Um novo circuito amplificador de 50 MHz - 1 GHz com alta linearidade para o padrão IEEE 802.22 “wireless regional area” (WRAN) é apresentado. Ele foi implementado sem nenhum indutor e oferece uma saída diferencial para ser utilizada como balun. Técnicas de cancelamento de ruído e aumento de linearidade foram usadas para melhorar a performace do amplificador de modo que eles pudessem ser otimizados separadamente. A linearidade foi melhorada utilizando transistores conectados como diodo. O amplificador foi implementado em um processo CMOS 130 nm, em uma área compacta de 136 m x 71 m. As simulações são apresentadas para esquemáticos pós-leiaute para duas classes diferentes de projeto: um visando a melhor linearidade e o outro a melhor Figura de Ruído (FR). Quando otimizado para melhor linearidade, os resultados de simulação atingem um ganho de tensão > 23.7 dB (ganho de potência > 19.1 dB), uma figura de ruído < 3.6 dB na banda inteira (com 2.4 dB min), um ponto de intersecção de terceira ordem (IIP3) > 3.3 dBm (7.6 dBm max) e um coeficiente de reflexão de entrada S11 < -16 dB. Quando otimizado para melhor figura de ruído, ele atinge um ganho de tensão > 24.7 dB (ganho de potência > 19.8 dB), uma FR < 2 dB na banda inteira, um IIP3 > -0.3 dBm e um S11 < -11 dB. Resultados de simulação Monte Carlo confirmam baixa sensibilidade à variabilidade de processo. Além disso, uma baixa sensibilidade com a temperatura na faixa de -55 até 125 C foi observada para Ganho, FR e S11. Consumo de potência é 17.6 mA sob fonte de alimentação de 1.2 V. / A new 50 MHz - 1 GHz low-noise amplifier circuit with high linearity for IEEE 802.22 wireless regional area network (WRAN) is presented. It was implemented without any inductor and offers a differential output for balun use. Noise cancelling and linearity boosting techniques were used to improve the amplifier performance in a way they can be separately optimized. Linearity was improved using diode-connected transistors. The amplifier was implemented in a 130 nm CMOS process in a compact 136 m x 71 m area. Simulations are presented for post-layout schematics for two classes of design: one for best linearity, another for best noise figure (NF). When optimized for best linearity, simulation results achieve a voltage gain > 23.7 dB (power gain > 19.1 dB), a NF < 3.6 dB over the entire band (with 2.4 dB min figure), an input third-order intercept point (IIP3) > 3.3 dBm (7.6 dBm max.) and an input power reflection coefficient S11 < -16 dB. When optimized for best NF, it achieves a voltage gain > 24.7 dB (power gain > 19.8 dB), a NF < 2 dB over the entire band, an IIP3 > -0.3 dBm and an S11 < -11 dB. Monte Carlo simulation results confirm low sensitivity to process variations. Also a low sensitivity to temperature within the range -55 to 125 C was observed for Gain, NF and S11. Power consumption is 17.6 mA under a 1.2 V supply.

