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1. Iterative Interference Cancellation for Time Reversal Division Multiple Access

Author

Ali Mokh, George C. Alexandropoulos, Mohamed Kamoun, Abdelwaheb Ourir, Arnaud Tourin, Mathias Fink, and Julien de Rosny

Subjects
Time reversal, interference, multiple access, ultra-wideband, precoding, experiments, Electrical engineering. Electronics. Nuclear engineering, TK1-9971
Abstract

Time Reversal (TR) has been proposed as a competitive precoding strategy for low-complexity devices, relying on ultra-wideband waveforms. This transmit processing paradigm can address the need for low power and low complexity receivers, which is particularly important for the Internet of Things, since it shifts most of the communications signal processing complexity to the transmitter side. Due to its spatio-temporal focusing property, TR has also been used to design multiple access schemes for multi-user communications scenarios. However, in wideband time-division multiple access schemes, the signals received by users suffer from significant levels of inter-symbol interference as well as interference from uncoordinated users, which often require additional processing at the receiver side. This paper proposes an iterative TR scheme that aims to reduce the level of interference in wideband multi-user settings, while keeping the processing complexity only at the transmitter side. The performance of the proposed TR-based protocol is evaluated using analytical derivations. In addition, its superiority over the conventional Time Reversal Division Multiple Access (TRDMA) scheme is demonstrated through simulations as well as experimental measurements at 2.5 GHz carrier frequency with variable bandwidth values.

Published
2023
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2. Electromagnetically Induced Transparency in Symmetric Planar Metamaterial at THz Wavelengths

Author

Abdelwaheb Ourir, Bruno Gallas, Loic Becerra, Julien de Rosny, and Pierre Richard Dahoo

Subjects
metamaterial, induced transparency, slow light, infrared, Applied optics. Photonics, TA1501-1820
Abstract

We report the experimental observation and the evidence of the analogue of electromagnetically-induced transparency (EIT) in a symmetric planar metamaterial. This effect has been obtained in the THz range thanks to a destructive Fano-interference between the two first modes of an array of multi-gap split ring resonators deposited on a silicon substrate. This structure is a planar thin film material with four-fold symmetry. Thanks to this property, a polarization-independent transmission has been achieved. The proposed metamaterial is well adapted to variety of slow-light applications in the infrared and optical range.

Published
2015
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15. Single-Carrier Spatial Modulation for the Internet of Things: Design and Performance Evaluation by Using Real Compact and Reconfigurable Antennas.

Author

Dinh Thuy Phan Huy, Yvan Kokar, Kammel Rachedi, Patrice Pajusco, Ali Mokh, Theoni Magounaki, R. Masood, Cyril Buey, Philippe Ratajczak, Nadine Malhouroux-Gaffet, Jean-Marc Conrat, Jean-Christophe Prévotet, Abdelwaheb Ourir, Julien de Rosny, Matthieu Crussière, Maryline Hélard, Azeddine Gati, Thierry Sarrebourse, and Marco Di Renzo

Published
2019
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20. TIME-REVERSAL OF SUB-THZ PULSES IN COMPLEX MEDIA

Author

Ali Mokh, Ramin Khayatzadeh, Abdelwaheb Ourir, Mohamed Kamoun, Arnaud Tourin, Mathias Fink, and Julien de Rosny

Subjects
Electrical and Electronic Engineering, Condensed Matter Physics, Electronic, Optical and Magnetic Materials
Published
2022
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21. Open birdcage coil for head imaging at 7T

Author

Nikolai I. Avdievich, A. Nikulin, Abdelwaheb Ourir, Alexandre Vignaud, D. Berrahou, Julien de Rosny, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), High-Field MR Center, Max Planck Institute for Biological Cybernetics, and Multiwave Imaging

Subjects
ultra-high-field MRI, Acoustics, brain imaging, Tracking (particle physics), Imaging phantom, 030218 nuclear medicine & medical imaging, head coil, 03 medical and health sciences, 0302 clinical medicine, Humans, Radiology, Nuclear Medicine and imaging, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Physics, open coil, Phantoms, Imaging, Homogeneity (statistics), Brain, Specific absorption rate, Equipment Design, Magnetic Resonance Imaging, Transfer matrix, Symmetry (physics), Magnetic field, birdcage coil, Electromagnetic coil, Head, 030217 neurology & neurosurgery
Abstract

Purpose: To theoretically describe, design, and test the new geometry of the birdcage coil for 7 Tesla anatomical brain imaging, which includes a large window on top, without deliberately jeopardizing its homogeneity and efficiency. This opencage will not only improve patient comfort but also enable the volunteer to follow functional MRI stimuli. This design could also facilitate the tracking of patient compliance and enable better correction of the movement. Methods: Via the transfer matrix approach, a birdcage-like coil with a nonperiodic distribution of rungs is constructed with optimized currents in the coil rungs. Subsequently, the coil is adjusted in full-wave simulations. Then, the coil is assembled, fine-tuned, and matched on the bench. Finally, these results are confirmed experimentally on a phantom and in vivo. Results: Indeed, the computed isolation of -14.9 dB between the feeding ports of the coil and the symmetry of the circular polarized mode pattern transmit RF magnetic field ( B+1 ) showed that the coil was properly optimized. An experimental assessment of the developed coil showed competitive transmit efficiency and coverage compared with the conventional birdcage coil of similar size. Conclusion: The proposed opencage coil can be designed and work without a dramatic drop of performance in terms of the B+1 field homogeneity, transmit efficiency ( (B+1) / √Pref ), peak local specific absorption rate ( SAR10g ) and SAR efficiency ( (B+1) / √SAR10g ).

Published
2021
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22. Polarization-Based Reconfigurable Tags for Robust Ambient Backscatter Communications

Author

M. Di Renzo, Y. Kokar, Abdelwaheb Ourir, Dinh-Thuy Phan-Huy, R. Fara, J. de Rosny, Jean-Christophe Prévotet, Maryline Helard, Orange Labs, Laboratoire des signaux et systèmes (L2S), CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL), Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), This work was supported by the French Project ANR Spatial Modulation under Grant ANR-15-CE25-0016 (https://spatialmodulation.eurestools.eu/)., ANR-15-CE25-0016,SpatialModulation,modulation spatiale et antenne reconfigurable pour connecter en haut débit des capteurs mobiles et autonomes en énergie(2015), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA), and Université de Nantes (UN)-Université de Rennes 1 (UR1)

