / Chapter Chapter 2 --- An Overview of Robust Estimator Based Filters Morphological Filters / Chapter 2.1 --- Introduction --- p.2.1 / Chapter 2.2 --- Signal Representation by Sets --- p.2.2 / Chapter 2.3 --- Robust Estimator Based Filters --- p.2.4 / Chapter 2.3.1 --- Filters based on the L-estimators --- p.2.4 / Chapter 2.3.1.1 --- The Median Filter and its Derivations --- p.2.5 / Chapter 2.3.1.2 --- Rank Order Filters and Derivations --- p.2.9 / Chapter 2.3.2 --- Filters based on the M-estimators (M-Filters) --- p.2.11 / Chapter 2.3.3 --- Filter based on the R-estimators --- p.2.13 / Chapter 2.4 --- Filters based on Mathematical Morphology --- p.2.14 / Chapter 2.4.1 --- Basic Morphological Operators --- p.2.14 / Chapter 2.4.2 --- Morphological Filters --- p.2.18 / Chapter 2.5 --- Chapter Summary --- p.2.20 / Chapter Chapter 3 --- Multi-Structuring Element Erosion Filter / Chapter 3.1 --- Introduction --- p.3.1 / Chapter 3.2 --- Problem Formulation --- p.3.1 / Chapter 3.3 --- Description of Multi-Structuring Element Erosion Filter --- p.3.3 / Chapter 3.3.1 --- Definition of Structuring Element for Multi-Structuring Element Erosion Filter --- p.3.4 / Chapter 3.3.2 --- Binary multi-Structuring Element Erosion Filter --- p.3.9 / Chapter 3.3.3 --- Selective Threshold Decomposition --- p.3.10 / Chapter 3.3.4 --- Multilevel Multi-Structuring Element Erosion Filter --- p.3.15 / Chapter 3.3.5 --- A Combination of Multilevel Multi-Structuring Element Erosion Filter and its Dual --- p.3.21 / Chapter 3.4 --- Chapter Summary --- p.3.21 / Chapter Chapter 4 --- Properties of Multi-Structuring Element Erosion Filter / Chapter 4.1 --- Introduction --- p.4.1 / Chapter 4.2 --- Deterministic Properties --- p.4.2 / Chapter 4.2.1 --- Shape of Invariant Signal --- p.4.3 / Chapter 4.2.1.1 --- Binary Multi-Structuring Element Erosion Filter --- p.4.5 / Chapter 4.2.1.2 --- Multilevel Multi-Structuring Element Erosion Filter --- p.4.16 / Chapter 4.2.2 --- Rate of Convergence of Multi-Structuring Element Erosion Filter --- p.4.25 / Chapter 4.2.2.1 --- Convergent Rate of Binary Multi-Structuring Element Erosion Filter --- p.4.25 / Chapter 4.2.2.2 --- Convergent Rate of Multilevel Multi-Structuring Element Erosion Filter --- p.4.28 / Chapter 4.3 --- Statistical Properties --- p.4.30 / Chapter 4.3.1 --- Output Distribution of Multi-Structuring Element Erosion Filter --- p.4.30 / Chapter 4.3.1.1 --- One-Dimensional Statistical Analysis of Multilevel Multi-Structuring Element Erosion Filter --- p.4.31 / Chapter 4.3.1.2 --- Two-Dimensional Statistical Analysis of Multilevel Multi-Structuring Element Erosion Filter --- p.4.32 / Chapter 4.3.2 --- Discussions on Statistical Properties --- p.4.36 / Chapter 4.4 --- Chapter Summary --- p.4.40 / Chapter Chapter 5 --- Performance Evaluation / Chapter 5.1 --- Introduction --- p.5.1 / Chapter 5.2 --- Performance Criteria --- p.5.2 / Chapter 5.2.1 --- Noise Suppression --- p.5.5 / Chapter 5.2.2 --- Subjective Criterion --- p.5.16 / Chapter 5.2.3 --- Computational Requirement --- p.5.20 / Chapter 5.3 --- Chapter Summary --- p.5.23 / Chapter Chapter 6 --- Recapitulation and Suggestions for Further Work / Chapter 6.1 --- Recapitulation --- p.6.1 / Chapter 6.2 --- Suggestions for Further Work --- p.6.4 / Chapter 6.2.1 --- Probability Measure Function for the Two-Dimensional Filter --- p.6.4 / Chapter 6.2.2 --- Hardware Implementation --- p.6.5 / References / Appendices
148

Split algorithms for LMS adaptive systems.

