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Cross-Layer Energy Analysis and Proposal of a MAC Protocol for Wireless Sensor Networks Dedicated to Building Monitoring Systems

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Wireless Sensor Network 2013年第5期5卷 91-104页

作者： Denis Dessales Noel Richard Anne-Marie Poussard Rodolphe Vauzelle Christophe Martinsons xlim Laboratory SIC departmentUniversity of PoitiersPoitiersFrance Department of Health and Comfort Centre Scientifique et Technique du BatimentSt Martin d’HèresFrance

In a sustainable development context, the monitoring systems are essential to study the building energy performances. With the recent technology advances, these systems can be based on wireless sensor networks, where the energy efficiency is the main design challenge. To this end, most of the studies focus on low power Medium Access Control (MAC) protocols to reduce the overall energy consumption of a network. Nevertheless, the performances assessment of these protocols is generally not performed in a realistic way, and does not take into account the performances of the other layers of the OSI model. In this paper, we propose a cross-layer methodology to assess the real performances of a MAC protocol by taking into account the traffic volume, the synchronization losses and more particularly the physical layer performances through a Bit Error Rate (BER) criterion. The simulation results demonstrate clearly the physical layer impact on a sensor lifetime. Finally, the proposal of an energy efficient MAC protocol for a wireless sensor network dedicated to an application of building monitoring is proposed.

关键词： WSN Physical Layer MAC Layer Energy Consumption Cross-Layer Analysis

Shaping the light amplified in a multimode fiber

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Light(Science & Applications) 2016年第1期5卷 250-258页

作者： Raphael Florentin Vincent Kermene Joel Benoist Agnès Desfarges-Berthelemot Dominique Pagnoux Alain Barthélémy Jean-Pierre Huignard xlim Research Institute Universitéde Limoges-Centre National de la Recherche ScientifiqueUMR 625287060 LimogesFrance Institut Langevin ESPCI-ParisTech75238 ParisFrance

Propagation of light in multimode optical fibers usually gives a spatial and temporal randomization of the transmitted field similar to the propagation through scattering *** still applies when scattering or multimode propagation occurs in gain *** demonstrate that appropriate structuration of the input beam wavefront can shape the light amplified by a rareearth-doped multimode *** of the wavefront was achieved by a deformable mirror in combination with an iterative optimization *** present experimental results and simulations showing the shaping of a single sharp spot at different places in the output cross-section of an ytterbium-doped fiber *** and narrowing of the amplifier far-field pattern was realized as *** the wavefront to shape the amplified light can also serve to improve the effective *** shaping approach still works under gain saturation,showing the robustness of the *** and experiments attest that the shaping is effective even with a highly multimode fiber amplifier carrying up to 127 modes.

关键词： adaptive optics amplification beam shaping complex media multimode optical fiber

Spatiotemporal mode decomposition of ultrashort pulses in linear and nonlinear graded-index multimode fibers

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Photonics Research 2023年第5期11卷 750-756页

作者： MARIO ZITELLI VINCENT COUDERC MARIO FERRARO FABIO MANGINI PEDRO PARRA-RIVAS YIFAN SUN STEFAN WABNITZ Department of Information Engineering Electronics and TelecommunicationsUniversitàdegli Studi di Roma Sapienza00184 RomeItaly Universitéde Limoges XLIMUMR CNRS 725287060 LimogesFrance CNR-INO Istituto Nazionale di Ottica80078 PozzuoliItaly

We develop a spatiotemporal mode decomposition technique to study the spatial and temporal mode power distribution of ultrashort pulses in long spans of graded-index multimode fiber,for different input laser *** find that the beam mode power content in the dispersive pulse propagation regime can be described by the Bose-Einstein law,as a result of the process of power diffusion from linear and nonlinear mode coupling among nondegenerate mode *** the soliton regime,the output mode power distribution approaches the Rayleigh-Jeans law.

关键词： ultrashort multimode mode

Rotorcraft with a 3DOF Rigid Manipulator:Quaternion-based Modeling and Real-time Control Tolerant to Multi-body Couplings

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International Journal of Automation and computing 2018年第5期15卷 547-558页

作者： J.Alvarez-Munoz N.Marchand J.F.Guerrero-Castellanos J.J.Tellez-Guzman J.Escareno M.Rakotondrabe Polytechnic Institute of Advanced Sciences FR 94200 ParisFrance Univ.Grenoble Alpes GIPSA-LabFR-38000 GrenobleFrance Autonomous University of Puebla(BUAP) Faculty of ElectronicsMX 72570 PueblaMexico University of Limoges ENSIL-ENSCI XLIM Laboratory UMR CNRS 7252Parc Ester Technopole16 rue AtlantisLimoges 87068France FEMTO-ST Institute UMR CNRS-UFC/ENSMM/UTBMAutomatic Control and Micro-Mechatronic DepartmentFR BesanconFrance

This paper proposes a simple solution for the stabilization of a mini-quadcopter carrying a 3DoF（degrees of freedom） manipulator robot in order to enhance its achievable workspace and application profile. Since the motion of the arm induces torques which degrade the stability of the system, in the present work, we consider the stabilization of both subsystems： the quadcopter and the robotic arm. The mathematical model of the system is based on quaternions. Likewise, an attitude control law consisting of a bounded quaternion-based feedback stabilizes the quadcopter to a desired attitude while the arm is evolving. The next stage is the translational dynamics which is simplified for control（nonlinear） design purposes. The aforementioned controllers are based on saturation functions whose stability is explicitly proved in the Lyapunov sense. Finally, experimental results and a statistical study validate the proposed control strategy.