Subjects
Signal Processing (eess.SP), ambient backscatter communication, Backscatter, Computer science, Internet of Things, Binary number, 02 engineering and technology, Dipole antennas, 01 natural sciences, lcsh:Telecommunication, law.invention, Radio frequency signal, Robustness (computer science), law, lcsh:TK5101-6720, 0103 physical sciences, FOS: Electrical engineering, electronic engineering, information engineering, Electronic engineering, Electrical Engineering and Systems Science - Signal Processing, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], 010302 applied physics, Reconfigurable antenna, Detector, Detectors, Computer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing), Antenna radiation patterns, 021001 nanoscience & nanotechnology, Polarization (waves), lcsh:HE1-9990, compact reconfigurable antennas, Encoding, lcsh:Transportation and communications, Interference, 0210 nano-technology, Radio wave
Abstract

Ambient backscatter communication is an emerging and promising low-energy technology for the Internet of Things. In such a system, a tag sends a binary message to a reader by backscattering a radio frequency signal generated by an ambient source. The tag can operate without battery and without generating additional radio waves. However, the tag-to-reader link suffers from the source-to-reader interference. In this paper, we propose a polarization-based reconfigurable antenna in order to improve the robustness of the tag-to-reader link against the source-to-reader direct interference. More precisely, we compare different types of tags' antennas, different tags' encoding schemes, and different detectors at the reader. By using analysis, numerical simulations, and experiments, we show that a polarization-based reconfigurable tag with four polarization directions significantly outperforms a non-reconfigurable tag, and provides almost the same performance as an ideal reconfigurable tag with a large number of reconfigurable polarization patterns., Comment: Published in IEEE Open Journal of the Communications Society (Volume: 1). arXiv admin note: text overlap with arXiv:2111.01917

Published
2020
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23. Reconfigurable intelligent surface-assisted ambient backscatter communications – Experimental assessment

Author

Philippe Ratajczak, Dinh-Thuy Phan-Huy, M. Di Renzo, J. de Rosny, Abdelwaheb Ourir, R. Fara, Université Paris-Saclay, Orange Labs Networks, Université Paris sciences et lettres (PSL), Laboratoire des signaux et systèmes (L2S), CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), and qian, xuewen

Subjects
Internet of things, Backscatter, Computer science, Ambient backscattering, Acoustics, Codebook, Metasurface, Energy consumption, Signal, [SPI.TRON] Engineering Sciences [physics]/Electronics, [SPI.TRON]Engineering Sciences [physics]/Electronics, Reconfigurable intelligent surface, Radio propagation, Surface wave, Reflection (physics), Network performance, 6G
Abstract

International audience; Sixth generation (6G) mobile networks may include new passive technologies, such as ambient backscatter communication or the use of reconfigurable intelligent surfaces, to avoid the emission of waves and the corresponding energy consumption. On the one hand, a reconfigurable intelligent surface improves the network performance by adding electronically controlled reflected paths in the radio propagation channel. On the other hand, in an ambient backscatter system, a device, named tag, communicates towards a reader by backscattering the waves of an ambient source (such as a TV tower). However, the tag's backscattered signal is weak and strongly interfered by the direct signal from the ambient source. In this paper, we propose a new reconfigurable intelligent surface assisted ambient backscatter system. The proposed surface allows to control the reflection of an incident wave coming from the exact source location towards the tag and reader locations (creating hot spots at their locations), thanks to passive reflected beams from a predefined codebook. A common phase-shift can also be applied to the beam. Thanks to these features, we demonstrate experimentally that the performance of ambient backscatter communications can be significantly improved.

Published
2021
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24. Robust Ambient Backscatter Communications with Polarization Reconfigurable Tags

Author

Dinh-Thuy Phan-Huy, Romain Fara, Julien de Rosny, M. Di Renzo, Abdelwaheb Ourir, and Orange Labs

Subjects
Signal Processing (eess.SP), Backscatter, business.industry, Scattering, Computer science, Electrical engineering, 020302 automobile design & engineering, 02 engineering and technology, Polarization (waves), Communications system, Radiation pattern, 0203 mechanical engineering, FOS: Electrical engineering, electronic engineering, information engineering, Electrical Engineering and Systems Science - Signal Processing, business, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]
Abstract

Ambient backscatter communication system is an emerging and promising low-energy technology for Internet of Things. In such system, a device named tag, sends a binary message to a reader by backscattering a radio frequency signal generated by an ambient source. Such tag can operate without battery and without generating additional wave. However, the tag-to-reader link suffers from the source-to-reader direct interference. In this paper, for the first time, we propose to exploit a "polarization reconfigurable" antenna to improve robustness of the tag-to-reader link against the source-to-reader direct interference. Our proposed new tag sends its message by backscattering as an usual tag. However, it repeats its message several times, with a different radiation pattern and polarization, each time. We expect one polarization pattern to be better detected by the reader. We show by simulations and experiments, in line-of-sight and in richly scattering environment, that a polarization reconfigurable tag limited to 4 polarization directions outperforms a nonreconfigurable tag and nearly equals an ideally reconfigurable tag in performance., Published in Proceedings 2020 IEEE 31st Annual International Symposium on Personal, Indoor and Mobile Radio Communications

Published
2020
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25. Experimental Realization of a Clinical Opencage Head Coil for Ultra-High Field MRI

Author

Anton Nikulin, Marc Dubois, Tania del Socorro VERGARA GOMEZ, Djamel Berrahou, Frank Kober, Alexandre Vignaud, Redha Abdeddaim, Julien Rosny, Abdelwaheb Ourir, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Centre de résonance magnétique biologique et médicale (CRMBM), Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Multiwave Imaging, Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)

Subjects
Quantitative Biology::Biomolecules, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Physics::Medical Physics
Abstract

International audience; A conventional birdcage head coil at 7T is not well suited for certain applications such as motion control. We propose an original coil based on a birdcage with a wide lateral aperture that provides access to the object under examination. We show that a sufficiently homogeneous magnetic field distribution can be obtained by optimizing the current distribution of such an "Opencage". That coil was optimized using a full wave simulation and tested experimentally. The performance of an Opencage coil was compared to a commercial birdcage coil. Eventually, the Opencage coil is shown as a tradeoff between field homogeneity and access.

