Dissertations / Theses on the topic 'Frequency-shift keying modulation'

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>The aeronautical telemetry community is investigating alternative modulation methods to the commonly used non-return-to-zero (NRZ) pulse code modulation (PCM)/frequency modulation (FM). This paper outlines the important characteristics being investigated. Measured data comparing the spectral occupancy and bit error probability (BEP) performance of PCM/FM with that of a prototype constant envelope Feher’s quadrature phase shift keying (FQPSK) modulator and demodulator will also be presented. Measured results in several radio frequency bands demonstrate that the 99.99% and -60 dBc bandwidths of filtered FQPSK are only approximately one-half of the corresponding bandwidths of optimized PCM/FM even when the signal is non-linearly amplified. The signal energy per bit to noise power spectral density (E /N ) required for a BEP of 1×10 b 0 -5 for non-optimized FQPSK was approximately 12 dB which is approximately the same as limiter discriminator detected PCM/FM.

Thesis (MScEng)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: This thesis investigates orthogonal frequency division multiplexing (OFDM) as a viable modulation technique for an ultrasonic acoustic underwater modem. The underwater environment provides a challenging setting for acoustic communications. Long delay spreads due to multipath propagation, severe Doppler frequency shifts, frequency dependent absorption and very limited bandwidth are but some of the challenges to overcome. OFDM essentially provides the parallel transmission of symbols in the frequency domain by simultaneously modulating many closely spaced orthogonal subcarriers. The resulting long parallel symbol rate together with the cyclic extension of symbols render the signal robust against intersymbol interference (ISI) caused by multipath propagation. Intercarrier interference (ICI) between the overlapping frequency responses of subcarriers is mitigated by their property of orthogonality. Doppler spread contributes to the loss of orthogonality and can result in severe ICI. A method of measuring the Doppler shift by means of including a preamble and postamble symbol with each data frame is proposed. The detected frequency offset is corrected by resampling the frame at the desired sample rate. Not only do the ambles serve as a mechanism for timing and frequency synchronisation, but they are also applied in the channel estimation process. The equalisation of channel response is required for the coherent demodulation of the received symbols. An investigation into different phase shift keying (PSK) and quadrature amplitude modulation (QAM) constellations reveal optimal arrangements for minimal symbol errors. The optimised QAM constellations do not lend themselves to Gray-coding, so that an efficient interleaving scheme is needed to mitigate the non-uniform distribution of bit errors among symbol errors. Forward error correction is provided via a Bose Chaudhuri Hocquenghem (BCH) block code. Variable code rates, together with the ability to switch between different constellations, enable the modem to perform so-called variable modulation in an attempt to maximise the throughput under specific channel conditions. The modulation/demodulation scheme is wholly defined in software as to provide flexibility and facilitate experimentation with different signal processing methods. The accompanying hardware platform allows for the transmission of a pre-generated signal and the recording of a received signal for off-line processing. The prototype design serves as a proof of concept and thus provides only simplex communication. Field tests over limited distances demonstrate the successful operation of the prototype modem. We conclude that OFDM is indeed a suitable modulation technique for acoustic underwater communication.