NASA's Optical Comms Demo Achieves Data Transmission Over 140 Million Miles

NASA's Optical Comms Demo Achieves Data Transmission Over 140 Million Miles
by Clarence Oxford
Los Angeles CA (SPX) Apr 26, 2024
NASA's Deep Space Optical Communications (DSOC) technology aboard the Psyche spacecraft has successfully transmitted engineering data from beyond 140 million miles away, showcasing its capacity for future space communication. The technology, although not essential for Psyche's data transmission needs, interfaced effectively with the spacecraft's existing radio frequency transmitter.

The trial not only emphasizes the potential enhancements optical communications could bring to deep space data transmission but also underscores its viability for supporting future missions, including manned missions to Mars.

"We downlinked about 10 minutes of duplicated spacecraft data during a pass on April 8," said Meera Srinivasan, the project's operations lead at NASA's Jet Propulsion Laboratory in Southern California. "Until then, we'd been sending test and diagnostic data in our downlinks from Psyche. This represents a significant milestone for the project by showing how optical communications can interface with a spacecraft's radio frequency comms system."

The DSOC demonstration has been instrumental in proving the feasibility of transmitting data at speeds surpassing current deep space communication technologies by up to 100 times.

Since its launch on October 13, 2023, Psyche has maintained stability and health on its journey to the asteroid belt between Mars and Jupiter.

Exceeding Performance Goals
The DSOC's test performance peaked with a transmission of test data at 267 Mbps from its near-infrared downlink laser on December 11, 2023. This speed, similar to terrestrial broadband services, was achieved when the demo transmitted a 15-second ultra-high-definition video and other test data from 19 million miles away.

The spacecraft's capability to send and receive data has naturally diminished with increased distance, yet it still impressively managed a 25 Mbps transmission rate during the April 8 test, far exceeding the project's initial 1 Mbps target.

"After receiving the data from the DSN and Palomar, we verified the optically downlinked data at JPL," said Ken Andrews, project flight operations lead at JPL. "It was a small amount of data downlinked over a short time frame, but the fact we're doing this now has surpassed all of our expectations."

Exploration and Experiments with Optical Tech
The DSOC has conducted several notable tests since Psyche's launch, including the successful transmission and reception of data involving digital pet photographs and extensive engineering data to assess the system's performance.

"We've learned a great deal about how far we can push the system when we do have clear skies, although storms have interrupted operations at both Table Mountain and Palomar on occasion," noted Ryan Rogalin, the project's receiver electronics lead at JPL.

JPL also conducted a test involving the simultaneous use of multiple ground stations, demonstrating the potential for an "arrayed" approach to enhance signal reception from deep space.