Published
2020

26. Beam Steering Reconfigurable Compact Antenna Based on Hybridization between Split Ring Resonators

Author

Yvan Kokar, Abdelwaheb Ourir, Julien de Rosny, Kammel Rachedi, Dinh Thuy Phan Huy, Université Paris sciences et lettres (PSL), Institut Laue-Langevin (ILL), Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Orange Gardens, French Project ANR Spatial ModulationFrench National Research Agency (ANR) [ANR-15-CE25-0016], LABEX WIFI (Laboratory of Excellence within the French Program Investments for the Future) [ANR-10-LABX-24, ANR-10-IDEX-0001-02 PSL], ANR-15-CE25-0016,SpatialModulation,modulation spatiale et antenne reconfigurable pour connecter en haut débit des capteurs mobiles et autonomes en énergie(2015), ILL, Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Nantes Université (NU)-Université de Rennes 1 (UR1)

Subjects
Physics, business.industry, 020208 electrical & electronic engineering, Beam steering, 020206 networking & telecommunications, 02 engineering and technology, Condensed Matter Physics, 7. Clean energy, Electronic, Optical and Magnetic Materials, Split-ring resonator, Optics, 0202 electrical engineering, electronic engineering, information engineering, [CHIM]Chemical Sciences, Antenna (radio), business
Abstract

International audience; Reconfigurable antennas that are able to provide a high spatial diversity are increasingly adopted in many wireless applications. An original design of a planar printed compact antenna that achieves an electronically controlled beam steering by using metamaterial hybridization is presented in this paper. The designed antenna, made of coupled split ring resonators, is able to switch between 8 radiation patterns steering in 8 different directions at the working frequency of 2.45 GHz. The spatial diversity is assessed from the analysis of the correlation matrix between the patterns. This concept would provide a promising and compact solution for green telecommunication systems.

Published
2020
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27. First experimental ambient backscatter communication using a compact reconfigurable tag antenna

Author

M. Di Renzo, Jean-Christophe Prévotet, J. de Rosny, Dinh-Thuy Phan-Huy, Maryline Helard, Romain Fara, Abdelwaheb Ourir, Kammel Rachedi, Yvan Kokar, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Orange Labs [Chatillon], Orange Labs, Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), CentraleSupélec, Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut d'Electronique et de Télécommunications de Rennes (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Institut Langevin - Ondes et Images, Université Paris Diderot - Paris 7 (UPD7)-ESPCI ParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut Langevin ondes et images, Centre National de la Recherche Scientifique (CNRS)-ESPCI ParisTech-Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)

Subjects
Modulation order, Backscatter, business.industry, Computer science, Electrical engineering, Battery (vacuum tube), 020206 networking & telecommunications, 02 engineering and technology, Radiation, ACM: B.: Hardware/B.4: INPUT/OUTPUT AND DATA COMMUNICATIONS/B.4.1: Data Communications Devices/B.4.1.1: Receivers (e.g., voice, data, image), Dipole, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], ACM: B.: Hardware/B.4: INPUT/OUTPUT AND DATA COMMUNICATIONS/B.4.1: Data Communications Devices/B.4.1.2: Transmitters, ACM: C.: Computer Systems Organization/C.2: COMPUTER-COMMUNICATION NETWORKS/C.2.5: Local and Wide-Area Networks, 11. Sustainability, 0202 electrical engineering, electronic engineering, information engineering, Bit error rate, Radio frequency, Antenna (radio), business, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

International audience; Ambient backscatter communications have emerged as a promising technology for a sustainable development of the Internet of Things (IoT). In such system, a radio frequency (RF) tag can transmit data to a receiver without battery and without generating any new RF wave, just by backscattering the incident RF wave originated by an ambient RF source. The simplest tag is a dipole that is either in an absorbing mode or in reflecting mode to send "0" or "1", and thus leads to a modulation order of 2. Previous solutions to reach higher modulation order, so as to achieve higher data rate, are based on antenna arrays. However, such solutions are not suitable for connected objects, due to their sizes. In this paper, for the first time, we propose a new tag that uses a compact antenna with reconfigurable radiation patterns to provide a high modulation order. We present experimental bit error rate measurements obtained with an experimental test-bed and two tag antennas, both providing 4 states and thus being able to convey 2 bits per symbol. These measurements show that the performance improves with increasing number of receive antennas, and lead to the conclusion that a tag antenna with low cross-correlations between reconfigurable radiation patterns is suitable for backscattering applications in IoT.

Published
2019
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28. Enhancing surface coil sensitive volume with hybridized electric dipoles at 17.2 T

Author

Julien de Rosny, Tania S. Vergara Gomez, Frank Kober, Redha Abdeddaim, Stefan Enoch, Abdelwaheb Ourir, Camille Jouvaud, Marc Dubois, Luisa Ciobanu, Institut FRESNEL (FRESNEL), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Centre de résonance magnétique biologique et médicale (CRMBM), Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), CLARTE (CLARTE), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information (CEA-LETI), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut des Sciences du Vivant Frédéric JOLIOT (JOLIOT), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Service NEUROSPIN (NEUROSPIN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Electronique et des Technologies de l'Information (CEA-LETI), Université Grenoble Alpes (UGA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Université Grenoble Alpes (UGA), Institut Langevin - Ondes et Images, Université Paris Diderot - Paris 7 (UPD7)-ESPCI ParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA))

Subjects
Larmor precession, [PHYS]Physics [physics], Nuclear and High Energy Physics, Materials science, Field (physics), business.industry, Plane (geometry), Biophysics, Metamaterial, 010402 general chemistry, Condensed Matter Physics, 01 natural sciences, Biochemistry, Imaging phantom, 030218 nuclear medicine & medical imaging, 0104 chemical sciences, 03 medical and health sciences, Resonator, Electric dipole moment, 0302 clinical medicine, Optics, Signal-to-noise ratio (imaging), business
Abstract

International audience; Preclinical MR applications at 17.2 T can require field of views on the order of a few square centimeters. This is a challenging task as the proton Larmor frequency reaches 730 MHz. Most of the protocols at such frequencies are performed with surface transceiver coils for which the sensitive volume and the signal to noise ratio (SNR) is given by their size. Here we propose an approach based on metamaterials in order to enhance the sensitive volume of a commercial surface coil for small animal imaging at 17.2 T. We designed a passive resonator composed of four hybridized electric dipoles placed onto the floor of the MRI bed. Combining numerical and experimental results on a phantom and in vivo, we demonstrate a 20% increase of the sensitive volume in depth and 25% along the rostro-caudal axis while maintaining more than 85% of the local SNR right beneath the surface coil plane. Moreover, our solution gives the ability to double the average SNR in the region between 1.2 and 2 cm away from the loop using a single layer of 1 mm thick metallic wires easy to design and manufacture.