January 1991 (has links)
by Ho King Choi. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Adaptive Filter and Adaptive System --- p.1 / Chapter 1.2 --- Applications of Adaptive Filter --- p.4 / Chapter 1.2.1 --- System Identification --- p.4 / Chapter 1.2.2 --- Noise Cancellation --- p.6 / Chapter 1.2.3 --- Echo Cancellation --- p.8 / Chapter 1.2.4 --- Speech Processing --- p.10 / Chapter 1.3 --- Chapter Summary --- p.14 / References --- p.15 / Chapter 2. --- Adaptive Filter Structures and Algorithms --- p.17 / Chapter 2.1 --- Filter Structures for Adaptive Filtering --- p.17 / Chapter 2.2 --- Adaptation Algorithms --- p.22 / Chapter 2.2.1 --- The LMS Adaptation Algorithm --- p.24 / Chapter 2.2.1.1 --- Convergence Analysis --- p.28 / Chapter 2.2.1.2 --- Steady State Performance --- p.33 / Chapter 2.2.2 --- The RLS Adaptation Algorithm --- p.35 / Chapter 2.3 --- Chapter Summary --- p.39 / References --- p.41 / Chapter 3. --- Parallel Split Adaptive System --- p.45 / Chapter 3.1 --- Parallel Form Adaptive Filter --- p.45 / Chapter 3.2 --- Joint Process Estimation with a Split-Path Adaptive Filter --- p.49 / Chapter 3.2.1 --- The New Adaptive System Identification Configuration --- p.53 / Chapter 3.2.2 --- Analysis of the Split-Path System Modeling Structure --- p.57 / Chapter 3.2.3 --- Comparison with the Non-Split Configuration --- p.63 / Chapter 3.2.4 --- Some Notes on Even Filter Order Case --- p.67 / Chapter 3.2.5 --- Simulation Results --- p.70 / Chapter 3.3 --- Autoregressive Modeling with a Split-Path Adaptive Filter --- p.75 / Chapter 3.3.1 --- The Split-Path Adaptive Filter for AR Modeling --- p.79 / Chapter 3.3.2 --- Analysis of the Split-Path AR Modeling Structure --- p.84 / Chapter 3.3.3 --- Comparison with Traditional AR Modeling System --- p.89 / Chapter 3.3.4 --- Selection of Step Sizes --- p.90 / Chapter 3.3.5 --- Some Notes on Odd Filter Order Case --- p.94 / Chapter 3.3.6 --- Simulation Results --- p.94 / Chapter 3.3.7 --- Application to Noise Cancellation --- p.99 / Chapter 3.4 --- Chapter Summary --- p.107 / References --- p.109 / Chapter 4. --- Serial Split Adaptive System --- p.112 / Chapter 4.1 --- Serial Form Adaptive Filter --- p.112 / Chapter 4.2 --- Time Delay Estimation with a Serial Split Adaptive Filter --- p.125 / Chapter 4.2.1 --- Adaptive TDE --- p.125 / Chapter 4.2.2 --- Split Filter Approach to Adaptive TDE --- p.132 / Chapter 4.2.3 --- Analysis of the New TDE System --- p.136 / Chapter 4.2.3.1 --- Least-mean-square Solution --- p.138 / Chapter 4.2.3.2 --- Adaptation Algorithm and Performance Evaluation --- p.142 / Chapter 4.2.4 --- Comparison with Traditional Adaptive TDE Method --- p.147 / Chapter 4.2.5 --- System Implementation --- p.148 / Chapter 4.2.6 --- Simulation Results --- p.148 / Chapter 4.2.7 --- Constrained Adaptation for the New TDE System --- p.156 / Chapter 4.3 --- Chapter Summary --- p.163 / References --- p.165 / Chapter 5. --- Extension of the Split Adaptive Systems --- p.167 / Chapter 5.1 --- The Generalized Parallel Split System --- p.167 / Chapter 5.2 --- The Generalized Serial Split System --- p.170 / Chapter 5.3 --- Comparison between the Parallel and the Serial Split Adaptive System --- p.172 / Chapter 5.4 --- Integration of the Two Forms of Split Predictors --- p.177 / Chapter 5.5 --- Application of the Integrated Split Model to Speech Encoding --- p.179 / Chapter 5.6 --- Chapter Summary --- p.188 / References --- p.139 / Chapter 6. --- Conclusions --- p.191 / References --- p.197
149

Amplifier linearization by using the generalized baseband signal injection method.