<br>AFRIKAANSE OPSOMMING: Hierdie tesis ondersoek die toepassing van ortogonale frekwensiedeling multipleksering (OFDM) as modulasie tegniek op ʼn onderwater kommunikasie modem. Die onderwater omgewing bied vele uitdagings vir akoestiese kommunikasie. Lang vertraging-verstrooiings as gevolg van multipad voortplanting, Doppler frekwensieskuif, frekwensieafhanklike absorpsie, en beperkte bandwydte is van die uitdagings wat oorkom moet word. In essensie bied OFDM die parallelle versending van ʼn aantal simbole deur die gelyktydige modulasie van verskeie nou-gespasieerde subdraers in die frekwensiegebied. Die gevolglike lang parallelle simboolperiodes, tesame met die sikliese uitbreiding van simbole, verleen immuniteit teen intersimbool steurnisse (ISI) wat ontstaan as gevolg van multipad voortplanting. Die ortogonaliteit van naburige draers in die frekwensiegebied beperk interdraer steuring (ICI) tussen hul oorvleuelende frekwensie weergawes. Doppler frekwensieskuif kan egter lei tot die verlies aan ortogonaliteit en bydra tot ernstige interdraer steurings. ʼn Metode wat gebruik maak van aanhef en slot simbole, ingesluit by elke raam, word voorgestel om die Dopplerskuif te meet. Die bepaalde frekwensieafset word gekorrigeer deur die monstertempo van die raam aan te pas na die verlangde tempo. Buiten die tyd- en frekwensie-sinkronisasie funksies van die aanhef en slot simbole, speel dit ook ʼn belangrike rol in die ontrekking van die frekwensie weergawe van die kanaal. Die effening van die kanaal se frekwensieweergawe is noodsaaklik vir die koherente demodulasie van die ontvangde simbole. ʼn Ondersoek na verskillende fase verskuif sleuteling (PSK) en kwadratuur amplitude modulasie (QAM) konstellasies het optimale rangskikkings opgelewer vir minimale simboolfoute. Hierdie optimale QAM konstellasies verleen hulself egter nie na Gray-kodering nie. ʼn Effektiewe invlegtegniek is nodig om die nie-uniforme verspreiding van bisfoute tussen simboolfoute te beperk. Fout korrigering funksionaliteit word gebied deur ʼn Bose Chaudhuri Hocquenghem (BCH) blokkode. Verstelbare koderingstempo’s en die vermoë om tussen verskillende konstellasies te skakel, stel die modem in staat om sogenaamde verstelbare modulasie te gebruik in ʼn poging om die data deurset te optimeer onder spesifieke kanaal kondisies. Die modulasie en demodulasie skema is volledig in sagteware gedefinieer. Dit verleen buigbaarheid en vergemaklik eksperimentering met verskeie seinverwerkingstegnieke. Die meegaande hardeware platvorm stel die modem in staat om vooraf opgewekte seine uit te saai en rou ontvangde siene op te neem vir na-tydse verwerking. Die prototipe ontwerp dien as ʼn konseptuele bewys en bied dus slegs simplekse kommunikasie. Die suksesvolle werking van die modem is gedemonstreer deur toetsing oor beperkte afstande. Hieruit word afgelei dat OFDM inderdaad geskik is vir akoestiese onderwater kommunikasie.

Les Oscillateurs Spintronique (STNO) sont un nouveau type d'oscillateurs à fréquence radio (RF) qui utilisent l'effet « Spin Transfer Torque (STT) » dans un dispositif de jonction tunnel magnétique (MTJ) pour produire des oscillations entretenues à haute fréquence. Les STNO fournissent des solutions compactes pour la communication sans fil utilisées dans « wireless sensor network (WSN) » car leur fréquence peut être réglée via un courant continu. Ce réglage de fréquence permet de coder l'information via « Frequency shift keying (FSK) » par modulation numérique entre deux valeurs discrètes sans besoin d'un RF mixer, ce qui conduit à des composants RF potentiellement moins complexes. Dans cette thèse, la faisabilité de FSK a été étudiée pour des STNO MTJ à aimantation dans le plan en vue des communications sans fil utilisées dans les WSN. Les paramètres abordés dans cette étude sont le décalage de fréquence et le taux de modulation maximum, auquel la fréquence peut être décalée entre deux valeurs discrètes.Pour caractériser le taux de modulation maximum, des simulations macrospin et des études expérimentales ont été réalisées. Les simulations révèlent que le taux de modulation maximum pour FSK par courant est limité par la fréquence de relaxation du STNO, qui est de l'ordre de quelques centaines de MHz pour les STNO à aimantation dans le plan. Cela signifie que le taux de modulation maximum est limité à quelques centaines de Mbps, ce qui est ciblé ici pour une communication sans fil à débit de données modéré utilisées dans les WSN. Des études expérimentales du FSK par modulation de courant dans les STNO ont été effectuées pour des STNO autonomes et pour des STNO intégrés dans des systèmes hyperfréquences. Le FSK sur les STNO autonomes montre un décalage de fréquence autour de 200 MHz (le décalage de fréquence entre ≈ 8,9 GHz et ≈9,1 GHz) au taux de modulation de 10Mbps. Ce taux de modulation est inférieur à la limite supérieure donnée par la fréquence de relaxation du STNO comme prévu dans la simulation numérique en raison du bruit de phase relativement élevé du dispositif mesuré. Afin de tester la faisabilité du STNO dans les systèmes hyperfréquences, la modulation FSK des STNO a été effectuée sur un émetteur de carte