Published
2019
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29. Enhanced resonance of sparse arrays of Helmholtz resonators—Application to perfect absorption

Author

Jean-François Mercier, Agnès Maurel, and Abdelwaheb Ourir, Kim Pham, Jean-Jacques Marigo, Institut Laue-Langevin (ILL), ILL, École Nationale Supérieure de Techniques Avancées (ENSTA Paris), Institut Langevin ondes et images, Centre National de la Recherche Scientifique (CNRS)-ESPCI ParisTech-Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC), Ecole Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris-Sciences-et-Lettres (https://www.psl.eu/), Propagation des Ondes : Etude Mathématique et Simulation (POEMS), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Unité de Mathématiques Appliquées (UMA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la mécanique et Applications industrielles (IMSIA - UMR 9219), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay-EDF R&D (EDF R&D), EDF (EDF)-EDF (EDF), Laboratoire de mécanique des solides (LMS), École polytechnique (X)-MINES ParisTech - École nationale supérieure des mines de Paris-Centre National de la Recherche Scientifique (CNRS), École polytechnique (X), Institut Langevin - Ondes et Images, Université Paris Diderot - Paris 7 (UPD7)-ESPCI ParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Université Pierre et Marie Curie - Paris 6 (UPMC), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL), Propagation des Ondes : Étude Mathématique et Simulation (POEMS), École polytechnique (X)-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Paris Diderot - Paris 7 (UPD7)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Soprano, Service de Physique Théorique (SPhT), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Propagation des Ondes: Etude Mathématique et Simulation (POEMS-POST), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-EDF R&D (EDF R&D), École polytechnique (X)-Mines Paris - PSL (École nationale supérieure des mines de Paris), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Absorption (acoustics), Acoustics and Ultrasonics, Acoustics, [SPI.MECA.MSMECA]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Materials and structures in mechanics [physics.class-ph], 01 natural sciences, 010305 fluids & plasmas, Resonator, symbols.namesake, Arts and Humanities (miscellaneous), 0103 physical sciences, Radiative transfer, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, [SPI.MECA.SOLID]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Mechanics of the solides [physics.class-ph], Electrical impedance, ComputingMilieux_MISCELLANEOUS, [PHYS.MECA.VIBR]Physics [physics]/Mechanics [physics]/Vibrations [physics.class-ph], [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Physics, [PHYS]Physics [physics], Resonance, [PHYS.MECA]Physics [physics]/Mechanics [physics], [PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph], Helmholtz free energy, symbols, Acoustic impedance, Acoustic resonance
Abstract

International audience; We inspect the influence of the spacing on the resonance of a periodic arrangement of Helmholtz resonators. An effective problem is used which captures accurately the properties of the resonant array within a large range of frequency, and whose simplified version leaves us with an impedance condition. It is shown that the strength of the resonance is enhanced when the array becomes sparser. This degree of freedom on the radiative damping is of particular interest since it does not affect the resonance frequency nor the damping due to losses within each resonator; besides, it does not affect the total thickness of the array. We show that it can be used for the design of a perfect absorbing walls.

Published
2019
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30. Opencage radio frequency coil for magnetic resonance imaging

Author

J. de Rosny, Benoit Larrat, K. Haliot, A. Nikulin, Abdelwaheb Ourir, Laboratoire Ondes et Acoustique (UMR 7587) (LOA), Université Paris Diderot - Paris 7 (UPD7)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Unité d'imagerie par résonance magnétique à très haut champ et de spectroscopie (UNIRS), Service NEUROSPIN (NEUROSPIN), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010302 applied physics, Physics, Scanner, Physics and Astronomy (miscellaneous), medicine.diagnostic_test, Acoustics, Physics::Medical Physics, Impedance matching, Metamaterial, Magnetic resonance imaging, 02 engineering and technology, Iterative reconstruction, 021001 nanoscience & nanotechnology, 01 natural sciences, Amplitude, Region of interest, Electromagnetic coil, 0103 physical sciences, medicine, 0210 nano-technology, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]
Abstract

We present a volume radio frequency coil for Magnetic Resonance Imaging that provides access to the region of interest. While the conventional birdcage coil is composed of a periodic array of similar unit cells making a cylindrical structure, the proposed coil, called “opencage,” is made of an aperiodic array of metamaterial based unit cells presenting different geometries and characteristics. We develop here a dedicated approach based on Bloch impedance matching and phase balance for the design of the opencage coil. We perform full-wave numerical simulations to validate this concept. An experimental demonstration of the opencage coil for small animal imaging at 7 Tesla is presented. The results of the in-vitro, in-vivo imaging and B 1 + map reconstruction achieved with a preclinical MRI scanner are presented. We show that B 1 + field homogeneity and amplitude generated by the opencage coil are comparable to those of a conventional birdcage coil of the same size.We present a volume radio frequency coil for Magnetic Resonance Imaging that provides access to the region of interest. While the conventional birdcage coil is composed of a periodic array of similar unit cells making a cylindrical structure, the proposed coil, called “opencage,” is made of an aperiodic array of metamaterial based unit cells presenting different geometries and characteristics. We develop here a dedicated approach based on Bloch impedance matching and phase balance for the design of the opencage coil. We perform full-wave numerical simulations to validate this concept. An experimental demonstration of the opencage coil for small animal imaging at 7 Tesla is presented. The results of the in-vitro, in-vivo imaging and B 1 + map reconstruction achieved with a preclinical MRI scanner are presented. We show that B 1 + field homogeneity and amplitude generated by the opencage coil are comparable to those of a conventional birdcage coil of the same size.

Published
2019
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31. Single-Carrier Spatial Modulation for the Internet of Things: Design and Performance Evaluation by Using Real Compact and Reconfigurable Antennas

Author

J.-M. Conrat, T. Sarrebourse, Cyril Buey, Matthieu Crussiere, Jean-Christophe Prévotet, Dinh-Thuy Phan-Huy, Patrice Pajusco, Maryline Helard, Philippe Ratajczak, Rizwan Masood, M. Di Renzo, Kammel Rachedi, Ali Mokh, Nadine Malhouroux-Gaffet, Abdelwaheb Ourir, J. de Rosny, Y. Kokar, T. Magounaki, Azeddine Gati, Orange Labs, Institut d'Électronique et des Technologies du numéRique (IETR), Nantes Université (NU)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT), Lab-STICC_IMTA_MOM_PIM, Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Laboratoire des signaux et systèmes (L2S), Université Paris-Sud - Paris 11 (UP11)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), SpatialModulation Project under the French Research Agency [ANR-15-CE25-0016], ANR-15-CE25-0016,SpatialModulation,modulation spatiale et antenne reconfigurable pour connecter en haut débit des capteurs mobiles et autonomes en énergie(2015), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), IMT Atlantique (IMT Atlantique), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut d'Electronique et de Télécommunications de Rennes (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Institut Langevin - Ondes et Images, Université Paris Diderot - Paris 7 (UPD7)-ESPCI ParisTech-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec-Université Paris-Sud - Paris 11 (UP11), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL), Département Micro-Ondes (IMT Atlantique - MO), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), and Centre National de la Recherche Scientifique (CNRS)