January 2002 (has links)
Leung Chi-Shuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 82-89). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Review of Linearization Techniques --- p.4 / Chapter 2.1 --- Feedforward --- p.5 / Chapter 2.2 --- Feedback --- p.7 / Chapter 2.3 --- Predistortion --- p.10 / Chapter Chapter 3 --- The Volterra Series Method for Nonlinear Analysis --- p.12 / Chapter 3.1 --- Volterra Series Method --- p.13 / Chapter 3.2 --- Nonlinear Transfer Function --- p.14 / Chapter 3.3 --- Weakly Nonlinear Approximation --- p.18 / Chapter 3.4 --- Nonlinear Modeling --- p.19 / Chapter 3.5 --- Determination of Nonlinear Transfer Function --- p.22 / Chapter Chapter 4 --- Manifestation of Nonlinear Behavior --- p.25 / Chapter 4.1 --- Two-Tone Volterra Series Analysis --- p.25 / Chapter 4.2 --- Harmonic Distortion --- p.28 / Chapter 4.3 --- AM/AM and AM/PM --- p.29 / Chapter 4.4 --- Intermodulation Distortion --- p.31 / Chapter Chapter 5 --- The Generalized Baseband Signal Injection Method --- p.33 / Chapter 5.1 --- Generalized Baseband Signal Injection Method (GM) --- p.34 / Chapter 5.2 --- Application of GM to Predistorter-Amplifier Linearization --- p.38 / Chapter 5.2.1 --- Case 1: Standalone Amplifier without Injection --- p.40 / Chapter 5.2.2 --- Case 2: Injection to Amplifier Only --- p.41 / Chapter 5.2.3 --- Case 3: Injection to Diode Predistorter Only --- p.41 / Chapter 5.2.4 --- Case 4: Injection to Both Diode Predistorter and Amplifier --- p.42 / Chapter 5.3 --- Application of GM to Multi-Stage Amplifier Linearization --- p.43 / Chapter 5.3.1 --- Case 1: Amplifying System with No Signal Injection --- p.46 / Chapter 5.3.2 --- Case 2: Amplifying System with Single Injection Point --- p.47 / Chapter 5.3.3 --- Case 3: Amplifying System with Two Injection Points --- p.48 / Chapter Chapter 6 --- Experimental Setup and Measurements --- p.50 / Chapter 6.1 --- Experimental Setup --- p.51 / Chapter 6.1.1 --- Diode Predistorter --- p.51 / Chapter 6.1.2 --- Small Signal Amplifier --- p.54 / Chapter 6.1.3 --- Medium Power Amplifier --- p.58 / Chapter 6.1.4 --- Baseband Signal Generation Circuit --- p.61 / Chapter 6.1.5 --- Baseband Amplifiers --- p.63 / Chapter 6.2 --- Linearization of Amplifier with Predistortion Circuitry --- p.65 / Chapter 6.2.1 --- Two-Tone Test --- p.65 / Chapter 6.2.2 --- Vector Signal Test --- p.68 / Chapter 6.2.3 --- Dynamic Range Evaluation --- p.70 / Chapter 6.3 --- Linearization of Multi-Stage Amplifying System --- p.71 / Chapter 6.3.1 --- Determination of Transfer and Gain Coefficients --- p.71 / Chapter 6.3.2 --- Two-Tone Test --- p.74 / Chapter 6.3.3 --- Vector Signal Test --- p.77 / Chapter 6.3.4 --- Dynamic Range Evaluation --- p.79 / Chapter Chapter 7 --- Conclusion and Future Work --- p.80 / References --- p.82 / Author's Publications --- p.90
150

A low-cost active RFID indoor locationing system using phased array technology. / Low-cost active radio frequency identification indoor locationing system using phased array technology

January 2012 (has links)
