Military Embedded Systems

DARPA wants satellite constellations to talk to each other


September 14, 2021

Lisa Daigle

Assistant Managing Editor

Military Embedded Systems

DARPA wants satellite constellations to talk to each other

ARLINGTON, Va. The Defense Advanced Research Projects Agency (DARPA) has announced a new push to create a novel optical communications terminal to interconnect diverse constellations of small low-Earth orbit (LEO) satellites into a resilient space layer, or what DARPA officials are calling an "internet of small satellites." 

The aim of the Space-Based Adaptive Communications Node (Space-BACN) is to create a low-cost, reconfigurable optical communications terminal that adapts to most optical intersatellite link (OISL) standards and enable seamless communication between various constellations that currently cannot talk to each other. 

“There could be tens of thousands of small satellites launched into LEO over the next decade as the demand around the world for affordable space-based capabilities grows,” said Greg Kuperman, Space-BACN program manager in DARPA’s Strategic Technology Office. “The problem with this growth is that optical communications links are currently engineered to only connect satellites within a given constellation – they can’t dynamically adapt waveforms to communicate with satellites in other constellations. This lack of OISL standardization results in a fragmented, stovepiped ‘Wild West’ space domain with new constellations that can’t interoperate, government satellites that can’t communicate between one another, and government satellites unable to take advantage of emerging commercial communications capabilities.”

To achieve its goal of satellites that could be reconfigured on-orbit to talk across different standards, Space-BACN will focus on three key technical areas: a low-cost, optical aperture capable of coupling into single mode fiber; a reconfigurable modem that can support multiple optical waveforms up to 100 Gbps; and a cross-constellation command and control approach to automate interactions between government and commercial satellites. 

A “one-stop” Space-BACN webpage hosting links to the special notice, solicitation, videos, FAQs, and other resources can be found at

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