The reflectarray antenna has been considered as a suitable candidate to replace the traditional parabolic reflectors because of its high-gain and low-profile features. Beam scanning capability and multi-band operation are the current trends of the reflectarray design. It is desired to implement these functionalities with simple and effective techniques. Narrow bandwidth is the main issue which restricts the applications of the microstrip antennas. New microstrip slot antennas and polarization diversified planar antennas are introduced as the solutions to the issue of narrow bandwidth in this dissertation. A dual-band beam scanning reflectarray has been developed. It is the first offset-fed reflectarray that has been ever practically developed to emulate a cylindrical/parabolic type of reflector. Unlike other beam scanning reflectarrays which integrate phase tuning devices into the reflectarray elements and control the reflection phase, the beam scanning capability of this reflectarray is provided by its feed array. This method significantly reduces the complexity of the design of the beam scanning reflectarray. A new dual-band reflectarray configuration is also developed to eliminate the possible top layer blocking effects in the dual-layer reflectarray configuration. Perforated patches loaded with slots on the ground plane and rectangular patches loaded with slots on the patches are adopted as the low and high frequency bands, respectively. It is guaranteed that no physical contact between any two elements will occur. The bandwidth of the conventional microstrip antenna is small. A new wideband circularly polarized microstrip slot antenna is introduced in this dissertation. Very wide 3-dB axial ratio bandwidth is observed for the proposed antenna. The antennas are assembled in triangularly arranged array with sequential rotation feed technique. Polarization polarity is an alternative solution to the narrow bandwidth. A reconfigurable circularly polarized microstrip antenna is proposed. The antenna has both right-hand and left-hand circular polarizations which are controlled by two piezoelectric transducers. In addition, a dual-band dual-linearly-polarized planar array is designed based on the concepts of polarization diversity and multi-band operation. The research presented in this dissertation suggests useful techniques for reflectarrays and novel antenna designs. The results should have many applications for the modern wireless communication and radar systems.

International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada / A major factor in the performance of a Telemetry System over the sea is the effect of multipath. The reflected signal from the surface of the sea may, in general, add to or subtract from the direct signal, and may therefore lead to severe fading and possible loss of useful signal. The multipath is a function of the sea state and the polarization of the signal. In order to reduce the effect of multipath on performance, a dual polarization diversity system is being built for the Airborne Telemetry Relay System for the Gulf Range. An analysis of the performance of the dual polarization diversity system in the presence of multipath for different sea states, different reflection angles, and different initial polarization angles is presented. For comparison, a similar analysis is presented for a circular polarization receiving antenna system.

International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / Telemetry receiving sites at missile test ranges almost always use polarization diversity to maximize the quality of the telemetry signals collected from missiles during developmental tests. If the sites are operating optimally, their sensitivity should be independent of received polarization. In this paper a technique to test the sensitivity of each receiving site is presented that involves radiating from a central location with selectable polarization and precise power level. Results of testing five telemetry sites are presented and compared with performance predicted through link analysis using site G/T and location information.

ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / A method for combining telemetry data and quantifying the resulting coding gain for a ballistic missile test flight is presented. Data received from five ground stations in 54 data files with 18 million intermittent frames is combined, to create a single file with 1.5 million continuous frames. Coding gain provided by data combining is as high as 30 dB, with a useful improvement of 5 dB at boost and terminal stages. With frame reconstruction techniques, erroneous words in a frame are reduced from 2.1% to 0.12 %.

yes / This paper presents a compact-size, low-cost smart antenna with electronically switchable radiation patterns, and reconfigurable polarizations. This antenna can be dynamically switched to realize three different polarizations including two orthogonal linear polarizations and one diagonally linear polarization. By closely placing several electronically reconfigurable parasitic elements around the driven antenna, the beam switching can be achieved in any of the three polarization states. In this design, a polarization reconfigurable square patch antenna with a simple feeding network is used as the driven element. The parasitic element is composed of a printed dipole with a PIN diode. Using different combinations of PIN diode ON/OFF states, the radiation pattern can be switched toward different directions to cover an angle range of 0◦ to 360◦ in the azimuth plane. The concept is confirmed by a series of measurements. This smart antenna has the advantages of compact size, low cost, low power consumption, reconfigurable polarizations, and beams.

