Imperial researchers awarded ARIA funding to transform the future of connectivity

Imperial academics will lead projects investigating the potential of High Altitude Platform Systems (HAPS) as part of future telecoms infrastructure.

Professor Kin Leung (Co-Director, School of Convergence Science) and Professor Rafael Palacios (Head of Department, Aeronautics) have been awarded a total of £1.9m from the Advanced Research + Invention Agency’s (ARIA) Enduring Atmospheric Platforms programme.

Professor Leung and Professor Palacios co-lead a research project for which they received £1.2m, with Professor Palacios and Professor George Papadakis being awarded £0.7m for StratoLink, a project being led by Voltitude.

The Enduring Atmospheric Platforms programme is backed by £70 million over 3.5 years. The programme will fund the development of technologies that enable aircraft known as High Altitude Platform Systems (HAPS) to operate reliably, cost-effectively and responsively, integrating into the existing telecoms system, and bolstering the UK’s sovereign capability.

HAPS can enhance connectivity in remote areas as well as serving regions where existing terrestrial and non-terrestrial communications infrastructures are insufficient to meet increased traffic demands or become damaged.

18 teams, known as R&D Creators, are being supported by ARIA to pursue research on HAPS.

Why HAPS?

Globally, billions are still without reliable connectivity. Over two billion don’t have access to the internet and are therefore locked out of an ecosystem offering economic and social benefits. For those with consistent connectivity, there is the underlying risk of damage to ground stations from natural disaster or conflict.

Traditional satellites orbit at 160-35,000 km above the Earth’s surface. Their signals decrease in strength and quality over such distances. A fleet of HAPS, which occupies the stratosphere at around 10-50 km above the surface, has the potential to serve as a new component of communications infrastructure particularly for communities currently lacking dependable connectivity or regions with inadequate network services.

Situated closer to us on Earth, HAPS could provide another layer of infrastructure with greater capability, more sovereignty and at lower costs than satellites. HAPS are also less detrimental to the environment as they can return to the surface for refuelling or recycling.

However, much work will be required before HAPS become part of our telecoms systems. We need to develop and verify enabling technologies prior to building a “full” and operational HAPS system. We need to determine how to power this infrastructure, keeping it in flight and functioning. The communications architectures that will use HAPS also need to mature, as well as pathways on deploying them in a commercially viable way.

Imperial’s HAPS research

Professor Leung and Professor Palacios’ research will design a fleet of AI-enabled HAPS. The fleet will comprise HAPS of different designs with different operational capabilities, testing and analysing their performance in the UK context, characterised by low sunlight, strong winds and high traffic demands.

Their investigation will explore the optimal positioning of HAPS, determining where HAPS should be in 3D airspace for the best possible service, as well as alternative power architectures that optimise energy consumption to sustain their functionality.

A unique aspect of Kin and Rafael’s work is their approach to optimising the fleet. Due to the challenging stratospheric environment, energy availability and regulatory constraints, modelling the system accurately will be difficult.

Kin and Rafael propose to develop novel distributed Reinforcement Learning (RL) algorithms. This means that each HAPS vehicle will be programmed to function autonomously, interacting and learning from its environment, collating data to enable the fleet to adapt its positioning, resource allocation and operational strategy accordingly. This AI-enabled approach aims to create distributed RL algorithms to deploy HAPS at scale while operating within regulatory requirements.

Professor Palacios and Professor Papadakis’ project will investigate stratospheric turbulence forecasting. One of the big unknowns is the wind environment at such altitudes which can have a very large adverse effect on the performance of slow-flying HAPS. Their project within the Enduring Atmospheric Platforms programme will seek enhancements in weather forecasting with local high-resolution simulations.

Convergence science

The Imperial teams undertaking this research have expertise in wireless communications, aircraft design, operational management, network AI and distributed computing. Kin and Rafael’s proposals put forward an integrated, cross-disciplinary, systems approach to designing the individual HAPS, HAPS fleet, algorithms and simulations, reflecting the vision of Imperial’s School of Convergence Science.

The School of Convergence Science is a mission-led initiative, building on Imperial’s world-leading research and interdisciplinary collaboration to solve significant societal challenges. HAPS is relevant to two of the missions developed by the Space, Security and Telecoms theme. The first, Thunderbird, an Autonomous Disaster Response programme which aims to achieve rapid deployment of communications infrastructure to regions affected by natural disaster and armed conflict. The second is LACE, Low-Altitude Advanced Communications and Earth Observation, a multi-layered membrane of interacting airborne vehicle and satellite infrastructure. HAPS represents an important component to both the Thunderbird and LACE concepts, and ARIA’s funding marks a step in progress for these ambitious ideas.

Professor Kin Leung, Space, Security and Telecoms Co-Director and Tanaka Chair in Internet Technology, Department of Electrical and Electronic Engineering and Department of Computing, says:

“We’re so pleased to receive this funding as it allows us to perform world-leading research across Imperial to develop and explore how HAPS could play a significant role in the future of telecommunications.

“At the School of Convergence Science, we’re championing the deep integration of disciplines to drive innovation, and this project is a wonderful example of convergence science in practice: colleagues with different areas of expertise and experience in different industries collaborating to solve a challenge that will shape how we connect in the future.”

Professor Rafael Palacios, Head of the Department of Aeronautics, says:

“I’m delighted that Imperial is to be one of the Enduring Atmospheric Platforms programme creators. We’re home to the UK’s leading Aeronautical Engineering department and we have exceptional researchers ready to help us address this challenge.

“Although we’ve witnessed significant leaps in progress in the telecoms sector over the past few decades, we need to continuously concentrate our efforts to improving our capabilities and resilience for the generations ahead. These projects reinforce Imperial’s deep commitment to research and innovation for the good of humanity.”