Two military satellites communicated with each other using lasers

A pair of military satellites launched last year has successfully completed an experiment to demonstrate cross satellite communication using lasers in space. The company that developed the optical terminals said in a press release.  

Even as private players rush to set up constellations of their satellites in orbit, communication technology has mainly remained the same for over six decades. While communication speeds have improved considerably, a satellite still needs to send a message to a ground station on Earth to communicate with another satellite, even if it is orbiting just a few miles away. Reston, Virginia-based CACI International is working to change this and has now successfully demonstrated inter-satellite links.

Communicating with lasers

CACI deploys the CrossBeam free-space optical terminals on satellites to enable inter-satellite optical communication. The company claims that its technology can allow satellite cross-links as well as bi-directional satellite-to-earth links using systems that are less complex, smaller in size and weight, need less power, and therefore are cheaper to operate. 

Working in association with the Defense Advanced Research Projects Agency (DARPA) and Space Development Agency (SDA), CACI launched two satellites, named Able and Baker, equipped with these optical terminals in June last year, Gizmodo reported. 

The launch was also part of the Mandrake II program that is being conducted in association with the Air Force Research Laboratory's Space Vehicles Directorate (AFRL SV), the press release said. The Mandrake II program aims to evaluate the pointing, acquisition, and tracking algorithms that will be used in the optical terminals of these satellites.

On April 14 this year, the two satellites set to work their optical terminals over about 60 miles (100 km) and communicated for over 40 minutes. Infrared lasers were used to see over 200 gigabits of data first being encoded and then beamed to the receiver of the other satellite, which was received successfully. 

Defense applications of the technology

While laser communication is considered faster and more secure when compared to radio waves, you are unlikely to be served by optical satellite communication anytime soon. The technology is still being trialed for defense purposes and the Mandrake II program is also a part of the larger Blackjack project, being run by DARPA. 

Under the Blackjack project, a constellation of 20 satellites capable of optical communication will be launched into low-earth orbits and serve as a network mesh in space. This network will be government-owned and serve to connect the U.S. military to its bases, sensors and weapons across the world, Gizmodo said in its report. 

"Our national security depends on advanced, secure technology that enables modernized networks and enhanced intelligence systems for our warfighters using small satellites to operate at the speed of relevance," said John Mengucci, CEO and President of CACI. "In partnership with our mission customers, we are on the path to supporting the contested space domain with faster, more secure satellites."

Space News reported that the SDA plans to launch a tranch of 20 satellites this year and follow it up with 126 satellites by 2024. These satellites will be built by Lockheed Martin, Northrop Grumman, and York Space and feature optical communication between them, with ground stations and airborne platforms.