The objective of this thesis is to study the demodulation of narrowband radio frequency signals by aliasing sampling in order to reduce the sampling rate. The spectrum can be recreated at the lower frequency position by aliasing sampling. However, if the sampling rate is deviated from the desired one, error will occur. The sensitivity to the frequency error of aliasing sampling is studied. One main reason of the deviation of the sampling rate is the frequency drifting of the local oscillator. Being able to compensate the oscillator drifting errors inexpensively, automatic frequency control (AFC) loops are important at receivers. Two major digital AFC algorithms are studied. One is the Phase method AFC, and the other is the Magnitude method AFC. Study indicates that both methods perform almost equally well. One adaptive AFC algorithm is also proposed. The scheme of the adaptive AFC algorithm is to use Upper-bound and Lower-bound techniques to squeeze the frequency errors. It is shown that the adaptive AFC algorithm can achieve up to 20 dB average signal-to-noise power ratio over the Magnitude method AFC under a noisy environment.

Contactless cards are everywhere nowadays due to their ease to use and low price to produce. In addition, their reliability is excellent. That is why they are used in systems where security is essential within a low price. To develop the associated systems (cards, readers, terminals), efficient tools are needed. These tools can be a spy analyzing any communication or an emulator that can act and answer exactly as a real contactless card. The objective of this thesis was to develop a contactless card emulator on a product that is currently only spying, the NomadLAB of KEOLABS. The emulator feature is based on a discontinued product, the ProxiCARD, and it has for main objective to be compliant with the ISO 14443 standard. Through the analysis of its architecture and its current performance, I have developed a complete system that can be integrated into the ecosystem of the KEOLABS products. The features I developed take place into the source code of the NomadLAB, at the level of its ARM microcontroller in language C, and in its FPGA in language VHDL. The ARM is here to handle all the smart part of the transmission, while the FPGA to handle the coding and decoding process. In addition, I developed an antenna able to on one hand receive the signal from a reader and on the other hand to reply to it by modulating the magnetic field. I also developed and added my controls to the current computer software. Finally, I have written a lot of testing to make sure that this new system is reliable. The NomadLAB is now able to emulate a contactless card complying with ISO14443 standard, while keeping its spy features, and its control through a computer.

The design of the RF over fiber signal transport system for the ALPACA receiver is described, with particular attention to the strict noise requirements as well as dynamic range considerations. Also discussed are analytical tools for analyzing dynamic range in the context of RFI-rich radio astronomy observational settings, including formulas for maximum interference to noise ratios and a simulation framework for predicting distortion levels. Phase and gain stability measurements of the signal transport system are presented, including the effects of the multi-strand armored fiber optic cable. The resulting system meets design requirements, with equivalent noise temperature below 900 K in 90° F ambient air, resulting in less than 1 K contribution to the system noise temperature. Typical gain is 31-37 dB, and gain differences between channels are stable within 0.25 dB in 90° F conditions. Phase drift between channels due to electronics remains below 1° at room temperature, and below 1.3° in a warm environment. The fiber optic cable is predicted to cause phase changes between channels of no more than 1.3° per °C. Typical spurious free dynamic range is 99 dB·Hz^(⅔), and distortion levels for normal RFI conditions at Arecibo are expected to be 28 dB below the system noise floor.

