A land of ice and snow, Antarctica’s situation at the extreme south of Earth makes the continent a perfect location for satellites that weave polar paths around the planet to communicate with the ground.
But the extreme weather also limits flight travel windows to and from the continent and yields brutal field conditions, creating significant barriers for humans to build and maintain Antarctic communications systems.
NASA’s McMurdo Tracking and Data Relay Satellite Relay System (MTRS), located on Ross Island, Antarctica, is one conduit for spacecraft to connect with their users around the world. As more missions collect greater data volumes and have urgent delivery needs, like weather and disaster-tracking satellites, MTRS offers them essential communications links.
Upgrades to the system, completed in November 2017, strengthened the reliability of science data transport and will double data rates to 600 megabits per second (that’s like downloading 19 songs a second), transforming space communications for polar-orbiting missions.
MTRS complements the McMurdo Ground Station, an antenna station within NASA’s global Near Earth Network that receives data from missions passing overhead and delivers it to its destination over terrestrial communications pipes.
This may take some time, so when spacecraft such as the Soil Moisture Active Passive (SMAP) mission, which mapped flooding from Hurricane Harvey, have lots of data or need to deliver it quickly, MTRS beams the data up to NASA’s Tracking and Data Relay Satellite (TDRS), a communications satellite.
TDRS then sends the data down to NASA’s ground station at the White Sands Complex in Las Cruces, New Mexico, making it much faster to route time-sensitive data to its end destination.
“More and more missions today have high data volumes and pressing delivery requirements,” said Salem El-Nimri, project development lead for the MTRS upgrades. “And you can’t rely on the physically smaller data pipes on the ground alone for this.”
Aside from the higher data rate capability to transmit more data with fewer delays, the recent upgrades also added forward-error correction, which ensures data is delivered reliably in case of a communications issue.
But making the enhancements was challenging in the frigid Antarctic environment. The upgrade team spent months planning before their plane touched down on skis onto the Ross Ice Shelf, a few hundred-feet-thick ice mass next to Ross Island.
The six-member team began developing and testing hardware in May 2017 at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, which contains an exact replica of the MTRS development unit. The hardware was then tested with receivers at the White Sands Complex, which accept space data through MTRS.
Finally, the team worked an aggressive hardware installation and testing schedule through November to accommodate Antarctica’s flight window constraints and climate challenges. The enhanced MTRS was tested for performance with three TDRS spacecraft and the SMAP mission.
The forward-error correction upgrades are operational to serve MTRS users. The increased data rate capability from MTRS will be operational after further upgrades are made at the White Sands Complex, including hardware enhancements to antenna receivers and a small change to the MTRS hardware.
Links to related articles:
- NASA Space Communications Resources in Antarctica
- Antarctic Selfie’s Journey to Space Via Disruption-Tolerant Networking
- New System Giving SMAP Scientists the Speed They Need
By Seema Vithlani
NASA's Goddard Space Flight Center, Greenbelt, Md.