The United States Department of Defense has selected SpaceX’s ride share program to launch two cubesats that will demonstrate optical communications between two satellites and between satellites and a military drone spacecraft. The satellites will maneuver to a sun-synchronous orbit after being launched on SpaceX’s Transporter-2 mission next month.
Cubesat manufacturer General Atomics Electromagnetic Systems has already completed ground tests of the 12U cubesats, which are equipped with the laser communications terminals that will be used for the tests. The mission is being organized by the Department of Defense’s Space Development Agency.
Functional optical, or laser, communications will be key to the mesh network of small communications satellites in low Earth orbit that the Space Development Agency plans to launch in the near future. The satellite constellation is officially referred to as the Transport Layer, a reference to a seven-layer computer networking model.
The networking transport layer contains important protocols for managing data traveling over the network, including ones that manage flow control to ensure that the receiving device is not overwhelmed by large amounts of incoming data. The Space Development Agency simply co-opted the name for a constellation that will theoretically be able to handle large amounts of data traveling between command centers and remote assets.
General Atomics president Scott Forney called the planned experiment in optics-based communications “one of the first steps to validate the use of optical communications to provide low latency, secure data directly to weapons and warfighters.”
The Department of Defense is not pretending it will be easy. The technology still needs to be proven out and especially needs to be interoperable across multiple manufacturers of the satellites involved. Common standards across manufacturers are what makes it possible for technologies like Wi-Fi and USB to function regardless of whether a device runs Android, iOS, Windows, or Linux.
However, this has not always stopped manufacturers from trying to effectively “reinvent the wheel” with their own standards. Such a thing could introduce an unnecessary complication in military applications like the Transport Layer constellation if a larger manufacturer tries to muscle in with its own ideas.
“We have to demonstrate that it is feasible to create a market of multiple vendors that have interoperable optical comm terminals that can fulfill the needs of a proliferated LEO architecture. … We’re choosing to focus our efforts on a single protocol, and to set up the manufacturing side for success by not over complicating the system,” said Space Development Agency optical communications lead Mike Butterfield.
The Space Development Agency has previously tapped SpaceX to build and launch four OPIR-equipped satellites that can assist with tracking incoming missiles. SpaceX has also demonstrated its ability to save taxpayer dollars well enough to impress the new U.S. Space Force, which saved $52.7 million over the course of two launches by approving the use of previously flown boosters to launch some GPS satellites last September.
This is certainly a far cry from the days when SpaceX issued a legal challenge to competing launch service provider United Launch Alliance and the U.S. military for more equal footing in competing for launch contracts. The United Launch Alliance certainly put up a fight about it at the time, but now has to deal with the fact that SpaceX can compete on costs by providing “ride share” services for small satellites like the ones being used for the Department of Defense’s optical communications experiment, as well as making use of previously flown boosters, some of which have flown as many as ten times.