Post-doc: Hybrid Beamforming schemes for downlink Sub-THz MIMO systems

Public establishment belonging to IMT (Institut Mines-Télécom), placed under the supervision of the Ministry of Economy, Finance and Industrial and Digital Sovereignty, IMT Nord Europe has three main objectives: providing our students with ethically responsible engineering practice enabling them to solve 21st century issues, carrying out our R&D activities leading to outstanding innovations and supporting territorial development through innovation and entrepreneurship. Ideally positioned at the heart of Europe, 1 hour away from Paris, 30 min from Brussels and 1h30 from London, IMT Nord Europe has strong ambitions to become a main actor of the current industrial transitions, digital and environmental, by combining education and research on engineering and digital technologies.

Located on two main campuses dedicated to research and education in Douai and Lille, IMT Nord Europe offers research facilities of almost 20,000m² in the following areas:

-              Digital science,

-              Energy and Environment,

-              Materials and Processes.

For more details, visit the School’s website : www.imt-nord-europe.fr

The position is vacant within the CERI SN, ARTS (Autonomous and Resilient System axis) axis. ARTS focuses on designing distributed and communicating systems, from IoT to fleets of robots (land and aquatic). These systems address key challenges for a sustainable industry and environmental monitoring by collecting on-site data. ARTS enhances these systems' security, resilience, and autonomy across multiple layers: from physical communication and signal processing to resource-efficient software architectures. Their work ensures interoperability, scalability, and context adaptability while addressing networking issues. This approach lays the groundwork for the distributed systems of tomorrow.

Sub-Terahertz (THz)-band (0.1-1 THz) communication is envisioned as a key wireless technology of the next decade. The sub-THz band will help overcome the spectrum scarcity problems and capacity limitations of current wireless networks, by providing an unprecedentedly large bandwidth which can enable applications including Terabit-per second backhaul systems, ultra-high-definition content streaming among mobile devices and wireless high-bandwidth secure communications.

However, several challenges remain. At sub-THz frequencies, the harsh channel conditions (strong obstruction losses) limit communication to line-of-sight (LoS) or slightly obstructed LoS scenarios. Such limitations can be compensated by means of using a large number of antennas, which results in large array gains. However, traditional techniques cannot be directly applied to the sub-THz band as they do not consider the specific radio-frequency (RF) impairments of sub-THz.

Hybrid beamforming [1] is expected to play a crucial role in enabling high data rates and reliable communication links over short distances, since it combines the advantages of analog and digital beamforming while mitigating their respective drawbacks. Additionally, power efficiency is a critical concern due to the high-power consumption of RF chains in power amplifiers, driven by the peak-to-average power ratio. Power-efficient schemes with spatial modulation techniques can address this issue by reducing power consumption while maintaining the same spectral efficiency. The application of spatial modulation (SM) techniques [2] in sub-THz communications has recently attracted substantial research interest.

REQUIRED PROFILE:

Objectives:

• Explore the state-of-the-art on hybrid beamformed multi-user MIMO schemes in sub-THz.
• Design hybrid beamforming schemes tailored to the characteristics of Sub-THz communication band, considering both Fully-Connected and Array of Sub-Array architectures. 
• Combine the proposed schemes with spatial modulation techniques to enhance the spectral efficiency.

[1] J. Tan and L. Dai, "THz Precoding for 6G: Challenges, Solutions, and Opportunities," in IEEE Wireless Communications, vol. 30, no. 4, pp. 132-138, August 2023

[2] M. D. Renzo, H. Haas and P. M. Grant, "Spatial modulation for multiple-antenna wireless systems: a survey," in IEEE Communications Magazine, vol. 49, no. 12, pp. 182-191, December 2011