Scientific direction Development of key enabling technologies
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PhD : selection by topics

Technological challenges >> Communication networks, IOT, radiofrequencies and antennas
12 proposition(s).

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Autonomous network management solution for deterministic networks using Artificial Intelligence (AI) techniques

Département Intelligence Ambiante et Systèmes Interactifs (LIST)

Laboratoire Systèmes Communiquants

01-02-2021

SL-DRT-21-0178

siwar.benhadjsaid@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

The objective of the thesis is to explore and evaluate the gain that could bring the Artificial Intelligence (AI) techniques to the network management solutions for deterministic networks. The goal is to help deterministic networks to ensure the preservation of the quality of service (QoS) during the routing of end-to-end data flow no matter what changes are made to the network. This will allow to design an autonomous network management solution that is able to configure deterministic networks in the most appropriate way and adapt the configuration when needed (e.g. new terminal connecting to the network, unexpected high latency for certain critical flows, change of the topology caused by the reorganization / reconfiguration of components of the production chain in the factory etc.). This solution will use artificial intelligence methods to learn from experience the conditions that lead to non-compliance with application flow requirements (high latency, low bandwidth, etc.). Learning takes place to recognize, upstream, the situations that may lead to non-compliance with the constraints of application flows and also to predict the effects of changes in input data (new terminal, reorganization of the plant, etc.) on the level of QoS provided to flows in transit. Based on such knowledge, the solution will anticipate QoS degradation situations and, consequently, will decide and push the adequate network reconfiguration which will make it possible to respect the constraints associated with each application flow.

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Distributed resource allocation for meshed networks of mobile users in shared spectrum

Département Systèmes (LETI)

Laboratoire Sans fils Haut Débit

01-09-2021

SL-DRT-21-0186

mickael.maman@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

In future 5G wireless networks, it is imperative to easily deploy and manage a private network of mobile users such as a fleet of vehicles or UAVs. The objective of this thesis is to define a distributed resource allocation for mesh networks of mobile users in the shared spectrum through resource pooling (time/frequency) and efficient management of directional antenna beams. While existing studies focus on maximizing the performance of static backhaul multi-beam mesh networks, we are interested in collaborative local/distributed learning between mobile users. The first step of this thesis will be to integrate a realistic model of sub 6-GHz and/or mmW directional antennas in a network simulator. A trade off between the spatiality of the directivity, the antenna efficiency and the complexity of the algorithm will be made for point-to-point and point-to-multipoint communications. Moreover the antenna configurations will be contextualized between the communication, discovery or tracking phases. The second step of this thesis will concern the design of the distributed resource allocation protocol during different stages of the network life: deployment, self-optimization and self-healing. A trade-off will be made between the type and latency of antenna (re)configuration, the accuracy of beam alignment, the channel coherence time for mobile users (volatile connectivity) and the convergence time of the scheduling.

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Wideband mmW receiver architectures based on innovative modulation schemes

Département Systèmes (LETI)

Laboratoire Architectures Intégrées Radiofréquences

01-03-2021

SL-DRT-21-0216

joseluis.gonzalezjimenez@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

Existing telecommunication and data communication networks are evolving towards extremely high capacity and data-rate connections that will require innovative transceiver architectures. For wireless data links, beyond 5G and 6G and systems will be required in the next 5 to 10 years able to provide 100Gb/s or higher data rates by efficiently using the wide spectrum available at millimeter-wave (mmW) or sub-THz frequencies. Traditional transceiver architecture that have been used in the past may result too power consuming or simply not performant enough to respond to this challenge. The LETI research institute has been conducting research during the lasts year in the field of innovative modulations schemes and transceiver architectures trying to respond to the above-mentioned high data-rate in wireless environments considering the limitation imposed by existing electronic devices required to build the transceivers. This thesis subject will explore the practical implementation of circuits based on innovative modulation schemes and architectures for high-speed, large-bandwidth, imperfection resilient mmW receivers for beyond 5G and 6G telecommunication applications and other high data-rate wireless communications applications.

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Millimeter Wave Short Range RadCom

Département Systèmes (LETI)

Laboratoire Architectures Intégrées Radiofréquences

01-09-2021

SL-DRT-21-0258

cedric.dehos@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

Mmw transceiver chips for high data rate, short range communication should be integrated soon in most mobile devices as contacless connectors. The wide bandwidth of these mmw transceiver may be used for fine resolution proximity radar, gesture recognition, biometric identification or Human Machine Interface. The thesis will investigate the possibility of slightly modifying the RF transceiver architecture to get the double feature of radar and communication in the same low cost and low power chip. The non-coherent communication architecture may evolve towards IR-UWB or FM-CW radar, with impact on the receiver complexity and radar performance. The PHD will evaluate the different alternatives, considering integrated low power radar processing and Artificial Intelligence embedded in MCU for analysis and classification.

