Tiny satellites face big data limits: How foldable antennas could change CubeSat missions

An origami-inspired reflectarray antenna developed by researchers at Institute of Science Tokyo enables CubeSats to achieve high antenna gain while fitting within the tight size constraints of small satellites. Weighing just 64 grams, it folds compactly inside a 3U CubeSat for launch and expands in space. Such designs could support higher data-rate communications, expanding the capabilities of future CubeSat missions, including deep-space and lunar exploration.

The growing use of small satellites is opening new possibilities for advanced space applications. These include CubeSats, a class of standardized small, cubical satellites. CubeSats are widely used for low-cost research missions and for testing space technologies that would otherwise be too expensive or risky to demonstrate on larger satellites.

These missions require reliable communication systems. However, the small size of CubeSats makes it difficult to install conventional high-gain antennas, which are typically too large and heavy. To overcome this limitation, engineers are developing foldable antennas that can be compactly stowed inside the satellite during launch and then deployed once the spacecraft reaches orbit.

Now, researchers from Institute of Science Tokyo (Science Tokyo), Japan, have developed a 5.8 GHz origami-inspired deployable reflectarray antenna designed to provide high antenna gain while remaining compact enough for small satellites. The antenna is intended for OrigamiSat-2, a 3U CubeSat measuring 10 cm × 10 cm × 34 cm, which is being developed by the same university and is scheduled for launch in 2026. The system aims to improve the communication capabilities of small satellites used in applications such as space-based internet services and disaster monitoring.

The project was led by Associate Professor Takashi Tomura, together with graduate students Kodai Suzuki and Haruki Kurokawa (at the time of the research) from the Department of Electrical and Electronic Engineering, Science Tokyo, and Professor Hiraku Sakamoto from the Department of Mechanical Engineering, Science Tokyo. The study is published in the journal IEEE Transactions on Antennas and Propagation.

“Our origami-inspired antenna can be compactly stowed and reliably deployed—critical for pre-launch qualification of CubeSat hardware,” says Tomura.

The antenna consists of a primary radiator that generates the radio signal and a reflectarray that directs and strengthens the signal. The reflectarray is made from a flexible two-layer membrane composed of conductive and dielectric technical textiles. Within this membrane, flexible printed circuit substrates shaped into small U-like structures are sewn into place to form the reflectarray elements that control how radio waves are reflected.

To fit the antenna inside a small satellite, the composite membrane is folded using a flasher origami pattern. The entire system can be compactly stored within a volume of just 10 cm x 10 cm x 6 cm and weighs only 64 grams, including the deployment mechanism.

In orbit, the antenna is deployed using lightweight shape-memory booms that operate much like a pop-up mechanism and expand to about 2.6 times its stowed footprint, achieving a storage ratio of 265%.

The communication system uses a beam-tilting primary radiator together with a reflectarray. The beam-tilting radiator helps reduce signal loss caused by structural blocking, while the reflectarray elements convert incoming linearly-polarized waves into circularly-polarized waves suitable for satellite communication.

The researchers evaluated the antenna through measurements performed in an anechoic chamber, a specialized facility that absorbs reflections to simulate free-space conditions. In these tests, the antenna achieved a circularly polarized gain of 18.0 dBic, while the reflectarray element produced a circularly-polarized reflection phase of 280 degrees.

“Our results show that even ultra-small spacecraft can carry large-aperture, high-performance antennas, greatly enhancing their communication capabilities,” says Tomura.

With more CubeSat missions planned for the future, including missions requiring communication to as far as the moon, such deployable antenna designs could play an important role in space exploration.