Yes / New multi-standard wide band filters with compact sizes are designed for wireless communication devices. The proposed structures realize dual-wideband and quad-wideband characteristics by using a new skew-symmetrical coupled pair of asymmetric stepped impedance resonators, combined with other structures. The first and second dual-wideband filters realize fractional bandwidths (FBW) of 43.2%/31.9% at the central frequencies (CF) of 1.875/1.63 GHz, and second bandwidths of 580 MHz/1.75 GHz at CF of 5.52/4.46 GHz, respectively. The proposed quad-band filter realizes its first/second/third/fourth pass bands at CF 2.13/5.25/7.685/9.31 GHz with FBW of 46.0%/11.4%/4.6%and 5.4%, respectively. The wide pass bands are attributed to the mutual coupling of the modified ASIR resonators and their bandwidths are controllable by tuning relative parameters while the wide stop band performance is optimized by the novel interdigital cross coupled line structure and parallel uncoupled microstrip line structure. Moreover, the quad band is generated by introducing the novel defected rectangle structure. These multi-standard filters are simulated, fabricated and measured, and measured results agree well with both simulated results and theory predictions. The good in-band and out-of-band performances, the miniaturized sizes and simple structures of the proposed filters make them very promising for applications in future multi-standard wireless communication. / Horizon 2020 Framework Programme(European Union), Grant/Award Number:H2020-MSCA-ITN-2016 SECRET-722 424

