TOKYO (JAXA PR) — The Japan Aerospace Exploration Agency (JAXA, President: Hiroshi Yamakawa) and Sony Computer Science Laboratories, Inc. (Sony CSL, President and CEO: Hiroaki Kitano) have announced their plans to conduct in-orbit demonstrations of the long-distance laser communication system, which they have jointly developed with the aim of establishing a real-time, mass-data communication system for future inter-satellite communications and communications with ground stations.
The system, currently known as Small Optical Link for International Space Station (SOLISS), will be carried aboard the H-II Transfer Vehicle (HTV8) “KOUNOTORI-8”, the cargo transporter to the International Space Station (ISS), which is scheduled for launch on September 11th, 2019. The in-orbit demonstrations will be conducted using the Exposed Facility of the Japanese Experiment Module (JEM) “Kibo”.
Since 2016, JAXA and Sony have jointly conducted ground demonstrations of this long-distance laser communication technology which uses an optical disk technology for fine pointing, under the Request for Proposal (RFP) joint study framework of the JAXA Space Exploration Innovation Hub Center.*1
In the upcoming in-orbit long-distance laser communication demonstrations, the SOLISS system will be attached to the IVA-replaceable Small Exposed Experiment Platform (i-SEEP) hardware adapter installed on the JEM’s Exposed Facility to perform ground-to-low earth orbit (LEO) optical communication testing using a 1550 nm bandwidth laser.*2 JAXA and Sony plan to complete the demonstrations within fiscal year 2019.
As shown in figures 1 and 2 above, the SOLISS system has an optical communication unit, a biaxial gimbal, and a monitor camera that are partially exposed to space, while the rest is covered with a multi-layer heat insulator. The optical communication unit employs Sony’s optical disk technology, which is the fruit of Sony’s development starting in the 1970s and commercial applications such as CDs, MDs, DVDs, and Blu-ray discs.
The optical disk technology is high-precision, low power, compact, and mass production capable. The optical communication unit weighs approximately 1.2 kg, has a cross-sectional area of 90 mm x 100 mm, and is equipped with a built-in small optical control mechanism using optical disk technology. The unit is capable of bidirectional communication and can be operated in the same way as a terrestrial network, even in space, supporting an Ethernet protocol.
The monitor camera employs an omnidirectional camera to observe the operation of the biaxial gimbal. The photos taken can be sent to the ground not only via the ISS but also using SOLISS’s laser communication directly.
According to a statement by Vice President Koichi Wakata of JAXA, “The upcoming demonstration of long-distance laser communication technology will mark the first in-orbit demonstration for the Space Exploration Innovation Hub Center, and we have very high expectations for this technology. This technology, which employs a laser for in-orbit mass-data communication, will likely be widely used not only in the telecommunications industry, but in the future as a means of communication in the field of exploration. Specifically, it can be used as a means of communication between the Earth and the International Space Station, the Moon, and Mars.
“There is a wide range of potential applications, such as communication with the Moon rovers. I am confident that the utilization of the Japanese Experiment Module ‘Kibo’ will enable the timely demonstration of the SOLISS system in space. Going forward, the results of these demonstrations will contribute to the telecommunications industry on Earth and to the future exploration missions in space.”
President Kitano of Sony CSL remarked, “Long-distance laser communication technology enables transformation of our society with real-time broad-band communication around the globe as well as expanding the humanosphere and increased activity in space. Sony CSL is taking advantage of the in-orbit demonstrations to complete our long-distance laser communication system.
“It will be the first step for Sony to build upon the results of these demonstrations and put it into practical use in society as we commercialize it. The opportunity to use Kibo for the in-orbit demonstrations makes it possible to greatly advance the research and development of the optical communication system, much more quickly than if we had launched a small satellite for the same purpose on our own. The SOLISS system is built using consumer components. After the demonstrations, we will retrieve the SOLISS unit and perform follow-up analyses, which we expect will further accelerate our commercialization process.”
*1 Studies implemented based on the JAXA-Sony agreement concluded in 2016 for conducting fundamental and feasibility studies on long-distance communication system with tree-space laser link technologies as part of JAXA’s “Open Innovation Hub for Expanding Humanosphere and the Domain of Human Activity through Solar System Frontier Development,” a project commissioned by the Japan Science and Technology Agency (JST) under its innovation hub start-up support program.
*2 Communication tests with the ground are conducted with ground stations of Japan’s National Institute of Information and Communications Technology (NICT)