DESCRIPTION :
The evolution of threats and the increasing speed of flying objects necessitate adapting to these new targets for identification, with the capability to track them across a wide field of view. To achieve this, active electronically scanned antennas must be more efficient and have the widest possible angular aperture.
Unfortunately, depending on the pointing angle of an electronically scanned antenna, and considering the radiation properties of its constituent intrinsic elements (radiation pattern varying with elevation angle), both the gain and the beamwidth tend to vary, making it difficult to maintain consistent performance at low elevation angles.
Scientific issues - Research Project positioning
Metasurface-based solutions provide undeniable flexibility in managing large angular deflections but still require optimization and further research into the composition of the metasurface.
* How can frequency dispersion of unit cells be managed (phase shift depends on unitcell length if the structure is non-resonant) using acceptably complex methods?
* How to counter beam impacts (dispersion, spreading, splitting) for large pointing angles? (Cross-optimization of planar array antenna / metasurface dome)
* How to prevent gain losses in azimuth due to the potentially non-optimal behaviour of the radome in those directions?
* What happens when a non-orthogonal wavefront interacts with the surface? (e.g. presence of jammers, oblique incidence).
Lab-STICC and Thales are collaborating on these research issues and have notably contributed to evaluating and utilizing RF 3D printing technologies in radar contexts, both for radomes and optimized primary source solutions.
As part of this PhD, the work will focus particularly on the joint optimization of the RF lens dome with the sub-assemblies of the multi-phase planar array, which should ideally be preserved to leverage mature amplitude/phase control technologies.
Lab-STICC is especially developing inverse multi-scale modeling methods that infer the electromagnetic properties of a given volume (multi-dielectric and/or with metallic inserts). These mixed simulation approaches will enable the optimization of the intermediate focusing component, such as the RF lens dome, from a target angular deflection zone and a set of amplitude/phase-controlled primary sources.
Research Methodology & Timeline
The research project will unfold in the following key phases:
Year 1: State of the Art - Scientific Positioning and Identification of New Concepts
· Literature review on angular broadening techniques or devices (dielectric dome or sub-wavelength RF lenses)
· Highlight the issue of directive degradation for large deflection angles
· Familiarization with tools & technologies
· Development of initial experimental prototypes
Year 2: Theoretical Phase - Modeling - Formalization of the Proposed Technical Solution
· Option 1: A planar multi-source array is considered
· Option 2: Potential use of distinct oriented multi-source sectors
Year 3: Advanced Prototypes
· Characterization of the antenna array in both transmission and reception, including the antenna array + dielectric dome assembly
· Impact analysis
· Reflection on the limitations of this approach in the context of an embedded monopulse radar
Supervision conditions of the thesis
The thesis will be supervised by a multidisciplinary team of academics and industrial professionals:
· Christian Person, Professor - Lab-STICC/IMT Atlantique, Thesis Director
· Clément Henry, Associate Professor - Lab-STICC/IMT Atlantique, Academic Cosupervisor
· Julien Deza, RF Systems Engineer - Thales LAS, Industrial Co-supervisor
· Thomas Merlet, Technical Manager for CIFRE Theses at THALES LAS Elancourt - Thales LAS, Industrial Co-supervisor
These partners have long-standing collaborative experience. Thales LAS and Lab-STICC work together within the joint laboratory LATERAL, tackling a variety of research topics (radar, communications, image processing, etc.). The candidate will work alongside several collaborators (PhD students, interns, postdocs, academic researchers, R&D engineers) in a dynamic and collaborative work environment.
Weekly videoconferences between Lab-STICC and Thales will ensure regular progress tracking. Quarterly meetings involving all joint lab members will allow the PhD work to be reviewed and steered in light of mutual scientific and application interests.
Code d'emploi : Ingénieur Radio-Fréquences (h/f)
Domaine professionnel actuel : Ingénieurs, Projeteurs et Techniciens Électricité
Niveau de formation : Bac+5
Temps partiel / Temps plein : Plein temps
Type de contrat : Contrat à durée déterminée (CDD)
Compétences : Impression en 3D, Python (Langage de Programmation), MATLAB, Radio-Frequency Identification, Hfss, AngularJS, Anglais, Adaptabilité, Sens de la Communication, Esprit d'Équipe, Motivation Personnelle, Recherche, Amplitudes, Antenne, Dispersion (Optique), Diélectrique, Électromagnétisme, Traitement d'Image, Méthodologie de Recherche, Approche Pluridisciplinaire, Sciences Physiques, Réalisation de Prototypes, Recherche et Développement, Simulations, Radar, Littérature, Analyse d'Impact, Vidéoconférence, Sous-ensembles
Courriel :
christian.person@imt-atlantique.fr
Type d'annonceur : Employeur direct
