Design and Analysis of Various Handset Antennas with the Aid of HFSS

In this thesis, an attempt is made to present the design of handset antennas, the proposed handset acts as a thin wire model that represents the backbone of the final antenna. The designed antenna parameters are subjected to optimization to fit into the desired frequency bands. Different antenna types are used, such as wire antennas and planar antennas designed using theHFSS.The design of basic antennas for handset applications, experimented with a simple monopole and dipole in a 3-D form. The monopole and dipole used in handset antennas provides multi-band and broadband properties that cover the desired frequency bands in the handset antennas. The design experiment and analysis of a continuous and unbroken metal rimmed antenna with a monopole which is directly fed with a patch acts as aloo antenna in smart phone applications is proposed. The antenna proposed here provides a straight forward and a good multi-band antenna result for anprotected metal rimmed smart phone. The protected rim and two no-ground portions are set on the both the top and bottom sides of the system circuit board, respectively. The system ground is surrounded between the two no ground portions which are connected to the metal rim with a small grounded patch which divides the unbroken metal rim into two strips. Atlast the dualloop antenna is formed by adjusting the ground plane and the micro strip ina proper way. The design antenna is operated on several number of GSM bands.The second design is study of a balanced antenna with folded architecturefor mobile handset applications with dual-frequency performance (2.40 GHzand 5.00 GHz) for WLAN applications are discussed. The thin-strip planardipole is used as an antenna with folded architecture and two arms on eachmonopole. The folded architectures one on the left and other on the rightacts as a dipole and are capable of providing the multiple bands .The antenna performance is featured by using the antenna radiation pattern,returnloss, power gain and surface current distribution of the antenna. The parametric studies are carried out by varying the antenna height and width of1 mm each, the parameters are optimized for steered impedance matchingwithin the range of frequency bands for both the WLAN and short distance communication systems.The third design is focused on the frequency band (1.8 GHz to 2.45 GHz)in which the balanced antenna for applications of mobile handsets with abandwidth of highly improved performance. The slot planar dipole is usedan antenna here with folded architecture and is having a dual arm on boththe sides of the ground plane. The S-parameter method is used to findthe antenna impedance. In order to obtain the power gain measurementin the antenna.The balanced feed from an unbalanced source is supportedby planar balun which is of wide bandwidth to get the desired gain. The results measured provides a good agreement and also provides good wideband characteristic

Balanced antennas for mobile handset applications. Simulation and Measurement of Balanced Antennas for Mobile Handsets, investigating Specific Absorption Rate when operated near the human body, and a Coplanar Waveguide alternative to the Balanced Feed.

The main objectives of this research are to investigate and design low profile antennas for mobile handsets applications using the balanced concept. These antennas are considered to cover a wide range of wireless standards such as: DCS (1710¿1880 MHz), PCS (1850¿1990 MHz), UMTS (1920¿2170 MHz), WLAN (2400¿2500 MHz and 5000 ¿ 5800 MHz) and UWB frequency bands. Various antennas are implemented based on built-in planar dipole with a folded arm structure. The performance of several designed antennas in terms of input return loss, radiation patterns, radiation efficiency and power gain are presented and several remarkable results are obtained. The measurements confirm the theoretical design concept and show reasonable agreement with computations. The stability performance of the proposed antenna is also evaluated by analysing the current distribution on the mobile phone ground plane. The specific absorption rate (SAR) performance of the antenna is also studied experimentally by measuring antenna near field exposure. The measurement results are correlated with the calculated ones. A new dual-band balanced antenna using coplanar waveguide structure is also proposed, discussed and tested; this is intended to eliminate the balanced feed network. The predicted and measured results show good agreement, confirming good impedance bandwidth characteristics and excellent dual-band performance. In addition, a hybrid method to model the human body interaction with a dual band balanced antenna structure covering the 2.4 GHz and 5.2 GHz bands is presented. Results for several test cases of antenna locations on the body are presented and discussed. The near and far fields were incorporated to provide a full understanding of the impact on human tissue. The cumulative distribution function of the radiation efficiency and absorbed power are also evaluated.UK Engineering and Physical Sciences Research Council (EPSRC