The recent increased focus on patient safety in hospitals has yielded a flood of new technologies and tools seeking to improve the quality of patient care at the point of care. Hospitals are complex institutions by nature, and are constantly challenged to improve the quality of healthcare delivered to patients while trying to reduce the rate of medical errors and improve patient safety. Here a simple mistake such as patient misidentification, specimen misidentification, wrong medication, or wrong blood transfusion can cause the loss of a patient’s life. Misidentification of patients is a common problem that many hospitals face on the daily basis. Patient misidentification is one of the leading causes of medical errors and medical malpractice in hospitals and it has been recognised as a serious risk to patient safety. Recent studies have shown that an increasing number of medical errors are primarily caused by adverse drug events which are caused directly or indirectly by incorrect patient identification. In recognition of the increasing threat to patient safety, it is important for hospitals to prevent these medical errors from happening by adopting a suitable patient identification system that can improve upon current safety procedures. The focus of this master’s thesis is the design, implementation, and evaluation of a handheld-based patient identification system that uses radio frequency identification (RFID) and IEEE 802.11b wireless local area networks to identify patients. In this solution, each patient is given a RFID wristband which contains demographic information (patient ID number, ward number, hospital code, etc.) of the patient. A handheld device equipped with IEEE 802.11b wireless local area network connectivity and a RFID reader is then used by the medical staff to read the patient’s wristband, identify the patient, and access the relevant records of this patient. This work was carried out at the Department of Medical Physics and Bioengineering at the University College Hospital Galway (UCHG), Ireland and the National University of Ireland, Galway. / Ökande de nya fokuserar på patientsäkerhet i sjukhus har givit en översvämning av nya teknologier och bearbetar sökande att förbättra det kvalitets av patient omsorg på peka av omsorg. Sjukhus är komplexa institutions vid naturen och utmanas ständig för att förbättra det kvalitets av sjukvården som levereras till prövas patient för att förminska klassa av medicinska fel och för att förbättra patient säkerhet. Här kan ett enkelt fel liksom patient misidentification, specimenmisidentification, fel läkarbehandling eller fel blodtransfusion orsaka förlusten av ett liv för patient. Misidentification av patient är ett allmänningproblem som många sjukhus vänder mot daglig. Patient misidentification är en av leda orsakar av medicinska fel, och den medicinska malpracticen i sjukhus och den har känts igen som ett allvarligt riskerar till patient säkerhet. Nya studies har visat att ett ökande numrerar av medicinska fel orsakas i första hand av motsatt droghändelser vilka orsakas direkt eller indirekt av oriktigt patient ID. I recognition av den ökande hot till patientsäkerhet är det viktigt att sjukhus förhindrar dessa medicinska fel från att hända, genom att adoptera ett passande patient ID system som kan förbttra på säkerhetsrutin. Fokusera av denna avhandling är designen, genomförande, och utvärderingen av ett patient IDsystem, som använder radiofrekvensidentifiering (RFID) och radion 802.11b, knyter kontakt för att identifiera patient. I denna lösning ges varje patient ett RFID-armband som innehåller demografikinformation (den patient personnumer, avdelning kod, sjukhuset kod, osv.) av patient. En handdator, som utrustas med trådlös IEEE 802.11b och en RFIDs ändare/mottagare, används därefter av den medicinska personal för att läsa armbandet för patient och för att identifiera patient. Detta arbete bars ut på avdelningen av medicinskfysik och bioteknik på Universitetssjukhuset Galway (UCHG), Irland och den Nationella Universitet av Irland, Galway.

We propose an original analog method to perform instantaneous and quantitative spectral analysis of microwave signals. An ensemble of nitrogen-vacancy (NV) centers held in a diamond plate is pumped by a 532 nm laser. Its photoluminescence is imaged through an optical microscope and monitored by a digital camera. An incoming microwave signal is converted into a microwave field in the area of the NV centers by a loop shaped antenna. The resonances induced by the magnetic component of that field are detected through a decrease of the NV centers photoluminescence. A magnetic field gradient induces a Zeeman shift of the resonances and transforms the frequency information into spatial information, which allows for the simultaneous analysis of the microwave signal in the entire frequency bandwidth of the device. The time dependent spectral analysis of an amplitude modulated microwave signal is demonstrated over a bandwidth of 600 MHz, associated to a frequency resolution of 7MHz , and a refresh rate of 4 ms. With such integration time, a field of a few hundreds of lW can be detected. Since the optical properties of NV centers can be maintained even in high magnetic field, we estimate that an optimized device could allow frequency analysis in a range of 30 GHz, only limited by the amplitude of the magnetic field gradient. In addition, an increase of the NV centers quantity could lead both to an increase of the microwave sensitivity and to a decrease of the minimum refresh rate down to a few ls.

The purpose of this paper is to achieve wireless power transfer inside a resonating cavity, and thereby apply this to charge batteries. The idea is to convert radio frequency waves into direct current, which can charge the batteries. This was done by creating an LC-antenna, which in turn was connected to a rectifier. A data logger was also built, this to be able to read and log the power within the cavity to examine its power distribution. Because of COVID-19 restrictions, access to laboratory and equipment was limited. Due to this, smaller experiments where performed to make sure that all parts worked as intended before trying to perform tests inside the cavity resonator. The results were varied, some favorable, some not. However, all experiments gave insight and further understanding on the issue. The cavity operations had varied results. The data logger was able to pick up, at most, 7.6 % of the power output by the function generator. However, some problems arose with the rectifier which resulted in it not working for higher frequencies. Though, it was capable of rectifying RF signals at lower frequencies from a function generator, which was used to charge a battery. Consequently, there was no charging of batteries inside the cavity. However, three dimensional wireless power transfer was achieved. With some improvements to the current designs, the main goal could be accomplished

