ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / This paper baselines the performance of common, single band telemetry blade antennas in two telemetry bands and compares that performance to two very differing multi-band antenna designs. A description of each antenna is presented followed by flight testing results and conclusions. Results are in the form of received signal strength versus geographic location, derived in-flight antenna patterns, link availability, and bit error analysis.

ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada / The Isotropic radiator, a device capable of radiating energy evenly in all directions is an abstraction, itsʼ real counterpart is called an omnidirectional (omni) antenna. The omnidirectional antenna is found on many vehicles. Ideally, only one receiving system is ever needed to acquire an omni, no matter the vehicle orientation, given the range is not excessive. There are trade-offs with antenna efficiency, with gain typically around -15 dBi (95% coverage). This paper proposes abandoning this paradigm. If a vehicle knows where the ground is why radiate energy up into the sky, where there are no receiving stations. This can be achieved by integrating some instrumentation with a discrete antenna array so that it radiates only from selected elements. The accuracy required is modest, an inexpensive Inertial Measurement Unit (IMU) is sufficient to improve link margin by 10, 20dB or more. These numbers are credible, as outlandish as they are, and substantiated in this paper. Ironically, from the ground this non-isotropic antenna looks very isotropic. Of significant benefit, this Smarter Antenna concept enables spatial discrimination and with that comes spectrum efficiency gains beyond that achieved by other means including advanced modulation formats.

This thesis examines the use of two coupled loops as an alternative method of connection for high frequency signals between passive elements on microwave laminates and integrated circuits; replacing traditional interconnect methods such as wire bonds and solder bumps which require costly back end of line processing. The loops harness both electric and magnetic fields in order to create the interconnection, and can be placed around the perimeter of the IC; here they do not interfere with placement of the existing electronics on the chip, or occupy space which may be required for large components such as spiral inductors. A parametric model for these coupled loops was developed in this thesis. This model allows for rapid initial dimension choice when provided a variety of different parameters such as the IC process geometry, and loop stack geometry. Once initial dimensions are obtained from the model, full-wave simulation can be used to finalize the design and examine effects of process design rules such as metal density requirements. Following model development a prototype system, consisting of a two metallic loops (one located on a low-loss microwave laminate, the other on a 0.13 u m CMOS IC), was fabricated. These loops were then stacked in order to couple the signal from a planar antenna array (printed on the laminate) onto the IC. This antenna-to-chip system was simulated and measured to have center frequencies of 25 GHz and 23 GHz respectively, with a peak gain greater than 5 dBi at the beams broadside (8 dBi in simulation). These results agree quite well, with discrepancies arising primarily from the presence of adhesive between the loops. This adhesive wicked underneath the IC during assembly, which was not accounted for during simulation, but can easily be done so. The radiation pattern from the antenna was measured to have a HPBW of 16 degrees in the elevation plane and 100 degrees in the azimuth plane. These correspond nicely with simulated results and produce a suitable system for automotive radar application; where harsh environments present difficulties to current interconnects such as wire bonds. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2013-09-09 21:55:06.971

Master of Science / Department of Electrical and Computer Engineering / William B. Kuhn / This work was a part of NASA EPSCoR Project NNX11AM05A: Biosensor Networks and Telecommunication Subsystems for Long Duration Missions, EVA Suits, and Robotic Precursor Scout Missions. The project’s main goal is the development of a wireless sensor network inside an astronaut’s spacesuit. Antennas are essential components in a wireless network. Since this antenna will be used inside the spacesuit it is important to consider both the physical size limitations and the desired antenna polarization. After exploring the WWVB radio station antenna which provides the preferred vertical polarization and has a suitable aspect ratio, the top hat antenna seemed promising for intrasuit communication. The design of a top hat antenna is outlined. Then, the antennas were tested using 433 MHz radios in a full scale model spacesuit. This spacesuit was designed specifically to model the behavior of aluminized mylar in the real suit. Test results support the feasibility of an intrasuit wireless network. If a gateway radio is placed on the chest or back, a sensor could be placed anywhere on the body and provide an adequate signal. These initial tests did not include a matching network, but the additional link-margin afforded by a matching network, even an imperfect match, is considered. Energy harvesting is explored as an alternative to batteries powering the intrasuit radio. In the oxygen rich environment of a spacesuit, even the smallest spark can be catastrophic. A variety of energy harvesting options are explored with a focus on thermal energy harvesting. The temperature difference between the human skin and the astronaut’s Liquid Cooling and Ventilation Garment can be used to produce a small voltage. To increase the voltage a step-up converter is implemented. Final integration of the two systems with a biosensor is left for on-going work in the three year NASA project.