Design of new wearable antennas and textile-based transmission lines

Flexible wearable antennas and their components are a fast growing research topic in modern communication systems. They are developed for various wearable applica tions, such as health monitoring, fitness tracking, rescuing, and telecommunications. Wearable antennas need to be compact, lightweight, flexible, and robust. In this thesis, two dual-band wearable antennas were developed, each with a differ ent design approach. The first antenna is a dual-band flexible folded shorted patch (FSP) antenna which operates at 400 MHz and 2.4 GHz. It uses polydimethylsilox ane (PDMS), which is low cost, flexible and robust, and is used as a substrate for wearable the FSP antenna. In addition, the FSP antenna also exploits the TM010 and TM001 modes. A comparative study was carried out to analyze the far-field radiation and directivity at the TM010 and TM001 modes between the FSP antenna and a conventional patch antenna using cavity model analysis. The proposed FSP antenna is suitable for military search and rescue operations and emergency services. The second antenna is a dual-band flexible circular polarized (CP) patch antenna operational at 1.575 GHz and 2.45 GHz. Kevlar was used as a substrate for the proposed antenna. The patch consists of truncated corners and four diagonal slits. An artificial magnetic conductor (AMC) plane was integrated within the design in order to reduce the backward scattered radiation towards the human body and also to improve the realized gain of the antenna. The AMC unit cell design consists of square slits, a square ring and was integrated as a 3 × 3 array of square patch AMC unit cells. The proposed antenna developed is suitable for WBAN and WLAN applications. A circular polarized (CP) patch antenna with a PDMS substrate was also designed and fabricated to test the durability and resiliency of PDMS as a polymer-based material suitable for use in wearable antennas. Robustness tests such as bent, wet, and temperature tests were performed and reported. Two prototypes of flexible wearable coaxial transmission lines were also designed and fabricated. Polyester (PES) and polytetrafluoroethylene (PTFE) textile materials were used to design prototypes of these cables. Shielding effectiveness and DC losses were measured and compared for the fabricated cables. The cables were also tested for bending, twisting and for suitability in environmental conditions. The highly flexible nature of these cables makes them suitable to use with wearable antennas for various applications. For example, the proposed cables can be used with previously detailed FPS antenna for military search and rescue operations. It should be mentioned that this thesis was done in collaboration with Leonardo, UK and J&D Wilkie, UK

1-D broadside-radiating leaky-wave antenna based on a numerically synthesized impedance surface

A newly-developed deterministic numerical technique for the automated design of metasurface antennas is applied here for the first time to the design of a 1-D printed Leaky-Wave Antenna (LWA) for broadside radiation. The surface impedance synthesis process does not require any a priori knowledge on the impedance pattern, and starts from a mask constraint on the desired far-field and practical bounds on the unit cell impedance values. The designed reactance surface for broadside radiation exhibits a non conventional patterning; this highlights the merit of using an automated design process for a design well known to be challenging for analytical methods. The antenna is physically implemented with an array of metal strips with varying gap widths and simulation results show very good agreement with the predicted performance

Beam scanning by liquid-crystal biasing in a modified SIW structure

A fixed-frequency beam-scanning 1D antenna based on Liquid Crystals (LCs) is designed for application in 2D scanning with lateral alignment. The 2D array environment imposes full decoupling of adjacent 1D antennas, which often conflicts with the LC requirement of DC biasing: the proposed design accommodates both. The LC medium is placed inside a Substrate Integrated Waveguide (SIW) modified to work as a Groove Gap Waveguide, with radiating slots etched on the upper broad wall, that radiates as a Leaky-Wave Antenna (LWA). This allows effective application of the DC bias voltage needed for tuning the LCs. At the same time, the RF field remains laterally confined, enabling the possibility to lay several antennas in parallel and achieve 2D beam scanning. The design is validated by simulation employing the actual properties of a commercial LC medium