Οι τεχνικές ασύρματης μετάδοσης Ultra Wide Band (UWB) είναι γνωστές εδώ και αρκετές δεκαετίες. Το ϐασικό χαρακτηριστικό των συγκεκριμένων συστη- μάτων είναι η εκπομπή και λήψη σήματος που εκτείνεται σε πολύ μεγάλο εύρος συχνοτήτων. Τα τελευταία χρόνια παρατηρείται διαρκώς αυξανόμενο ερευνητικό ενδιαφέρον γύρω από την περιοχή των τηλεπικοινωνιακών συ- στημάτων που χρησιμοποιούν UWB τεχνικές μετάδοσης, κυρίως λόγω της μεγάλης εφαρμοσιμότητάς της. Στις τηλεπικοινωνιακές εφαρμογές, η χρήση της τεχνικής UWB μπορεί να οδηγήσει σε αύξηση των ταχυτήτων ασύρματης μετάδοσης, λόγω της δυνατότητας εκπομπής μεγάλου αριθμού παλμών σε πολύ μικρό χρονικό διάστημα. Σε εφαρμογές εντοπισμού, το UWB μπορεί να ωθήσει προς την αύξηση της διακριτικής τους ικανότητας. Επίσης, κατάλ- ληλα UWB σήματα μπορούν να χρησιμοποιηθούν όπου υπάρχει ανάγκη για υψηλή διεισδυτικότητα μέσα από εμπόδια. Ο πιο απλός τρόπος μετάδοσης σήματος τέτοιου είδους είναι η εκπομ- πή εξαιρετικά σύντομων παλμών. Ο τρόπος με τον οποίο τα μεταδιδόμενα σύμβολα διαμορφώνουν αυτούς τους παλμούς ποικίλλει. Οι πρώτες UWB εφαρμογές χρησιμοποιούσαν σχεδόν αποκλειστικά την τεχνική Dιαμόρφωσης Θέσης Παλμού (Pulse Position Modulation PPM) γιατί η αντιστροφή πολύ σύντομων παλμών ήταν δύσκολο να υλοποιηθεί. Με αυτή την τεχνική, το κάθε μεταδιδόμενο σύμβολο καθορίζει τη ϑέση του παλμού στο πεδίο του χρόνου. Αργότερα, άρχισαν να χρησιμοποιούνται και τεχνικές Dιαμόρφωσης Πλάτους Παλμού (Pulse Amplitude Modulation PAM). Wστόσο, ένα μεγάλο πλεονέκτημα της μεθόδου PPM είναι οι μειωμένες απαιτήσεις της σε ισχύ, γιατί μεταδίδονται πολύ σύντομοι παλμοί ακολουθούμενοι από σχετικά με- γάλες περιόδους «σιωπής». Η ιδιότητα αυτή, καθιστά τη μέθοδο διαμόρφωσης PPM ιδιαίτερα ελκυστική σε εφαρμογές που απαιτούν χαμηλή κατανάλωση ισχύος. Σε αυτή την εργασία μελετούμε τη δομή ενός συστήματος μετάδοσης δε- δομένων Ultra Wide Band το οποίο χρησιμοποιεί τη μέθοδο διαμόρφωσης PPM. Η συμπεριφορά ενός τέτοιου συστήματος κατά τη μετάδοση μέσα από διάφορα κανάλια παρουσία ϑορύβου εξετάζεται μέσω εξομοίωσης. Είναι γνω- στό ότι τα συστήματα αυτά πλήττονται τόσο από το ϑόρυβο που εισάγεται λό- γω της μετάδοσης, διασυμβολική παρεμβολή, αλλά και παρεμβολή ανάμεσα στους πολλαπλούς χρήστες. Επίσης, οι περιορισμοί που ορίστηκαν στις ΗΠΑ για την μεταδιδόμενη ισχύ ανά συχνότητα των εμπορικών UWB εφαρμογών, οι οποίοι αναμένεται να υιοθετηθούν και στον υπόλοιπο κόσμο, αποτελούν ένα επιπλέον ϑέμα που επηρεάζει την επίτευξη υψηλών ϱυθμών μετάδοσης δεδομένων. Μια λύση είναι η χρήση τεχνικών ισοστάθμισης ή, ισοδύναμα, μεθόδων εκτίμησης του καναλιού που λειτουργούν στο δέκτη. Αν και οι κλασικές τεχνικές ισοστάθμισης ή εκτίμησης καναλιού μπορούν να εφαρμο- στούν με μικρές τροποποιήσεις και σε UWB σήματα διαμορφωμένα με PPM, ένα ϐασικό εμπόδιο είναι τόσο το μεγάλο πλήθος παραμέτρων που πρέπει να εκτιμηθούν (ένα τυπικό κανάλι σε εσωτερικό χώρο μπορεί να έχει ακόμη και πάνω από 150 συντελεστές), όσο και ο πολύ μεγάλος ϱυθμός δειγματοληψίας που απαιτείται. Επίσης, ϕαίνεται ότι μπορούν να αξιοποιηθούν τα ιδιαίτερα χαρακτηριστικά που εμφανίζει η εφαρμογή της διαμόρφωσης PPM σε UWB συστήματα, όπως είναι το ϕαινόμενο πολλαπλών μονοπατιών (multipath) σε συνδυασμό με την υψηλή διακριτικότητα (resolution) του σήματος UWB, ή ακόμη και η δυνατότητα μετάδοσης του ίδιου συμβόλου περισσότερες από μί- α ϕορές. Στα πλαίσια της εργασίας ϑα μελετηθούν και ϑα ενσωματωθούν στο σύστημα υπάρχουσες μέθοδοι εκτίμησης ή ισοστάθμισης καναλιού, οι οποί- ες αποτελούν προϊόν πρόσφατων προσπαθειών προς αυτή την κατεύθυνση. Θα μελετηθεί ο τρόπος με τον οποίο επιδρούν στην απόδοση του συστήμα- τος. Τέλος, ϑα εξεταστεί η δυνατότητα επέκτασης των μεθόδων εκτίμησης καναλιού με σκοπό τη ϐελτίωση της υπολογιστικής τους πολυπλοκότητας, μετατρέποντάς τους σε επαναληπτικούς/προσαρμοστικούς αλγορίθμους. / -

