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. 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. 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.

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. 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. 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. 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.

This dissertation divides into three parts: (a) design and research of asymmetric stepped impedance resonator (SIR); (b) design and fabrication of dual-band and ultra-wide band (UWB) bandpass filters (BPFs) and (c) design and fabrication of millimeter wave filters. (a)design and research of asymmetric stepped impedance resonator. In the first part of the dissertation, we propose an asymmetric SIR, and the effect of electrical length ratio and impedance ratio on the performance of frequency has been discussed in detail. The insertion loss and spurious can be controlled by the structural parameters of asymmetric SIR which decreases the length of resonator effectively and achieves the reduction of whole size. Additionally, this characterization of the asymmetric SIR can be extensively applied on the interconnection of RFIC. (b) design and fabrication of dual-band and ultra-wide band (UWB) filters. In the second part of the dissertation, we propose dual-band and UWB BPFs by using asymmetric SIRs. The designed dual-band BPF is conformed to the standard of wireless local area network (WLAN), and the designed UWB BPF is conformed to the standard that Federal Communications Commission (FCC) defined. The structural parameters of asymmetric SIR can be adjusted accurately by the theoretical equations we calculated. Then, the ideal performance can be achieved. (c) design and fabrication of millimeter wave filters. In the third part of the dissertation, we propose the design of millimeter wave filters fabricated by the standard of complementary metal-oxide semiconductor (CMOS). Asymmetric SIRs are used to design the microwave filter to estimate that the feasibility of system on chip (SoC). Finally, some suggestions are made in the future work on technology for system on chip (SoC).

Ultra Wide Band (UWB) is a short-pulse signal which has extremely potential in wireless communication system due to the advantages of high data rate, better immunity to multipath fading, wide bandwidth, and high capability. According to the Federal Communications Commission (F.C.C.), UWB only can be transmitted in short distance of a few to tens of meters due to low power density (-41.3dBm/MHz). However, optical fiber has low loss and cost and wide bandwidth, so it can be achieved in wide area network. In this work, we propose a novel method to generate optical UWB doublet pulse without complicated setup. When electroabsorption modulator (EAM) integrating a taper optical directional coupler (TODC) was applied field, the transmission loss and coupling would change resulting from the absorption coefficient and effective index of active waveguide with the applied field. So, we used a single mode fiber collecting the power after the device, we could get the valley shape transfer function. Using the transfer function of electro-absorption modulator (EAM) integrating TODC we inject a Gaussian pulse into the EAM in the range of valley shape, and it can transform an electrical pulse into optical UWB doublet pulse by acceptable operating point. Therefore, the optical signals could be transmitted in optical fiber so that it can reduce loss of the electro-optic transformation. Experimentally, the full wave at half maximum of doublet pulse, 10dB bandwidth, fractional bandwidth were 75ps, 7.5GHz, 125%, respectively, and power density was less than -41.3dBm/MHz. These were all meeting the F.C.C. standard. In the future, we will use long distant optical fiber to transmitted UWB signal, and compare with different distance. Finally, we will check the UWB signal can be transmitted in optical fiber to achieve wide range signal transmission by bit error rate test.

Ultra-wide band (UWB) 6-9 GHz antenna, band pass filter and low-noise amplifier (LNA) optimization using co-simulation of the RF front-end. At higher frequencies, carefully conducted design methodologies are required for RF front-end parameter optimization, such as power gain and low noise figure with low power consumption.

No description available.

Ce mémoire présente une méthodologie de conception d’antennes Ultra Large Bande volumiques à ondes progressives, d’encombrement réduit, dédiées au rayonnement d’impulsions ultra-courtes dans une bande de fréquence allant de 300 MHz à 3 GHz. L’objectif est de concilier une large bande de fréquences rayonnées et de bonnes performances de rayonnements transitoires (niveau élevé, signaux brefs) tout en limitant l’encombrement des antennes. L’insertion d’un matériau diélectrique a été associée au design des antennes ULB afin de réduire leurs dimensions. Ceci a conduit à la synthèse et à la caractérisation de matériaux diélectriques innovants à base de géopolymères, dont la maîtrise de la valeur de la permittivité est possible. Un prototype d’antenne a été réalisé, des mesures des différentes caractéristiques de rayonnement ont été effectuées et comparées aux résultats de simulation pour s’assurer du bon fonctionnement de celle-ci. Cette antenne a également été associée à des applications radar pour la détection de cibles se situant dans différents milieux (air et sol). Les réponses impulsionnelles obtenues pour les différentes scènes radar testées ont été comparées aux résultats mesurées avec d’autres antennes connues. / This thesis presents the design of small form factor Ultra Wide Band antennas with progressive waves shape, which is dedicated to ultra-short pulses radiation in a frequency band ranging from 300MHz to 3GHz. The aim is to combine a wide band of radiated frequencies and good performance while limiting the size of antennas. The insertion of a dielectric material has been associated with the design of Ultra Wide Band antennas to reduce their dimensions. This has led to the synthesis and characterization of innovative dielectric materials based on geopolymers, whose mastering of the value of the permittivity is possible. An antenna prototype has been manufactured and measurements of the different radiation characteristics were made and compared to the simulation results to ensure its good functioning. This antenna has also been associated with radar applications for the detection of targets in different environments (air and soil). The impulse responses obtained for the different tested radar scenes have been compared with the results obtained with other known antennas.