International Telemetering Conference Proceedings / October 13-16, 1986 / Riviera Hotel, Las Vegas, Nevada / Predetection recording of spread-spectrum (SS) signals such as GPS transmissions is a desirable objective for both users and developers of equipment designed to receive such signals. (GPS user-equipment development is a lengthy process during which signal simulators are only partially useful.) Upon playback, GPS signals are used by the same or modified receivers so that acquisition, processing, detection and tracking loops can be altered to optimize the receiver parameters. Development of predetect SS signal recording systems is difficult to achieve in practice. Such systems not only must be of suitable phase linearity to preserve the signal content to be extracted but sometimes must also preserve the exact signal-to-noise ratio (SNR) characteristics of the recorded signals. Existing conventional test equipment is unsuitable for deriving value judgments of the quality of a predetect recording system’s output because the SS signal has a negative SNR. This paper reveals that it is possible to use, for this purpose, tape recorders now available on many test ranges in combination with auxiliary equipment similar to that designed for the U.S. Navy’s TRIDENT Program (recording C/A-code data from in-flight missile translators). The basic techniques are described in some detail to enable potential users to understand the necessary equipment concepts and evaluate the author’s approach in terms of their own applications.

This thesis deals with dual-polarized multiple input multiple output (MIMO) channels, an important issue for the practical deployment of multiple antenna systems. The MIMO architecture has the potential to dramatically improve the performance of wireless systems. Much of the focus of research has been on uni-polarized spatial MIMO configurations, the performance of which, is a strong function of the inter-element spacing. Thus the current trend of miniaturization, seems to be at odds with the implementation of spatial configurations in portable handheld devices. In this regard, dual-polarized antennas present an attractive alternative for realizing higher order MIMO architectures in compact devices. Unlike spatial channels, in the presence of polarization diversity, the subchannels of the MIMO channel matrix are not identically distributed. They differ in terms of average received power, envelope distributions, and correlation properties. In this thesis, we report on an indoor channel measurement campaign conducted at 2.4 GHz, to measure the copolarized and cross-polarized subchannels, under line-of-sight (LOS) and non-line-of-sight (NLOS) channel conditions. The measured data is then analyzed, to draw a fair comparison between spatial and dual-polarized MIMO systems, in terms of channel characteristics and achievable capacity. The main drawback of the MIMO architecture is that the gain in capacity comes at a cost of increased hardware complexity. Antenna selection is a technique using which we can alleviate this cost. We emphasize that this strategy is all the more relevant for compact devices, which are often constrained by complexity, power and cost. Using theoretical analysis and measurement results, this thesis investigates the performance of antenna selection in dual-polarized MIMO channels. Our results indicate that, antenna selection when combined with dual-polarized antennas, is an effective, low-complexity solution to the problem of realizing higher order MIMO architectures in compact devices.

Cette thèse s'inscrit dans le cadre du projet collaboratif FUI RFID AERO dont le leader est Eurocopter. Le but de ce projet est le développement d'un système assurant la traçabilité des différentes pièces d'un aéronef. Cette thèse se focalise sur la conception d'antennes lecteur et de tags RFID UHF faible coût.Deux objectifs sont visés dans le cadre de cette thèse. Le premier est la conception d'antennes pour lecteurs RFID fonctionnant en contact ou à proximité des surfaces métalliques. Nos conceptions sont basées d'une part sur les phénomènes d'ondes constructives en plaçant une surface métallique à un quart de la longueur d'onde. D'une autre part, la conception repose sur l'utilisation de structures AMC. De plus, nous proposons une méthode de réduction de dimensions de cellules AMC. Le second objectif de la thèse est la miniaturisation de tags pour l'identification de pièces essentiellement métalliques. Nous proposons des méthodes de conception de tags miniatures durcis, non détachables ou flexibles ainsi qu'un prototype pour chacune d'entre elles.Enfin, les antennes lecteur et tags développés dans cette thèse, les lecteurs RFID et des systèmes connexes développées par d'autres partenaires ont été mis en œuvre dans un aéronef. Les tests du système complet sont satisfaisants et répond aux objectifs du projet. / This Ph.D thesis is part of the FUI RFID AERO project led by Eurocopter. The aim of this project is to provide a traceability system of the aircraft items. This work focuses on low-cost UHF RFID reader antennas and tags design.Two research axes are developed. The first one is the RFID reader antennas design for metallic surfaces. The designs are based on constructive wave phenomenon by placing a metallic plate at a quarter wavelength of the radiating element. On the other hand, the insertion of AMC structures was also studied. Furthermore, we propose a size reduction technique for AMC structures. The second goal is tag size miniaturization for metallic or non-metallic objects identification. We propose design methods of size miniaturization for hard or flexible tags. Besides, we apply these methods by designing one tag for each family.Finally, the reader antennas and tags proposed in this thesis, the RFID readers and the related systems developed by the others partners were implemented into an aircraft. Tests of the complete system are in good agreement with the expected goals.

