Publications

2017

• Robust Adaptive Detection of Buried Pipes using GPR
  
  • Hoarau Q
  • Ginolhac G
  • Atto A M
  • Nicolas Jean-Marie
  Signal Processing, Elsevier, 2017, 132, pp.293–305. Detection of buried objects such as pipes using a Ground Penetrating Radar (GPR) is intricate for three main reasons. First, noise is important in the resulting image because of the presence of several rocks and/or layers in the ground, highly influencing the Probability of False Alarm (PFA) level. Also, wave speed and object responses are unknown in the ground and depend on the relative permit-tivity, which is not directly measurable. Finally, the depth of the pipes leads to strong attenuation of the echoed signal, leading to poor SNR scenarios. In this paper, we propose a detection method: (1) enhancing the signal of interest while reducing the noise and layer contributions, and (2) giving a local estimate of the relative permittivity. We derive an adaptive detector where the signal of interest is parametrised by the wave speed in the ground. For this detector, noise is assumed to follow a Spherically Invariant Random Vector (SIRV) distribution in order to obtain a robust detection. We use robust maximum likelihood-type covariance matrix estimators called M-estimators. To handle the significant amount of data, we consider regularised versions of said estimators. Simulation will allow to estimate the relation PFA-Threshold. Comparison is performed with standard GPR processing methods, showing the aptitude of the method in detecting pipes having low response levels with a reasonable PFA. (10.1016/j.sigpro.2016.07.001)
  DOI : 10.1016/j.sigpro.2016.07.001
• AVC to HEVC transcoder based on quadtree limitation
  
  • Mora Elie Gabriel
  • Cagnazzo Marco
  • Dufaux Frederic
  Multimedia Tools and Applications, Springer Verlag, 2017, 76 (6), pp.8991-9015. Following the finalization of the state-of-the-art High Efficiency Video Coding (HEVC) standard in January 2013, several new services are being deployed in order to take advantage of the superior coding efficiency (estimated at 50 % less bitrate for the same visual quality) that this standard provides over its predecessor: H.264 / Advanced Video Coding (AVC). However, the switch from AVC to HEVC is not trivial as most video content is still encoded in AVC. Consequently, there is a growing need for fast AVC to HEVC transcoders in the market today. While a trivial transcoder can be made by simply cascading an AVC decoder and an HEVC encoder, fast transcoding cannot be achieved. In this paper, we present an AVC to HEVC transcoder where decoded AVC blocks are first fused according to their motion similarity. The resulting fusion map is then used to limit the quadtree of HEVC coded frames. AVC motion vectors are also used to determine a better starting point for integer motion estimation. Experimental results show that significant transcoder execution time savings of 63 % can be obtained with only a 1.4 % bitrate increase compared to the trivial transcoder.
• AVC to HEVC transcoder based on quadtree limitation
  
  • Mora Elie Gabriel
  • Cagnazzo Marco
  • Dufaux Frederic
  Multimedia Tools and Applications, Springer Verlag, 2017, 76 (6), pp.8991-9015. Following the finalization of the state-of-the-art High Efficiency Video Coding (HEVC) standard in January 2013, several new services are being deployed in order to take advantage of the superior coding efficiency (estimated at 50 % less bitrate for the same visual quality) that this standard provides over its predecessor: H.264 / Advanced Video Coding (AVC). However, the switch from AVC to HEVC is not trivial as most video content is still encoded in AVC. Consequently, there is a growing need for fast AVC to HEVC transcoders in the market today. While a trivial transcoder can be made by simply cascading an AVC decoder and an HEVC encoder, fast transcoding cannot be achieved. In this paper, we present an AVC to HEVC transcoder where decoded AVC blocks are first fused according to their motion similarity. The resulting fusion map is then used to limit the quadtree of HEVC coded frames. AVC motion vectors are also used to determine a better starting point for integer motion estimation. Experimental results show that significant transcoder execution time savings of 63 % can be obtained with only a 1.4 % bitrate increase compared to the trivial transcoder. (10.1007/s11042-016-3498-8)
  DOI : 10.1007/s11042-016-3498-8
• Cybersecurity and Privacy Solutions in Smart Cities
  