de circuit imprimé (PCB). L'émetteur de PCB a été réalisé et développé par le partenaire du projet Mosaic FP7, TUD University. L'analyse confirme qu'un changement de fréquence autour de 300 MHz (le décalage de fréquence entre ≈9 GHz et ≈9,3 GHz) a été observé avec un taux de modulation de 20 Mbps. Le taux de données est limité par les caractéristiques de l'émetteur de PCB et non intrinsèque au STNO. Les études de simulation et d'expérience de la modulation de fréquence des STNO démontrent que le débit de données est adéquat pour la communication sans fil utilisée dans WSN.Cependant, d'autres améliorations dans les matériaux et la nanofabrication de STNO sont nécessaires pour améliorer la puissance de sortie et améliorer les caractéristiques spectrales des oscillations pour pousser les débits de données à des valeurs plus élevées avec un grand décalage de fréquence<br>Spin Transfer Nano-Oscillators (STNOs) are a novel type of Radio Frequency (RF) oscillators that make use of the Spin Transfer Torque (STT) effect in a magnetic tunnel junction (MTJ) device to produce high-frequency auto-oscillations. STNOs are attractive for applications in wireless communications due to their nanometric size and their frequency tuning capabilities via either a dc current or an applied field. This frequency tuning permits to encode the information via frequency shift keying (FSK) by digital modulation of the current or applied field between two discrete values without the need of an external RF mixer, leading to potentially less complex RF components. In this thesis, the feasibility of the digital frequency modulation (frequency shift keying (FSK)) using in-plane magnetized MTJ STNOs has been studied. For this, the maximum modulation rate, up to which a signal can be modulated or the frequency can be shifted between two discrete values, is an important aspect that need to be characterized.The characterization of the maximum modulation rate for in-plane magnetized MTJ STNOs has been studied via numerical macrospin simulation for different modulation configurations, i.e. modulation by a sinusoidal RF current and a sinusoidal RF field. It revealed that the maximum modulation rate under RF current modulation is given by the amplitude relaxation frequency fp of the STNO. Under RF field modulation, i.e. an RF field applied parallel to the easy axis, an enhanced modulation rate above fp can be achieved since the frequency is modulated directly via the field and not via the amplitude. This suggests an important strategy for the design of STNO-based wireless communications and to achieve high data rates. Besides numerical simulation, experimental studies of frequency shift keying (FSK) by current modulation in STNOs have been also demonstrated. The first demonstration is the FSK in standalone STNOs. The analysis confirmed that the FSK was successfully observed with a frequency shift around 200MHz (the frequency shift between ≈8.9 GHz and ≈9.1 GHz) at the modulation rate of 10Mbps. This modulation rate is however less than the upper limit, which is given by the relaxation frequency fp of the STNO as predicted in the numerical simulation, because of the relatively high phase noise of the device measured. In order to test the feasibility of the STNO within microwave systems, the FSK modulation of STNOs was performed on a printed circuit board (PCB) emitter. FSK with a frequency shift around 300MHz (the frequency shift between ≈9 GHz and ≈9.3 GHz) was observed with a modulation rate of 20 Mbps. The data rate here was limited by characteristics of the PCB emitter and not intrinsic to the STNO. The simulation and experiment studies of frequency modulation of STNOs demonstrate that the data rate of is adequate for wireless communication used in WSN. However, further improvements in materials and nanofabrication of STNOs are required to enhance the output power and improve the spectral characteristics of the oscillations to push the data rates to higher values with large frequency shift

