Harwell-based firm to develop ground-to-air RF beaming technology for persistent high-altitude platforms.
Harwell-based wireless power specialist Space Solar has secured a $1.7 million (£1.3 million) research contract from the UK’s Advanced Research and Invention Agency (ARIA) to develop radio frequency (RF) power-beaming systems for high-altitude aircraft.
The grant forms part of ARIA’s $93 million (£70 million), 3.5-year Enduring Atmospheric Platforms programme. Led by Programme Director Rico Chandra, the initiative supports the development of High-Altitude Pseudo-Satellites (HAPS)—unmanned stratospheric aircraft such as the Airbus Zephyr—designed to deliver alternative communications infrastructure to coverage blackspots.
Under the initiative, designated Project HAWK, Space Solar aims to decouple HAPS aircraft from on-board power generation. The concept uses a ground-based transmitter operating at 5.8 GHz to beam energy directly to a lightweight receiving antenna (rectenna) built into the aircraft’s wing, enabling continuous operation regardless of weather, season, or time of day.
The project targets delivering a net 300 watts of continuous DC power to a 20 kg payload at stratospheric altitudes for at least one week. The programme aims to reduce operational costs to under $660 per hour initially, with a long-term goal of bringing costs below $130 per hour.
Martin Soltau, Co-CEO of Space Solar, noted that energy availability remains a primary constraint for HAPS platforms, adding that the ARIA funding will accelerate the transition of its rectenna technology from laboratory testing to an integrated flight demonstration.
Space Solar will deliver the project alongside BAE Systems subsidiary Prismatic—developer of the PHASA-35 solar-powered platform—and MuWave Limited, which is designing the ground transmitter. The development builds on Space Solar’s HARRIER prototype, a retrodirective phased array capable of 360-degree beam steering, which was previously validated at Queen’s University Belfast.


