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Near-field focusing techniques in inhomogenous media at millimiter wave

Département Systèmes (LETI)

Laboratoire Antennes, Propagation, Couplage Inductif

01-10-2021

SL-DRT-21-0378

antonio.clemente@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

In a huge number of applications such as wireless power transfer (WPT), microwave imaging, industrial control, etc., it is required to collimate, form or focus the electromagnetic radiation in a specific region of the space. Sometimes, this region could be located in the near-field region of the radiating element or surface. In this case, it is referred to as a near-field focused system. With the development of the future ?Beyond 5G? and 6G communication systems, the necessity to focus the radiating beam in the near-field region could be also required in the case of the reconfigurable intelligent surfaces (RIS). These kind of devices, when composed of reconfigurable elements, can be deployed to manipulate the electromagnetic waves and dynamically control and adjust the properties of the propagation channel. Eventually, near-field focusing could be also applied to future medical imaging systems at microwaves. These devices require focusing and collimating the electromagnetic energy in the human body tissues in order to diagnose, monitor and/or treat specific pathologies. In this context, near-field focusing can be used to improve the resolution of the imaging system by optimizing the energy transfer/transmission. The first objective of this thesis is to develop specific numerical tools for the synthesis, design and optimization of near-field focused systems in non-homogeneous media. These techniques will be developed by considering the electromagnetic properties of the media. The synthesis of the aperture field will be done considering modal expansion of the field and the potential vectors theory. After this phase, the synthesis and optimization procedures will be used to design a near-field focused antenna system operating at millimeter and/or sub-THz frequencies (30 - 300 GHz). These antennas will be manufactured and characterized in near-field test ranges. Measurements will validate the developed models for flat radiating apertures in specific scenarios. The possibility to perform measurements in a real applicative context (e.g. cancer detection) will be also considered.

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Deep Wireless Localization based on Artificial Intelligence for Challenging Environments

Département Systèmes (LETI)

Laboratoire Communication des Objets Intelligents

01-10-2021

SL-DRT-21-0398

benoit.denis@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

Various low-cost wireless localization technologies ans standards have emerged in recent years (e.g. UWB/IEEE802.15.4z standard, GPS RTK, cellular radio in millimeter wave bands...), fulfilling the needs of a variety of location-based applications and services (e.g., sustainable mobility and intelligent transport systems, smart cities, industry 4.0, cyber-security, etc.). However, despite the good theoretical performances of these systems, radio obstructions and multipath propagation degrade in practice both localization accuracy and continuity (e.g. vehicular navigation in urban canyons, indoor assets or pedestrians localization in dense industrial environments...). In the frame of these new PhD investigations, we propose to evaluate and demonstrate the promising potential of Artificial Intelligence, and more specifically, of advanced (deep) machine learning tools, to assess the richness and the complexity of received radio signals from a specific localization standpoint. Typically, one aim would be to benefit from the « hidden » location-dependent information contained in received mulitpath multi-link signals under user mobility. In constrast to conventional correction approaches based on a priori parametric models, which are most often too simplistic and hard to calibrate, we will thus consider learning and generalizing the fundamental non-linear relationships linking key location-dependent features (i.e., extracted out of high-dimension input received signals) and localization descriptors (e.g., relative/absolute position, speed, orientation, visibility conditions?). Accordingly, so-called « deep » localization strategies will then be developped, enabling the prediction, detection and/or completion of erroneous/missing location attributes, directly in terms of positioning and tracking at the system level (i.e., without requiring intermediary and independent link-wise correction steps). The designed learning architectures and localization approaches will be fed and validated by means of large radio databases, including both field measurements collected with real radio devices and synthetic data based on determinsitic prediction tools (e.g., ray-tracing).

