Doctoral course - Emerging Technologies and Tools for Wireless Systems: Programmable Metasurfaces

Lecturer: Prof. Marco DI RENZO's homepage | L2S Paris-Saclay (centralesupelec.fr)

Credits and assignments

The course is passed by solving project assignments including calculus problems and simulation tasks with Matlab => 3 ECTS.

An optional assignment: Solution to an individual research problem. The research problem can be proposed by the student, or the student can select from a set of problems formulated by the teachers. Solution requires problem solving, performance assessment via simulations, and reporting the results in a format of a scientific manuscript or publication draft. => 5 ECTS in total (i.e., 2 extra credits).

Target audience and registration

The course is meant for doctoral students and senior master students. (Postdocs also welcome.) Basic knowledge of wireless communications theory and radio frequency engineering is required.

Registration in Peppi portal for the course 521186S-3001 Modern Topics in Telecommunications and Radio Engineering 16: Emerging Technologies and Tools for Wireless Systems: Programmable Metasurfaces 3 - 5 op (521186S-3001 Tietoliikenne- ja radiotekniikan ajankohtaisia aiheita 16: Emerging Technologies and Tools for Wireless Systems: Programmable Metasurfaces 3 - 5 op). In case of no study right and interested in following the lectures, you can join the lectures in room TS128.

Background, motivation, and scope

The history of wireless communications started with understanding fundamental electric and magnetic phenomena, as well as the related experiments and inventions that were carried out during the last half of the eighteenth century and the first decades of the nineteenth century. Wireless communications (often, just wireless) are defined as and are characterized by the transfer of information between two or more points without the need of using an electrical conductor as the medium to perform the transfer. The most common wireless technologies use electromagnetic waves. Thanks to the development and wide adoption of five wireless telecommunication standards and the recently started activities on the sixth generation of wireless systems and networks, we do live in a world of electromagnetic waves.

Wireless connectivity is indeed regarded as a fundamental need for our society. Between 2020 and 2030, it is forecast that the data traffic of the global Internet protocol (IP) will increase by 55% each year, eventually reaching 5,016 exabytes, with data rates scaling up to 1 Tb/s. Besides supporting very high data rates, future wireless networks are expected to offer several other heterogeneous services, which include sensing, localization, low-latency and ultra-reliable communications. Fifth-generation (5G) networks are, however, not designed to meet these requirements. As the demands and needs become more stringent, in fact, fundamental limitations arise, which are ultimately imposed by the inherent nature of wireless operation. More precisely, small cells, massive MIMO (multiple-input multiple-output), millimeter-wave communications are three fundamental technologies that will spearhead the emergence of 5G wireless networks – Their advantages are undeniable. The question is, however, whether these technologies will be sufficient to meet the requirements of future wireless networks that integrate communications, sensing, and computing in a single platform.

After five generations of wireless networks, in fact, the improvement that can be expected without new breakthrough technologies are limited. More precisely, the sixth generation (6G) of communication networks is indeed envisioned to require a new architectural platform that performs joint communication, sensing, localization, and computing, while ensuring ultra-high throughput, ultra-low latency, and ultra-high reliability, which need to be flexibly customized in real-time. In this context, promising but not well understood technologies are emerging, which include reconfigurable intelligent surfaces, holographic (continuous-like surfaces) MIMO, integrated sensing and communications. Also, wireless communication systems are moving towards high frequency bands and the density of network elements and surfaces will massively increase.

Therefore, new communication models and analytical tools will be needed to analyze the ultimate performance limits and to optimize future wireless networks with a dense deployment of network elements. It is believed that the interplay of electromagnetics, physics, communications, statistical signal processing, optimization theory, and machine learning will be instrumental in this context. This course will introduce the attendees with the emerging technology referred to as programmable metasurfaces, offering a comprehensive understanding of their operation, as well as it will provide the attendees with the analytical tools for analyzing their performance and for optimizing their operation and deployment. Special focus will be put on reconfigurable intelligent surfaces and holographic MIMO. The rationale and the operation of these technologies will be discussed and then the analytical tools for their analysis and optimization will be presented, which merge electromagnetic theory, information theory, and signal processing.

Lecture contents

Day 1 – Tue 28 May

Smart radio environments

Reconfigurable intelligent surfaces (RISs)

Communication models for RISs and performance evaluation

Day 2 – Wed 29 May

Channel estimation and optimization for RISs

Surface electromagnetics for programmable surfaces

Electromagnetically consistent models for RISs: Multiport network theory

Day 3 – Thu 30 May

Holographic surfaces/MIMO for wireless communications

Spatial multiplexing in line-of-sight MIMO

Recent advances: Stacked intelligent metasurface (SIM) and flexible metasurface (FIM)