Um novo circuito amplificador de 50 MHz - 1 GHz com alta linearidade para o padrão IEEE 802.22 “wireless regional area” (WRAN) é apresentado. Ele foi implementado sem nenhum indutor e oferece uma saída diferencial para ser utilizada como balun. Técnicas de cancelamento de ruído e aumento de linearidade foram usadas para melhorar a performace do amplificador de modo que eles pudessem ser otimizados separadamente. A linearidade foi melhorada utilizando transistores conectados como diodo. O amplificador foi implementado em um processo CMOS 130 nm, em uma área compacta de 136 m x 71 m. As simulações são apresentadas para esquemáticos pós-leiaute para duas classes diferentes de projeto: um visando a melhor linearidade e o outro a melhor Figura de Ruído (FR). Quando otimizado para melhor linearidade, os resultados de simulação atingem um ganho de tensão > 23.7 dB (ganho de potência > 19.1 dB), uma figura de ruído < 3.6 dB na banda inteira (com 2.4 dB min), um ponto de intersecção de terceira ordem (IIP3) > 3.3 dBm (7.6 dBm max) e um coeficiente de reflexão de entrada S11 < -16 dB. Quando otimizado para melhor figura de ruído, ele atinge um ganho de tensão > 24.7 dB (ganho de potência > 19.8 dB), uma FR < 2 dB na banda inteira, um IIP3 > -0.3 dBm e um S11 < -11 dB. Resultados de simulação Monte Carlo confirmam baixa sensibilidade à variabilidade de processo. Além disso, uma baixa sensibilidade com a temperatura na faixa de -55 até 125 C foi observada para Ganho, FR e S11. Consumo de potência é 17.6 mA sob fonte de alimentação de 1.2 V. / A new 50 MHz - 1 GHz low-noise amplifier circuit with high linearity for IEEE 802.22 wireless regional area network (WRAN) is presented. It was implemented without any inductor and offers a differential output for balun use. Noise cancelling and linearity boosting techniques were used to improve the amplifier performance in a way they can be separately optimized. Linearity was improved using diode-connected transistors. The amplifier was implemented in a 130 nm CMOS process in a compact 136 m x 71 m area. Simulations are presented for post-layout schematics for two classes of design: one for best linearity, another for best noise figure (NF). When optimized for best linearity, simulation results achieve a voltage gain > 23.7 dB (power gain > 19.1 dB), a NF < 3.6 dB over the entire band (with 2.4 dB min figure), an input third-order intercept point (IIP3) > 3.3 dBm (7.6 dBm max.) and an input power reflection coefficient S11 < -16 dB. When optimized for best NF, it achieves a voltage gain > 24.7 dB (power gain > 19.8 dB), a NF < 2 dB over the entire band, an IIP3 > -0.3 dBm and an S11 < -11 dB. Monte Carlo simulation results confirm low sensitivity to process variations. Also a low sensitivity to temperature within the range -55 to 125 C was observed for Gain, NF and S11. Power consumption is 17.6 mA under a 1.2 V supply.

Um novo circuito amplificador de 50 MHz - 1 GHz com alta linearidade para o padrão IEEE 802.22 “wireless regional area” (WRAN) é apresentado. Ele foi implementado sem nenhum indutor e oferece uma saída diferencial para ser utilizada como balun. Técnicas de cancelamento de ruído e aumento de linearidade foram usadas para melhorar a performace do amplificador de modo que eles pudessem ser otimizados separadamente. A linearidade foi melhorada utilizando transistores conectados como diodo. O amplificador foi implementado em um processo CMOS 130 nm, em uma área compacta de 136 m x 71 m. As simulações são apresentadas para esquemáticos pós-leiaute para duas classes diferentes de projeto: um visando a melhor linearidade e o outro a melhor Figura de Ruído (FR). Quando otimizado para melhor linearidade, os resultados de simulação atingem um ganho de tensão > 23.7 dB (ganho de potência > 19.1 dB), uma figura de ruído < 3.6 dB na banda inteira (com 2.4 dB min), um ponto de intersecção de terceira ordem (IIP3) > 3.3 dBm (7.6 dBm max) e um coeficiente de reflexão de entrada S11 < -16 dB. Quando otimizado para melhor figura de ruído, ele atinge um ganho de tensão > 24.7 dB (ganho de potência > 19.8 dB), uma FR < 2 dB na banda inteira, um IIP3 > -0.3 dBm e um S11 < -11 dB. Resultados de simulação Monte Carlo confirmam baixa sensibilidade à variabilidade de processo. Além disso, uma baixa sensibilidade com a temperatura na faixa de -55 até 125 C foi observada para Ganho, FR e S11. Consumo de potência é 17.6 mA sob fonte de alimentação de 1.2 V. / A new 50 MHz - 1 GHz low-noise amplifier circuit with high linearity for IEEE 802.22 wireless regional area network (WRAN) is presented. It was implemented without any inductor and offers a differential output for balun use. Noise cancelling and linearity boosting techniques were used to improve the amplifier performance in a way they can be separately optimized. Linearity was improved using diode-connected transistors. The amplifier was implemented in a 130 nm CMOS process in a compact 136 m x 71 m area. Simulations are presented for post-layout schematics for two classes of design: one for best linearity, another for best noise figure (NF). When optimized for best linearity, simulation results achieve a voltage gain > 23.7 dB (power gain > 19.1 dB), a NF < 3.6 dB over the entire band (with 2.4 dB min figure), an input third-order intercept point (IIP3) > 3.3 dBm (7.6 dBm max.) and an input power reflection coefficient S11 < -16 dB. When optimized for best NF, it achieves a voltage gain > 24.7 dB (power gain > 19.8 dB), a NF < 2 dB over the entire band, an IIP3 > -0.3 dBm and an S11 < -11 dB. Monte Carlo simulation results confirm low sensitivity to process variations. Also a low sensitivity to temperature within the range -55 to 125 C was observed for Gain, NF and S11. Power consumption is 17.6 mA under a 1.2 V supply.