Les travaux présentés dans ce manuscrit sont relatifs à la conception et au développement d’antennes basées sur les structures artificielles – métamatériaux. La première antenne conçue et réalisée est une antenne bi-fonction en bande L (~1GHz) (GPS et DME) à diversité de bande/de polarisation, destinée aux applications aéronautiques. Ces travaux rentrent dans le cadre du projet MSIE (pôle de compétitivité ASTHEC) pour lequel notre LEME a été très actif. Les partenaires industriels de ce projet sont EADS/IW, Dassault aviation, INEO-Défense, SATIMO. Les résultats montrent la faisabilité d’une antenne unique pouvant avoir simultanément deux fonctions avec une diversité de polarisation et de bande spectrale. L’utilisation des métamatériaux a permis en particulier le maintien de la polarisation circulaire de l’antenne GPS -L1 à L5. La fonction DME a été consolidée avec le maintien de son gain. La seconde antenne est une antenne cavité Fabry-Pérot mettant en œuvre une structure partiellement réfléchissante double couche. Nous avons démontré le phénomène physique d’inversion de la phase du coefficient de réflexion de la PRS. Nous avons obtenu un gradient positif de phase sur une bande de 5 GHz autour de 80GHz. Grace à ce profil nouveau de la phase obtenu par la structure métamatériau PRS, on dispose d’une avance linéaire de la phase qui compense le retard du à la cavité Fabry-Pérot. Ainsi on maintient les conditions de résonance de la cavité sur une large bande, 5GHz. Nous démontrons, que la mise en œuvre de cette structure aux caractéristiques inédites permet de réaliser une antenne cavité ultra-directive sur une très large bande spectrale de 5GHz. Les performances atteintes sont une directivité de 35 à 40dBi sur 5 GHz, une adaptation parfaite (gain ~ directivité) avec très peu de sources primaires. L’antenne est compacte avec une hauteur totale inférieure au 10mm (connecteur compris) et une surface de 100mmx100mm. / The work presented in this manuscript is related to the design and development of antennas based on artificial structures - metamaterials. The first designed and built antenna is a GPS and DME dual-function in the L (~ 1GHz). It is an antenna designed with polarization and spectral diversities for aeronautical applications. The work is within the MSIE project of ASTHEC cluster for which our laboratory (LEME) was very active. The industrial partners of the project are EADS/IW, Dassault Aviation, INEO-Defense SATIMO. The results show the feasibility of a single antenna having simultaneously two functions with a diversity of polarization and spectral band. The use of metamaterials enabled in particular the preservation of circular polarization of the GPS antenna on the bands ranging from L1 to L2. The DME function was consolidated with the same gain.The second antenna is an antenna Fabry-Perot cavity employing a partially reflective structure (PRS) Double-layer. We have demonstrated by numerical simulation and experimental characterization, the physical phenomenon of inversion phase of the reflection coefficient PRS. We obtain a positive gradient of the phase over a broad band of 5 GHz around 80GHz. Thanks to this new profile obtained by the PRS metamaterial structure, it has a linear advance of the phase which compensates for the delay of the Fabry-Perot cavity. Thus the cavity resonance conditions are maintained over a wide band, 5GHz. We demonstrate that the implementation of this structure with unique features allows a highly directive antenna cavity over a very wide spectral band 5GHz. The performance are a directivity of 35-40 dBi over 5 GHz, a perfect adaptation (gain ~ directivity) with very few primary sources.

Machine-to-machine (M2M) communication is becoming an important aspect of warehouse management, remote control, robotics, traffic control, supply chain management, fleet management and telemedicine. M2M is expected to become a significant portion of the Industrial Internet and, more broadly, the Internet of Things (IoT). The environments in which M2M systems are expected to operate may be challenging in terms of radio wave propagation due to their cluttered, multipath nature, which can cause deep signal fades and signal depolarization. Polarization diversity in two dimensions is a well-known technique to mitigate such fades. But in the presence of reflectors and retarders where multipath components arrive from any direction, we find the detrimental effects to be three-dimensional and thus consider herein mitigation approaches that are also 3D. The objectives of this dissertation are three. First, to provide a theoretical framework for depolarization in three dimensions. Second, to prepare a tripolar antenna design that meets cost, power consumption, and simplicity requirements of M2M applications and that can mitigate the expected channel effects. Finally, to develop new channel models in three dimensional space for wireless systems. Accordingly, this dissertation presents a complete description of 3D electromagnetic fields, in terms of their polarization characteristics and confirms the advantage of employing tripolar antennas in multipath conditions. Furthermore, the experimental results illustrate that highly variable depolarization occurs across all three spatial dimensions and is dependent on small changes in frequency and space. Motivated by these empirical results, we worked with a collaborating institution to develop a three-dimensional tripolar antenna that can be integrated with a commercially available wireless sensor. This dissertation presents the testing results that show that this design significantly improves channels over traditional 2D approaches. The implications of tripolar antenna integration on M2M systems include reduction in energy use, longer wireless communication link distances, and/or greater link reliability. Similar results are shown for a planar antenna design that enables four different polarization configurations. Finally, the work presents a novel three-dimensional geometry-based stochastic channel model that builds the channel as a sum of shell-like sub-regions, where each sub-region consists of groups of multipath components. The model is validated with empirical data to show the approach may be used for system analyses in indoor environments.