Railway signaling is of paramount importance to ensure traffic management andsafety on the rail network. The main lines are divided into sections called ‘blocks’,which are governed by a fixed signal installation. To prevent trains from colliding,each block allows one train at once. In France (and most European countries),train detection is performed by an electrical device called track circuit that consistsof a transmitter and a receiver installed at the track-side, and connected via therails. In the absence of a train, an electrical signal flows from the transmitter tothe receiver through the rails. As a train enters a track circuit, its axles shuntthe rails, provoking a short circuit (also called ‘shunt’): the signal transmitted tothe receiver drops. The detection of that signal drop results in the detection of atrain. This method rarely fails throughout the network, but there can be criticalcases where it may be inefficient. In this Master’s Thesis, new detection criteriaproposed in previous studies have been tested on signals measured in poor shuntingconditions. Three approaches have been tested: one in the time domain and two inthe frequency domain. The time approach compares the short-term and long-termstatistics of the received signals. The observation of a change in the spectra of thereceived signals around the 3rd order harmonic (3OH) has led to the implementationof two frequency criteria: the estimation of the band power around the 3OH andthe detection of the 3OH peaks. The obtained results show that better detection isachieved when the new criteria and the existing one are combined.<br>Tågsignalsystem är väsentliga för att garantera trafikstyrning och säkerhet i tågnätet.Spåren är indelade i sektioner, s.k. block, som övervakas med fasta signalinstallationer.För att hindra tåg från att krocka, tillåts bara ett tåg i taget per block. IFrankrike (och de flesta andra europeiska länder), detekteras tågen med en elektriskspårkrets som består av en sändare och en mottagare som är installerad bredvidspåret och ansluten till rälsen. När inget tåg finns på spåret, flyter en elektrisk signalfrån sändaren till mottagaren via spåret. När ett tåg anländer, kortsluts kretsenav hjulaxeln och signalen försvinner från mottagaren. Minskningen i signalstyrkaanvänds för att detektera tåget. Denna metod sällan misslyckas i tågnätet, men iovanliga fall kan det uppstå farliga situationer. I detta examensarbete utvärderasnya detektionsmetoder, som har föreslagits i tidigare studier, på signaler som haruppmätts under förhållanden med dålig kontakt mellan hjul och spår. Tre olika metoderhar testats, en i tidsdomänen och två i frekvensdomänen. Tidsdomänsmetodenjämför kortvarig och långvarig statistik för den mottagna signalen. I spektrum förden mottagna signalen, har man observerat en förändring runt den tredje övertonen,samt detektering av frekvenstoppar vid tredje övertonen. De erhållna resultatenvisar på förbättrad detektering när de nya och existerande kriterierna kombineras.

La manipulation de l’aimantation est un des sujets de recherche les plus étudiés dans le domaine de l’électronique de spin. Différentes méthodes de manipulations peuvent exciter les propriétés dynamiques de l’aimantation à différentes échelles de temps. Parmi les phénomènes dynamiques, la précession de l’aimantation et la désaimantation ultrarapide ont suscité un intérêt particulier. La fréquence de précession de l’aimantation est de l’ordre du GHz et correspond à une période de centaines de picosecondes. Cette précession est le mécanisme à l’œuvre dans les nano-oscillateurs à transfert de spin (NOTS), un nouveau type de dispositif microonde présentant des avantages sur l’oscillateur commandé en tension (OCT) conventionnel en termes de taille, de consommation d’énergie et d’adaptabilité de la fréquence. La désaimantation ultrarapide a été observé pour la première fois dans du nickel en quelques centaines de femtosecondes. Le renversement tout optique (RTO), nécessitant la désaimantation ultrarapide, a ensuite été démontré expérimentalement. Le RTO est bien plus rapide que tout autre retournement de l’aimantation par couple et est donc prometteur pour construire des mémoires magnétiques ultrarapides. Bien que de nombreuses études sur ces deux phénomènes existent, plusieurs problèmes se doivent d’être résolus avant de pouvoir passer à l’étape de production industrielle. Les NOTS sont censés être utilisés pour la modulation par déplacement d’amplitude (MDA) ou la modulation par déplacement de fréquence (MDF), mais les conditions optimales pour ces deux types de modulation microondes n’ont pas encore été assez investiguées. Quant au RTO, l’influence des paramètres du laser tels que la fluence ou la durée de l’impulsion et des propriétés du matériau tels que le composition et l’épaisseur n’a pas fait l’objet d’études systématique. Dans ce manuscrit, ces deux types de manipulation de l’aimantation sont étudiés en détail. En ce qui concerne la précession de l’aimantation, nous démontrons qu’un champ magnétique accru permet d’obtenir