Non-Invasive Blood Glucose Monitoring Using Electromagnetic Sensors

Monitoring glycemia levels in people with diabetes has developed rapidly over the last decade. A broad range of easy-to-use systems of reliable accuracies are now deployed in the market following the introduction of the invasive self-monitoring blood glucose meters (i.e., Glucometers) that utilize the capillary blood samples from the fingertips of diabetic patients. Besides, semi-invasive continuous monitors (CGM) are currently being used to quantify the glucose analyte in interstitial fluids (ISF) using an implantable needle-like electrochemical sensors. However, the limitations and discomforts associated with these finger-pricking and implantable point-of-care devices have established a new demand for complete non-invasive pain-free and low-cost blood glucose monitors to allow for more frequent and convenient glucose checks and thereby contribute more generously to diabetes care and prevention. Towards that goal, researchers have been developing alternative techniques that are more convenient, affordable, pain-free, and can be used for continuous non-invasive blood glucose monitoring. In this research, a variety of electromagnetic sensing techniques were developed for reliably monitoring the blood glucose levels of clinical relevance to diabetes using the non-ionizing electromagnetic radiations of no hazards when penetrating the body. The sensing structures and devices introduced in this study were designed to operate in specific frequency spectrums that promise a reliable and sensitive glucose detection from centimeter- to millimeter-wave bands. Particularly, three different technologies were proposed and investigated at the Centre for Intelligent Antenna and Radio Systems (CIARS): Complementary Split-Ring Resonators (CSRRs), Whispering Gallery Modes (WGMs) sensors, and Frequency-Modulated Continuous-Wave (FMCW) millimeter-Wave Radars. Multiple sensing devices were developed using those proposed technologies in the micro/millimeter-wave spectrums of interest. A comprehensive study was conducted for the functionality, sensitivity, and repeatability analysis of each sensing device. Particularly, the sensors were thoroughly designed, optimized, fabricated, and practically tested in the laboratory with the desired glucose sensitivity performance. Different topologies and configurations of the proposed sensors were studied and compared in sensitivity using experimental and numerical analysis tools. Besides, machine learning and signal processing tools were intelligently applied to analyze the frequency responses of the sensors and reliably identify different glucose levels. The developed glucose sensors were coupled with frequency-compatible radar boards to realize small mobile glucose sensing systems of reduced cost. The proposed sensors, beside their impressive detection capability of the diabetes-spectrum glucose concentrations, are endowed with favourable advantages of simple fabrication, low-power consumption, miniaturized compact sizing, non-ionizing radiation, and minimum health risk or impact for human beings. Such attractive features promote the proposed sensors as possible candidates for development as mobile, portable/wearable gadgets for affordable non-invasive blood glucose monitoring for diabetes. The introduced sensing structures could also be employed for other vital sensing applications such as liquid type/quantity identification, oil adulteration detection, milk quality control, and virus/bacteria detection. Another focus of this thesis is to investigate the electromagnetic behavior of the glucose in blood mimicking tissues across the microwave spectrum from 200 MHz to 67 GHz using a commercial characterization system (DAK-TL) developed by SPEAG. This is beneficial to locate the promising frequency spectrums that are most responsive to slight variations in glucose concentrations, and to identify the amount of change in the dielectric properties due to different concentrations of interest. Besides, the effect of the blood typing and medication was also investigated by measuring the dielectric properties of synthetic “artificial” as well as authentic “human” blood samples of different ABO-Rh types and with different medications. Measured results have posed for other factors that may impact the developed microwave sensors accuracy and sensitivity including the patient’s blood type, pre-existing medical conditions, or other illnesses

Potentiel de la technologie MID pour les composants passifs et des antennes

MID (Molded Interconnect Devices) technology, owing to their electrical performance,flexibility in RF circuits, its potential to reduce the number of components, process steps andminiaturization of the final product, has led to some new constraints to the RF (RadioFrequency) and microwave domain. Molded components are interconnected withthermoplastic substrates and conductive traces are injected on the surface. The objective ofthis thesis is to study the compatibility of MIDs for RF applications. The advantages of MIDtechnology in the RF domain is exploited for transmission lines, passive filters, directionalcouplers and planar and 3D antennas realization. The RF characterization of various MIDsubstrate materials and the study of the performance of the above RF components based onvarious MID fabrication technologies are included in the thesis. Finally, an permittivityimprovement study of some thermoplastics are also studied.La technologie MID (Molded Interconnect Device), fait de leur performance électrique, la flexibilitédans les circuits RF, le potentiel de réduire le nombre de composants, les étapes du processus et laminiaturisation du produit final, a conduit à de nouvelles contraintes à la RF (Radio Frequency) et ledomaine des micro-ondes. Composants moulés sont interconnectées avec des substratsthermoplastiques et les pistes conductrices sont injectés sur la surface. L'objectif de cette thèse estd'étudier la compatibilité de MID pour les applications RF. Les avantages de la technologie MID dansle domaine RF est exploitée pour les lignes de transmission, filtres passifs, coupleurs directionnels etantennes réalisation. La caractérisation RF de différents matériaux de substrat MID et l'étude de laperformance des composants RF ci-dessus sur la base de différentes technologies de fabrication MIDsont inclus dans la thèse. Enfin, le concept d'une étude d'amélioration de la permittivité de certainsthermoplastiques sont également étudiés

Intelligent Circuits and Systems

ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.　 This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering

Technology for large space systems: A bibliography with indexes (supplement 16)

This bibliography lists 673 reports, articles and other documents introduced into the NASA scientific and technical information system between July 1, 1986 and December 31, 1986. Its purpose is to provide helpful information to the researcher, manager, and designer in technology development and mission design according to system interactive analysis and design, structural and thermal analysis and design, structural concepts and control systems, electronics, advanced materials, assembly concepts, propulsion, and solar power satellite systems