Subjects
Beamforming, Signal Processing (eess.SP), General Computer Science, Computer science, 02 engineering and technology, Communications system, Signal, law.invention, beamforming, Base station, [SPI]Engineering Sciences [physics], 0203 mechanical engineering, law, multiple input multiple output (MIMO), 0202 electrical engineering, electronic engineering, information engineering, Electronic engineering, FOS: Electrical engineering, electronic engineering, information engineering, Waveform, compact antennas, General Materials Science, [INFO]Computer Science [cs], Electrical Engineering and Systems Science - Signal Processing, ComputingMilieux_MISCELLANEOUS, Computer Science::Information Theory, Reconfigurable antenna, Amplifier, General Engineering, 020206 networking & telecommunications, 020302 automobile design & engineering, receive antenna shift keying (RASK), Spatial modulation, [SPI.TRON]Engineering Sciences [physics]/Electronics, Spatial modulation (SM), Modulation, [INFO.INFO-IT]Computer Science [cs]/Information Theory [cs.IT], reconfigurable antennas, Cellular network, lcsh:Electrical engineering. Electronics. Nuclear engineering, Antenna (radio), lcsh:TK1-9971, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing
Abstract

In this paper, for the first time, we propose two new solutions to boost the data rate between small connected objects such as glasses and cams and the 5th generation (5G) mobile network, based on spatial modulation, single carrier waveform, compact reconfigurable antennas at the object side and massive multiple input multiple output (M-MIMO) at the network side. In the first new wireless communication system, a "transmitting object" uses transmit spatial modulation with a compact reconfigurable antenna and a constant envelop amplifier to transmit in high data rate with a low complexity and low power consumption. The space-time digital processing capability of the M-MIMO 5G base station is used to detect such signal. In the second new wireless communication system, a "receiving object" uses receive spatial modulation, a compact multiport antenna and a low complexity detection algorithm to receive in high data rate with a low complexity signal processing. The space-time beamforming capability of the M-MIMO 5G base stations is exploited to deliver a signal that is pre-equalized enough to be detected by the object. For the first time, we present experiments showing that M-MIMO allows for the re-introduction of single carrier modulation waveform. For the first time, we present performance results obtained with real existing compact antennas and compact reconfigurable antennas, showing that the two new communication systems outperform conventional modulation in terms of energy efficiency and complexity., Submitted for publication to IEEE journal

Published
2018
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32. Dual-tuned birdcage-like coil based on metasurfaces

Author

Abdelwaheb Ourir, A. Nikulin, Redha Abdeddaim, Frank Kober, Benoit Larrat, Julien de Rosny, Stanislav Glybovski, Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL), National Research University of Information Technologies, Mechanics and Optics [St. Petersburg] (ITMO), Unité d'imagerie par résonance magnétique à très haut champ et de spectroscopie (UNIRS), Service NEUROSPIN (NEUROSPIN), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre de résonance magnétique biologique et médicale (CRMBM), Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Centre National de la Recherche Scientifique (CNRS), CLARTE (CLARTE), Institut FRESNEL (FRESNEL), Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM)-Centre National de la Recherche Scientifique (CNRS), European Project: 736937,H2020,H2020-FETOPEN-1-2016-2017,M-CUBE(2017), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-École Centrale de Marseille (ECM)-Aix Marseille Université (AMU), and ESPCI ParisTech

Subjects
Materials science, business.industry, [SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging, Metal strips, 02 engineering and technology, 021001 nanoscience & nanotechnology, Rod, 030218 nuclear medicine & medical imaging, law.invention, 03 medical and health sciences, Capacitor, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, 0302 clinical medicine, Optics, Electromagnetic coil, law, Scattering parameters, Radio frequency, 0210 nano-technology, business, ComputingMilieux_MISCELLANEOUS
Abstract

International audience; We propose the dual-tuned volume coil for magnetic resonance imaging at two nuclei. This coil is based on the combination of two independent metasurfaces that can be used simultaneously for fluorine and hydrogen 19 F / 1 H imaging at 7 Tesla for small animals. Each metasurface is made of non-magnetic metallic rods and structural capacities of etched metal strips. The geometry is chosen so that two modes supported by the two metasurfaces resonate at the required frequencies 282.6/300.1 MHz. The two metasurfaces can be tuned independently by mechanically adjusting the length of the two sets of wires. We have numerically studied the concept of the proposed dual-tuned coil.

Published
2018
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34. Effective birefringence to analyze sound transmission through a layer with subwavelength slits

Author

Abdelwaheb Ourir, Jean-François Mercier, Agnès Maurel, Simon Félix, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire d'Acoustique de l'Université du Mans (LAUM), Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), Propagation des Ondes : Étude Mathématique et Simulation (POEMS), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Unité de Mathématiques Appliquées (UMA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Acoustic array, Sound transmission class, Strategy and Management, Physics::Optics, Near and far field, Réseau acoustique, Homogenization (chemistry), Metamaterial, Spoof plasmon, Métamatériau, Optics, Dispersion relation, Media Technology, General Materials Science, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Plasmon, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Marketing, Physics, Homogenization, Birefringence, business.industry, Wavelength, Homogénéisation, business
Abstract

International audience; We analyze the transmission of sound through a sound hard film or layer with periodic subwavelength slits. For wavelength comparable to or larger than the slit spacing, the transmission spectra are revisited in terms of the transmission through an equivalent birefringent layer. It is shown that the Fano-type resonances can be understood by means of the dispersion relations of guided waves within the birefringent layer in the homogenized problem, equivalent to spoof plasmons for gratings. This is done by extending the homogenization to the evanescent waves being excited in the near field of the actual perforated layer.; Nous analysons les spectres de transmission par une lame rigide perforée périodiquement de trous sub-longueur d'onde. Pour des longueurs d'onde comparables ou plus grandes que l'espacement des perforations, les spectres de transmission sont revisités en termes de transmission par une lame équivalente biréfringente. Nous montrons que les résonances de Fano se comprennent au vu des relations de dispersion d'ondes guidées par la couche biréfringente, similaires aux spoof plasmons dans les réseaux en réflexion. Ces relations de dispersion sont obtenues en étendant l'homogénéisation aux ondes évanescentes excitées en champ proche dans le problème réel.

Published
2015
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35. Homogenization of Thin and Thick Metamaterials and Applications

Author

Yao Gao, Jean-Jacques Marigo, Agnès Maurel, Abdelwaheb Ourir, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire de mécanique des solides (LMS), École polytechnique (X)-MINES ParisTech - École nationale supérieure des mines de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), and Alejandro Lucas Borja

Subjects
multiplexing, Materials science, Demultiplexer, guided waves, subwavelength devices, Mathematical analysis, homogenization, Metamaterial, metamaterial, surface waves, 01 natural sciences, Homogenization (chemistry), Multiplexing, spoof plasmons, [PHYS.MECA.ACOU]Physics [physics]/Mechanics [physics]/Acoustics [physics.class-ph], Magnetic field, 010309 optics, Complex geometry, Homogeneous, Surface wave, [PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph], 0103 physical sciences, 010306 general physics
Abstract

International audience; The wave propagation in structures involving metamaterials can be described owing to homogenization approaches which allow to replace the material structured at the subwavelength scale by an equivalent and simpler, effective medium. In its simplest form, homogenization predicts that the equivalent medium is homogeneous and aniso-tropic and it is associated to the usual relations of continuity for the electric and magnetic fields at the boundaries of the metamaterial structure. However, such prediction has a range of validity which remains limited to relatively thick devices and it is not adapted to more involved geometries (notably three-dimensional). The following two aspects are considered: (i) we study how the homogenization at the leading order can be improved when the thickness of the device becomes small and (ii) we propose a heuris-tic extension of the solution given by the leading order homogenization in order to deal with a complex geometry; in the latter case, an application to a demultiplexer device is proposed.