With the population aging worldwide, new solutions for non-invasive health monitoring are required. Radar systems have been proposed as a promising technology for monitoring vital signs in ambient assisted living (AAL) applications. Monitoring vital signs such as breathing rate, heart rate, and pulse rate can provide crucial insights into human well-being and detect a wide range of medical problems. The main focus of mm-wave radar applications is currently geared towards the automotive market; however, several potential application areas within the broad industrial and healthcare domain are also under active investigation. Their major advantage is that, without the need for any cable or electrode, it is possible, at first, to locate the patient inside the room and, then, to measure their respiratory rate and heartbeat. A contactless detection method offers the simple and fast monitoring of vital signs without the disadvantages of current practices. One very promising approach is the use of radar technology. This thesis focuses on finding the safe way of using mm-Wave propagation in a hospital's real-world scenario and finding the safe range of frequency and power dissipation that won’t be harmful to the human body.  Objective: In this thesis, we investigate the optimum range of frequency and power of mm-Wave propagation, which can be considered safe for usage in an environment like hospitals. Also, the range of power with respect to the power density which can be considered safe for implementation in E-health systems.  Methods: Simulation is considered the method to find various range brackets for different parameters like frequencies, distances, bandwidths, and power. The simulation also helps to get a large number of results for a closer approximation. The received signal is observed to get the desired results, and using the available data, the ranges are found for safe usage of the forementioned technologies.  Results: The results obtained are tabulated to show the relation of received signal strength with all the other parameters like frequency, distance, and power. Then using the power and received signal relation, the safe range of power is calculated, which can be used in a closed environment like hospitals.

<p>The first flexible chip-less RFID temperature sensor system for food monitoring to have a  resolution of 0.2  <strong>°</strong>C for temperature measurements between 79  <strong>°</strong>C and -22.8  <strong>°</strong>C is introduced. This  system has a significant improvement in temperature range compared to current flexible RFID  sensors and can provide high accuracy measurements for real time food monitoring at the system  level. Flexible sensors provide low-cost, better flexibility, and longer service life; hence, flexible  sensor systems can provide a new future for food monitoring in commercial applications. The  proposed system presents a new feature and enables a food monitoring system that utilizes a  flexible sensor system. The system introduced in this paper enables a wireless measurement system  providing 100 dB dynamic range with 160 Msps and 16-bit resolution for precise temperature  measurements that are critical for food quality within 100  <strong>°</strong>C temperature range. The full sensing  system is designed, tested and measurements results are confirmed to be within expected accuracy </p>

This thesis explores the possibility of using ultra wideband technology to localize anoutdoor mobile robot. More explicitly, this project focuses on the multilaterationproblem where the topology of the static reference anchors are changed. Insteadof having stationary anchors they are placed on a mobile robot and by pinpointingone single static tag node the position of the robot is established. The research usesa robotic lawn mover from Husqvarna, the Automover 430X. The robot is used asa base platform for this thesis to evaluate if this approach is applicable for othergeneric robots in the same size. The feasibility of this solution is demonstratedthrough simulation using Matlab and the robot simulation environment Gazebo.Results show that this specific topology is feasible for tracking a specific point butis also suitable for positioning a mobile robot if coupled with an accurate headingsensor. The system was evaluated for several scenarios of which all indicated anadequate accuracy, provided that data from an encoder was used. The upper limitfor the position error in a one sided 95% confidence interval was 0.469m at a rangeof 40m. / Detta examensarbete tar sig an problemet att lokalisera en långsamtgående mobilrobot i en utomhusmiljö genom att använda sig av ultra wideband radioteknik. Vanligtvisplaceras stationära noder i miljön som används för att positionera en ensamnod i dess närhet. Detta projekt tar sig an frågeställningen om det är möjligt attvända på problemet och placera dessa stationära noder på den mobila roboten föratt sedan fixera robotens position genom att bestämma vart den ensamma nodenär placerad. Husqvarnas robotgräsklippare Automover 430X har används som plattformför att evaluera och testa om denna tes är applicerbar för andra generiska robotari samma storlek. Positionsuppskattningen utförs genom simulationer i Matlabsamt simulationsmiljön Gazebo som tar hänsyn till diverse fysiska fenomen. Resultatenpekar på att denna topologi är möjlig för att lösa multilatereringsproblemetom en riktningssensor med hög precision används. För alla scenarion som simuleradesindikerades att en någorlunda god precision kan uppnås och det krävdes attsystemet kombinerades med annan indata, som en enkoder i detta fall för att förbättraestimeringen. Den övre gränsen för felet i ett 95% konfidensintervall var 0.469mpå ett avstånd upp till 40m.