Viavi Solutions has announced milestones in 6G and artificial intelligence (AI) research based on company’s 6G Forward Program. As 6G is the first AI-native generation of wireless communications, data sources such as a 6G city-scale digital twin will be vital for training other elements of network such as 6G AI-native air interface (AI-AI).

In 2022, VIAVI announced support for research at Institute for Wireless Internet of Things (WIoTs) and Open6G cooperative research centre at Northeastern University, as part of VIAVI 6G Forward Program. A key aspect of research was large-scale radio frequency (RF) propagation channel modeling based on AI and machine learning (ML) technologies to develop a city-scale digital twin of a 6G network.

The digital twin research has expanded and includes:

  • Use of AI/ML to augment ray tracing for RF propagation modeling to drive the digital twin.
  • Conducting real-world measurement campaigns in Northeastern Boston campus using VIAVI ranger rugged RF capture and playback instrument.
  • Incorporating higher-layer key performance indicators (KPIs) in digital twin, to more effectively model effects of network conditions on application performance.

Commenting on the announcement, Dr Ian Wong, chief technology officer (CTO), VIAVI Solutions, said, “Our research collaboration with Northeastern University has led to breakthroughs in the use of AI/ML for radio propagation modeling. We believe this research is critical in enabling large-scale network digital twins, which VIAVI is well poised to deliver given our leading network emulation solutions in lab and network monitoring and optimisation solutions in field, gathering data from actual operator networks.”

Meanwhile, Professor Tommaso Melodia, director, WIoT,Northeastern University, said, “At Northeastern’s Institute for WIoT, we have been using VIAVI’s state-of-the-art testing and measurement equipment to model and deploy high-fidelity digital twins of real-world wireless networks on our open radio access network (RAN) digital twinning platform, Colosseum. This will facilitate research, development, and experimentation of AI-driven solutions for 5G and beyond networks in a risk-free digital-twinned world with hardware in the loop.”     
AI-AI has appeared as a shift in conventional methods of developing, standardising, and commercialising communication technologies with goal of effectively supplying data to applications while addressing communication problems and hardware limitations. In physical layer of wireless communications, the neural receiver concept suggests replacing traditional signal processing blocks with trained AI models.

To enable comprehensive testing of neural receivers, VIAVI has developed and demonstrated its own receiver as part of an end-to-end test and training environment. The base station employs an AI-aided constellation design, where modulation block is replaced with a neural network to design custom constellation for receiver. The VIAVI in-house developed neural receiver is generalisable over various channel models and modulations, delay and doppler, signal-to-noise ratio (SNR) and other conditions, which is vital for deployment in practical systems. VIAVI used open-source and in-house libraries to implement transceiver architecture.

Further, Dr Stephen Wang, managing director, VIAVI Marconi Labs, said, “VIAVI continues to explore and develop groundbreaking future generations of wireless technology, and we are at frontier of AI-native 6G. From neural receivers to rate-splitting multiple access for semantic networks, our 6G research helps industry create networks that dynamically adapt to different environments and conditions. We look forward to working with research labs and network equipment manufacturers to accelerate development of these technologies.”