This dissertation presents a novel large signal modeling approach which can be used to accurately model CMOS transistors used in millimeter-wave CMOS power amplifiers. The large signal model presented in this work is classified as an empirical compact device model which incorporates temperature-dependency and device periphery scaling. These added features allow for efficient design of multi-stage CMOS power amplifiers by virtue of the process-scalability. Prior to the presentation of the details of the model development, background is given regarding the 90nm CMOS process, device test structures, de-embedding methods and device measurements, all of which are necessary preliminary steps for any device modeling methodology. Following discussion of model development, the design of multi-stage 60GHz Class AB CMOS power amplifiers using the developed model is shown, providing further model validation. The body of research concludes with an investigation into designing a CMOS power amplifier operating at frequencies close to the millimeter-wave range with a potentially higher-efficiency class of power amplifier operation. Specifically, a 24GHz 130nm CMOS Inverse Class F power amplifier is simulated using a modified version of the device model, fabricated and compared with simulations. This further demonstrates the robustness of this device modeling method.

<p>Rapporten är en jämförande studie av täckningsgrad och bandbredd i trådlösa nätverk av typ hot-spot med IEEE 802.11A/G respektive IEEE 802.11N Draft 2.0. Studien är gjord i tre olika scenarion på Kvarnholmen i Kalmar under april och maj månad 2008.</p>

The growth and expansion of modern society rely heavily upon well-functioning data communication over the internet. This phenomenon is seen at the company Net Insight where the need for transferring a large amount of data in the form of media over the internet in an effective manner is a high priority. At the moment most internet traffic in the modern world is done by the use of the internet protocol TCP (Transmission Control Protocol) instead of the simpler protocol UDP (User Datagram Protocol). Although TCP works in an excellent manner for most kinds of data communication it seems that this might not always be the case, so the use of UDP might be the better option in some occurrences. It is therefore of high interest at Net Insight to see how different types of wireless networks behave under different network circumstances when data is sent in different ways through the use of UDP. Thereby this report focuses on the measurement and analysis of how different wireless networks, specifically 4G, 5.0 GHz and 2.4 GHz WLAN networks, behaves when exposed to varied network environments where data is transmitted by the use of UDP in different ways. To perform a network-analysis data is collected, processed, and then analyzed. This network-analysis resulted in many conclusions regarding network behavior and performance for the different wireless networks.

[pt] A busca constante pela melhoria dos meios de comunicação em banda larga demandou o surgimento de novas tecnologias visando atender a real necessidade de seus usuários. O uso de mobilidade no acesso à internet banda larga como propõem os padrões WiMAX e LTE, impõe a necessidade de se estudar com mais profundidade os parâmetros que caracterizam um canal rádio móvel. Este trabalho objetiva apresentar os resultados experimentais que permitem caracterizar em banda estreita o comportamento do canal de radiopropagação num ambiente urbano. Como resultado das campanhas de medições, são identificados modelos do canal que possibilita ao projetista definir os melhores critérios para a implantação de uma rede móvel de acesso sem fio. Desta forma, são apresentadas duas campanhas de medições, operando nas frequências de 2,5 GHz e 3,5 GHz, destinadas para novos serviços móveis banda larga. / [en] The constant search for improvement of broadband communication systems requires new technologies to attend the increasing needs of the users. The use of mobility in broadband Internet access as proposed in WiMAX and LTE standards, imposes the need to further understand the parameters that characterize a channel mobile radio. This dissertation presents experimental results that allow characterizing the narrow band channel behavior of radio propagation in an urban environment. As a result of measurement campaigns, channel models are identified which allow the designer to define the best criteria to implement a mobile wireless network. The work presents results of two measurement campaigns, at the frequencies of 2.5 GHz and 3.5 GHz, designed for new mobile broadband services.

