Duration: 18 months
The concept of transmitting power over free-space using RF beaming is gaining momentum, with different initiatives for space and ground applications around the world, including the SOLARIS initiative. A key to the success of such applications is the DC to RF conversion efficiency. This project aims to:
- tailor existing amplifiers to the needs of the power beaming system and see how far existing technologies can be pushed in terms of efficiency and
- investigate the use of GaN15 technology to design a transistor specifically tuned to the very narrow frequency band (almost single tune) centred at a frequency in the 5-10 GHz range, initially 5.8 GHz. The system could be tuned to higher frequencies if the efficiency does not deteriorate significantly. A higher operating frequency would allow to reduce the size of the antennas used for the power beaming.
The very narrow operating band can be exploited to maximise the conversion efficiency of the device. Initial studies indicate that transistor power added efficiencies (PAEs) on the level of 85-90% could be achieved. This constitutes a significant improvement compared to existing off-the-shelf components which can achieve power added efficiencies on the level of 55% maximum. This would constitute one of the major stepping stones towards the construction of an efficient power beaming system and for future energy networks.
In our development, we are targeting RF power levels of 2-3 W for the device. The novelty resides in the design of highly efficient transistors using GaN technology exploiting narrowband requirements of power beaming systems. This activity would allow the European Space Agency to directly contribute to the technological developments in power beaming at AIRBUS and would also directly support Zeus, the long-distance ground-to-air power beaming demonstration planned for summer 2025 at AIRBUS facilities in Germany.