关键词： Observer-based control quaternion and Newton-Euler modeling bounded-input control aerial manipulator disturbancerejection.

Targeted Sub-Attomole Cancer Biomarker Detection Based on Phase Singularity 2D Nanomaterial-Enhanced Plasmonic Biosensor

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Nano-Micro Letters 2021年第6期13卷 284-294页

作者： Yuye Wang Shuwen Zeng Aurelian Crunteanu Zhenming Xie Georges Humbert Libo Ma Yuanyuan Wei Aude Brunel Barbara Bessette Jean-Christophe Orlianges Fabrice Lalloué Oliver GSchmidt Nanfang Yu Ho-Pui Ho Department of Biomedical Engineering The Chinese University of Hong KongShatinNew TerritoriesHong KongPeople’s Republic of China CNRS XLIM Research InstituteUMR 7252University of Limoges123Avenue Albert ThomasLimogesFrance Department of Applied Physics and Applied Mathematics Columbia UniversityNew York CityNYUSA Institute for Integrative Nanosciences IFW DresdenHelmholtzstr.20DresdenGermany Faculty of Medicine University of LimogesEA3842-CAPTuRGEIST2 rue du Dr MarclandLimogesFrance

Detection of small cancer biomarkers with low molecular weight and a low concentration range has always been challenging yet urgent in many clinical applications such as diagnosing early-stage cancer,monitoring treatment and detecting ***,a highly enhanced plasmonic biosensor that can overcome this challenge is developed using atomically thin two-dimensional phase change *** precisely engineering the configuration with atomically thin materials,the phase singularity has been successfully achieved with a significantly enhanced lateral position shift *** on our knowledge,it is the first experimental demonstration of a lateral position signal change>340μm at a sensing interface from all optical *** this enhanced plasmonic effect,the detection limit has been experimentally demonstrated to be 10^(-15) mol L^(−1) for TNF-α cancer marker,which has been found in various human diseases including inflammatory diseases and different kinds of *** as-reported novel integration of atomically thin Ge_(2)Sb_(2)Te_(5) with plasmonic substrate, which results in a phase singularity and thus a giant lateral position shift, enables the detection of cancer markers with low molecular weight at femtomolar level. These results will definitely hold promising potential in biomedical application and clinical diagnostics.

关键词： 2D nanomaterials Cancer marker detection Phase singularity Surface plasmon

Emulation of Realistic Multi-Path Propagation Channels inside an Anechoic Chamber for Antenna Diversity Measurements

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Wireless Engineering and Technology 2020年第1期11卷 1-12页

作者： Alaa Choumane Ahmad El Sayed Ahmad Khaled Khoder xlim O.S.A. Department—UMR CNRS 6172 University of Limoges Limoges France Faculty of Public Health Lebanese University Zahle Lebanon Faculty of Sciences Lebanese University Tripoli Lebanon Azm Institute Department of Innovation and Technology Tripoli Lebanon

As antennas are inherently included recommended in Over-The-Air (OTA) testing, it is important to also consider realistic channel models for the multiple-input multiple-output (MIMO) device performance evaluation. This paper aims to emulate realistic multi-Path propagation channels in terms of angles of arrivals (AoA) and cross-polarization ratio (XPR) with Rayleigh fading, inside an anechoic chamber, for antenna diversity measurements. In this purpose, a practical multi-probe anechoic chamber measurement system (MPAC) with 24 probe antennas (SATIMO SG24) has been used. However, the actual configuration of this system is not able to reproduce realistic channels. Therefore, a new method based on the control of the SG24 probes has been developed. At first time, this method has been validated numerically through the comparison of simulated and analytical AoA probability density distributions. At the second time, the performance of an antenna diversity system inside the SG24 has been performed in terms of the correlation coefficient and diversity gain (DG) using an antenna reference system. Simulated and measurements results have shown a good agreement.