La bande de fréquence non-licensée autour de 60 GHz est une alternative prometteuse pour couvrir les besoins en bande passante des futurs systèmes de communication. L'utilisation de modulations complexes (comme OFDM ou 64-QAM) à ces fréquences permet d'atteindre, en utilisant une technologie CMOS standard, des débits de plusieurs gigabits par seconde sur quelques mètres voire quelques dizaines de mètres. Pour atteindre ces performances, la tête d'émission-réception RF (front-end RF) doit être dotée d'une référence de fréquence haute performance. Dans ce travail, une architecture originale est proposée pour générer cette référence de fréquence haute performance. Elle repose sur la multiplication de fréquence d'ordre élevé (plusieurs dizaines) d'un signal de référence basse fréquence (moins de quelques GHz), tout en recopiant les propriétés spectrales du signal basse fréquence. Cette multiplication est réalisée en combinant la production d'un signal multi-harmonique dont la puissance est concentrée autour de la fréquence à synthétiser. L'harmonique d'intérêt est ensuite extraite au moyen d'un filtrage. Ces deux étapes reposent sur l'utilisation d'oscillateurs dans des configurations spécifiques. Ce travail porte à la fois sur la mise en équation et l'étude du fonctionnement de ce système, et sur la conception de circuits dans des technologies CMOS avancées (CMOS 40 nm, BiCMOS 55 nm). Les mesures sur les circuits fabriqués permettent de valider la preuve de concept ainsi que de montrer des performances à l'état de l'art. L'étude du fonctionnement de ce système a conduit à la découverte d'une forme particulière de synchronisation des oscillateurs ainsi qu'à l'expression de solutions approchées de l'équation de Van der Pol dans deux cas pratiques particuliers. Les perspectives de ce travail sont notamment l'intégration de cette synthèse innovante dans un émetteur-récepteur complet. / The 60-GHz unlicensed band is a promising alternative to perform the high data rate required in the next generation of wireless communication systems. Complex modulations such as OFDM or 64-QAM allow reaching multi-gigabits per second throughput over up to several tens of meters in standard CMOS technologies. This performance rely on the use of high performance millimeter-wave frequency synthesizer in the RF front-end. In this work, an original architecture is proposed to generate this high performance millimeter-wave frequency synthesizer. It is based on a high order (several tens) multiplication of a low frequency reference (few GHz), that is capable of copying the low frequency reference spectral properties. This high order frequency multiplication is performed in two steps. Firstly, a multi-harmonic signal which power is located around the harmonic of interest is generated from the low frequency reference signal. Secondly, the harmonic of interest is filtered out from this multi-harmonic signal. Both steps rely on the specific use of oscillators. This work deals with the circuit design on advanced CMOS technologies (40 nm CMOS, 55 nm BiCMOS) for the proof of concept and on the theoretical study of this system. This novel technique is experimentally validated by measurements on the fabricated circuits and exhibit state-of-the-art performance. The analytical study of this high order frequency multiplication led to the discovery of a particular kind of synchronization in oscillators and to approximated solutions of the Van der Pol equation in two different practical cases. The perspectives of this work include the design of the low frequency reference and the integration of this frequency synthesizer in a complete RF front-end architecture.

[pt] O termo de ondas milimétricas refere-se à porção do espectro eletromagnético com frequências entre 30 e 300 GHz, correspondente a comprimentos de onda de 10 até 1 mm, respectivamente. As características das ondas milimétricas diferem das micro-ondas e das infravermelhas, e são estas diferenças que fazem com que um sistema de ondas milimétricas seja o candidato ideal para algumas aplicações. Nos anos passados, a falta e o alto custo de fontes, dispositivos, componentes e instrumentação adequada, para esta faixa de frequências, levaram a um progresso muito devagar nesta área, no entanto, as limitações dos sistemas infravermelhos e ópticos e a superlotação da região do micro-ondas do espectro ocasionaram um maior interesse em frequências milimétricas nos últimos anos. A quinta geração dos sistemas móveis deve estar pronta nos próximos anos, e muitas pesquisas estão se desenvolvendo nas faixas de 28 GHz, 38 GHz e 60 GHz. A faixa de 60 GHz, na qual as ondas têm uma maior atenuação comparada com as outras duas, oferece um maior espectro eletromagnético. Nesta faixa de frequência, as ondas se refletem muito e pode se aproveitar estas reflexões para uma melhor recepção sendo, por tanto, uma ótima opção para comunicação móvel de curta distância com altas taxas de transferência de dados. Para poder aproveitar a maior quantidade de multipercursos, a antena receptora deve ter uma largura de feixe grande. Assim, neste trabalho, duas antenas foram projetadas, construídas e, de alguma forma, testadas para uma frequência de 60 GHz, onde as larguras de feixe simuladas obtidas foram de 112 graus e 115 graus. / [en] The millimeter wave term refers to that portion of the electromagnetic spectrum with frequencies between 30 and 300 GHz corresponding to wavelengths of 1 to 10 mm. The characteristics of the millimeter wave differ from microwave and infrared, and these differences make a millimeter wave system, an ideal candidate for some applications. In the past the lack and the high cost of supplies, devices, components and instrumentation suitable for this frequency band caused very rambling progress in this area. However, the limitations of infrared optical systems and overcrowding of the microwave spectrum region led to a greater interest in the millimeter frequency in recent years and it is expected an increase in this interest. The fifth generation of mobile systems should be ready in the coming years, and many studies are developing in the 28 GHz, 38GHz and 60GHz bands. In the 60 GHz band, waves has a higher attenuation compared to the other two, but also offers greater electromagnetic spectrum, in this band, waves has a lot of reflection, then, scattering can be taken for better reception. So, this band is a great choice for short distance mobile communication with high data rates. To get the greatest amount of multipath, the receiving antenna must have a wide beam width. In this work, two antennas were designed, built and somewhat tested for a frequency of 60 GHz for mobile environment, where the beam widths obtained are 112 degrees and 115 degrees.