  • Khatoun Rida
  • Zeadally Sherali
  IEEE Communications Magazine, Institute of Electrical and Electronics Engineers, 2017, 55 (3), pp.51-59. (10.1109/MCOM.2017.1600297CM)
  DOI : 10.1109/MCOM.2017.1600297CM
• Learning Attribute Representations for Remote Sensing Ship Category Classification
  
  • Oliveau Quentin
  • Sahbi Hichem
  IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, IEEE, 2017, 10 (6), pp.2830-2840.
• Controllable Rare Events in an Optically-Injected Fabry-Perot Semiconductor Laser
  
  • Schires Kevin
  • Grillot Frédéric
  , 2017.
• Dichotomic Sphere Decoder
  
  • Khsiba Mohamed-Achraf
  • Rekaya-Ben Othman Ghaya
  , 2017.
• Low phase noise CO-MB-OFDM optical burst transmitter for time and spectral optical aggregation
  
  • Han Bing
  • Gavignet Paulette
  • Pincemin Erwan
  • Guillossou Thierry
  • Cresseaux Michel
  • Le Brouster Dominique
  • Haentjens Benoît
  • Jaouën Yves
  , 2017, pp.paper TU3F.6.
• Time Domain Complex Radar Cross Section of Human Body for Breath-Activity Monitoring
  
  • Vo Tien Tu
  • Ouvry Laurent
  • Sibille Alain
  , 2017. The knowledge of the complex Radar Cross Section (RCS) of the human body in ultra-wide band can fully describe the breathing activity. In this paper, we investigate the time domain RCS so as to analyze the backscattered signal from the human body, for further respiratory monitoring in any aspect angle. The time domain RCS measurements are first calibrated with the monostatic radar measurement of a metallic sphere. Subsequently, the RCS of a human body phantom is measured over the full 0-360o angle, azimuth range, allowing to put forward the creeping wave around the body. Finally, we measure the RCS of a human person and its temporal variation, also in various aspect angles. The results, which show a mixture between breathing and other body movements, are valuable inputs for respiratory monitoring in various body postures.
• Traffic Analysis with Off-the-Shelf Hardware: Challenges and Lessons Learned
  
  • Martino Trevisan
  • Finamore Alessandro
  • Mellia M.
  • Munafo M.
  • Rossi Dario
  IEEE Communications Magazine, Institute of Electrical and Electronics Engineers, 2017, 55 (3), pp.163 - 169. In recent years, the progress in both hardware and software allows user-space applications to capture packets at 10 Gb/s line rate or more, with cheap COTS hardware. However, processing packets at such rates with software is still far from being trivial. In the literature, this challenge has been extensively studied for network intrusion detection systems, where per-packet operations are easy to parallelize with support of hardware acceleration. Conversely, the scalability of statistical traffic analyzers (STAs) is intrinsically complicated by the need to track per-flow state to collect statistics. This challenge has received less attention so far, and it is the focus of this work. We present and discuss design choices to enable a STA to collects hundreds of per-flow metrics at a multi-10-Gb/s line rate. We leverage a handful of hardware advancements proposed over the last years (e.g., RSS queues, NUMA architecture), and we provide insights on the trade-offs they imply when combined with state-of-the-art packet capture libraries and the multi-process paradigm. We outline the principles to design an optimized STA, and we implement them to engineer DPDKStat, a solution combining the Intel DPDK framework with the traffic analyzer Tstat. Using traces collected from real networks, we demonstrate that DPDKStat achieves 40 Gb/s of aggregated rate with a single COTS PC
• A Model-Driven Engineering Methodology to Design Parallel and Distributed Embedded Systems
  