L’aéroacoustique est une filière de l'acoustique qui étudie la génération de bruit par un mouvement fluidique turbulent ou par les forces aérodynamiques qui interagissent avec les surfaces. Ce secteur en pleine croissance a attiré des intérêts récents en raison de l’évolution de la transportation aérienne, terrestre et spatiale. Les microphones avec une bande passante de plusieurs centaines de kHz et une plage dynamique couvrant de 40Pa à 4 kPa sont nécessaires pour les mesures aéroacoustiques. Dans cette thèse, deux microphones MEMS de type piézorésistif à base de silicium polycristallin (poly-Si) latéralement cristallisé par l’induction métallique (MILC) sont conçus et fabriqués en utilisant respectivement les techniques de microfabrication de surface et de volume. Ces microphones sont calibrés à l'aide d'une source d’onde de choc (N-wave) générée par une étincelle électrique. Pour l'échantillon fabriqué par le micro-usinage de surface, la sensibilité statique mesurée est 0.4μV/V/Pa, la sensibilité dynamique est 0.033μV/V/Pa et la plage fréquentielle couvre à partir de 100 kHz avec une fréquence du premier mode de résonance à 400kHz. Pour l'échantillon fabriqué par le micro-usinage de volume, la sensibilité statique mesurée est 0.28μV/V/Pa, la sensibilité dynamique est 0.33μV/V/Pa et la plage fréquentielle couvre à partir de 6 kHz avec une fréquence du premier mode de résonance à 715kHz. / Aero-acoustics, a branch of acoustics which studies noise generation via either turbulent fluid motion or aerodynamic forces interacting with surfaces, is a growing area and has received fresh emphasis due to advances in air, ground and space transportation. Microphones with a bandwidth of several hundreds of kHz and a dynamic range covering 40Pa to 4kPa are needed for aero-acoustic measurements. In this thesis, two metal-induced-lateral-crystallized (MILC) polycrystalline silicon (poly-Si) based piezoresistive type MEMS microphones are designed and fabricated using surface micromachining and bulk micromachining techniques, respectively. These microphones are calibrated using an electrical spark generated shockwave (N-wave) source. For the surface micromachined sample, the measured static sensitivity is 0.4μV/V/Pa, dynamic sensitivity is 0.033μV/V/Pa and the frequency range starts from 100kHz with a first mode resonant frequency of 400kHz. For the bulk micromachined sample, the measured static sensitivity is 0.28μV/V/Pa, dynamic sensitivity is 0.33μV/V/Pa and the frequency range starts from 6kHz with a first mode resonant frequency of 715kHz.

Ultra-wideband (UWB) communication has been the subject of extensive research in recent years due to its unique capabilities and potential applications, particularly in short-range multiple access wireless communications. However, many important aspects of UWB-based communication systems have not yet been thoroughly investigated. The propagation of UWB signals inside very small enclosed environments is one of the important issues with significant impacts on the future direction, scope, and generally the extent of the success of UWB technology. The objective of this thesis is to obtain a more thorough and comprehensive understanding of ultra-small UWB channels for communication applications and design issues for enhancing the data rate of UWB systems. This works supports the postulation of a high capacity UWB wireless interconnect scheme for communicating devices within conducting enclosures – a wireless “backplane”. This thesis proposes the use of an Ultra-Wide Bandwidth (UWB) ultra-small scale wireless interconnect scheme for use within electrically small enclosures. Such ultra-small environments (size ≤ 10 wavelengths) are topologically much more complex, being more cluttered, than typical indoor environments (size ≥ 10 wavelengths). The concept is presented through two different scenarios. Firstly, a PC Tower case is presented as a model environment and the work seeks to present the optimum channel performance, where EMI issues are discussed and problem avoidance proposed. Secondly, in order to extrapolate the different results from the study inside the PC, an investigation is carried out using an Aluminium tower case as a more generic model environment. The analysis is based on the behaviour of box modes within a conducting resonator enclosure and the effective communications bandwidth for UWB systems for different sizes and components within. From these general considerations the research presents theoretical and experimental results from which are derived the communications metrics measured within enclosures. Simulations of the different scenarios are performed using different techniques such as ray tracing and a full wave model, based on CST Microstripes. Empirical data is recorded using a vector network analyser (VNA)-based wideband channel sounding system where channel measurements are carried out in every scenario regarding different aspects such as frequency response and time domain analysis, evaluation of the channel capacity, power delay study and the nature of the environment.