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New physical layer on millimeter wave band for 5G-NR IoT

Département Systèmes (LETI)

Laboratoire Communication des Objets Intelligents

01-10-2021

SL-DRT-21-0410

valerian.mannoni@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

A new 5G air interface is to be designed, in order to address good reliability and acceptable latency service for IoT use cases not addressed yet by Cellular IoT technologies. This new 5G air interface is the subject of a study item in 3GPP release 17 and has been called NR_REDCAP (Reduced Capability NR devices). The ability to operate NR-Light on millimeter wave band is seen as required for Industry 4.0 applications and attractive for private networks due to its limited range and high spatial reuse. The objective of the PhD thesis is then to propose and investigate a new physical layer on millimeter wave band for 5G-NR IoT meeting the above challenges. The expected results are: - A better understanding of challenges and key enablers of 5G NR in millimeter wave band - Proposal of a new physical layer for 5G-NR IoT with the associated MIMO scheme - Proposal and study of the multiple access scheme based on MIMO - Identification and assessment of key NR-Light enablers in millimeter wave band to fulfill these requirements and reach the reduced complexity and cost target of NR-Light UEs while mitigating the performance degradation of such complexity reduction, for example coverage degradation.

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Dispersion-engineered metalenses for high-performance low-profile antennas and extreme wave manipulation

Département Systèmes (LETI)

Laboratoire Antennes, Propagation, Couplage Inductif

01-10-2021

SL-DRT-21-0638

francesco.fogliamanzillo@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

The performance of conventional antenna architectures, e.g. phased arrays and reflectors, is limited by inherent trade-offs among bandwidth, efficiency, scan range and size. Disruptive concepts are necessary to address the demanding requirements arising in novel applications such as satellite and 5G communications, and high-resolution imaging. Metasurfaces (MSs) are electrically thin arrays of subwavelength scatterers and have recently emerged as a promising concept to attain unprecedented antenna performance and functionalities. The subwavelength periodicity of a MS offers an extremely fine control on the aperture fields and, by virtue of Huygens' principle, the possibility to perform a wide range of transformations of the incident field. However, there is a lack of advanced models and synthesis methods for the design of anisotropic MSs. Moreover, the bandwidth of most MS antennas is often too narrow due to frequency dispersion. This thesis aims to provide a mathematical framework for the analysis and design of MS lenses and to demonstrate groundbreaking ultralow-profile antenna systems comprising a primary source and a metalens realized with a few cascaded layers. The metalens will be modeled as an effective bianisotropic medium, exhibiting coupled responses to electric and magnetic fields. Specific synthesis procedures will be developed to engineer the frequency dispersion of a large metalens and to tailor its refractive index as a function of the incident angle of the impinging wave. These tools will be exploited for the design of two demonstrators at microwave frequencies: (i) a high-gain antenna achieving extremely high aperture efficiency (>70%) and large fractional bandwidth (>15%); (ii) a thin meta-radome for extending the scan range of a phased array beyond the state of the art (±75°) while preserving high broadside efficiency. At least one demonstrator will be prototyped using low-cost fabrication processes, such as printed circuit board and additive manufacturing, and experimentally characterized.

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Integration of RF switches based on chalcogenide phase change materials

Département Composants Silicium (LETI)

Laboratoire Composants Radiofréquences

01-10-2021

SL-DRT-21-0754

bruno.reig@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

In order to meet the future needs of 5 / 6G cellular networks and SATCOM satellites, It is necessary to develop RF systems with higher performances and agility. In this context, new RF switch technologies based on chalcogenide phase change materials have gain strong attention as they promise to offer disruptive solutions to realize miniature and high speed reconfigurable RF circuits with low power consumption and that can be easily integrated with CMOS circuits. The objective of the PhD thesis is therefore to develop a new RF switch technology based on chalcogenide materials for future wireless telecommunications systems. The requested work is multidisciplinary and will be carried out in close collaboration between three division of the CEA-LETI bringing their expertise on the synthesis of new materials, on the technological integration of innovative RF components and on the development of advanced electronic functions. The PhD student will define the main specifications of the switches for the targeted applications and will seek to identify the key properties required for the phase change material. He will evaluate various alloys of chalcogenide materials and will develop a technological flow for switches in order to optimize the reliability and the performance of the component. Finally, he will design innovative RF circuits and he will study the influence of design parameters on the overall system performance within an application demonstrator.