This thesis project aims to develop an active Radio Frequency Identification tag (RFID) which uses an interesting method for positioning and ID detection. In this project, rather than classical ways of positioning methods such as triangulation or radio maps, infrared light and a camera with an infrared filter was used for the positioning. Tag identification detection is done by applying image analysis on camera images. When a specific part is wanted from the warehouse, this part is addressed through the active RFID system and the tag attached to that part starts to blink with the tag ID. A camera with an infrared filter above the goods in the ceiling finds the blinking infrared led, detects the tag’s position by image analysis, and confirms the ID with the requested ID number. A led transmitting visual light is used to ensure the tag also can be seen by the forklift driver in the warehouse environment when he is in close range of the part. First of all, related work and scientific papers were examined mostly from the IEEE database, which was instrumental in constructing this thesis project. Under the circumstances of low power consumption and the demands from the tag, additional possible components for an RFID tag such as an infrared led, a visual led, transistors for the LED amplifier stage and an LDO (Low-dropout) voltage regulator are chosen. Necessary technical calculations such as gain, power consumption are calculated. The RFID tag is built with these components, and transferred into the software environment .First the schematic is drawn and footprints created for the each component and the case styles are decided for transferring the circuit into the layout environment. For the radio circuit part which is used for the communication between the server and the tag, transmission lines of PCB demands are examined and the necessary calculations are made for impedance matching to prevent any disorder. After preparation of the PCB, gerber files are sent for the manufacturing process and the hardware part is completed. The components are mounted and the LED’s blinking time interval is set depending on the camera’s applicable frame speed, relevant tests for the ID detection and positioning (see fig.1). With optimisation of the time interval for recognition of the ID, an algorithm for the positioning of the RFID tag is developed and the related ID detection algorithm is developed for the real time applications by using a camera. As a result of this thesis project, instead of using complex systems for the positioning, such as triangulation or creating a radio map with multiple readers etc. a basic solution is produced as an alternative.  The efficiency of the system, the distance that allows the positioning and how applicable the system is are examined.

A uniplanar balun that transforms unbalanced coplanar waveguide (CPW) to balanced coplanar strip line (CPS) is characterised through simulation and measurement. By illustrating the effect of many of the critical design parameters, the operation of this balun is discussed and a set of design criteria is defined. The parameter study discusses the size and shape of the radial open, the type and length of the CPW taper and the thickness and type of the bond wires. Newly developed etched bond wires are implemented to provide better manufacturing repeatability and reliability. A complete balun testing procedure is developed and described, consisting of three separate tests. The balun is tested in the normal back-to-back configuration, as a terminated single balun, and the magnitude and phase imbalance is also determined by using a three-port test circuit connected to the balun. The advantages of implementing this full test procedure, and thus fully characterising the balun under test, are emphasised throughout. Results obtained by using this procedure show that the basic balun works well over the full operating band, except for the phase imbalance, which is usable but not optimal. A simple technique to correct the phase imbalance of the balun is introduced, and validated through measurements of the balun connected to the three-port test circuit. As a final validation the balun is connected as feed for an etched dipole antenna for which good impedance matching and pattern results are shown. AFRIKAANS : ’n Enkelvlak balon (BALans-na-ONbalans) wat van ongebalanseerde enkelvlak golfgeleier (CPW) na gebalanseerde enkelvlak strooklyn (CPS) transformeer, word gekarakteriseer deur simulasie en metings. Deur die effek van baie van die kritiese ontwerpsparameters te demonstreer, word die werking van die balon bespreek en ’n stel ontwerpskriteria opgestel. Die parameter studie bespreek die radiale ope struktuur se vorm en grote, die tipe en lengte van die CPW transformator and die dikte en tipe van die konneksie drade. Nuut ontwikkelde geëtste konneksie drade word geïmplementeer om beter vervaardigingsherhaalbaarheid en betroubaarheid te verseker. ’n Volledige balon toetsprosedure word ontwikkel en beskryf en bestaan uit drie aparte toetse. Die balon word getoets in die normale rug-aan-rug konfigurasie, as ’n enkel getermineerde balon en die grote asook fase van die wanbalans word bepaal deur die gebruik van ’n drie-poort toetsbaan wat aan die balon gekoppel word. Die voordele verbonde daaraan om hierdie volledige toetsprosedure toe te pas, en daardeur die balon volledig te karakteriseer, word deurlopend beklemtoon. Die resultate wat hierdie prosedure oplewer wys dat die basiese balon goed werk oor die volledige frekwensieband, behalwe vir die fase-wanbalans parameter, wat bruikbaar, maar nie ideaal is nie. ’n Eenvoudige tegniek om die fase-wanbalans van die balon te korrigeer word bekend gestel en getoets deur die drie-poort toetsbaan weer te gebruik. As ’n finale validasie word die balon aan ’n geëtste dipool gekoppel word, waarvan goeie impedansie aanpassings en patrone gewys word. Copyright / Dissertation (MEng)--University of Pretoria, 2010. / Electrical, Electronic and Computer Engineering / unrestricted

