Planar Lens Antenna for High Data Rate Applications

[EN] A low-profile lens antenna formed by 2 metallic rings with strips short-circuiting both rings is presented. The theory of characteristic modes is used to facilitate the design, optimization, and analysis of the structure. Simulations and measurements are presented for the optimized single-layer metallic lens antenna. Measured results show a large operating bandwidth (14.7% relative -14 dB impedance bandwidth) with a maximum directivity above 13.70 dBi and a return loss better than 14 dBThis work has been supported by the Spanish Ministry of Science, Innovation and Universities (Ministerio Ciencia, Innovacion y Universidades) under the projects TEC2016-79700-C2-1-Rand TEC2016-78028-C3-3-P and college scholarship graduate of the National University of ChimborazoSantillan-Haro, D.; Sánchez-Escuderos, D.; Antonino Daviu, E.; Ferrando Bataller, M. (2019). Planar Lens Antenna for High Data Rate Applications. Wireless Communications and Mobile Computing. 1-7. https://doi.org/10.1155/2019/5125287S17Mao, Y., You, C., Zhang, J., Huang, K., & Letaief, K. B. (2017). A Survey on Mobile Edge Computing: The Communication Perspective. IEEE Communications Surveys & Tutorials, 19(4), 2322-2358. doi:10.1109/comst.2017.2745201Jiang, M., Chen, Z. N., Zhang, Y., Hong, W., & Xuan, X. (2017). Metamaterial-Based Thin Planar Lens Antenna for Spatial Beamforming and Multibeam Massive MIMO. IEEE Transactions on Antennas and Propagation, 65(2), 464-472. doi:10.1109/tap.2016.2631589Garbacz, R., & Turpin, R. (1971). A generalized expansion for radiated and scattered fields. IEEE Transactions on Antennas and Propagation, 19(3), 348-358. doi:10.1109/tap.1971.1139935Harrington, R., & Mautz, J. (1971). Theory of characteristic modes for conducting bodies. IEEE Transactions on Antennas and Propagation, 19(5), 622-628. doi:10.1109/tap.1971.1139999Miers, Z., & Lau, B. K. (2015). Wideband Characteristic Mode Tracking Utilizing Far-Field Patterns. IEEE Antennas and Wireless Propagation Letters, 14, 1658-1661. doi:10.1109/lawp.2015.2417351Antonino-Daviu, E., Cabedo-Fabres, M., Sonkki, M., Mohamed Mohamed-Hicho, N., & Ferrando-Bataller, M. (2016). Design Guidelines for the Excitation of Characteristic Modes in Slotted Planar Structures. IEEE Transactions on Antennas and Propagation, 64(12), 5020-5029. doi:10.1109/tap.2016.2618478Capek, M., Hazdra, P., Masek, M., & Losenicky, V. (2017). Analytical Representation of Characteristic Mode Decomposition. IEEE Transactions on Antennas and Propagation, 65(2), 713-720. doi:10.1109/tap.2016.2632725Yang, X., Liu, Y., & Gong, S.-X. (2018). Design of a Wideband Omnidirectional Antenna With Characteristic Mode Analysis. IEEE Antennas and Wireless Propagation Letters, 17(6), 993-997. doi:10.1109/lawp.2018.2828883Santillán-Haro, D., Antonino-Daviu, E., Sánchez-Escuderos, D., & Ferrando-Bataller, M. (2018). Analysis and Design of a Metamaterial Lens Antenna Using the Theory of Characteristic Modes. International Journal of Antennas and Propagation, 2018, 1-8. doi:10.1155/2018/6329531Karimkashi, S., & Kishk, A. A. (2011). Focusing Properties of Fresnel Zone Plate Lens Antennas in the Near-Field Region. IEEE Transactions on Antennas and Propagation, 59(5), 1481-1487. doi:10.1109/tap.2011.212306

Small Footprint Multilayered Millimeter-Wave Antennas and Feeding Networks for Multi-Dimensional Scanning and High-Density Integrated Systems

This paper overviews the state-of-the-art of substrate integrated waveguide (SIW) techniques in the design and realization of innovative low-cost, low-profile and low-loss (L3) millimeter-wave antenna elements, feeding networks and arrays for various wireless applications. Novel classes of multilayered antenna structures and systems are proposed and studied to exploit the vertical dimension of planar structures to overcome certain limita-tions in standard two-dimensional (2-D) topologies. The developed structures are based on two techniques, namely multi-layer stacked structures and E-plane corners. Differ-ent E-plane structures realised with SIW waveguide are presented, thereby demonstrating the potential of the proposed techniques as in multi-polarization antenna feeding. An array of 128 elements shows low SLL and height gain with just 200g of the total weight. Two versions of 2-D scanning multi-beam are presented, which effectively combine frequency scanning with beam forming networks. Adding the benefits of wide band performance to the multilayer structure, two bi-layer structures are investigated. Different stacked antennas and arrays are demonstrated to optimise the targeted antenna performances in the smallest footprint possible. These structures meet the requirement for developing inexpensive compact millimeter-wave antennas and antenna systems. Different structures and architectures are theoretically and experimentally studied and discussed for specific space- and ground-based appli-cations. Practical issues such as high-density integration and high-volume manufacturability are also addressed