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Beyond Shannon with Semantic Communications for 6G Networks and Services

Département Systèmes (LETI)

Laboratoire Sans fils Haut Débit

01-06-2021

SL-DRT-21-0844

emilio.calvanese-strinati@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

The future of mobile communications will be characterized by ubiquitous connection availability, very dense networks in terms of number of users and access points, ultra-low latency, very high bandwidth, and energetic efficiency. The 6G network revolution will be enabled by cutting-edge technological innovations, concerning millimeter-wave radio communications, baseband and RF architecture, resources virtualization, and the native support of artificial intelligence. The main goal of this PhD investigation is to motivate the need, in the design of new 6G networks, for a paradigm shift from the mainstream research, which basically builds on Shannon's framework, towards semantic and goal-oriented communications. A game-changing idea consists in exploring semantics in wireless communications to go beyond the common Shannon paradigm of guaranteeing the correct reception of each single transmitted packet, irrespective of the meaning conveyed by the packet. The idea is that, whenever communication occurs to convey meaning or to accomplish a goal, what really matters is the impact that the correct reception/interpretation of a packet is going to have on the goal accomplishment. The PhD candidate will explore the very recently-proposed and innovative concept of wireless semantic communications. The work will focus on the design of algorithms for a proactive and dynamic implementation of semantic communications, targeting the optimal end-to-end efficiency of the joint allocation of the above mentioned resources. Distributed learning techniques will be investigated and proposed.

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Mmwave multi-static scattering model for imaging and radar application

Département Systèmes (LETI)

Laboratoire Antennes, Propagation, Couplage Inductif

01-09-2021

SL-DRT-21-0895

raffaele.derrico@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

This PhD program is proposed within the framework of CEA-LETI's R&D activities in the field of wireless and radar transmission technologies using millimeter waves. These technologies, already used in automotive radar applications and envisaged in a future deployment of 5G, exploit very wide bands. In the long term, the convergence between communication and radar (RADCOM) will make it possible to envisage new applications of precise imagery, reconstruction and "sensing" of the environment. The use of multi-antenna millimeter wave technologies, compacted in a reduced volume, will allow new capabilities in terms of temporal precision and angular resolution. However, the development of these new approaches requires a precise knowledge of the targets backscattering seen by the different antennas. In particular, in short-range applications, the concept of Radar Cross Section (RCS) could be no longer applicable and may require near-field modeling. The objective of this thesis is to develop a millimeter wave backscattering model of objects for proximity radar and multi-sensor imaging applications. The study will begin with a state of the art concerning multi-antenna radar systems and the implementation of a (simplified) propagation model. Then, the PhD student will develop a test bench dedicated to characterization. It will provide composite reflectivity models for different objects and for the human body. This modelling could be eventually based on a point cloud representation that will be combined with artificial intelligence (AI) approaches. The PhD student will be part of the Antenna, Propagation and Inductive Coupling Laboratory at CEA-LETI, in Grenoble (France). He/she will benefit of the state of the art facilities (channel sounders, emulator, OTA setup, and electromagnetic simulator). Application: The position is open to outstanding students with Master of Science, ?école d'ingénieur? or equivalent. The student should have specialization in the field of telecommunications, radar, microwave and/or signal processing. The application must necessarily include a CV, cover letter and grades for the last two years of study.

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Mmwave OTA testing based on field synthesis for 5G/6G systems

Département Systèmes (LETI)

Laboratoire Antennes, Propagation, Couplage Inductif

01-09-2021

SL-DRT-21-0942

raffaele.derrico@cea.fr

Communication networks, IOT, radiofrequencies and antennas (.pdf)

This PhD program is proposed within the framework of CEA-LETI's R&D activities in the field of wireless transmission technologies and 5G / 6G systems using millimeter waves. In these networks a large number of antennas will be used in order to increase the datarate and be able to serve a large number of users. The radio system performance will depend on both R&D choices and deployment conditions. The objective of this thesis is to propose Over-the-Air (OTA) test methodologies in a controlled environment, which makes it possible to reproduce realistic propagation conditions and thus be able to evaluate the performance of future communications systems, without carrying out long environmental measurement campaigns. real. To this purpose, a methodology based on fading emulator combined with intelligent surfaces is considered to reproduce the multi-path channel. The study will begin with a state-of-the-art model of the 5G propagation channel and OTA methodologies. Then the PhD student will propose a theoretical modeling of the testbed based on an analysis of spherical modes and an optimization for planar wave synthesis. Then an experimental implementation of the proposed methodology will be realized. The PhD student will be part of the Antenna, Propagation and Inductive Coupling Laboratory at CEA-LETI, in Grenoble (France). He/she will benefit of the state of the art facilities (channel sounders, emulator, OTA setup, and electromagnetic simulator). Application: The position is open to outstanding students with Master of Science, ?école d'ingénieur? or equivalent. The student should have specialization in the field of telecommunications, radar, microwave and/or signal processing. The application must necessarily include a CV, cover letter and grades for the last two years of study.

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