关键词： Channel Emulation Multi-Path OTA Measurements Antenna Diversity Measurements MIMO Correlation Coefficient Diversity Gain

Strong nonlinear optical effects in micro-confined atmospheric air

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Photonics Research 2019年第10期7卷 1134-1141页

作者： BENOIT DEBORD MARTIN MAUREL FREDERIC GEROME LUCA VINCETTI ANTON HUSAKOU FETAH BENABID GPPMM Group Xlim Research InstituteCNRS UMR 7252University of LimogesFrance GLOphotonics S.A.S 123 avenue Albert Thomas87060 LimogesFrance Department of Engineering“Enzo Ferrari” University of Modena and Reggio EmiliaI-41125 ModenaItaly Max Born Institute Max-Born-Str.2aD-12489 BerlinGermany

Historically, nonlinear optical phenomena such as spectral broadening by harmonic generation have been associated with crystals owing to their strong nonlinear refractive indices, which are in the range of 10-14cm^2∕*** association was also the result of the limited optical power available from early lasers and the limited interaction length that the laser–crystal interaction architecture could offer. Consequently, these limitations disqualified a large number of materials whose nonlinear coefficient is lower than n210-16cm^2∕W as suitable materials for nonlinear optics applications. For example, it is a common practice in most of optical laboratories to consider ambient or atmospheric air as a "nonlinear optically" inert medium due to its very low nonlinear coefficient(10.10^-19cm^2∕W) and low density. Today, the wide spread of high-power ultra-short pulse lasers on one hand, and low transmission loss and high-power handling of Kagome hollow-core photonic crystal fiber on the other hand, provide the necessary ingredients to excite strong nonlinear optical effects in practically any gas media, regardless of how low its optical nonlinear response is. By using a single table-top 1 m J ultra-short pulse laser and an air exposed inhibited-coupling guiding hollow-core photonic crystal fiber, we observed generation of supercontinuum and third harmonic generation when the laser pulse duration was set at 600 fs and Raman comb generation when the duration was 300 ps. The supercontinuum spectrum spans over 1000 THz and exhibits a typical spectral-density energy of 150 n J/nm. The dispersion profile of inhibited-coupling hollow-core fiber imprints a distinctive sequence in the supercontinuum generation, which is triggered by the generation of a cascade of four-wave mixing lines and concluded by solitonic dynamics. The Raman comb spans over 300 THz and exhibits multiple sidebands originating from N2 vibrational and ro-vibrational Raman transitions. With the growing use of ho

关键词： optical nonlinear ambient

Thermoelectric Properties of ZnO-P₂O₅/(Ni) Composites

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New Journal of Glass and Ceramics 2016年第3期6卷 19-27页

作者： Omar Oabi Abdelkarim Maaroufi Bruno Lucas Aumeur El Amrani Laboratory of Composite Materials Polymers and Environment Department of Chemistry Faculty of Sciences University Mohammed V Rabat-Agdal Morocco xlim UMR 6172-Université de Limoges/CNRS Limoges Cedex France LPSMS FST Errachidia University Moulay Ismail Meknès Errachidia Morocco

The overall purpose of the present study is basically to understand the manifestation of the thermo-electrical properties of the matrix ZnO-P2O5 first, and of the ZnO-P2O5 composites loaded with different volume fractions of nickel (Ni) as conductive fillers. In the matrix ZnO-P2O5, the values of electrical conductivity varied between 1.14 × 10-8 and 7.8 × 10-7 (S/cm), and the Seebeck coefficient value varied between minimal value 265 and maximal value 670 (μV/K) in the studied temperature. In composite ZnO-P2O5/Ni, it was shown that the Seebeck coefficient changed from high positive to negative values when the filler amount was increased, indicating a non-conducting to conducting phase transition. Such behavior exhibits that this transition is accompanied by the passing of carrier charge from p to n type. The study of thermoelectrically transport for high volume fraction of filler enabled the achievement, for the first time on this kind of composites, of an original transition called PTC transition. Thus, highest values of power factor (PF = S2 ≈ 2 × 10-3 W·m-1·K-2 at 407 K) were obtained, giving a possibility of industrial applications.

关键词： Zinc Phosphate Glasses Composites Seebeck Coefficient Power Factor

Evolution to 200G Passive Optical Network

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Computer Technology and Application 2012年第11期3卷 723-728页

作者： Mamadou Diallo Diouf Ahmed D. Kora Octave Ringar C. Aupetit-Berthelemot Ecole Superieure Multinationale des Telecommunications (ESMT) BP 10000 Dakar Senegal xlim UMR 6172 Dpt. C2S2 University of Limoges/CNRS Parc Ester Technopole 16 Rue Atlantis BP 6804 F87068 Limoges France

New generation passive optical network aims at providing more than 100 Gb/s capacity. Thanks to recent progress enabling a variety of optical transceivers up to 40 Gb/s, many evolution possibilities to 200G PONs （passive optical network） could be investigated. This work proposes two directly deployable cases of evolution to 200G PON based on the combination of these improved optical transceivers and WDM （wavelength division multiplexing）. The physical layer of the optical network has been simulated with OptiSystem software to show the communication links performances behavior when considering key components parameters in order to achieve good network design for a given area. The complexity of the proposed architectures and financial cost comparisons are also discussed.

关键词： PON (passive optical network) 200G PON NG PON fiber wideband networks.