Afin de répondre à la demande croissante de nouveaux services, les objets que nous utilisons au quotidien (les smartphones, les voitures, les avions, etc.) tendent à intégrer de plus en plus de systèmes radio tandis que l’espace disponible pour l’intégration de ces éléments est de plus en plus réduit. Ces systèmes radio nécessitent l’utilisation de plusieurs antennes devant répondre à des critères de compacité, d’isolation, de coût, etc. À titre d’illustration, un smartphone contient plusieurs antennes pour assurer des fonctions telles que la téléphonie, la navigation, la connexion à internet par WiFi, les liaisons Bluetooth, la technologie NFC (Near-Field Communications) et ce nombre tend à s’accroitre considérablement avec l’émergence de nouveaux services. Le même phénomène se retrouve également au niveau des plateformes aéroportées où des fonctions telles que la communication, la navigation, le radar, etc. sont utilisées. Cela conduit donc à la nécessité de réduire le nombre d’antennes en regroupant par exemple plusieurs fonctions au sein d’une même et unique antenne. Dans de précédents travaux de recherches, J. Euzière a démontré la possibilité de combiner une fonction radar et une seconde fonction (ici de communication) en utilisant un réseau de 16 monopoles initialement dédié au seul radar, grâce au Time Modulated Array (TMA). De cette façon, les deux fonctions utilisaient la même fréquence et étaient alimentées par une seule source. L’objectif principal de cette thèse est de proposer une solution d’antenne multifonction pour radar et communication encore plus compacte (constituée d’une seule antenne). L’idée est de partir d’une solution antennaire déjà existante et d’y apporter les modifications nécessaires à l’ajout d’une seconde fonction, sans pour autant augmenter la surface de l’antenne ni la complexité du système. / In order to respond to the increasingly demand of new services, the objects we use on a daily basis (such as mobile phones, cars, airplanes etc.), tend to integrate more and more radio systems while the space available is limited. These radio systems require the use of many antennas that must meet multiple requirements such as compactness, isolation, costs, etc. A smart-phone, for example, contains several antennas for global navigation satellite system (GNSS), WiFi, TV, FM radio, Bluetooth, near-field communications (NFC) and the number is expected to increase as new systems are added. Another example is in airborne platforms where multiple functions such as communication, navigation, radar, electronic warfare are used. This leads to the need of reducing the number of associated antennas by regrouping several radio functions into a single antenna. However, combining the functionality of several antennas into one shared radiating element while maintaining the functionality of the various radio systems presents a great challenge. During its Ph.D, J. Euzière demonstrated the possibility to combine a radar function and a secondary function from a 16-monopole array originally dedicated to radar operation by using Time Modulated Array (TMA) technique. By this way, the two functions were operating at the same frequency and the system was powered by a single source.The main objective of this thesis is to propose a more compact antenna (a single antenna) dedicated to radar and communication operations instead of using antenna array as J. Euzière did it. The idea is to start from an existing antenna solution and make the necessary modifications to add a second function without adding additional surface and complexity. As we are interested in radar applications, we will choose a directive antenna: a horn antenna. The goal is then to study the possibility to modify the radiation pattern of the horn antenna through controllable elements (slots) and to transmit a direct modulated signal at the antenna level for the communication function. Furthermore, polarization diversity is an attractive way to increase the isolation between two applications. Thus, this aspect will be taken into account in the design of the antenna solution.