une plus large plage de fréquence possible alors qu’un champ magnétique plus faible résulte en une plage d’amplitude possible élargie. Ainsi ces deux scenarii sont applicables au MDF et MDA, respectivement, et posent les bases d’une utilisation des NOTS en modulation microonde. Dans la deuxième étude, nous démontrons que le RTO dépends fortement des caractéristiques de l’impulsion laser. Pour cela nous avons construit un diagramme d’état pour le GdFeCo et le Co/Pt, deux matériaux typiques respectivement du retournement tout optique indépendant de l’hélicité (RTO-IH) et du retournement tout optique dépendant de l’hélicité (RTO-DH). Ces résultats permettent une meilleure compréhension du mécanisme fondamental régissant la dynamique de l’aimantation induite par exposition à un laser<br>Magnetization manipulation is one of the most actively researched topics in the field of spintronics. Different ways of manipulation can trigger magnetization dynamics on different time scales. Among these dynamics, magnetization precession and ultrafast demagnetization have attracted substantial interests. The frequency of magnetization precession is normally in the GHz range corresponding to a period of hundreds of ps, which is the basic mechanism of spin torque nano-oscillators (STNO), a new type of microwave devices which show advantages over conventional voltage-controlled oscillator (VCO) in terms of size, energy consumption and tunable frequency. Ultrafast demagnetization was first observed in Ni which takes places in hundreds of femtoseconds. Triggered by this, All-Optical Switching (AOS) was then demonstrated which is much faster than any torque induced switching, promising for application in the high-speed magnetic memory. Although many studies on these two phenomena have been reported, several issues need to be addressed before they move toward application. STNOs are supposed to be used for amplitude shift keying (ASK) or frequency shift keying (FSK), but the optimal conditions for these two types of microwave modulation are still not well explored. As for AOS, the influence of the laser parameters such as fluence and pulse duration and the material properties such as the composition and the thickness has not been systematically investigated. In this thesis, these two types of magnetization manipulation are studied in detail. Concerning magnetization precession, we demonstrate that a stronger magnetic field allows a wider frequency tuning range while a smaller magnetic field results in a wider amplitude tuning range. Thus, these two scenarios are applicable to FSK and ASK, respectively, providing guidelines for STNO in microwave modulation. In the second study, we demonstrate that AOS depends strongly on pulse characteristic. This was shown by building a magnetization state diagram for GdFeCo and Co/Pt which are two typical materials showing All-Optical Helicity-Independent Switching (AO-HIS) and All-Optical Helicity-Dependent Switching (AO-HDS), respectively. These results allow a better understanding of the fundamental mechanism behind laser-induced magnetization dynamics

Un imageur electromagnetique haute resolution est envisage afin de detecter et de localiser des objets situes dans des structures heterogenes. Il doit permettre la mesure non destructive de contrastes en permittivite et en conductivite, a une profondeur d'investigation de quelques decimetres, avec une resolution de l'ordre du centimetre. Dans ce but, nous cherchons a identifier les points delicats de son developpement. Afin de choisir le systeme et interpreter sa reponse, nous etudions la caracterisation electromagnetique de materiaux, et les phenomenes de reflexions secondaires et de resonance presents dans les milieux formant les structures considerees. Ceci nous permet de specifier un systeme electromagnetique base sur le principe d'un radar a sauts de frequence. Les antennes etant placees a proximite du milieu, nous nous interessons aux phenomenes de couplage afin d'evaluer quelles sont les perturbations induites sur une reponse radar. Des algorithmes d'imagerie qualitative (focalisation par synthese d'ouverture, migration f-k, tomographie microonde) sont utilises afin d'interpreter la reponse de l'imageur sous forme de courants induits. Ils permettent de positionner les structures et les objets cherches. Nous proposons l'emploi de methodes parametriques (methode de pencil) afin d'ameliorer la resolution. Enfin, des experimentations sur des milieux heterogenes avec differentes polarisations et bandes de frequence montrent la validite et les limites de cet imageur.