  • Enrici Andrea
  • Apvrille Ludovic
  • Pacalet Renaud
  ACM Transactions on Design Automation of Electronic Systems, Association for Computing Machinery, 2017, 22 (2), pp.34:1-34:25. In MDE system-level approaches, the design of communication protocols and patterns is subject to the design of processing operations (computations) and to their mapping onto execution resources. However, this strategy allows to capture simple communication schemes (e.g., processor-bus-memory) and prevents to evaluate the performance of both computations and communications (e.g., impact of application traffic patterns onto the communication interconnect) in a single step. To solve these issues we introduce a novel design approach - the Ψ-chart - where we design communication patterns and protocols independently of a system’s functionality and resources, via dedicated models. At the mapping step, both application and communication models are bound to the platform resources and transformed to explore design alternatives for both computations and communications. We present the Ψ-chart and its implementation (i.e., communication models and Design Space Exploration) in TTool/DIPLODOCUS, a UML/SysML framework for the modeling, simulation, formal verification and automatic code generation of data-flow embedded systems. The effectiveness of our solution in terms of better design quality (e.g., portability, time) is demonstrated with the design of the physical layer of a ZigBee (IEEE 802.15.4) transmitter onto a multi-processor architecture. (10.1145/2999537)
  DOI : 10.1145/2999537
• Upper and lower bounds for the q-entropy of network models with application to network model selection
  
  • Chehreghani Mostafa Haghir
  • Abdessalem Talel
  Information Processing Letters, 2017, 119, pp.1-8. Graphs are important tools for modeling data in different biological, social and technological domains. The measurement of their complexity has theoretical and practical applications in many areas such as pattern recognition, graph clustering, network inference and network analysis. A widely used measure is the q-entropy. While this measure has extensively been studied for Erdos–Renyi (ER) random graphs, only few results have been reported for real-world networks that are typically scale-free or small-world graphs. In this paper, we study the q-entropy of scale-free graphs (generated by the Barabasi–Albert model) and small-world graphs (generated by the Watts–Strogatz model). We derive upper and lower bounds for the q-entropy and confirm our analytical studies by numerical simulations. We study the effect of the network parameters on the q-entropy for both scale-free and small-world graphs which yields to reveal some novel and interesting insights. For example, we show that the q-entropy of a Barabasi–Albert graph is usually larger than the q-entropy of a small-world graph with the same size and density, independent of the randomness degree of the small-world graph. We use the derived bounds as characteristics of real-world networks as well as network models. Therefore, based on the derived bounds, we propose a network model selection algorithm, that given a real-world network and a set of models, determines which of the models most likely generates the real-world network.
• Tabu search heuristic for competitive base station location problem
  
  • Coupechoux Marceau
  • Davydov Ivan
  • Iellamo Stefano
  , 2017, pp.325-330. We consider the base stations location problem with sharing. New operator arrives the market and competes with an existing network of another operator. Latter one can share BS cites with new operator, receiving a rent payment from him. We propose new model of realistic clients behavior and formulate the problem as a nonlinear integer programming problem. We propose a fast tabu search heuristic for this problem and provide some computational results.
• Privacy Preserving Encrypted Phonetic Search of Speech Data
  
  • Glackin Cornelius
  • Chollet Gérard
  • Dugan Nazim
  • Cannings Nigel
  • Wall Julie
  • Tahir Shahzaib
  • Gosh Ray Indranil
  • Rajarajan Muttukhrishnan
  , 2017.
• Millimeter Wave Antennas for Backhaul Networks
  
  • Enriquez José
  • Begaud Xavier
  • Huyart Bernard
  • Le Quang Trung
  • Zimmermann Ralph
  • Magne François
  , 2017.
• Community Detection in Signed Networks Based on Extended Signed Modularity
  
  • Murata Tsuyoshi
  • Sugihara Takahiko
  • Abdessalem Talel
  , 2017. Community detection is important for analyzing and visualizing given networks. In real world, many complex systems can be modeled as signed networks composed of positive and negative edges. Although community detection in signed networks has been attempted by many researchers, studies for detecting detailed structures remain to be done. In this paper, we extend modularity for signed networks, and propose a method for optimizing our modularity, which is an efficient hierarchical agglomeration algorithm for detecting communities in signed networks. Based on the experiments with large-scale real world signed networks such as Wikipedia, Slashdot and Epinions, our method enables us to detect communities and inner factions inside the communities. (10.1007/978-3-319-54241-6_6)
  DOI : 10.1007/978-3-319-54241-6_6
• Light-field image and video compression for future immersive applications
  