L'objectif de cette thèse est de réaliser un système radio-sur-fibre bidirectionnel fonctionnant dans la bande des fréquences millimétriques autour de 60 GHz. La solution proposée est basée sur l'utilisation d'une photodiode PIN en tant que mélangeur optoélectronique. Une étude théorique associée à une caractérisation non-linéaire et large bande de la photodiode a permis de modéliser le comportement mélangeur de la photodiode. Le modèle de photodiode obtenu a ensuite été utilisé pour optimiser les performances du mélangeur optoélectronique puis du système radio-sur-fibre complet. Des mesures expérimentales ont permis de vérifier la compatibilité du système proposé avec les spécifications du standard ECMA 387 proposé pour régir la création de réseaux locaux aux fréquences de 60 GHz, pour au moins les deux premiers débits proposés (394 Mb/s et 794 Mb/s). / The aim of this thesis is to develop a bidirectional millimeter-wave radio-over-fiber system. The proposed system is based on the use of a p-i-n photodiode as an optoelectronic mixer. A theoretical study coupled with a non-linear and wideband photodiode characterization allows modeling of the photodiode mixing process. Then, the developed photodiode model was used to optimize the optoelectronic mixer efficiency and finally, to optimize the complete radio-over-fiber system efficiency. Experimental measurement has been made to check the compliance of the developed system with the specifications of the ECMA 387 standard that is proposed for the use of the 60 GHz frequency band. Measurement complies with the standard for at least the first data rates (394 Mb/s and 794 Mb/s).