Published
2017
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36. Compact reconfigurable antenna with radiation pattern diversity for spatial modulation

Author

Kammel Rachedi, Dinh-Thuy Phan-Huy, J. de Rosny, Abdelwaheb Ourir, and Christian Leray

Subjects
Patch antenna, Engineering, Reconfigurable antenna, business.industry, 020208 electrical & electronic engineering, Antenna measurement, 020206 networking & telecommunications, 02 engineering and technology, Antenna efficiency, law.invention, Radiation pattern, Optics, law, 0202 electrical engineering, electronic engineering, information engineering, Dipole antenna, Antenna (radio), business, Monopole antenna
Abstract

We design a compact reconfigurable antenna suitable for integrable communication systems based on spatial modulation. This recent technique is a simple implementation of multiple-input multiple-output communication scheme. The reconfigurable antenna is based on a meander line radiating element surrounded by two L-shaped wire resonators connected to a metallic ground plane with two PIN diodes. By switching these lasts, this subwavelength (λ/5) printed antenna can generate four different radiation patterns. The cross-correlations between the different patterns range between 11% to 95% that match the requirements of spatial modulation. To increase the number of patterns, two other geometries are proposed.

Published
2017
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37. Reconfigurable Compact Antenna for Spatial Modulation MIMO Communications

Author

Kammel Rachedi, Julien de Rosny, Abdelwaheb Ourir, Dinh-Thuy Phan-Huy, Laboratoire Ondes et Acoustique (UMR 7587) (LOA), Université Paris Diderot - Paris 7 (UPD7)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Computer Networks and Communications, Computer science, MIMO, Impedance matching, Data_CODINGANDINFORMATIONTHEORY, 7. Clean energy, law.invention, Non-line-of-sight propagation, Hardware_GENERAL, law, Media Technology, Electronic engineering, Wireless, Electrical and Electronic Engineering, ComputingMilieux_MISCELLANEOUS, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Computer Science::Information Theory, Reconfigurable antenna, business.industry, ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKS, Antenna diversity, Hardware and Architecture, Signal Processing, Bit error rate, Antenna (radio), business
Abstract

Recently, a new wireless communication scheme called Spatial Modulation MIMO (SM-MIMO) has been introduced for Green wireless communications. Here, an application of a compact reconfigurable antenna working at 2.45 GHz to SM-MIMO is presented. The designed antenna can generate up to eight different radiation patterns. It is composed of two meanderlines radiating elements surrounded by parasitic electronically switchable resonators. The impedance matching has been optimized for six states of the reconfigurable antenna. The spatial diversity, which is a key parameter for SM-MIMO is estimated from the analysis of the complex inter-correlation matrix of the radiation patterns at the operating frequency. Finally, the performance of the designed reconfigurable antenna is assessed by computing the bit error rate (BER) in a Non-Line-of-Sight (NLOS) configuration. The proposed reconfigurable antennas are particularly suitable for indoor SM-MIMO applications that require low power and compact devices.

Published
2019
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38. Manipulating light at subwavelength scale by exploiting defect-guided spoof plasmon modes

Author

Jean-François Mercier, Abdelwaheb Ourir, Agnès Maurel, Mathias Fink, Simon Félix, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire d'Acoustique de l'Université du Mans (LAUM), Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), Propagation des Ondes : Étude Mathématique et Simulation (POEMS), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Unité de Mathématiques Appliquées (UMA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS), ANR-10-IDEX-0001,PSL,Paris Sciences et Lettres(2010), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], business.industry, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Wavelength demultiplexer, Rod, Optics, Photonic crystal waveguides, Surface wave, Dispersion relation, 0103 physical sciences, Optoelectronics, 010306 general physics, 0210 nano-technology, business, Microwave, Plasmon, Leakage (electronics)
Abstract

International audience; We study the defect-guided modes supported by a set of metallic rods structured at the subwavelength scale. Following the idea of photonic crystal waveguide, we show that spoof plasmon surface waves can be manipulated at subwavelength scale. We demonstrate that these waves can propagate without leakage along a row of rods having a different length than the surrounding medium and we provide the corresponding dispersion relation. The principle of this subwavelength colored guide is validated experimentally. This allows us to propose the design of a wavelength demultiplexer whose efficiency is illustrated in the microwave regime.

Published
2017
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39. Light scattering by periodic rough surfaces: equivalent jump conditions

Author

Abdelwaheb Ourir, Bruno Gallas, Jean-Jacques Marigo, Agnès Maurel, Croissance et propriétés de systèmes hybrides en couches minces (INSP-E8), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de mécanique des solides (LMS), École polytechnique (X)-Mines Paris - PSL (École nationale supérieure des mines de Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), and École polytechnique (X)-MINES ParisTech - École nationale supérieure des mines de Paris

Subjects
Brewster's angle, Materials science, Scattering, business.industry, Surface finish, Dielectric, 01 natural sciences, Homogenization (chemistry), Atomic and Molecular Physics, and Optics, Light scattering, Electronic, Optical and Magnetic Materials, 010309 optics, symbols.namesake, Optics, 0103 physical sciences, [PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph], symbols, Jump, Computer Vision and Pattern Recognition, Reflection coefficient, 010306 general physics, business
Abstract

International audience; We present an interface model based on two-scale homogenization to predict the coherent scattering of light by a periodic rough interface between air and a dielectric. Contrary to previous approaches where the roughnesses are replaced by a layer filled with an equivalent medium, our modeling yields effective jump conditions applying across the region containing the roughnesses. The validity of the model is inspected by comparison with direct numerics and with experimental measurements on a air/silicium rough interface near the Brewster angle. It is shown that the interface model reproduces accurately the shift in the Brewster phenomenon without any ajustable parameter, which is of practical importance in retrieval methods to get thickness or filling fraction with reliable physical values.