  • Dricot Antoine
  , 2017. Evolutions in video technologies tend to offer increasingly immersive experiences. However, currently available 3D technologies are still very limited and only provide uncomfortable and unnatural viewing situations to the users. The next generation of immersive video technologies appears therefore as a major technical challenge, particularly with the promising light-field (LF) approach. The light-field represents all the light rays (i.e. in all directions) in a scene. New devices for sampling/capturing the light-field of a scene are emerging fast such as camera arrays or plenoptic cameras based on lenticular arrays. Several kinds of display systems target immersive applications like Head Mounted Display and projection-based light-field display systems, and promising target applications already exist. For several years now this light-field representation has been drawing a lot of interest from many companies and institutions, for example in MPEG and JPEG groups. Light-field contents have specific structures, and use a massive amount of data, that represent a challenge to set up future services. One of the main goals of this work is first to assess which technologies and formats are realistic or promising. The study is done through the scope of image/video compression, as compression efficiency is a key factor for enabling these services on the consumer markets. Secondly, improvements and new coding schemes are proposed to increase compression performance in order to enable efficient light-field content transmission on future networks. (10.70675/71bed830z0b60z4585z914bz01bb0f77d84a)
  DOI : 10.70675/71bed830z0b60z4585z914bz01bb0f77d84a
• Carrier Aggregation of Three OFDM Signals Using a Single Oscillator and I/Q Modulator
  
  • Abdi Abyaneh Mohammad
  • Huyart Bernard
  • Cousin Jean-Christophe
  IEEE Transactions on Microwave Theory and Techniques, Institute of Electrical and Electronics Engineers, 2017, PP (99), pp.1-9. (10.1109/TMTT.2017.2669988)
  DOI : 10.1109/TMTT.2017.2669988
• Channel models in the near field
  
  • Charaf Akl
  • Rodriguez G.
  , 2017.
• Adaptive Streaming of HEVC Tiled Videos using MPEG-DASH
  
  • Concolato Cyril
  • Le Feuvre J.
  • Denoual Franck
  • Mazé Frédéric
  • Nassor Eric
  • Ouedraogo Nael
  • Taquet Jonathan
  IEEE Transactions on Circuits and Systems for Video Technology, Institute of Electrical and Electronics Engineers, 2017. (10.1109/TCSVT.2017.2688491)
  DOI : 10.1109/TCSVT.2017.2688491
• Secret key generation scheme from WiFi and LTE reference signals
  
  • Kameni Ngassa Christiane L.
  • Molière Renaud
  • Delaveau François
  • Sibille Alain
  • Shapira Nir
  Analog Integrated Circuits and Signal Processing, Springer Verlag, 2017. Physical layer security has emerged as a promising approach to strengthen security of wireless communications. Particularly, extracting secret keys from channel randomness has attracted an increasing interest from both academic and industrial research groups. In this paper, we present a complete implantation of a secret key generation (SKG) protocol which is compliant with existing widespread Radio Access Technologies. This protocol performs the quantization of the channel state information, then information reconciliation and privacy amplification. We also propose an innovative algorithm to reduce the correlation between quantized channel coefficients that significantly improves the reliability and the resilience of the complete SKG scheme. Finally we assess the performance of our protocol by evaluating the quality of secret keys generated in various propagation environments from real single sense LTE signals, and real single and dual sense WiFi signals. (10.1007/s10470-017-0941-3)
  DOI : 10.1007/s10470-017-0941-3
• OpenCTMod: An Open Source Collaborative Matlab Toolbox for the Design and Simulation of Continuous-Time Sigma Delta modulators
  
  • Pham Dang-Kièn Germain
  • Jabbour Chadi
  , 2017. Simulating Continous Time (CT) Sigma Delta Modualors (SDM) is commonly done using block level systems such as Simulink which is a highly time consuming task even at system level. Therefore, the existing design tools for SDM are either discrete time oriented (Schreier toolbox) or proprietary (Ulm toolbox). In this work, we propose a new Matlab/C toolbox for the design of CT SDM. Simulation is based on state space representation thereby allowing to support most of the existing SDM architectures. Moreover, the main non-idealities of the main blocks are modeled (opamp DC gain, finite GBW, DACs mismatch, ISI and quantizer offset). Besides, thanks to the modular and open source approach for this toolbox, every user can easily implement additional features and include it. During the forum, designs and simulations for various architectures of CT SDM will be performed to demonstrate the accuracy and efficiency of the proposed toolbox. The collaborative aspect will be also shown.
• Reliability and deployment issues of network coding in wireless networks
  