The expanding growth of mobile products and services has led to various wireless communication standards that employ different spectrum bands and protocols to provide data, voice or video communication services. Software deffned radio and cognitive radio are emerging techniques that can dynamically integrate various standards to provide seamless global coverage, including global roaming across geographical regions, and interfacing with different wireless networks. In software deffned radio and cognitive radio, one of the most critical RF blocks that need to exhibit frequency agility is the phase lock loop (PLL) frequency synthesizer. In order to access various standards, the frequency synthesizer needs to have wide frequency tuning range, fast tuning speed, and low phase noise and frequency spur. The traditional analog charge pump frequency synthesizer circuit design is becoming diffcult due to the continuous down-scalings of transistor feature size and power supply voltage. The goal of this project was to develop an all digital phase locked loop (ADPLL) as the alternative solution technique in RF transceivers by taking advantage of digital circuitry's characteristic features of good scalability, robustness against process variation and high noise margin. The targeted frequency bands for our ADPLL design included 880MHz-960MHz, 1.92GHz-2.17GHz, 2.3GHz-2.7GHz, 3.3GHz-3.8GHz and 5.15GHz-5.85GHz that are used by wireless communication standards such as GSM, UMTS, bluetooth, WiMAX and Wi-Fi etc. This project started with the system level model development for characterizing ADPLL phase noise, fractional spur and locking speed. Then an on-chip jitter detector and parameter adapter was designed for ADPLL to perform self-tuning and self-calibration to accomplish high frequency purity and fast frequency locking in each frequency band. A novel wide band DCO is presented for multi-band wireless application. The proposed wide band adaptive ADPLL was implemented in the IBM 0.13µm CMOS technology. The phase noise performance, the frequency locking speed as well as the tuning range of the digitally controlled oscillator was assessed and agrees well with the theoretical analysis.

[pt] Esta dissertação tem como objetivo a utilização de modelos de regressão linear para a taxa de penetração de banda larga, baseados nas variáveis desemprego, PIB per capita, grau de competividade do mercado e diversidade tecnológica, utilizando uma análise dos modelos em diferentes países, com ênfase no Brasil, onde, nos últimos anos, tem sido analisadas diferentes alternativas para alcançar os objetivos do Plano Nacional de Banda Larga. A aplicação da metodologia apresentará a relação destas variáveis para os países com índices de adoção de banda larga ainda baixos, onde o Brasil está incluído, mas também apresenta a análise para países mais maduros neste índice. Estas análises poderão auxiliar na tomada de decisão das políticas públicas adequadas para o Brasil, buscando a aproximação dos países desenvolvidos neste setor. / [en] This thesis has as objective the developing of a model to estimate the broadband density penetration based on the unemployment rate, Gross Domestic Product per capita, market share and technological diversity. In addition of a global analysis, the thesis is focused in the Brazilian scenario, which is in a process of decision in which government policies to achieve the results expected by the National Broadband Plan. The methodoly will present the relation between these variables for the countries with lower broadband indexes, where Brazil is included, and the analysis for the countries with better indexes. These analyses can help Brazilian government in which policies should help Brazil to achieve results closer than the more mature countries in this sector.