This work deals with the study of Yagi-Uda antennas, followed by analysis and design of planar antenna with wired reflector. The first part focused on the analysis of the antenna and parameters. Another part of the continuing investigation of the optimum parameters for a given antenna followed by a design in Wi-Fi 5 GHz band. The antenna is simulated in CST Microwave Studio. The final part devoted the results achieved

Spin torque oscillator (STO) technology has a unique blend of features, including but not limited to octave tunability, GHz operating frequency, and nanoscaled size, which makes it highly suitable for microwave and radar applications. This thesis studies the fundamentals of STOs, utilizes the state-of-art STO's advantages, and proposes two STO-based microwave systems targeting its microwave applications and measurement setup, respectively. First, based on an investigation of possible STO applications, the magnetic tunnel junction (MTJ) STO shows a great suitability for microwave oscillator in multi-standard multi-band radios. Yet, it also imposes a large challenge due to its low output power, which limits it from being used as a microwave oscillator. In this regard, different power enhancement approaches are investigated to achieve an MTJ STO-based microwave oscillator. The only possible approach is to use a dedicated CMOS wideband amplifier to boost the output power of the MTJ STO. The dedicated wideband amplifier, containing a novel Balun-LNA, an amplification stage and an output buffer, is proposed, analyzed, implemented, measured and used to achieve the MTJ STO-based microwave oscillator. The proposed amplifier core consumes 25.44 mW from a 1.2 V power supply and occupies an area of 0.16 mm2 in a 65 nm CMOS process. The measurement results show a S21 of 35 dB, maximum NF of 5 dB, bandwidth of 2 GHz - 7 GHz. This performance, as well as the measurement results of the proposed MTJ STO-based microwave oscillator, show that this microwave oscillator has a highly-tunable range and is able to drive a PLL. The second aspect of this thesis, firstly identifies the major difficulties in measuring the giant magnetoresistance (GMR) STO, and hence studying its dynamic properties. Thereafter, the system architecture of a reliable GMR STO measurement setup, which integrates the GMR STO with a dedicated CMOS high frequency IC to overcome these difficulties in precise characterization of GMR STOs, is proposed. An analysis of integration methods is given and the integration method based on wire bonding is evaluated and employed, as a first integration attempt of STO and CMOS technologies. Moreover, a dedicated high frequency CMOS IC, which is composed of a dedicated on-chip bias-tee, ESD diodes, input and output networks, and an amplification stage for amplifying the weak signal generated by the GMR STO, is proposed, analyzed, developed, implemented and measured. The proposed dedicated high frequency circuits for GMR STO consumes 14.3 mW from a 1.2 V power supply and takes a total area of 0.329 mm2 in a 65 nm CMOS process. The proposed on-chip bias-tee presents a maximum measured S12 of -20 dB and a current handling of about 25 mA. Additionally, the proposed dedicated IC gives a measured gain of 13 dB with a bandwidth of 12.5 GHz - 14.5 GHz. The first attempt to measure the (GMR STO+IC) pair presents no RF signal at the output. The possible cause and other identified issues are given. / <p>QC 20140114</p>

The aim of this study is to analysis, investigate and find out the solutions for the problems associated with the implementations of antennas RFID Reader and Tag for various applications. In particular, the efficiency of the RFID reader antenna and the detection range of the RFID tag antenna, subject to a small and compact antenna¿s design configuration have been studied. The present work has been addressed directly to reduce the cost, size and increase the detection range and communication reliability of the RFID framework antennas. Furthermore, the modelling concept of RFID passive tags mounted on various materials including the novel design of RFID reader antenna using Genetic Algorithm (GA) are considered and discussed to maintain reliable and efficient antenna radiation performances. The main benefit of applying GA is to provide fast, accurate and reliable solutions of antenna¿s structure. Therefore, the GA has been successfully employed to design examples: meander-line, two linear cross elements and compact Helical- Spiral antennas. In addition, a hybrid method to model the human body interaction with RFID tag antenna operating at 900MHz has been studied. The near field distribution and the radiation pattern together with the statistical distribution of the radiation efficiency and the absorbed power in terms of cumulative distribution functions for different orientation and location of RFID¿s tag antenna on the human body have been demonstrated. Several tag antennas wi th symmetrical and unsymmetrical structure configurations operating in the European UHF band 850-950 MHz have been fabricated and tested. . The measured and simulated results have been found to be in a good agreement with reasonable impedance matching to the typical input impedance of an RFID integrated circuit chip and nominal power gain and radiation patterns.