Deng Ning.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 2004.<br>Includes bibliographical references (leaves 62-65).<br>Abstracts in English and Chinese.<br>ABSTRACT --- p.iii<br>摘要 --- p.v<br>Chapter 1 --- BACKGROUND AND INTRODUCTION --- p.1<br>Chapter 1.1 --- Optical Frequency-Shift Keying (FSK) --- p.1<br>Chapter 1.1.1 --- Basic concepts and research hotspots of optical FSK --- p.1<br>Chapter 1.1.2 --- Optical FSK Transmitter and Receiver --- p.3<br>Chapter 1.2 --- Wavelength Division Multiplexing Optical Passive Networks --- p.8<br>Chapter 1.3 --- Optical Label Switching (OLS) Networks --- p.10<br>Chapter 1.4 --- Thesis Contribution and Organization --- p.11<br>Chapter 2 --- DATA RE-MODULATION ON DOWNSTREAM OPTICAL FSK SIGNALS IN WDM-PONS --- p.12<br>Chapter 2.1 --- overview of related works --- p.12<br>Chapter 2.2 --- PON ARCHITIiCTURE USING DOWNSTREAM OPTICAL FSK SIGNALS --- p.13<br>Chapter 2.3 --- CLS PON DEMONSTRATION USING THREE DIFFERENT OPTICAL FSK TRANSMITTERS --- p.14<br>Chapter 2.3.1 --- With an optical FSK transmitter based on direct modulation in a DFB laser --- p.14<br>Chapter 2.3.2 --- With an optical FSK transmitter based on complementary intensity modulation --- p.17<br>Chapter 2.3.3 --- With our proposed optical FSK transmitter based on phase modulation --- p.21<br>Chapter 2.4 --- System Performance by Using Phase Modulation Based FSK Transmitter…… --- p.26<br>Chapter 2.4.1 --- Wavelength detune of light sources --- p.27<br>Chapter 2.4.2 --- Detune of the DI frequency response --- p.29<br>Chapter 2.4.3 --- Dispersion tolerance --- p.30<br>Chapter 2.5 --- Summary --- p.32<br>Chapter 3 --- INTENSITY-MODULATED LABELLING ON OPTICAL FSK OR DPSK PAYLOADS IN OLS NETWORKS --- p.34<br>Chapter 3.1 --- Existing Labelling Schemes and Their Features --- p.34<br>Chapter 3.1.1 --- Bit serial labelling --- p.35<br>Chapter 3.1.2 --- Subcarrier multiplexed (SCM) labelling --- p.36<br>Chapter 3.1.3 --- Orthogonally modulated labelling --- p.37<br>Chapter 3.2 --- The Proposed 00K Labelling Scheme and OLS System Architecture --- p.38<br>Chapter 3.3 --- All-Optical Label Swapping and Other Critical Issues --- p.39<br>Chapter 3.4 --- System demonstration --- p.40<br>Chapter 3.5 --- Summary --- p.45<br>Chapter 4 --- PERFORMANCE CHARACTERIZATION OF THE ASK/FSK AND ASK/DPSK ORTHOGONAL SIGNALS --- p.46<br>Chapter 4.1 --- Introduction and Formulation --- p.46<br>Chapter 4.2 --- Theoretical Analysis --- p.48<br>Chapter 4.2.1 --- Optical ASK performance in orthogonal signals --- p.48<br>Chapter 4.2.2 --- Optical FSK performance in ASK/FSK signals --- p.49<br>Chapter 4.2.3 --- Optical DPSK performance in ASK/DPSK signals --- p.51<br>Chapter 4.3 --- Analytical and Experimental Results --- p.55<br>Chapter 4.4 --- Conclusion --- p.57<br>Chapter 5 --- SUMMARY --- p.58<br>Chapter 5.1 --- Thesis Summary --- p.58<br>Chapter 5.2 --- Future Work --- p.59<br>LIST OF PUBLICATIONS --- p.61<br>REFERENCES --- p.62

碩士<br>國立暨南國際大學<br>電機工程學系<br>95<br>Power-Line network is the most common & deepest network system in our life. Its trace can be seen as long as there are people. Since there is the complete structure network beside us, we should use it, the huge resource, well, apply all kinds of communication mode structures to Power-Line network and develop the maximum benefit by the minimum cost. At present, the development of Power-Line digital signal process chip has already quite matured. To counter with the limits of laws & the demands of market orientation of different nations, the current mainstream is LM1893 (National Semiconductor), ST7536 (SGS Thomson Co.), and SSC-P300 (Intellon Co.), each R&D team develops separately digital signal process with the complete structure & individual features. Therefore, Power-Line digital signal process chip will not be talked in this article. This study focuses on the ‘Analogy Electric Circuit Block’ of Driving Output Circuit Power-Line Communication System. Its design & analysis are to use electric circuit design skill & auxiliary analysis of packaged software to reach low loss & low delay time in signal process and raise the reliability & transmission efficiency of data transmission. After executing the designed electric circuit of this study, the real measured loss value of driving output circuit is 24dB, and the real measured signal delay time is 1.25us, all conform to our designed specification. Finally, hope this study can make some contribution to Power Line Communication System.