Published
2017
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40. SURFACE WAVES RADIATION BY FINITE ARRAYS OF MAGNETOELECTRIC RESONATORS

Author

Julien de Rosny, Abdelwaheb Ourir, and Camille Jouvaud

Subjects
Coupling, Physics, Radiation, business.industry, Condensed Matter Physics, Computational physics, Resonator, Wavelength, Dipole, Optics, Surface wave, Q factor, Wavenumber, Electrical and Electronic Engineering, business, Magnetic dipole
Abstract

We study the propagation of waves on inflnite and flnite size arrays made of subwavelength magnetoelectric resonators. We propose an analytical study where each magnetoelectric resonator is modelled simultaneously by an electric and a magnetic dipole. We show how near fleld coupling and wavenumber quantiflcation due to the flnite size of the structure induce a frequency splitting of the resonator fundamental mode. We theoretically demonstrate that despite a spatial period of the waves smaller than half wavelength (in vacuum), the structure can e-ciently emits radiations. An analytic expression of the Q factor associated to the radiation losses is proposed. To correctly estimate this factor, we show that not only near but also far fleld interaction terms between the dipoles must to be considered.

Published
2012
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41. TUNABLE TRAPPED MODE IN SYMMETRIC RESONATOR DESIGNED FOR METAMATERIALS

Author

Julien de Rosny, Redha Abdeddaim, and Abdelwaheb Ourir

Subjects
Physics, Radiation, Dielectric resonator antenna, business.industry, Antisymmetric relation, Metamaterial, Condensed Matter Physics, Symmetry (physics), Resonator, Optics, Mode coupling, Optoelectronics, Electrical and Electronic Engineering, business, Excitation, Helical resonator
Abstract

The excitation of an antisymmetric trapped mode on a symmetric metamaterial resonator is experimentally demonstrated. We use an active electronic device to break the electrical symmetry and therefore to generate this trapped mode on a symmetric spilt ring resonator. Even more, with such a tunable mode coupling resonator, we can precisely tune the resonant mode frequency. In this way, a shift of up to 15 percent is observed.

Published
2010
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42. Achieving Antenna Isolation within Subwavelength Directive Cavity

Author

Abdelwaheb Ourir, Redha Abdeddaim, and J. de Rosny

Subjects
Patch antenna, Materials science, Coaxial antenna, business.industry, Antenna measurement, General Physics and Astronomy, Electronic, Optical and Magnetic Materials, law.invention, Radiation pattern, Antenna array, Microstrip antenna, Optics, law, Optoelectronics, Dipole antenna, Electrical and Electronic Engineering, business, Monopole antenna
Abstract

Antenna arrays embedded within a compact Fabry-Perot cavity have to be optimized to limit interactions between elementary antennas. In this article, we propose to use a superstrate metamaterial to design a highly isolated antenna array. This superstrate is based on the microstrip technology. It is made of an inductive and a capacitive grid respectively etched on the top and the bottom of epoxy plate. Metallic vias are then inserted through the superstrate to connect the two etched grids. This superstrate combined with a metallic ground plane leads to the design of a subwavelength cavity. The proposed cavity allows a significant antenna profile reduction and performance enhancement. More importantly, this structure provides a high isolation for an antenna array.

Published
2010
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43. Metamaterial-based phased array for directional beam steering

Author

Abdelwaheb Ourir and A. de Lustrac

Subjects
Engineering, Phased-array optics, business.industry, Phased array, Beam steering, Directive antennas, Metamaterial, Radiation, Condensed Matter Physics, Directivity, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Optics, Optoelectronics, Electrical and Electronic Engineering, business, Microwave
Abstract

Ultracompact metamaterial-based cavity (thickness λ/15) is proposed to realize a low secondary lobes level and highly directive phased array antenna. The cavity is fed by an array of four patch antennas designed to operate at around 9.5 GHz. The radiation patterns of the phased arrays are compared with those of their respective metamaterial-based cavity antennas. The latter structures have lower secondary lobes and provide higher gain and directivity. Moreover, the cavities enhance the beam steering of the phased arrays. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 2653–2656, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24709

Published
2009
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44. Directive metamaterial-based subwavelength resonant cavity antennas – Applications for beam steering

Author

Shah Nawaz Burokur, Abdelwaheb Ourir, André de Lustrac, Riad Yahiaoui, Institut d'électronique fondamentale (IEF), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Directional antenna, business.industry, Beam steering, General Engineering, Phase (waves), Physics::Optics, Energy Engineering and Power Technology, Metamaterial, 020206 networking & telecommunications, 02 engineering and technology, 021001 nanoscience & nanotechnology, Ray, Microstrip, [SPI]Engineering Sciences [physics], Optics, visual_art, Electronic component, 0202 electrical engineering, electronic engineering, information engineering, visual_art.visual_art_medium, Optoelectronics, 0210 nano-technology, business, Metamaterial antenna
Abstract

International audience; This article presents the use of composite resonant metamaterials for the design of highly directive subwavelength cavity antennas. These metamaterials, composed of planar metallic patterns periodically organized on dielectric substrates, exhibit frequency dispersive phase characteristics. Different models of metamaterial-based surfaces (metasurfaces), introducing a zero degree reflection phase shift to incident waves, are firstly studied where the bandwidth and operation frequency are predicted. These surfaces are then applied in a resonant Fabry-Perot type cavity and a ray optics analysis is used to design different models of ultra-compact high-gain microstrip printed antennas. Another surface presenting a variable reflection phase by the use of a non-periodic metamaterial-based metallic strips array is designed for a passive low-profile steering beam antenna application. Finally, the incorporation of active electronic components on the metasurfaces, allowing an electronic control of the phase responses, is applied to an operation frequency reconfigurable cavity and a beam steering cavity. All these cavity antennas operate on subwavelength modes, the smallest cavity thickness being of the order of lambda/60. To cite this article: A. Outir et al., C R. Physique 10 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Published
2009
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45. Highly directive ISM band cavity antenna using a bi-layered metasurface reflector

Author

Philippe Ratajczak, Jean-Pierre Daniel, Shah Nawaz Burokur, Abdelwaheb Ourir, André de Lustrac, Laboratoire Energétique Mécanique Electromagnétisme (LEME), Université Paris Nanterre (UPN), Institut Langevin - Ondes et Images (UMR7587) (IL), Sorbonne Université (SU)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Paris (UP)-Centre National de la Recherche Scientifique (CNRS), Ecole Nationale de l'Aviation Civile (ENAC), Gvh et Gvl : Physiopathologie Chez l'Homme et Chez l'Animal, Incidence et Role Therapeutique, Université Paris Diderot - Paris 7 (UPD7)-Institut National de la Santé et de la Recherche Médicale (INSERM), IEF, Université Paris-Sud - Paris 11 (UP11), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Patch antenna, Engineering, Coaxial antenna, business.industry, Antenna measurement, 020206 networking & telecommunications, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, Radiation pattern, law.invention, [SPI]Engineering Sciences [physics], Microstrip antenna, Optics, law, 0202 electrical engineering, electronic engineering, information engineering, Dipole antenna, Electrical and Electronic Engineering, 0210 nano-technology, business, Monopole antenna, ComputingMilieux_MISCELLANEOUS, Metamaterial antenna
Abstract

