Dually-Polarized Microwave Components Based on Polarization-Selective Coupling for Green Wireless Systems

RÉSUMÉ Avec le développement rapide et continu de technologies et de réseaux sans fil de nouvelle génération tels que la 5G et avec les ressources limitées d'énergie et de spectre disponibles pour soutenir ces développements sans fil rapides, l'exploration des bandes millimétriques sous-utilisées devient incontournable. Il devient de plus en plus crucial de se concentrer sur la réduction de la consommation d'énergie dans les futurs systèmes sans fil. Le moyen le plus efficace de réception d'énergie d'onde électromagnétique est de capturer complètement les deux composantes orthogonales de son vecteur de champ de propagation en relation avec la diversité de polarisation. De plus, l'utilisation d'ondes bi-polarisées permet l'amélioration d'une capacité de transmission via la réception simultanée de deux canaux orthogonaux. Cette thèse montre comment proposer et exploiter le concept très original de la diversité de polarisation sur la bande de fréquences mmW qui a été assignée aux applications sans fil. Auparavant, la diversité de polarisation était mise en oeuvre dans des profils non planaires, ce qui compliquait son intégration avec l'application de carte de circuit imprimé (PCB). Par conséquent, la motivation principale de cette thèse est de mettre en oeuvre la diversité de polarisation dans les profils planaires aux bandes de fréquence récemment assignées autour de 28 GHz et 38 GHz pour être intégrée dans la cinquième génération (5G) de communication sans fil. Ceci est fait en développant la théorie du fonctionnement et de la procédure de conception des composants MMW à double polarisation. La nouveauté présentée dans ce travail de thèse réside dans le développement d'un principe de fonctionnement permettant de concevoir et de mettre en évidence une classe de composants mmW bi-polarisés, à savoir les coupleurs 3dB, les coupleurs 0dB et les déphaseurs. Cela permet le développement de réseaux de formation de faisceau bi-polarisés tels que la matrice de Butler et les systèmes de télédétection à polarisation, basés sur une jonction à six ports à double polarisation. Une procédure de conception analytique complète est présentée avec des vérifications à travers des simulations pleine onde et des mesures de prototypes. La diversité de polarisation a été un facteur essentiel dans la performance et l'amélioration de la capacité de divers systèmes sans fil, y compris les réseaux cellulaires. Par conséquent, la conception et le développement de structures d'alimentation d'antenne bi-polarisées dans la bande mmW sont indispensables.----------ABSTRACT With the rapid and continuous development of new generation wireless technologies and networks such as 5G and with the limited enabling energy and spectrum resources available in support of such fast-moving wireless developments, exploring the underutilized millimeter-wave (mmW) bands becomes inescapable. It becomes more and more crucial to focus on the reduction of energy use in future wireless systems. The most efficient way of electromagnetic wave energy reception is to fully capture the two orthogonal components of its propagating field vector in connection with polarization diversity. In addition, the use of dually-polarized waves allows the enhancement of a transmission capability via the simultaneous reception of two orthogonal channels. This thesis shows how to propose and exploit the highly original concept of polarization diversity over the mmW frequency band which has been assigned for wireless applications. Previously, the polarization diversity was implemented within non-planar profiles which complicates its integration with the printed circuit board (PCB) application. Therefore, the main motivation of this thesis is to implement the polarization diversity within planar profiles at the recently assigned frequency bands around 28 GHz and 38 GHz to be suitable for integration in the fifth generation (5G) of wireless communication. This is done by developing the theory of operation and design procedure of dually-polarized mmW components. The novelty presented in this thesis work lies in developing a principle of operation to come up with the design and demonstration of a class of dually-polarized mmW components, namely 3dB couplers, 0dB couplers and phase shifters. This allows the development of dually-polarized beamforming networks such as Butler matrix and polarization-inclusive remote sensing systems based on a dually-polarized six-port junction. A full analytical design procedure is presented with verifications through full-wave simulations and prototype measurements. Polarization diversity has been an essential factor in the performance and capacity enhancement of various wireless systems including cellular networks. Accordingly, the design and development of dually-polarized antenna feeding structures in the mmW band is a must. Firstly, as the basic dual-polarized device, a compact orthomode transducer (OMT) design in the Ka-band is proposed. The novelty of the proposed OMT stems from a distinct concept of handling dually-polarized signals based on a polarization selective coupler (PSC)

