A satellite phased-array transceiver that folds up for launch and unfolds in space has been shown to work successfully in orbit, as reported by researchers from Science Tokyo. By using an innovative approach to correct non-planar deformations in the deployable membrane antenna, this work lays the foundation for satellite constellation-based wireless communications in the Beyond 5G and 6G era.
As demand grows for high-speed internet access around the world, small satellites are set to play an increasingly important role in wireless communications. Compared with large communications satellites, small satellites are less expensive to build and launch, making it possible to deploy them in ‘constellations’ that work together to provide broad coverage. However, since these spacecraft are very constrained in terms of weight and volume at launch, they cannot accommodate conventional radio systems. Overcoming this limitation calls for new kinds of satellite communication technology.
One promising solution is the use of foldable membrane antennas inspired by origami. These thin, lightweight structures can be folded compactly for launch and unfolded into large-area antennas in orbit. The problem is that foldable membranes do not deploy into a perfectly flat plane. Small warps and bends modify the relative positions of radiating elements, interfering with the delicate synchronization of the phased-array transceiver system and degrading its performance.
Addressing this challenge, a research team led by Professor Hiraku Sakamoto from the Department of Mechanical Engineering, School of Engineering; Associate Professor Atsushi Shirane from the Laboratory for Future Interdisciplinary Research of Science and Technology, Institute of Integrated Research; and Professor Kenichi Okada from the Department of Electrical and Electronic Engineering, School of Engineering, all from Institute of Science Tokyo (Science Tokyo), Japan, conducted the world’s first in-orbit demonstration of a deployable phased-array transmitter that can correct for non-planar deformation. Their results were presented at the IEEE International Microwave Symposium (IMS) in Boston, USA, on June 10, 2026 and published online on 29 July,2026.
The team’s transmitter was mounted across two boards on a deployable membrane and carried aboard the RAISE-4 small satellite, which was launched on December 14, 2025, as part of the HELIOS-R project in JAXA’s Innovative Satellite Technology Demonstration-4. After the membrane unfolded in orbit, the system used a calibration method previously validated in ground tests to estimate the actual bend between its two boards. This enabled the system to electronically adjust the signal timing of each antenna element accordingly.
In-orbit experiments beginning on March 13, 2026, confirmed that directional beam control worked correctly both independently and simultaneously across the two transmitter boards, with calibration successfully compensating for the membrane’s non-planar shape after deployment. The team also investigated the effects of transmitter temperature on communication performance, offering valuable data for designing systems that can handle temperature variations in space.
By showing that a high-performance phased-array transceiver can be reliably packed into small satellites, this demonstration lays the groundwork for scaling up to larger deployable arrays. This brings next-generation satellite-based networks a step closer to reality, paving the way for better connectivity in underserved regions. “We expect our results to accelerate the adoption of satellite constellation-based wireless communication systems in the 6G era, helping realize a society in which anyone can connect anytime and anywhere,” says Sakamoto.
The lead researchers also emphasize that this work served as an important educational experience for younger researchers. “More than 20 students from Science Tokyo participated in the development of the space-demonstration system. The project therefore contributes not only to technological advancement but also to the education and training of future professionals in the increasingly important fields of space technology and wireless communications,” concludes Sakamoto.
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About Institute of Science Tokyo (Science Tokyo)
Institute of Science Tokyo (Science Tokyo) was established on October 1, 2024, following the merger between Tokyo Medical and Dental University (TMDU) and Tokyo Institute of Technology (Tokyo Tech), with the mission of “Advancing science and human wellbeing to create value for and with society.”
Reference
Title: On-Orbit Demonstration of a Deployable Ka-Band 16-Element Active Phased-Array Transmitter
Journal: IEEE International MTT Symposia (IMS)
DOI: 10.1109/IMSRFSA70221.2026.11624288
10.1109/IMSRFSA70221.2026.11624288
Experimental study
Not applicable
On-Orbit Demonstration of a Deployable Ka-Band 16-Element Active Phased-Array Transmitter
29-Jul-2026