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Cílem disertační práce je navrhnout efektivně pracující algoritmus, který na základě bezfázového měření v blízkém poli antény bude schopen zrekonstruovat komplexní blízké pole antény resp. vyzařovací diagram antény ve vzdáleném poli. Na základě těchto úvah byly zkoumány vlastnosti minimalizačního algoritmu. Zejména byl analyzován a vhodně zvolen minimalizační přistup, optimalizační metoda a v neposlední řadě i optimalizační funkce tzv. funkcionál. Dále pro urychlení celého minimalizačního procesu byly uvažovány prvotní odhady. A na závěr byla do minimalizačního algoritmu zahrnuta myšlenka nahrazující hledané elektrické pole několika koeficienty. Na základě předchozích analýz byla navržená bezfázová metoda pro charakterizaci vyzařovacích vlastností antén. Tato metoda kombinuje globální optimalizaci s obrazovou kompresní metodou a s lokální metodou ve spojení s konvečním amplitudovým měřením na dvou površích. V našem případě je globální optimalizace použita k nalezení globálního minima minimalizovaného funkcionálu, kompresní metoda k redukci neznámých proměnných na apertuře antény a lokální metoda zajišťuje přesnější nalezení minima. Navržená metoda je velmi robustní a mnohem rychlejší než jiné dostupné minimalizační algoritmy. Další výzkum byl zaměřen na možnosti využití měřených amplitud pouze z jednoho měřícího povrchu pro rekonstrukci vyzařovacích charakteristik antén a využití nového algoritmu pro rekonstrukci fáze na válcové geometrii.The aim of this dissertation thesis is to design a very effective algorithm, which is able to reconstruct the antenna near-field and radiation patterns, respectively, from amplitude-only measurements. Under these circumstances, the properties of minimization algorithm were researched. The selection of the minimization approach, optimization technique and the appropriate functional were investigated and appropriately chosen. To reveal the global minimum area faster, the possibilities in the form of initial estimates for accelerating minimization algorithm were also considered. And finally, the idea to represent the unknown electric field distribution by a few coefficients was implicated into the minimization algorithm. The designed near-field phaseless approach for the antenna far-field characterization combines a global optimization, an image compression method and a local optimization in conjunction with conventional two-surface amplitude measurements. The global optimization method is used to minimize the functional, the image compression method is used to reduce the number of unknown variables, and the local optimization method is used to improve the estimate achieved by the previous method. The proposed algorithm is very robust and faster than comparable algorithms available. Other investigations were focused on possibilities of using amplitude from only single scanning surface for reconstruction of radiation patterns and the application of the novel phase retrieval algorithm for cylindrical geometry.

A new low profile antenna with improved performance for satellite on-the-move communications

A novel design solution for a low-profile fullduplex Satellite-On-The-Move Communications hybrid scanned phased array antenna for low elevation angle coverage (down to 10°) is described. The antenna is operated at Ku-Band. The unique louvered array element geometry in combination with a spatial filter/ “ray bending” lens facilitates the shaping of the element pattern to increase gain at low elevation angles. Preliminary modelling results using simple ray-tracing and 3D E simulation indicate that the desired low angle coverage can be achieved

Stretchable electronic platform for soft and smart contact lens applications

A stretchable platform with spherical-shaped electronics based on thermo- plastic polyurethane (TPU) is introduced for soft smart contact lenses. The low glass transition temperature of TPU, its relatively low hardness, and its proven biocompatibility (i.e., protection of exterior body wounds) fulfill the essential requirements for eye wearable devices. These requirements include optical transparency, conformal fitting, and flexibility comparable with soft contact lenses (e.g., hydrogel-based). Moreover, the viscoelastic nature of TPU allows planar structures to be thermoformed into spherical caps with a well-defined curvature (i.e., eye’s curvature at the cornea: 9 mm). Numerical modeling and experimental validation enable fine-tuning of the thermo - forming parameters and the optimization of strain-release patterns. Such tight control is proven necessary to achieve oxygen permeable, thin, nonde- velopable, and wrinkle-free contact lenses with integrated electronics (silicon die, radio-frequency antenna, and stretchable thin-film interconnections). This work paves the way toward fully autonomous smart contact lenses potentially for vision correction or sensing applications, among others

Orbital Angular Momentum Waves: Generation, Detection and Emerging Applications

Orbital angular momentum (OAM) has aroused a widespread interest in many fields, especially in telecommunications due to its potential for unleashing new capacity in the severely congested spectrum of commercial communication systems. Beams carrying OAM have a helical phase front and a field strength with a singularity along the axial center, which can be used for information transmission, imaging and particle manipulation. The number of orthogonal OAM modes in a single beam is theoretically infinite and each mode is an element of a complete orthogonal basis that can be employed for multiplexing different signals, thus greatly improving the spectrum efficiency. In this paper, we comprehensively summarize and compare the methods for generation and detection of optical OAM, radio OAM and acoustic OAM. Then, we represent the applications and technical challenges of OAM in communications, including free-space optical communications, optical fiber communications, radio communications and acoustic communications. To complete our survey, we also discuss the state of art of particle manipulation and target imaging with OAM beams

Deployable antenna demonstration project

Test program options are described for large lightweight deployable antennas for space communications, radar and radiometry systems