Une des problématiques qui est souvent associée aux réseaux large bande est l’apparition des lobes de réseaux, liée à la périodicité de l’espacement entre les éléments du réseau. Un autre problème dans les réseaux large bande est la fréquence de fonctionnement de l’élément du réseau. La plus basse fréquence d’opération est généralement liée à la taille de l’élément. Dans cette thèse un réseau d’anneaux concentriques a été développé. Les connections entre les spirales de polarisation opposée diminuent le coefficient de réflexion dans les fréquences basses. La topologie des anneaux concentriques a été optimisée avec des Algorithmes Génétiques pour minimiser le niveau des lobes secondaires relatifs dans les hautes fréquences. L’addition d’une contrainte de taille dans la procédure d’optimisation a assuré que le réseau soit compact. Le réseau optimisé opère entre 1 et 6.9 GHz. Le design a été d’avantage développé avec la technique WAVES avec l’inclusion d’une copie réduite en son centre, ce qu’a permis l’extension de la bande passante jusque 13 GHz. De plus, nous avons proposé un nouveau design pour le réseau de spirales connectés qui consiste en des antennes spirales disposées dans un réseau uniforme avec les bras connectés aux bras des antennes voisines. Les simulations indiquent que le réseau peut avoir une bande passante arbitrairement large selon la finitude du réseau. Un prototype a été construit et mesuré pour valider le concept. / One of the usual problems associated with wideband arrays is having the highest frequency of operation limited by the appearance of grating lobes, associated with the periodicity in the spacing between elements of the array. Another issue is the working frequency of the element of the array. The lowest frequency of operation is in general related to the size of the element. In this thesis a Concentric Ring Array of Connecting Spirals has been developed. The connections between spirals of opposite polarizations reduces the reflection coefficient at lower frequencies. The concentric rings topology had the radius and relative rotations of each ring optimized using Genetic Algorithms to minimize the RSLL at higher frequencies. The addition of a size constraint in the optimization procedure kept the array compact. The optimized array operates from 1 to 6.9 GHz. The design was then updated using the WAVES technique to include a scaled down copy in its center, extending the bandwidth of the array up to 13 GHz. Moreover, we proposed a new design for the array of connected spirals which consists of arranging spirals in a uniform array and connecting the arms of the neighboring spirals. Simulations indicate that the design can have an arbitrarily large bandwidth depending on the finiteness of the array. A prototype has been built and measured to validate the concept.

Traditional antennas have a lot of limitations as their performance is usually fixed by their initial geometry. On the other hand, modern communication systems are getting way to complicated compared to their earlier counterparts. This necessitates some special types of smart or reconfigurable antennas, which can dynamically adapt to the requirements of the communication systems more effectively. Using conventional single functional antennas is therefore not an efficient approach in these sort of communication systems. Considering all these factors, in this thesis, a beam steerable reconfigurable antenna system is presented that can yield the radiation patterns of multiple antennas with a single structure, necessary for 5G communication. This antenna system occupies comparatively much smaller space and can provide highly directive gain at different directions. It is expected that- in near future, further improvements of this type of antenna system can be performed to pave the way for some additional necessary functions required in modern communication systems.

Antennas enable wireless communication by transmission and reception of electromagnetic (EM) signals, which carry information is space. Signal reception and hence the quality of service depends significantly on the antenna properties, e.g. radiation pattern, operational frequency, and polarization. Legacy antennas, with their fixed properties, fail to adapt to the changing environment and degrade signal quality. Reconfigurable antennas (Ras) capable of changing their properties dynamically increase the capacity and data rate of wireless systems while offering a compact design. However, these advantages come at the cost of increased complexity compared to legacy antennas. Therefore it is important to design Ras with minimal complexity. To that end, this dissertation focuses on the development of a novel approach, three different Ras operation at three different frequency bands have been designed, fabricated and characterized. First RA works at the 5GHz band (4.9-5.1GHz) and obtains on current beam steering and 3-dB beam width variability. An algorithm to choose the optimum mode of operation has also been developed. The design approach introduced in first RA has been exploited to design the second RA, which achieves beam steering and beam width variability for two polarizations and operates a the 28 GHz band (27.5-28.3 GHz). The third RA operates at the 3GHz band and simultaneously reconfigures impedance and radiation patterns.

The aim of this project is to design a microstrip phase array antenna in ADS (Advance Design System) Momentum. The resonant frequency of which is 10 GHz. Two circular patches with a radius of 5.83 mm each are used in designing the array antenna. RT-DURROID 5880 is used as a substrate for this microstrip patch array design. These circular patches are excited using coaxial probe feed and transmission lines of particular lengths and widths. These transmission lines perfectly match the impedance of the circular patches. Various parameters, for example the S-parameters, two dimensional and three dimensional radiation patterns, excitation models, gain, directivity and efficiency of the designed antenna are obtained from ADS Momentum.

The purpose of this research is to find ways to create an omnidirectional antenna with high directivity in the vertical plane. The investigation is based on computer simulation using the program CST 2011. The objective is a narrow-band antenna that is omnidirectional in the horizontal plane and has maximum achievable directivity for a fixed size. Three of the most promising antenna designs are selected based on the current state of antenna technology. Their maximum directivities are estimated by means of well known relations in antenna theory. It is shown that the most suitable design is an omnidirectional antenna in the form of a cylindrical dipole antenna array with an active central dipole. For this antenna, excitation by means of a radial traveling wave, with a phase velocity smaller than speed of the light, is possible. It is found that for a certain value of a moderating factor it is possible to obtain a directivity that is 2.5 – 3 dB larger than that of a dipole or a linear antenna with uniform excitation. The antenna structures are modeled to determine the number of dipoles, their dimensions and the spacing between them that maximizes the directivity.