The design of a highly directive metamaterial-based cav- ity antenna for a 2.46 GHz application is reported. The proposed struc- ture is evolved from a Fabry-Perot (FP) cavity with a patch antenna acting as the feed and four metallic walls on the lateral sides. One of the two reflectors is the antenna's ground plane and the other is made from a bilayered metamaterial-based partially reflecting surface (PRS) constituted by a capacitive and an inductive grid. Calculations together with experimental results obtained from the fabricated prototype are presented. The results show a high directivity and low levels for the sec- ondary lobes compared to a 2 2 patch antenna array. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1393-1396, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24391

Published
2009
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46. Optimization of metamaterial based subwavelength cavities for ultracompact directive antennas

Author

Abdelwaheb Ourir, A. de Lustrac, and Jean-Michel Lourtioz

Subjects
Engineering, Frequency band, business.industry, Metamaterial, Condensed Matter Physics, Directivity, Atomic and Molecular Physics, and Optics, Microstrip, Electronic, Optical and Magnetic Materials, Microstrip antenna, Optics, Electronic engineering, Electrical and Electronic Engineering, business, Electrical impedance, Microwave, Metamaterial antenna
Abstract

Artificial magnetic conductors (AMC) are proposed for the fabrication of subwavelength cavities in the microstrip technology. These metamaterials can simultaneously present a low phase value at reflection and a high impedance for normal incident waves over a wide frequency band. Planar cavities using AMC-based reflectors are applicable to the design of ultracompact directive antennas. An optimized cavity structure is presently shown to provide a significant enhancement of the gain and directivity of a microstrip antenna near 10 GHz. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 2573–2577, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21996

Published
2006
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47. Classical homogenization to analyse the dispersion relations of spoof plasmons with geometrical and compositional effects

Author

Abdelwaheb Ourir, Simon Félix, Agnès Maurel, Jean-François Mercier, María Luisa Cordero, Propagation des Ondes : Étude Mathématique et Simulation (POEMS), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Unité de Mathématiques Appliquées (UMA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS), Departamento de Fisica [UC Santiago], Pontificia Universidad Católica de Chile (UC), Laboratoire d'Acoustique de l'Université du Mans (LAUM), Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS), Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)

Subjects
Materials science, dispersion relation, General Mathematics, homogenization, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, 01 natural sciences, Homogenization (chemistry), compositionaleffects, Optics, Effective mass (solid-state physics), Electromagnetism, Dispersion relation, 0103 physical sciences, geometrical effects, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, 010306 general physics, Plasmon, [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Bulk modulus, business.industry, General Engineering, 021001 nanoscience & nanotechnology, effective medium, Classical mechanics, Slab, 0210 nano-technology, business, Material properties, spoofplasmons
Abstract

International audience; We show that the classical homogenization is able to describe the dispersion relation of spoof plasmons in structured thick interfaces with periodic unit cell being at the subwavelength scale. This is because the interface in the real problem is replaced by a slab of an homogeneous birefringent medium, with an effective mass density tensor and an effective bulk modulus. Thus, explicit dispersion relation can be derived, corresponding to guided waves in the homogenized problem. Contrary to previous effective medium theories or retrieval methods, the homogenization gives effective parameters depending only on the properties of the material and on the geometry of the microstructure. Although resonances in the unit cell cannot be accounted for within this low-frequency homogenization, it is able to account for resonances occurring because of the thickness of the interface and thus, to capture the behaviour of the spoof plasmons. Beyond the case of simple grooves in a hard material, we inspect the influence of tilting the grooves and the influence of the material properties.

Published
2015
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48. Subwavelength far-field imaging at visible and ultraviolet wavelengths using broadband surface plasmon waves

Author

Mathias Fink and Abdelwaheb Ourir

Subjects
Physics, 3D optical data storage, business.industry, Surface plasmon, Physics::Optics, Near and far field, Condensed Matter Physics, Surface plasmon polariton, Electronic, Optical and Magnetic Materials, Wavelength, Resonator, Optics, Slab, Optoelectronics, business, Localized surface plasmon
Abstract

The optical diffraction limit has stood for a long time in the way of achieving higher optical resolution in far-field imaging, photolithography, and optical data storage. We present here a simple and original concept for broadband far-field imaging in the visible and ultraviolet range that beats this limit. A finite-sized ultrathin metallic slab is used to encode subwavelength details of the broadband field radiated by an object. This field excites a set of surface plasmon modes on the finite-sized slab that radiates in the far field. A numerical time reversal imaging process is applied to reconstruct the image of the object with a resolution smaller than \ensuremath{\lambda}/6 for a gold slab and \ensuremath{\lambda}/8 for a silver slab. With these structures, the highest spatial frequencies are no longer limited by the pitch of the array of the subwavelength resonators as in classical metalenses. We show that the resolution depends mainly on the intrinsic properties of the metal but can be slightly controlled by the geometry design of the slab. Thanks to advances in the control of light in space and time, this concept would provide a promising alternative for high-resolution imaging techniques in the visible and ultraviolet range.

Published
2014
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49. Wood's anomalies for arrays of dielectric scatterers

Author

Agnès Maurel, Jean-François Mercier, Abdelwaheb Ourir, Simon Félix, Zine Eddine Djeffal, Institut Langevin - Ondes et Images (UMR7587) (IL), Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Laboratoire d'Acoustique de l'Université du Mans (LAUM), Centre National de la Recherche Scientifique (CNRS)-Le Mans Université (UM), Propagation des Ondes : Étude Mathématique et Simulation (POEMS), Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Unité de Mathématiques Appliquées (UMA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), and Le Mans Université (UM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], Physics, Field (physics), business.industry, Physics::Optics, Dielectric, Grating, 01 natural sciences, Electromagnetic radiation, Atomic and Molecular Physics, and Optics, Admittance parameters, 010309 optics, symbols.namesake, Optics, 0103 physical sciences, Reflection (physics), symbols, Wave impedance, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Rayleigh scattering, 010306 general physics, business, ComputingMilieux_MISCELLANEOUS
Abstract

The Rayleigh Wood anomalies refer to an unexpected repartition of the electromagnetic energy between the several interference orders of the light emerging from a grating. Since Hessel and Oliner (Appl. Opt. 4, 1275-1297 (1965)), several studies have been dedicated to this problem, focusing mainly on the case of metallic gratings. In this paper, we derive explicit expressions of the reflection coefficients in the case of dielectric gratings using a perturbative approach. This is done in a multimodal description of the field combined with the use of the admittance matrix, analog to the so-called electromagnetic impedance. Comparisons with direct numerical calculations show a good agreement with our analytical prediction.

Published
2014
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