  • Ageneau Paul-Louis
  , 2017. Even if packet networks have significantly evolved in the last decades, packets are still transmitted from one hop to the next as unalterable pieces of data. Yet this fundamental paradigm has recently been challenged by new techniques like network coding, which promises network performance and reliability enhancements provided nodes can mix packets together. Wireless networks rely on various network technologies such as WiFi and LTE. They can however be unreliable due to obstacles, interferences, and these issues are worsened in wireless mesh network topologies with potential network relays. In this work, we focus on the application of intra-flow network coding to unicast flows in wireless networks. The main objective is to enhance reliability of data transfers over wireless links, and discuss deployment opportunities and performance. First, we propose a redundancy lower bound and a distributed opportunistic algorithm, to adapt coding to network conditions and allow reliable data delivery in a wireless mesh. We believe that application requirements have also to be taken into account. Since network coding operations introduce a non negligible cost in terms of processing and memory resources, we extend the algorithm to consider the physical constraints of each node. Then, we study the interactions of intra-flow coding with TCP and its extension MPTCP. Network coding can indeed enhance the performances of TCP, which tends to perform poorly over lossy wireless links. We investigate the pratical impact of fairness issues created when running coded TCP flows besides legacy non-coded TCP flows. Finally, we explore two different ways to enhance the performance of MPCTP in wireless environments : running it over network coding, and implementing the coding process directly in MPTCP while keeping it fully TCP-compatible. (10.70675/cce07158z5598z4fdaz962ez0f24ea42fa34)
  DOI : 10.70675/cce07158z5598z4fdaz962ez0f24ea42fa34
• Implementing and Evaluating a Laughing Virtual Character
  
  • Mancini Maurizio
  • Biancardi Beatrice
  • Pecune Florian
  • Varni Giovanna
  • Ding Yu
  • Pelachaud Catherine
  • Volpe Gualtiero
  • Camurri Antonio
  ACM Transactions on Internet Technology, Association for Computing Machinery, 2017, 17 (1), pp.1-22. Laughter is a social signal capable of facilitating interaction in groups of people: it communicates interest, helps to improve creativity, and facilitates sociability. This article focuses on: endowing virtual characters with computational models of laughter synthesis, based on an expressivity-copying paradigm; evaluating how the physically co-presence of the laughing character impacts on the user’s perception of an audio stimulus and mood. We adopt music as a means to stimulate laughter. Results show that the character presence influences the user’s perception of music and mood. Expressivity-copying has an influence on the user’s perception of music, but does not have any significant impact on mood. (10.1145/2998571)
  DOI : 10.1145/2998571
• Video conference based on enterprise desktop grid
  
  • Sorokin Roman
  , 2017. There exist two classical and well-understood approaches to video processing tasks for videoconferencing. The first one is using a centralized Multipoint Control Unit (MCU). In the second approach, the video processing tasks are directly handled in endpoints. Performance is then restricted by device characteristics, especially in the case of mobile devices. In this thesis, we propose a third alternative approach. We propose a system, which distributes real-time video processing tasks on enterprise desktop grid. A dedicated Multi Attribute Decision Making method is designed in order to take into account the variety of attributes impacting Quality of Experience. A number of task distribution and redistribution algorithms are elaborated. We then test the proposed approach by means of simulation in order to study the impact of the main critical parameters. The proposed approach arises a question to which extent a PC can be used as a platform for media server and how CPU load affects the quality of provided video conference. We estimate a perceived quality of video streams in order to investigate CPU load influence. Also we elaborated algorithms, combining Cloud/Fog approach with different types of media servers, the result provides an optimized conferencing solution in the terms of cost for both provider and consumer as well as in terms of end user experience. Combining elaborated algorithms and architecture with experimentation results we conclude that proposed solution can be used as a novel approach to video conferencing problematic. (10.70675/4ef35b6ez2d1bz4017z8996z151761d6e5d5)
  DOI : 10.70675/4ef35b6ez2d1bz4017z8996z151761d6e5d5