Millimetre-wave power sensor design

This study is to maintain and extend the power standards at National Physical Laboratory (NPL) in the United Kingdom. The calibration service of microwave power sensors at high frequencies is endangered because a limited number of traceable waveguide power sensors is available at 50 GHz and above. In this thesis, the technologies of sensing microwave power in waveguides are reviewed, and the bolometric power sensor is investigated further, as its principle is suitable for the traceability requirement at NPL. The conventional design technique of bolometric sensor based on transmission line theory is generalised and two power sensor designs are introduced. The X-band sensor was fabricated, measured at the University of Birmingham and calibrated at NPL. Excellent linearity and high effective efficiency of the design was obtained. The high frequency power sensor designs based on the proposed technique can be scalable to 300 GHz and above, and a W-band sensor is introduced as an example. In order to add more flexibility in selecting frequency and bandwidth, a novel design of microwave power sensor with integrated filter function is described. An analytical power sensor synthesis technique using coupling matrix is presented for the first time. An X-band power sensor with integrated third order Chebyshev filter function was designed and manufactured. Experiential measurements in Birmingham and NPL are in good agreement with simulation and theoretical expectation

30 GHz Printed Ridge Gap Components and Antennas for Imaging Systems

Working at millimeter waves (MMW) has gained massive attention for wireless communications and imaging systems. For imaging systems, MMW can be used for security to provide good resolution images and detect concealed weapons as it can penetrate common clothes and reflect from the human body and metal objects. Moreover, MMW is safe for human health, contrary to conventional X-ray imaging, which uses an ionized wave. Thus, it has a harmful effect on human health. This research is focusing on building an active wide-view angle millimeter-wave imaging system with a small area of mechanical movement to reduce the data collection time. The imaging system is composed of three main parts: 1) the millimeter-wave components and antennas, 2) the mechanical part for moving the antennas and performing the scan of the imaging area, and 3) the imaging reconstruction algorithm. In order to have an efficient imaging system, the printed ridge gap technology (PRGW) is used to build the imaging system components and antennas. High efficiency coaxial to PRGW transition with a fractional bandwidth of 59.22% at 32.25 GHz is designed to feed the system components. For the transmitting part of the imaging system, a moderate gain PRGW differential feeding planar aperture antenna and a wideband rat-race coupler are designed. The antenna, the rat-race, and the coaxial transition are combined to form the transmitting part, then fabricated and measured. The resulted bandwidth is from 25.62 to 34.34 GHz with a return loss better than 10 dB, a maximum gain of 12.28 dBi, and 3-dB gain bandwidth from 25.62 to 33.77 GHz. For the receiving antenna, a PRGW Butler matrix and its components (directional couplers, 45◦ phase shifters, and crossovers) are designed. A semi-log periodic antenna fed by the PRGW is designed as the radiating element. The PRGW components, the coaxial transition, and the antennas are combined to form the receiving part of the imaging system, which is fabricated and measured. The resulting beam directions are at ±13◦ and ±36◦, at the center frequency (30 GHz). The return loss and the isolations are better than 10 dB over the frequency range from 26.1 to 33.5 GHz. For the imaging reconstruction algorithm, a synthetic aperture radar algorithm is used. Two tests are carried out, one uses CST simulation results, and the other uses measured data from the Concordia antenna chamber lab. The results show an output resolution of 0.6 λ. Finally, the whole imaging system is built with the designed differential feeding antenna as the transmitter, the designed Butler matrix as the receiver, and the synthetic aperture algorithm as the image reconstruction algorithm. The performance network analyzer (PNA) is used to collect the data (s-parameters) required to reconstruct the image, and the antenna range controller system (NSI 5913) is used to mechanically scan the imaging area. The imaging system is used to scan a mannequin carrying an object shaped like a pistol and a knife. The results show that the two objects are detected

The Telecommunications and Data Acquisition Report

In space communications, radio navigation, radio science, and ground based radio and radar astronomy, activities of the Deep Space Network and its associated Ground Communications Facility in planning, in supporting research and technology, in implementation, and in operations are reported. Also included is TDA funded activity at JPL on data and information systems and reimbursable DSN work performed for other space agencies through NASA

Six-Port Reflectometer in WR15 Metallic Waveguide for Free-Space Sensing Applications

International audienceThis work describes the design, fabrication and measurements of a six-port reflectometer in metallic waveguide technology for operation around 60 GHz. The system integration is based on WR15 building blocks. An in-situ linearization of the detectors associated to a vector calibration procedure is provided to determine the calibrated IQ components from the measured voltages. Near-field free-space distance measurements from contact to stand-off distance of two free-space wavelengths are shown to validate the technique proposed