L’arrivée de la prochaine technologie 5G va permettre la connectivité des billions de terminaux mobiles et donc une énorme augmentation du trafic de données. A cet égard, les fournisseurs des services Cloud doivent posséder les infrastructures physiques capables de supporter cette explosion de trafic. Malheureusement, les architectures filaires conventionnelles des centres de données deviennent staturées et la congestion des équipements d’interconnexion est souvent atteinte. Dans cette thèse, nous explorons une approche récente qui consiste à augmenter le réseau filaire du centre de données avec l’infrastructure sans fil. En effet, nous exploitons une nouvelle technologie émergente, la technologie 60 GHz, qui assure un débit de l’ordre de 7 Gbits/s afin d’améliorer la QoS. Nous concevons une architecture hybride (filaire/sans fil) du réseau de centre de données basée sur : i) le modèle "Cisco’s Massively Scalable Data Center" (MSDC), et ii) le standard IEEE 802.11ad. Dans une telle architecture, les serveurs sont regroupés dans des racks, et sont interconnectés à travers un switch Ethernet, appelé top-of-rack (ToR) switch. Chaque ToR switch possède plusieurs antennes utilisées en parallèle sur différents canaux sans fil. L’objectif final consiste à minimiser la congestion du réseau filaire, en acheminant le maximum du trafic sur les canaux sans fil. Pour ce faire, cette thèse se focalise sur l’optimisation du routage et de l’allocation des canaux sans fil pour les communications inter-rack, au sein d’un centre de données hybride (HDCN). Ce problème étant NP-difficile, nous allons procéder en trois étapes. En premier lieu, on considère le cas des communications à un saut, où les racks sont placés dans le même rayon de transmission. Nous proposons un nouvel algorithme d’allocation des canaux sans fil dans les HDCN, qui permet d’acheminer le maximum des communications en sans-fil, tout en améliorant les performances réseau en termes de débit et délai. En second lieu, nous nous adressons au cas des communications à plusieurs sauts, où les racks ne sont pas dans le même rayon de transmission. Nous allons proposer une nouvelle approche optimale traitant conjointement le problème du routage et de l’allocation de canaux sans fils dans le HDCN, pour chaque communication, dans un mode online. En troisième étape, nous proposons un nouvel algorithme qui calcule conjointement le routage et l’allocation des canaux pour un ensemble des communications arrivant en mode batch (i.e., par lot). En utilisant le simulateur réseau QualNet, considérant toute la pile TCP/IP, les résultats obtenus montrent que nos propositions améliorent les performances comparées aux méthodes de l’état de l’art / The high proliferation of smart devices and online services allows billions of users to connect with network while deploying a vast range of applications. Particularly, with the advent of the future 5G technology, it is expected that a tremendous mobile and data traffic will be crossing Internet network. In this regard, Cloud service providers are urged to rethink their data center architectures in order to cope with this unprecedented traffic explosion. Unfortunately, the conventional wired infrastructures struggle to resist to such a traffic growth and become prone to serious congestion problems. Therefore, new innovative techniques are required. In this thesis, we investigate a recent promising approach that augments the wired Data Center Network (DCN) with wireless communications. Indeed, motivated by the feasibility of the new emerging 60 GHz technology, offering an impressive data rate (≈ 7 Gbps), we envision, a Hybrid (wireless/wired) DCN (HDCN) architecture. Our HDCN is based on i) Cisco’s Massively Scalable Data Center (MSDC) model and ii) IEEE 802.11ad standard. Servers in the HDCN are regrouped into racks, where each rack is equipped with a: i) Ethernet top-of-rack (ToR) switch and ii) set of wireless antennas. Our research aims to optimize the routing and the allocation of wireless resources for inter-rack communications in HDCN while enhancing network performance and minimizing congestion. The problem of routing and resource allocation in HDCN is NP-hard. To deal with this difficulty, we will tackle the problem into three stages. In the first stage, we consider only one-hop inter-rack communications in HDCN, where all communicating racks are in the same transmission range. We will propound a new wireless channel allocation approach in HDCN to hardness both wireless and wired interfaces for incoming flows while enhancing network throughput. In the second stage, we deal with the multi-hop communications in HDCN where communicating racks can not communicate in one single-hop wireless path. We propose a new approach to jointly route and allocate channels for each single communication flow, in an online way. Finally, in the third stage, we address the batched arrival of inter-rack communications to the HDCN so as to further optimize the usage of wireless and wired resources. For that end, we propose: i) a heuristic-based and ii) an approximate, solutions, to solve the joint batch routing and channel assignment. Based on extensive simulations conducted in QualNet simulator while considering the full protocol stack, the obtained results for both real workload and uniform traces, show that our proposals outperform the prominent related strategies

Rapporten är en jämförande studie av täckningsgrad och bandbredd i trådlösa nätverk av typ hot-spot med IEEE 802.11A/G respektive IEEE 802.11N Draft 2.0. Studien är gjord i tre olika scenarion på Kvarnholmen i Kalmar under april och maj månad 2008.

The aim of this diploma thesis is to study the possibilities and problems of low-profile antennas and subsequently to design a directional antenna with spherical reflector for millimeter wavelengths. The theoretical part deals with basic information about horn and reflector antennas, and about SIW technology. In addition, the thesis deals with the specific design and modeling of the antenna using CST Microwave Studio. The simulated design achieved a sufficient bandwidth to cover ISM (57 GHz to 64 GHz) with gain 13.6 dBi at 60 GHz frequency. On fabricated antenna, the antenna impedance ratios were worse and the target bandwidth was not reached. Antenna gain was 14.33 dBi at 60 GHz frequency.