<p>Today the frequency spectrum is full of wireless standards. The most common technique being used is the frequency modulation. To take advantage of this and the technology improvement a new wireless communication standard is being developed. This standard is using a low power impulse modulation method, allowing it to overlap with other standards. The proposed standard called IEEE802.15.3a is applied at an Ultra Wide Band and has potential to be used both in interchip and intrasystem communication, since it allows a very high data density. </p><p>In this thesis the analog to digital converter is designed, which is one part of a communication system. Although the signal bandwidth is very wide the converter is designed as a Sigma-Delta modulator, which is most suitable for low-speed applications. Its main advantages over high-speed converters are less area and less power consumption. The goal of this project is to investigate if the CMOS090 process technology will be sufficient for reaching a signal-to-noise ratio, SNR, of 30 dB in a signal band of 264 MHz. </p><p>The main limiting factor during the design of the modulator is the excess feedback delay. This delay degrades the SNR and can even make the system unstable. At a feedback delay of 83 ps and a sampling frequency of 6.336 GHz, the maximum SNR achieved was 27 dB. At this high frequency the modulator is close to instability. Hence, to ensure stability a maximum sampling frequency of 4.224 GHz is chosen, achieving a SNR of 19 dB. </p><p>The effect of the feedback delay can be reduced either by using a different structure or by using compensation methods, either of them would probably allow a SNR above 30 dB.</p>

<p>The waveform of a radar signal affects the resolution in velocity and distance. The ambiguity function is used as an aid for analysing narrow band radar signals simultaneously in time and frequency. An analysing tool for wide band radar signals is missing.</p><p>This thesis describes a generalised ambiguity function to be utilised for study of wide band signals. Waveforms are further synthesised with help of the developed analysing tool. The aim is to start with a certain ambiguity function and find a waveform that reproduces the same ambiguity function.</p><p>Mathematical formulas are presented and implemented in Matlab to produce the wide band ambiguity function. Functions for developing waveforms by synthesis is also implemented.</p><p>It turns out that the Hermitian functions used as base functions do not preserve the orthogonality when implemented as wide band signals. The synthesis is not fully successful. Therefore an alternative method with numerical optimisation is used in an attempt to find an optimal waveform.</p>

<p>Basic properties and new design principles of ultra wideband Vivaldi antennas are presentedand discussed in this paper. The focus will be on the modeling of Vivaldi antenna design curves, by which it is constructed; its simulation results, realization and the measurements.</p><p>According to the aim of this research the discussion starts with the review of the previous researches done for Vivaldi antennas. Introductory part of the report also contains the problem description for the current project and the classification of the goals to be achieved. As a theoretical review, the discussion initiates with the definitions anddescription of basic parameters of the antennas and covers a short presentation of UWBpulse-based radar system. The attention will be focused on UWB signals behavior and characterization, their propagation principles and basic troubles stands nowadays. As anapplication the wall penetrating Radar systems will be considered. The major part of thereport holds on the investigation of the design principles of Vivaldi Antenna andoptimization of the key parameters for achieving the best performance for radar. Theending part of the report shows the simulations and measurement results and theircomparisons following with conclusions/discussions.</p><p>The report will be supportive for the antenna designers, who work for UWB systems andparticularly for Vivaldi antennas, as long as there are showing up detailed descriptions ofVivaldi antenna characteristics depending on its shape and substrate properties. The modelfor designing Vivaldi antennas, given in this project, can successfully be applied for almostall the cases used in practice nowadays.</p>

The objective of this research is to demonstrate the feasibility of the implementation of wideband RF CMOS PLLs with high spectral purity using deep sub-micron technologies. To achieve wide frequency coverage, this dissertation proposed a 45-nm SOI-CMOS RF PLL with a wide frequency range to support multiple standards. The PLL has small parasitic capacitance with the help of a SOI technology, increasing the frequency tuning range of a capacitor bank. A designed and fabricated chip demonstrates the PLL supporting almost all cellular standards with a single PLL. This dissertation also proposed a third order sample-hold loop filter with two MOS switches for high spectral purity. Sample-hold operation improves in-band and out-of-band phase noise performance simultaneously in RF PLLs. By controlling the size of the MOS switches and control time, the nonideal effects of the MOS switches are minimized. The sample-hold loop filter is implemented within a 45-nm RF PLL and the performance is evaluated. Thus, this research provides a solution for wideband CMOS frequency synthesizers for multi-band, multi-mode, and multiple-standard applications in deep sub-micron technologies.