No / A compact-size asymmetrical linearly tapered slot antenna required for portable ultra-wideband (UWB) imaging systems is presented. The total antenna size is reduced compared with the conventional linearly tapered slot antenna by using a triangular slot on the left-hand side of the tapered-shaped radiator, whereas introducing a corrugated pattern of cuts on the right side. The antenna operates over a wide bandwidth extending from 3.1 to 10.6 GHz with a maximum gain of 8.5 dBi. Stable radiation patterns are observed across the operational bandwidth, with cross-polarization levels below 20 dB. The realized antenna structure occupies a volume of 35 x 36 x 0.8 mm3, and possesses the essential time domain fidelity needed for UWB imaging applications. (c) 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.

Actuellement, les fantassins de l'armée française sont équipés d'un système de radiocommunication quand ils sont en intervention sur le terrain. L'antenne utilisée pour émettre et recevoir les signaux radiofréquences (RF) est du type monopole appelée antenne fouet placée parallèlement au corps du fantassin au niveau de la clavicule gauche. Cependant, l'antenne fouet perturbe le champ de vision des fantassins surtout lorsqu'ils tournent leur tête vers la gauche. De plus, la position de l'antenne fouet gêne les fantassins gauchers lorsqu'ils sont en position de tir. Enfin, l'antenne fouet rajoute un poids supplémentaire. Il est évident alors que l'intégration de l'antenne dans les gilets militaires permet de mieux répondre aux besoins des fantassins notamment en termes d'ergonomie. Cependant une telle intégration doit aussi répondre aux besoins d'efficacité de rayonnement, de couverture spatiale et de protection du corps vis-à-vis du rayonnement de l'antenne. De plus les contraintes liées à la technologie de réalisation doivent être prises en compte. La thèse est focalisée sur la conception et la caractérisation d'antennes intégrées aux gilets militaires. Le travail de recherche s'est fait dans le cadre du projet collaboratif GIANTE, soutenu par le dispositif DGA-RAPID, associant les partenaires complémentaires : SAFRAN Sagem, le laboratoire LCIS et ARDEJE. Le travail inclue tous les développements relevant de la conception électromagnétique avec la prise en compte du corps humain et le suivi de la réalisation par impression numérique assurée par ARDEJE qui possède la technologique jet d'encre. Il concerne également la caractérisation RF (adaptation, bande passante, diagramme de rayonnement) des antennes avec un banc expérimental adapté et l'évaluation des performances globales des antennes en environnements fonctionnels (milieu dégagé, milieu urbain, forêt). / Nowadays, the infantrymen of French army are equipped with a radio communication system when they are in field action. The antenna used to transmit and receive Radiofrequency (RF) signals is a monopole antenna called as whip antenna. It is placed parallel to the infantryman's body at the left clavicle. However, the whip antenna disrupts the field of view of infantrymen particularly when they turn their head to the left. Moreover, the position of the whip antenna bothers the left-handed infantrymen when they are in fire position. Finally, the whip antenna adds an additional weight to the infantrymen. Thus, it is obvious that the integration of the antenna into the military jackets allows to better meet the needs of infantrymen particularly in terms of ergonomy. However such an integration must also meet the needs in terms of radiation efficiency, spatial coverage and protection of the body against the antenna radiation. Moreover, the constraints of realization technology must be taken into account. The thesis is focused on the design and characterization of integrated antennas into military jackets. The research work is performed within the collaborative project GIANTE, supported by the DGA-RAPID frameproject, associating complementary partners: SAFRAN Sagem, laboratory LCIS, and ARDEJE. The work includes all the electromagnetic studies required by the environmental constraints by taking account the human body. It also includes the follow-up of the realizations made by ARDEJE that masters inkjet printing technologies. The RF characterization (impedance matching, bandwidth, radiation pattern) of antennas with a suitable bench test and the evaluation of global performances of antennas in functional environments (environment free from obstructions, urban areas, forest) are also part of the thesis work.