The state-of-the-art commercially available radio-frequency identification (RFID) transponders are usually composed of an antenna and an application specific integrated circuit chip, which still makes them very costly compared to the well-established barcode technology. Therefore, a novel low-cost RFID system solution based on passive chipless RFID transponders manufactured using conductive strips on flexible substrates is proposed in this work. The chipless RFID transponders follow a specific structure design, which aim is to modify the shape of the impinged electromagnetic wave to embed anidentification code in it and then backscatter the encoded signal to the reader. This dissertation comprises a multidisciplinary research encompassing the design of low-cost chipless RFID transponders with a novel frequency coding technique, unlike usually disregarded in literature, this approach considers the communication channel effects and assigns a unique frequency response to each transponder. Hence, the identification codes are different enough, to reduce the detection error and improve their automatic recognition by the reader while working under normal conditions. The chipless RFID transponders are manufactured using different materials and state-of-the-art mass production fabrication processes, like printed electronics. Moreover, two different reader front-ends working in the ultra-wideband (UWB) frequency range are used to interrogate the chipless RFID transponders. The first one is built using high-performance off-theshelf components following the stepped frequency modulation (SFM) radar principle, and the second one is a commercially available impulse radio (IR) radar. Finally, the two readers are programmed with algorithms based on the conventional minimum distance and maximum likelihood detection techniques, considering the whole transponder radio frequency (RF) response, instead of following the commonly used approach of focusing on specific parts of the spectrum to detect dips or peaks. The programmed readers automatically identify when a chipless RFID transponder is placed within their interrogation zones and proceed to the successful recognition of its embedded identification code. Accomplishing in this way, two novel fully automatic SFM- and IRRFID readers for chipless transponders. The SFM-RFID system is capable to successfully decode up to eight different chipless RFID transponders placed sequentially at a maximum reading range of 36 cm. The IR-RFID system up to four sequentially and two simultaneously placed different chipless RFID transponders within a 50 cm range.:Acknowledgments Abstract Kurzfassung Table of Contents Index of Figures Index of Tables Index of Abbreviations Index of Symbols 1 Introduction 1.1 Motivation 1.2 Scope of Application 1.3 Objectives and Structure Fundamentals of the RFID Technology 2.1 Automatic Identification Systems Background 2.1.1 Barcode Technology 2.1.2 Optical Character Recognition 2.1.3 Biometric Procedures 2.1.4 Smart Cards 2.1.5 RFID Systems 2.2 RFID System Principle 2.2.1 RFID Features 2.3 RFID with Chipless Transponders 2.3.1 Time Domain Encoding 2.3.2 Frequency Domain Encoding 2.4 Summary Manufacturing Technologies 3.1 Organic and Printed Electronics 3.1.1 Substrates 3.1.2 Organic Inks 3.1.3 Screen Printing 3.1.4 Flexography 3.2 The Printing Process 3.3 A Fabrication Alternative with Aluminum or Copper Strips 3.4 Fabrication Technologies for Chipless RFID Transponders 3.5 Summary UWB Chipless RFID Transponder Design 4.1 Scattering Theory 4.1.1 Radar Cross-Section Definition 4.1.2 Radar Absorbing Material’s Principle 4.1.3 Dielectric Multilayers Wave Matrix Analysis 4.1.4 Frequency Selective Surfaces 4.2 Double-Dipoles UWB Chipless RFID Transponder 4.2.1 An Infinite Double-Dipole Array 4.2.2 Double-Dipoles UWB Chipless Transponder Design 4.2.3 Prototype Fabrication 4.3 UWB Chipless RFID Transponder with Concentric Circles 4.3.1 Concentric Circles UWB Chipless Transponder 4.3.2 Concentric Rings UWB Chipless RFID Transponder 4.4 Concentric Octagons UWB Chipless Transponders 4.4.1 Concentric Octagons UWB Chipless Transponder Design 1 4.4.2 Concentric Octagons UWB Chipless Transponder Design 2 4.5 Summary 5. RFID Readers for Chipless Transponders 5.1 Background 5.1.1 The Radar Range Equation 5.1.2 Range Resolution 5.1.3 Frequency Band Selection 5.2 Frequency Domain Reader Test System 5.2.1 Stepped Frequency Waveforms 5.2.2 Reader Architecture 5.2.3 Test System Results 5.3 Time Domain Reader 5.3.1 Novelda Radar 5.3.2 Test System Results 5.4 Summary Detection of UWB Chipless RFID Transponders 6.1 Background 6.2 The Communication Channel 6.2.1 AWGN Channel Modeling and Detection 6.2.2 Free-Space Path Loss Modeling and Normalization 6.3 Detection and Decoding of Chipless RFID Transponders 6.3.1 Minimum Distance Detector 6.3.2 Maximum Likelihood Detector 6.3.3 Correlator Detector 6.3.4 Test Results 6.4 Simultaneous Detection of Multiple UWB Chipless Transponders 6.5 Summary System Implementation 7.1 SFM-UWB RFID System with CR-Chipless Transponders 7.2 IR-UWB RFID System with COD1-Chipless Transponders 7.3 Summary Conclusion and Outlook References Publications Appendix A RCS Calculation Measurement Setups Appendix B Resistance and Skin Depth Calculation Appendix C List of Videos Test Videos Consortium Videos Curriculum Vitae

