Energy- and Spectrally-Efficient sub-THz Transmitter Array Towards Indoor 6G Infrastructure

Project Information

ENSPEC6G

Grant agreement ID: 101062272

DOI

10.3030/101062272

Project closed

EC signature date 14 June 2022

Start date 4 July 2022

End date 3 July 2024

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 148 478,40

Coordinated by

SABANCI UNIVERSITESI
Türkiye

Periodic Reporting for period 1 - ENSPEC6G (Energy- and Spectrally-Efficient sub-THz Transmitter Array Towards Indoor 6G Infrastructure)

Reporting period: 2022-07-04 to 2024-07-03

Summary of the context and overall objectives of the project

The ENSPEC6G project addresses the rising demand for faster, more energy-efficient communication systems as we move towards 6G infrastructure. With the growing number of internet users and IoT devices, future networks need to handle significantly higher data rates while minimizing environmental impact. Sub-terahertz (sub-THz) frequencies offer promising solutions to meet these demands, but their adoption poses challenges due to higher power consumption and complex thermal management requirements. ENSPEC6G is focused on developing a sustainable, high-performance sub-THz transmitter array designed to maximize both data throughput and energy efficiency.
The project’s main objective is to create a dual-polarization transmitter array with world-class efficiency and high data rates, enabling sustainable and reliable 6G communications. To achieve this, ENSPEC6G aims to innovate across four areas: designing a high-efficiency transmitter array, developing advanced modulation schemes, implementing low-loss phase shifting for effective beam steering, and refining compact, dual-polarization antenna designs. By meeting these goals, ENSPEC6G contributes to building digital infrastructure that aligns with EU priorities for environmental sustainability, technological leadership, and digital innovation.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The project has made substantial progress in developing advanced sub-THz communication components, focusing on design, simulation, and optimization across multiple work packages. Key achievements can be summarized in four items.
1. High-performance modulators were designed to deliver improved bandwidth and energy efficiency, meeting high data rate requirements.
2. A low-loss phase shifter using THz surface waveguides was developed in collaboration with TOBB University. This innovation enhances beam-steering capabilities at high frequencies, surpassing conventional CMOS designs.
3. The team developed a voltage-controlled oscillator (VCO) for sub-THz frequencies and used machine learning (ML) to create a transistor model that increases design accuracy and reduces errors.
4. Multiple antenna types were optimized for single-polarization performance, achieving high radiation efficiency and preparing for dual-polarization implementation in the transmitter array.
These achievements bring ENSPEC6G closer to creating a high-performance, sustainable sub-THz communication system, positioning the project to make impactful contributions to 6G infrastructure.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

ENSPEC6G has delivered significant advancements in sub-THz communications, setting new benchmarks in efficiency and spectral performance for 6G applications. Key innovations include:
1. The critical sub-blocks for a highly efficient transmitter array, capable of supporting dense 6G networks while reducing environmental impact, were designed with promising results. For instance, more than 40dB On/Off ratio is achieved for ultrawideband modulators.
2. A new phase shifter based on THz surface waveguides, reducing signal loss and power consumption in high-frequency communications, specifically for 300GHz frequency region, and with losses ten-fold less than what can be achieved with conventional topologies.
3. An initial ML/AI-based transistor model streamlines sub-THz circuit design, enhancing accuracy and reducing development time, which is critical for rapid innovation in 6G. Very accurate measurement to NN models are developed for DC conditions of the transistors.
4. Antenna designs are optimized for high-efficiency transmission around 300GHz region as on-chip, with more than 0dBi antenna gain, which is promising considering the substrate and metallization losses at sub-THz.
To ensure the broader adoption of these technologies, the project recommends further validation through demonstration projects and integration technology development, support for standardization efforts, and collaboration with industry to accelerate commercialization.