PhD Reconfigurable metasurfaces for Radar Cross Section (RCS) control

Introduction

In the last decade, metamaterials and metasurfaces have received a great attention of the scientific community.  Concepts have been developed in a very wide range of the EM electromagnetic spectrum ranging from microwaves up to the infrared and visible frequencies.

Typically, microwaves metasurfaces consist of a dielectric substrate (with or without a metallic ground plane, depending on their operation in reflection or in transmit) with on top a lattice of sub-wavelength metallic scatterers, which can induce an abrupt variation of the electrical parameters of the impinging wave (phase, polarization, amplitude). Thanks to this property, metasurfaces can be very thin structures (compared to the wavelength of operation), which can perform an accurate manipulation and control of electromagnetic wavefronts. For example, they can control the radiation pattern, and the polarization of the scattered/reflected fields. Alternatively, they can convert the impinging wave into a guided wave inside the metasurface itself or vice versa, therefore operating as an antenna.

Objective

The main objective of this PhD research project is the development of reconfigurable metasurfaces for Radar Cross Section (RCS) control. This will include the development of an advanced and effective framework for the design of such structures, and also an experimental validation of the theoretical design and a demonstration of the technology.

Once integrated on platforms or infrastructures, such surfaces can control the scattering/reflection of an impinging electromagnetic wave generated by a radar. Furthermore, thanks to their reconfigurability, which allows changing the electromagnetic response of the metasurface through properly chosen reconfigurability mechanisms, it is possible to realize intelligent adaptive systems. Such systems, controlled by trained Artificial Intelligence (AI) algorithms, can react and adapt to different operational conditions (different radar illumination directions, movement of the platform, frequency hopping of the radar, different backgrounds, etc.). This allows also the implementation of different operational modes, which can be used to deceive the detection system in several different ways, offering higher immunity to possible countermeasures.

Main research questions

• Accurate and efficient modelling/design frameworks. One important activity of this project will be the development of an accurate and computationally efficient framework for the design of metasurfaces. The main purpose will be to avoid full dependence on commercial electromagnetic modelling software tools and go beyond their typical limitations when dealing with structures that are large in terms of the wavelength of operation and that contain many sub-wavelength features. This framework will considerably reduce the design time (from specs to final layout).
• Reconfigurability technology. Reconfigurability can be realized using different technologies, e.g. lumped electronic components (e.g. diodes), integrated semiconductor switches, micro electromechanical switches (MEMS), or integrated optical switches. Each of these different technologies have their own advantages and disadvantages. During the PhD, an assessment of these different technologies will be performed, and a final selection will be made for the experimental validation.
• Concept scalability to large surfaces. Other very important questions that will be addressed are:
• what is the maximum dimension required for the RF metasurface to provide an effective RCS reduction of the platform to which is applied?
• What is the most effective use of such metasurfaces (reducing the backscattering to the radar, jamming, active reflection cancellation)?
  In any case, it is required that the technology is scalable to large surfaces, with reasonable costs and accurate manufacturing processes and compatible with the requirements imposed by the integration on real platforms.

• Adaptive control of reconfigurable metasurfaces (optional and performed in cooperation with TNO staff). For a full exploitation of a reconfigurable metasurface, it is important to couple it to a control algorithm that can reconfigure the structure to react in an adaptive way to different operational conditions, and to switch between different operational modes.

PhD execution

The PhD project, which will be associated with the Technology University of Eindhoven, under the supervision of Prof. Dr. Giampiero Gerini (Electromagnetics Group - Electrical Engineering), will be executed in the Electromagnetic Signatures and Propagation Department, in cooperation with the Optics Department (Delft), of the Netherlands Organization for Applied Scientific Research (TNO). The PhD student will actively cooperate with TNO staff.

A meaningful job in a dynamic and ambitious university, in an interdisciplinary setting and within an international network. You will work on a beautiful, green campus within walking distance of the central train station. In addition, we offer you:

• Full-time employment for four years, with an intermediate evaluation (go/no-go) after nine months. You will spend 10% of your employment on teaching tasks.
• Salary and benefits (such as a pension scheme, paid pregnancy and maternity leave, partially paid parental leave) in accordance with the Collective Labour Agreement for Dutch Universities, scale P (min. €2,901 max. €3,707).
• A year-end bonus of 8.3% and annual vacation pay of 8%.
• High-quality training programs and other support to grow into a self-aware, autonomous scientific researcher. At TU/e we challenge you to take charge of your own learning process.
• An excellent technical infrastructure, on-campus children's day care and sports facilities.
• An allowance for commuting, working from home and internet costs.
• A Staff Immigration Team and a tax compensation scheme (the 30% facility) for international candidates.