Japan Weighs Using Communications Satellites for Space-based Surveillance

The Yomiuri Shimbun

2:00 JST, December 25, 2023

The government is considering adding surveillance capabilities to the Self-Defense Forces’ next-generation communications satellites set to be launched in the 2030s.

To this end, the government is set to start developing a small-sized monitoring device to be installed in the satellites. The move is aimed at countering China and Russia, which have been developing “killer satellites” capable of destroying other countries’ satellites.

Communication satellites exchange highly confidential communications among SDF units and operate in geostationary orbit at an altitude of about 36,000 kilometers.

A massive amount of space debris exists due partly to tests by China and Russia aimed at destroying satellites, and it is increasingly important to strengthen space-based monitoring capabilities so as to avoid collisions or other potential problems.

The SDF plans to put three communication satellites into operation and will thus require at least three surveillance satellites.

In fiscal 2026, the government plans to launch Japan’s first “space domain awareness” (SDA) satellite, which specializes in surveillance activities. However, it remains unknown when the other two SDA satellites can be launched, as each costs about ¥100 billion to put into orbit. The government therefore aims to add monitoring capabilities to communications satellites to leverage them as alternatives to SDA satellites.

The SDF’s two extant communications satellites will end their service life between fiscal 2030 and fiscal 2031 and the government intends to equip their successors with monitoring sensors and other devices.

China and Russia both possess ground-based jammers that they use against other countries’ satellites. Consequently, Japan is considering equipping its new communications satellites with devices that can thwart such interference.

However, it will be necessary to downsize the monitoring devices to allow them to be installed on satellites, and with this goal in mind, the Defense Ministry has appropriated expenses of ¥200 million in the initial draft budget proposal for fiscal 2024.

The ministry plans to develop a small-sized monitoring device over three years from next fiscal year, carefully comparing costs related to SDA satellite launches and the installation of small monitoring devices in communications satellites.

Washington has early warning satellites that monitor North Korea’s missile launches and other activities that operate in the same orbit as communications satellites. The Japanese government plans to work closely with the United States in terms of boosting its surveillance system.

The Defense Buildup Program adopted by the government in December last year stipulated a plan to put multiple surveillance satellites into orbit with the aim of upping space-based vigilance.