Pun Siu Sun.<br>Thesis (M.Phil.)--Chinese University of Hong Kong, 2005.<br>Includes bibliographical references (leaves 55-58).<br>Abstract in English and Chinese.<br>ABSTRACT --- p.ii<br>摘要 --- p.iv<br>Chapter 1 --- BLACKGROUND AND INTRODUCTION --- p.1<br>Chapter 1.1 --- OPTICAL FREQUENCY SHIFT KEYING (FSK) --- p.1<br>Chapter 1.1.1 --- Basic concepts --- p.1<br>Chapter 1.1.2 --- Applications --- p.3<br>Chapter 1.2 --- MODULATION FORMATS --- p.6<br>Chapter 1.3 --- ORTHOGONAL MODULATION --- p.9<br>Chapter 1.4 --- THESIS ORGANIZATION --- p.11<br>Chapter 2 --- A NOVEL OPTICAL FREQUENCY SHIFT KEYING TRANSMITTER BASED ON POLARIZATION MODULATION --- p.12<br>Chapter 2.1 --- EXISTING OPTICAL FSK TRANSMITTER DESIGNS --- p.12<br>Chapter 2.1.1 --- Optical FSK transmitter based on complementary intensity modulation --- p.12<br>Chapter 2.1.2 --- Optical FSK transmitter based on direct modulation in a DFB laser --- p.13<br>Chapter 2.1.3 --- Optical FSK transmitter based on single side-band (SSB) modulation technique --- p.15<br>Chapter 2.1.4 --- Optical Continuous-Phase FSK (CPFSK) transmitter based on asymmetric Mach-Zehnder modulator --- p.17<br>Chapter 2.1.5 --- Optical FSK transmitter based on phase modulation --- p.18<br>Chapter 2.1.6 --- Summary --- p.20<br>Chapter 2.2 --- PROPOSED OPTICAL FSK TRANSMITTER BASED ON POLARIZATION MODULATION --- p.21<br>Chapter 2.3 --- EXPERIMENTAL DEMONSTARTION --- p.23<br>Chapter 2.4 --- SYSTEM PERFORMANCE --- p.25<br>Chapter 2.5 --- SUMMARY --- p.27<br>Chapter 3 --- OPTICAL RETURN-TO-ZERO FREQUENCY SHIFT KEYING (RZ-FSK) (RZ-FSK) --- p.28<br>Chapter 3.1 --- INTRODUCTION AND MOTIVATION --- p.28<br>Chapter 3.2 --- PREVIOUS NRZ vs. RZ COMPARISON --- p.30<br>Chapter 3.3 --- RZ-FSK TRANSMITTER DESIGN --- p.32<br>Chapter 3.4 --- PERFROMANCE COMPARISON --- p.33<br>Chapter 3.4.1 --- Back-to-back performance --- p.34<br>Chapter 3.4.2 --- Chromatic dispersion tolerance --- p.35<br>Chapter 3.4.3 --- Fiber nonlinearity tolerance --- p.38<br>Chapter 3.5 --- SUMMARY --- p.41<br>Chapter 4 --- A NOVEL OPTICAL TRANSMITTER FOR HIGH-SPEED DIFFERENTIAL PHASE SHIFT KEYING/INVERSE RETURN-TO-ZERO (DPSK/INV-RZ) ORTHOGONALLY MODULATED SIGNALS --- p.42<br>Chapter 4.1 --- INTRODUCTION --- p.42<br>Chapter 4.2 --- PREVIOUS SCHEME --- p.43<br>Chapter 4.3 --- PROPOSED TRANSMITTER DESIGN --- p.45<br>Chapter 4.4 --- EXPERIMENT AND RESULTS --- p.47<br>Chapter 4.5 --- CONCLUSION --- p.51<br>Chapter 5 --- SUMMARY --- p.52<br>Chapter 5.1 --- THESIS SUMMARY --- p.52<br>Chapter 5.2 --- FUTURE WORK --- p.53<br>LIST OF PUBLICATIONS --- p.54<br>REFERENCES --- p.55

碩士<br>國立成功大學<br>電機工程學系<br>106<br>This thesis proposes a dual-resonant mixed coupling coil (MCC) which have lateral and angular misalignment immunity, and can be applied in frequency shift keying wireless power and data transfer systems. By considering the duality property of electrical coupling and magnetic coupling, MCCs make the efficiency of wireless power transfer nearly insensitive to axial and angular misalignment. Comparing to MCC model in literatures, a more complete, sophisticated equivalent circuit demonstrates its dual-resonant characteristic and lateral and angular misalignment tolerable features. Also, the mixed coupled characteristics is mathematically analyzed, and an optimization flow of proposed MCC is suggested. Finally, the proposed MCC occupies 74×74 mm2. While MCC transfers energy with low resonant frequency, comparing to traditional printed spiral coils, S21 decline rate improves 26.4 % and 78.1 % while axially misaligned 60 mm and angularly misaligned 90˚, respectively. Furthermore, while proposed MCC transfers energy with high resonant frequency, S21 only drops 16.5 % with 60 mm lateral misalignment, and is totally flat within the whole ± 90˚ angular misalignment.