La multiplication du nombre de cœurs de calcul présents sur une même puce va depair avec une augmentation des besoins en communication. De plus, la variété des applications s’exécutant sur la puce provoque une hétérogénéité spatiale et temporelle des communications. C’est pour répondre à ces problématiques que nous pré-sentons dans ce manuscrit un réseau d’interconnexion sur puce dynamiquement reconfigurable utilisant la Radio Fréquence (RF). L’utilisation de la RF permet de disposer d’une bande passante plus importante tout en minimisant la latence. La possibilité de reconfigurer dynamiquement le réseau permet d’adapter cette puce many-cœur à la variabilité des applications et des communications. Nous présentons les raisons du choix de la RF par rapport aux autres nouvelles technologies du domaine que sont l’optique et la 3D, l’architecture détaillée de ce réseau et d’une puce le mettant en œuvre ainsi que l’évaluation de sa faisabilité et de ses performances. Durant la phase d’évaluation nous avons pu montrer que pour un Chip Multiprocessor (CMP) de 1 024 tuiles, notre solution permettait un gain en performance de 13 %. Un des avantages de ce réseau d’interconnexion RF est la possibilité de faire du broadcast sans surcoût par rapport aux communications point-à-point,ouvrant ainsi de nouvelles perspectives en termes de gestion de la cohérence mémoire notamment. / The growing number of cores in a single chip goes along with an increase in com-munications. The variety of applications running on the chip causes spatial andtemporal heterogeneity of communications. To address these issues, we presentin this thesis a dynamically reconfigurable interconnect based on Radio Frequency(RF) for intra chip communications. The use of RF allows to increase the bandwidthwhile minimizing the latency. Dynamic reconfiguration of the interconnect allowsto handle the heterogeneity of communications. We present the rationale for choos-ing RF over optics and 3D, the detailed architecture of the network and the chipimplementing it, the evaluation of its feasibility and its performances. During theevaluation phase we were able to show that for a CMP of 1 024 tiles, our solutionallowed a performance gain of 13 %. One advantage of this RF interconnect is theability to broadcast without additional cost compared to point-to-point communi-cations, opening new perspectives in terms of cache coherence.

abstract: This dissertation focuses on three different efficiency enhancement methods that are applicable to handset applications. These proposed designs are based on three critical requirements for handset application: 1) Small form factor, 2) CMOS compatibility and 3) high power handling. The three presented methodologies are listed below: 1) A transformer-based power combiner architecture for out-phasing transmitters 2) A current steering DAC-based average power tracking circuit for on-chip power amplifiers (PA) 3) A CMOS-based driver stage for GaN-based switched-mode power amplifiers applicable to fully digital transmitters This thesis highlights the trends in wireless handsets, the motivates the need for fully-integrated CMOS power amplifier solutions and presents the three novel techniques for reconfigurable and digital CMOS-based PAs. Chapter 3, presents the transformer-based power combiner for out-phasing transmitters. The simulation results reveal that this technique is able to shrink the power combiner area, which is one of the largest parts of the transmitter, by about 50% and as a result, enhances the output power density by 3dB. The average power tracking technique (APT) integrated with an on-chip CMOS-based power amplifier is explained in Chapter 4. This system is able to achieve up to 32dBm saturated output power with a linear power gain of 20dB in a 45nm CMOS SOI process. The maximum efficiency improvement is about ∆η=15% compared to the same PA without APT. Measurement results show that the proposed method is able to amplify an enhanced-EDGE modulated input signal with a data rate of 70.83kb/sec and generate more than 27dBm of average output power with EVM<5%. Although small form factor, high battery lifetime, and high volume integration motivate the need for fully digital CMOS transmitters, the output power generated by this type of transmitter is not high enough to satisfy the communication standards. As a result, compound materials such as GaN or GaAs are usually being used in handset applications to increase the output power. Chapter 5 focuses on the analysis and design of two CMOS based driver architectures (cascode and house of cards) for driving a GaN power amplifier. The presented results show that the drivers are able to generate ∆Vout=5V, which is required by the compound transistor, and operate up to 2GHz. Since the CMOS driver is expected to drive an off-chip capacitive load, the interface components, such as bond wires, and decoupling and pad capacitors, play a critical role in the output transient response. Therefore, extensive analysis and simulation results have been done on the interface circuits to investigate their effects on RF transmitter performance. The presented results show that the maximum operating frequency when the driver is connected to a 4pF capacitive load is about 2GHz, which is perfectly matched with the reported values in prior literature. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2019

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