IN Brief:
- Keysight and IEMN have demonstrated a dual-polarised non-line-of-sight sub-THz communication link using RIS technology.
- The testbed used Keysight signal generation and analysis equipment with VDI converters and a Micro Harmonics orthomode transducer.
- The work addresses signal blockage, path loss, and capacity limits in future indoor 6G environments.
Keysight Technologies and the Institut d’Électronique, de Microélectronique et de Nanotechnologie have demonstrated a dual-polarisation, non-line-of-sight sub-terahertz communication link using reflective intelligent surface technology.
The work was carried out with IEMN, Virginia Diodes, and Micro Harmonics, and uses reflective intelligent surface, or RIS, techniques to redirect sub-THz signals in obstructed indoor environments. The project also uses dual-polarisation transmission to increase channel capacity without requiring additional spectrum.
Sub-THz frequencies are being explored as a key enabler for future 6G systems because they can support very high data rates for indoor applications such as smart factories, advanced laboratories, high-density research environments, and immersive communications. The same frequencies also face severe propagation challenges. Signal blockage, high path loss, alignment sensitivity, and non-line-of-sight operation remain major obstacles before the technology can move from research into practical system design.
The demonstration combined Keysight’s arbitrary waveform generator, VXG signal generator, and UXR oscilloscope with VDI frequency converters and a Micro Harmonics orthomode transducer. Using Keysight PathWave Signal Generation and Vector Signal Analysis software, the team generated and analysed waveforms based on the IEEE 802.15.3d physical-layer frame structure.
That setup allowed over-the-air evaluation of modulation performance across each RIS polarisation channel in a dual-polarised sub-THz non-line-of-sight transmission scenario. The work was carried out within the European TIMES project and France 2030 PEPR Future Networks SYSTERA activity, and is expected to feature in the technical programme at European Microwave Week in London in October 2026.
Advanced connectivity is becoming part of the same industrial design conversation as edge compute and physical AI. Rutronik’s Intel processor support for robotics and automation placed local inference, multi-sensor processing, and real-time control inside the industrial platform stack. Future factories will need higher-capacity links for sensing, robotics, digital twins, machine vision, and distributed compute, with radio reliability becoming part of production infrastructure.
RIS technology offers one possible route through the indoor propagation problem. Rather than relying only on direct paths between transmitter and receiver, a reflective surface can shape propagation by redirecting energy toward a desired location. In sub-THz systems, where blockage can break a link, engineered reflection could help maintain connectivity around corners, equipment, walls, or moving obstructions.
Dual polarisation adds another dimension by carrying separate channels through orthogonal polarisations. That can improve spectral efficiency and capacity, while also creating additional measurement and modelling requirements. Polarisation-dependent propagation, channel behaviour, alignment, surface response, and interference all have to be characterised before system designers can treat the technique as dependable.
Test and measurement capability is therefore central to 6G research. At sub-THz frequencies, small errors in frequency conversion, signal generation, analysis, antenna alignment, or calibration can distort conclusions. Engineers need repeatable testbeds that can evaluate modulation, waveform structure, channel response, and surface behaviour under realistic conditions.
6G standardisation will not be built on a single technology. It will draw from advances in spectrum use, antennas, channel modelling, AI-assisted radio control, sensing, edge compute, security, and semiconductor devices. RIS-assisted sub-THz links sit within that larger research stack, with value depending on whether they can offer coverage and resilience without adding unacceptable complexity, cost, or installation constraints.
The Keysight and IEMN demonstration moves one of those questions from theory toward measured performance. Indoor 6G, especially in industrial and research environments, will depend on high-capacity links that can survive obstructed paths, moving equipment, and dense wireless conditions.
