Japan Backs Development Of Flexible, Secure Digital Satellite Payload
Subsidy Aims To Boost Competitiveness Of Future Communications Spacecraft
Mitsubishi Electric has received a government-backed subsidy to develop a full digital communications payload designed to make future geostationary satellites more flexible in orbit and harder to jam or intercept.
“Our goal is to help realize internationally competitive satellite services and systems and ensure the autonomy of Japan’s satellite systems.”
Akira Funakoshi, Mitsubishi Electric
The award comes under the second phase of the Japan Aerospace Exploration Agency’s Space Strategy Fund, which finances development and demonstration of internationally competitive communications payload technologies by private companies and universities. The project positions Mitsubishi Electric as the representative organization for a multi-year effort to advance digital payload architectures for the 2030s.
Under the program, the company plans to build a full digital payload that can change its communications functions after launch through software updates, rather than relying solely on fixed hardware. The design calls for a digital payload processor that will perform signal processing and enable in-orbit reconfiguration of communications control functions, allowing operators to adjust coverage patterns and capacity as demand shifts by region and time of day.
A central element of the concept is the use of a direct radiating array antenna that can see virtually the entire Earth-facing hemisphere from geostationary orbit. By controlling the excitation of thousands of individual antenna elements with digital beam forming, the payload is expected to steer radio beams in arbitrary directions and reshape coverage footprints without mechanical movement.
Mitsubishi Electric also intends to embed advanced security features into the payload, including functions to conceal communications content and protect signals from jamming and detection by third parties. Those capabilities will rely on high-performance application-specific integrated circuits to handle the required processing volume while keeping the payload small and low-power enough to be flown on commercial geostationary satellites.
The company is drawing on experience from its work on JAXA’s Engineering Test Satellite-9, which helped build the digital signal processing know-how underpinning the new payload architecture. “We are very pleased to have been selected as the representative organization for the Space Strategy Fund project and to have received the grant. Based on the knowledge and technological capabilities we have cultivated through our satellite development to date, we expect to develop a full digital payload that uses digital signal processing technology to flexibly adjust its functions in orbit after launch,” said Akira Funakoshi, senior manager of the Satellite Full Digital Payload Engineering Section at Mitsubishi Electric’s Kamakura Works. “Our goal is to help realize internationally competitive satellite services and systems and ensure the autonomy of Japan’s satellite systems.”
Tokyo-based satellite operator SKY Perfect JSAT Corporation will participate as a collaborating organization, assessing potential use cases and performance requirements for communications satellites in the 2030s. Insights from the operator’s market analysis are slated to feed directly into payload design, with the goal of aligning the new hardware and software with future commercial demand.
Mitsubishi Electric said the broader objective is to support “internationally competitive satellite services and systems” and to strengthen the autonomy of Japan’s satellite infrastructure at a time when most digital payloads are still developed and manufactured in Europe and the United States. The company expects the combination of flexible beam steering, software-defined control, and built-in security to position Japanese-built geostationary communications spacecraft more competitively in global markets.