6G-REFERENCE will contribute to the European leadership in microelectronic solutions for 6G communication and sensing infrastructure by developing hardware enablers for densified cell-free deployments.
The 6G haRdware Enablers For cEll fRee cohEreNt Communications & sEnsing (6G-REFERENCE) project targets radio unit hardware innovations enabling 6G densely distributed systems for high data rates and sensing. 6G networks should include integrated sensing and communications, from chemical and physical sensing to localisation and positioning.
To allow for flexible deployment, optical fibre access cannot be taken for granted and may just be available for a few radio unit access points. Synchronisation in frequency and time over the air then becomes a key challenge. Improvements in data capacity are wanted, while also supporting distributed sensing functionality towards the full internet of sense, where machines and robots can sense the environment through physical and chemical sensors, as well as integrating full radar capabilities, using the same hardware.
Realising all this functionality in practical hardware with low complexity, cost, and power consumption is a key challenge; the same hardware solutions should be reused for sensing and communications to achieve sustainable radio design. The 6G-REFERENCE consortium believes this may be possible by exploiting the cm-wave 10- 15GHz spectrum.
Hence, this project has five goals:
- Transceiver cm-wave radio frequency hardware innovations to address the data capacity and scheduling challenge of distributed multiple-input multiple-output systems.
- Novel solutions for accurate over-the-air frequency, phase and time synchronisation. This would not only support high-capacity data rate communication but may also enable high-resolution timing, enabling accurate localisation, positioning and sensing.
- New RF and antenna components providing extended spatial and frequency domain selective capabilities at reduced complexity, cost, and energy consumption.
- Hardware integrated circuit solutions with low complexity, low cost, and low power consumption. Sustainable radio design by using the same chips for communications and sensing, from physical and chemical to radar.
- Coexistence with existing services in the 10- 15GHz range, which is targeted since it not only provides new spectrum opportunities but also efficiently balances the benefits and drawbacks of sub-6GHz and mm-wave solutions. A rather unique feature of 6G-REFERENCE is the focus on frequency range 3 (FR3), which has already received a strong industrial interest, including a study item in 3GPP.
Use cases
In urban areas, 6G will need to rely on a sustainable solution to cope with the ever-increasing traffic demands and population densification, while providing disruptive capabilities like the materialisation of the internet of things. The solution envisioned by 6G-REFERENCE consists of ultra-dense cell-free deployments for joint coherent communications and sensing at cm-waves, which balance the benefits of sub-6GHz (e.g. reduced pathloss) and mm-wave (e.g. wide bandwidth) ranges.
These systems face five fundamental challenges:
- The need for accurate synchronisation among distributed radio units.
- Fronthaul data distribution.
- Integration of sensing capabilities.
- Low complexity/cost/consumption radios; and
- Coexistence with other services.6G-REFERENCE will develop integrated circuit and antenna component solutions addressing all of them.
Frequency/time synchronisation circuits will leverage recent innovations and explore new architectures with faster synchronisation. Efficient full duplex fronthaul data distribution among cascaded radio units will be explored, while also enabling integrated monostatic radar sensing. Besides these, on the sensing domain, 6G-REFERENCE will explore environmental sensors integrated in the antenna estate, reuse the synchronisation framework for accurate localisation, and develop new antenna array solutions building on recent innovations in modulated arrays.
Finally, dynamic IF and antenna filtering will be explored to enable efficient spectrum coexistence schemes. The ultimate goal of 6G-REFERENCE is to develop hardware enablers that could end up constituting a reference design for future 6G distributed radios.
Outcome
6G-REFERENCE will contribute to the European leadership in microelectronic solutions for communication and sensing infrastructure by developing hardware enablers for densified cell-free deployments, targeting not only coherent data transmissions but also high accuracy localisation and sensing, thus materialising the connection between physical, chemical, digital and human worlds.
The green transition in 6G-REFERENCE will rely on densified deployments of low-energy distributed nodes, capable of providing, at the same time, enhanced multiuser beamforming schemes for data transmission and accurate sensing. Enabling a densified deployment of distributed radio units, 6G-REFERENCE will contribute to improving the availability in high-density populated areas, ensuring coverage from multiple radio units in every corner.
Moreover, it will be achieved in a sustainable manner, from the energy efficiency point of view, including the use of the same integrated circuit hardware for sensing and communications. In addition, we will also directly contribute to SDG 13 on climate actions, by developing environmental chemical sensors in the antenna system hardware to potentially realise virtual environmental quality maps, also applied to secure clean hydrogen energy storage. 6G-REFERENCE will not directly address new business models but will indirectly enable their conception, especially by integrating communications with localisation and passive radar sensing, which may definitely boost the creation of new applications and businesses.
The ultimate goal of 6G-REFERENCE is to ensure the commercial feasibility of the developed hardware solutions not only by aligning them with current standardisation activities and goals, but also by ensuring that the standardisation work can be based on the correct knowledge of the capabilities and limitations of the developed hardware.
Consortium
- Centre Tecnologic de Telecomunicacions de Catalunya (CTTC).
- Ericsson AB (EAB).
- Universiteit Twente (UT).
- Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA).
- Anteral SL.
- MTU Australo Alpha Lab.
- Interuniversitair Micro-Electronica Centrum (IMEC).
- Eidgenoessische Technische Hochschule Zuerich (ETHZ).
- Advanced Circuit Pursuit AG (ACP).
- The University of Birmingham (UoB).
Disclaimer
This information is provided by the 6G-REFERENCE consortium under EC grant agreement 101139155 and does not necessarily reflect the views of the European Commission.
Please note, this article will also appear in the 23rd edition of our quarterly publication.