It is well known that multiple antennas at the transmitter and receiver are imperative for reliable and high data-rate communication over wireless channels. However, these systems essentially need multiple radio frequency (RF) chains owing to multiple antennas, and hence pose challenges for applications with limited form-factor. Antenna Selection (AS) techniques alleviate this problem by using only a subset of the total available antennas and hence require only a few RF chains compared to the number of antennas. These systems operate in a closed-loop scenario, where the information fed back from the receiver is used for the transmit antenna subset selection. In contrast to this, a novel open-loop technique known as spatial modulation (SM) was recently proposed that uses a single RF-chain at the transmitter and achieves a higher spectral efficiency compared to single-input and AS based systems. The work in the thesis mainly focuses on the following aspects of SM system: Study of Mutual Information in SM systems operating in open-loop and closed-loop scenarios: We study the achievable mutual information in the SM system operating with finite and Gaussian input alphabet, and compare the results with that of the SIMO and AS based systems. Reduced-complexity maximum-likelihood (ML) decoding algorithms for SM systems: We propose ML-optimal sphere decoders for SM systems with arbitrary number of transmit antennas. Furthermore, a reduced-complexity ML detector is also proposed whose computational complexity is lowest among the known existing detectors in the literature. Transmit diversity techniques for SM systems: The conventional SM system achieves a transmit diversity order of one. We propose a complex interleaved orthogonal design baaed SM scheme that achieves a transit diversity order of two, while offering symbol-by- symbol ML decodability. Transmit antenna subset selection algorithms for SM systems: The SM system is considered in the closed-loop scenario, where only a subset of the total number of transmit antennas is chosen based on the information fed back by the receiver. Specifically, the Euclidean distance and capacity optimized antenna selection algorithms are studied in comparison with the conventional AS based systems. SM system operating in dispersive channels: The SM system operating in a dispersive channel with the aid of zero-padding is studied. It is shown that the SM system achieves full receive-diversity and multipath-diversity with ML decoding, but offers a decoding complexity that is exponential in the number of multipaths. Furthermore, a reduced complexity linear receiver is proposed that achieves achieves full multipath as well as receive-diversity, while offering a decoding complexity order same as that of the SM system operating in a frequency-flat channel.

It is well known that multiple antennas at the transmitter and receiver are imperative for reliable and high data-rate communication over wireless channels. However, these systems essentially need multiple radio frequency (RF) chains owing to multiple antennas, and hence pose challenges for applications with limited form-factor. Antenna Selection (AS) techniques alleviate this problem by using only a subset of the total available antennas and hence require only a few RF chains compared to the number of antennas. These systems operate in a closed-loop scenario, where the information fed back from the receiver is used for the transmit antenna subset selection. In contrast to this, a novel open-loop technique known as spatial modulation (SM) was recently proposed that uses a single RF-chain at the transmitter and achieves a higher spectral efficiency compared to single-input and AS based systems. The work in the thesis mainly focuses on the following aspects of SM system: Study of Mutual Information in SM systems operating in open-loop and closed-loop scenarios: We study the achievable mutual information in the SM system operating with finite and Gaussian input alphabet, and compare the results with that of the SIMO and AS based systems. Reduced-complexity maximum-likelihood (ML) decoding algorithms for SM systems: We propose ML-optimal sphere decoders for SM systems with arbitrary number of transmit antennas. Furthermore, a reduced-complexity ML detector is also proposed whose computational complexity is lowest among the known existing detectors in the literature. Transmit diversity techniques for SM systems: The conventional SM system achieves a transmit diversity order of one. We propose a complex interleaved orthogonal design baaed SM scheme that achieves a transit diversity order of two, while offering symbol-by- symbol ML decodability. Transmit antenna subset selection algorithms for SM systems: The SM system is considered in the closed-loop scenario, where only a subset of the total number of transmit antennas is chosen based on the information fed back by the receiver. Specifically, the Euclidean distance and capacity optimized antenna selection algorithms are studied in comparison with the conventional AS based systems. SM system operating in dispersive channels: The SM system operating in a dispersive channel with the aid of zero-padding is studied. It is shown that the SM system achieves full receive-diversity and multipath-diversity with ML decoding, but offers a decoding complexity that is exponential in the number of multipaths. Furthermore, a reduced complexity linear receiver is proposed that achieves achieves full multipath as well as receive-diversity, while offering a decoding complexity order same as that of the SM system operating in a frequency-flat channel.