Inter-Satellite Terminal

The Inter-Satellite Terminal (IST) is a space-qualified hardware solution developed by Singapore's Addvalue Technologies to facilitate continuous communications for Low Earth Orbit (LEO) satellites. Traditionally, small satellites can only transmit data when passing over a ground station, leading to significant latency. This terminal bypasses that constraint by connecting directly to the Inmarsat ELERA L-band geostationary constellation, providing a persistent data link regardless of the satellite's position relative to Earth. Commercial uptake is primarily driven by operators of Earth observation and sensing constellations who require immediate tasking and telemetry. The system is marketed as part of the Inter-Satellite Data Relay System (IDRS). Known adopters include Capella Space for their synthetic aperture radar satellites and various research institutions looking to eliminate the 'blackout' periods inherent in traditional ground-segment architectures. The terminal is typically sold as a hardware-plus-service package in partnership with satellite network providers. The Garage desk notes that while this technology solves the latency issue, it introduces dependency on a third-party geostationary network. Buyers should verify the specific licensing requirements for L-band transmissions in their target jurisdictions and the impact of the terminal's power consumption on the host satellite's thermal budget. We would also seek to confirm the current throughput limits, as L-band relays offer high reliability but generally lower bandwidth compared to direct X-band or optical downlinks.