近十年來,無線通訊技術、流動電話服務以及無線網絡的發展一日千里。不單止為社會帶來很多新的技術及先進的設備,更加帶來了許多新穎的應用構想。其中最被廣泛討論的要數室內無線實時定位系統。室內定位,顧名思義就是一種對一個或多個室內目標進行定位及追蹤的技術。這種技術的潛在應用非常多元化,例如倉庫管理、人力資源調配等等。透過這種技術可以使一些室內位置信息相關的服務更加自動化,從而提升服務效率。正因為市場狂熱的需求,近年來室內無線實時定位系統一直都是一個熱門的研究課題。 / 本論文的上半部主要是討論一種基於無線射頻識別技術的室內無線實時定位系統。這個系統的特點是在閱讀器的天線上應用了模擬一維綫相控陣列天線。系統的定位原理是基於三角測距法,透過相控陣的主波束掃描配合信號強度測量去估算出信號入射角。比較其他入射角測量的方法,應用這種方法的硬件成本更低而且能確保一定的精度。整個系統的開發包括有無線射頻標籤、閱讀器、模擬一維綫相控陣列天線、網絡控制器、數據庫、圖像應用界面及一種有效壓抑室內多徑問題的定位算法。這個系統的最大好處就是它不像其他一些現存的定位系統一樣,在安裝後需要進行大量的離線實地校準。我們進行了大量的實驗去客觀地驗證系統的定位性能,實驗的結果指出系統的定位誤差平均值小於一米。 / 為了控制系統的硬件成本,上述所提及到的模擬一維綫相控陣列天線會採用一種非常便宜的板材:FR4。但是FR4這種板材便宜的代價便是它相對較高的介質損耗。較高的介質損耗對模擬一維綫相控陣列天線的實現存在着一個重要的難題:模擬360º移相器的插入損耗相對電壓變化不平滑。有見及止,本論文的下半部會討論一種新穎而有效壓抑因高介質損耗而導致插入損耗不平滑的反射式移相器。新的移相器設計包含兩種壓抑插入損耗不平滑的技術。在仿真結果中,新的設計把傳統設計的插入損耗不平滑從1.4分貝大幅降低至0.3分貝。實驗的結果指出,在360o 的移相範圍內只存在着0.6分貝的插入損耗不平滑。 / 最後在此作一個總結。本論文主要是討論一種高效、低成本、基於無線射頻識別技術及模擬一維綫相控陣列天線技術的室內無線實時定位系統。大量的實驗數據證明了它良好的定位性能。而且系統的網絡設計使到它可以更彈性地應用到不同的場所。 / In recent years, the rapid development in wireless communication technologies, mobile computing devices and wireless networks has stimulated a fast growing interest in various location-aware systems that can provide real time information of physical locations of objects or persons. In this thesis, an active radio frequency identification (RFID) indoor positioning system utilizing analog linear phased array antenna (PAA) technology has been proposed and demonstrated. By using beam steering of an analog linear PAA and measuring the corresponding received signal strength indicator (RSSI), one can determine the angle of arrival (AoA) of the transmitted signal from a tag. In this work, a complete locationing system has been built, which includes RFID tag, reader integrated PAA, network controller and database with event driven functions. Besides that, a novel positioning algorithm that can effectively overcome indoor multipath effect is also proposed. The major advantage of the proposed system is that it doesn’t require any on-site calibration. Therefore, the setup of the proposed system is scenario-independent. A large number of experiments and results have demonstrated that the probabilities of spatial errors of less than 1 meter and 1.5 meters of the proposed system are about 80% and 95% respectively. / In order to have a cost-effective system, those analog linear PAAs are fabricated in FR4 substrate, with which constant insertion loss under phase steering of a 360º analog phase shifter is difficult to realize due to the substrate loss. In order to overcome this difficulty, a novel loss-compensated microstrip 360º reflection-type diode phase shifter with constant insertion loss has been proposed and concept proven. In this regard, two techniques have been investigated to reduce the insertion loss variation which is caused by using lossy substrate. As compared with the conventional design, simulation results have shown a considerable improvement on the insertion loss variation from 1.4dB to 0.3dB. Measurement results have demonstrated a 0.6dB insertion loss variation over 360º phase steering range. / In conclusion, a low-cost but with moderate performance RFID indoor locationing system based on analog linear PAA technology has been proposed and experimentally demonstrated. The prototype system has shown its high accuracy, flexibility in network deployment, and scenario-independent operation. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Hung, Wing Hung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 85-87). / Abstracts also in Chinese. / ABSTRACT --- p.I / 論文摘要 --- p.III / ACKNOWLEDGEMENT --- p.V / TABLE OF CONTENT --- p.VI / LIST OF FIGURES --- p.IX / LIST OF TABLES --- p.XIII / LIST OF ABBREVIATIONS --- p.XIV / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1. --- RESEARCH MOTIVATION --- p.1 / Chapter 1.2. --- OVERVIEW OF THE THESIS ORGANIZATION --- p.5 / Chapter CHAPTER 2 --- FUNDAMENTALS IN LINEAR PHASED ARRAY ANTENNA AND REFLECTION-TYPE PHASE SHIFTER --- p.6 / Chapter 2.1. --- LINEAR PHASED ARRAY ANTENNA --- p.6 / Chapter 2.1.1. --- Operating Principle --- p.7 / Chapter 2.1.2. --- Simulation Example --- p.9 / Chapter 2.2. --- REFLECTION-TYPE PHASE SHIFTER --- p.10 / Chapter 2.2.1. --- Operating Principle --- p.10 / Chapter 2.2.2. --- Simulation Example --- p.12 / Chapter CHAPTER 3 --- CONVENTIONAL INDOOR POSITIONING METHODOLOGIES --- p.15 / Chapter 3.1. --- RSSI RANGING --- p.15 / Chapter 3.1.1. --- Radio Fingerprint --- p.15 / Chapter 3.1.2. --- Radio Propagation Model --- p.17 / Chapter 3.1.3. --- Reference Tags --- p.18 / Chapter 3.1.4. --- Ordered Signal Strength Sequence --- p.19 / Chapter 3.2. --- UWB RANGING --- p.20 / Chapter 3.3. --- NEAR FIELD ELECTROMAGNETIC RANGING (NFER) --- p.21 / Chapter CHAPTER 4 --- CONVENTIONAL 360º REFLECTION-TYPE PHASE SHIFTER DESIGNS --- p.23 / Chapter 4.1. --- PARALLELING TWO SERIES-RESONANT VARACTOR CIRCUIT --- p.23 / Chapter 4.1.1. --- 360º Phase Shift --- p.24 / Chapter 4.1.2. --- Constant Insertion Loss --- p.24 / Chapter 4.1.3. --- Performance --- p.25 / Chapter 4.2. --- PARALLELING TWO ARMS HAVING 180O PHASE CHANGE WITH 90º OUT OF PHASE --- p.27 / Chapter 4.2.1. --- Linearity and 180º Phase Shift --- p.27 / Chapter 4.2.2. --- Constant Insertion Loss --- p.29 / Chapter 4.2.3. --- 360º Phase Shift --- p.29 / Chapter 4.2.4. --- Performance --- p.30 / Chapter 4.3. --- CONNECTING TWO ARMS HAVING 180O PHASE CHANGE WITH 90O OUT OF PHASE IN-SERIES --- p.31 / Chapter 4.3.1. --- Constant Insertion Loss --- p.31 / Chapter 4.3.2. --- 360º Phase Shift --- p.32 / Chapter 4.3.3. --- Performance --- p.32 / Chapter CHAPTER 5 --- AN ACTIVE RFID INDOOR POSITIONING SYSTEM UTILIZING ANALOG LINEAR PHASED ARRAY --- p.34 / Chapter 5.1. --- POSITIONING METHODOLOGY --- p.35 / Chapter 5.2. --- SYSTEM ARCHITECTURE --- p.37 / Chapter 5.2.1. --- Analog Linear Phased Array Antenna --- p.39 / Chapter 5.3. --- POSITIONING ALGORITHM --- p.51 / Chapter 5.3.1. --- Zone Decision --- p.51 / Chapter 5.3.2. --- Point Location --- p.52 / Chapter 5.4. --- EXPERIMENTAL RESULT --- p.58 / Chapter CHAPTER 6 --- NOVEL 360º REFLECTION-TYPE DIODE PHASE SHIFTER WITH CONSTANT INSERTION LOSS UNDER LOSSY SUBSTRATE --- p.65 / Chapter 6.1. --- REVIEW --- p.66 / Chapter 6.2. --- PROBLEMS --- p.68 / Chapter 6.3. --- PROPOSED SOLUTIONS --- p.71 / Chapter 6.3.1. --- Closed Reflection Coefficient Circle --- p.71 / Chapter 6.3.2. --- Centered Reflection Coefficient Circle --- p.74 / Chapter 6.4. --- SIMULATION AND MEASUREMENT RESULT --- p.77 / Chapter CHAPTER 7 --- CONCLUSION --- p.83 / REFERENCES --- p.85 / AUTHOR’S PUBLICATIONS --- p.88 / Chapter APPENDIX 1: --- DESIGN OF RFID TAG --- p.89 / Chapter APPENDIX 2: --- DESIGN OF RFID READER --- p.98 / Chapter APPENDIX 3: --- DESIGN OF RFID CONTROLLER --- p.100

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