The Navigation Technology Satellite-3 (NTS-3), an experiment funded by the Air Force Research Laboratory, will transmit PNT signals from geostationary orbit to complement GPS satellites in medium Earth orbit
COLORADO SPRINGS – The Navigation Technology Satellite-3 (NTS-3), an experiment funded by the Air Force Research Laboratory, will fly into geostationary Earth orbit in 2023 and will be used to augment the positioning, navigation and timing (PNT) services currently provided by GPS -Satellites provided.
The concept of adding another PNT layer could be significant given the Pentagon’s concern that signals from GPS satellites in medium Earth orbit (MEO) could be jammed or jammed during a conflict.
“We wanted to look at how to use a constellation that is truly a hybrid architecture,” Joanna Hinks, associate program manager for NTS-3 at AFRL, told reporters April 7 at the Space Symposium.
When NTS-3 was first conceived, “we looked at MEO first,” she said. However, it was later decided that GEO would be a better location for NTS-3 to allow researchers to evaluate the potential benefits of a multi-orbit PNT architecture.
“The idea here is that we already understand very well how navigation works from MEO,” Hinks said.
Another goal of NTS-3 is to test software-defined radio technologies so signals can be reprogrammed to confuse and defeat jammers. One from Parsons Corp. The ground system developed would integrate GPS and NTS-3 signals and evaluate the network’s performance in a noisy environment.
“Reprogrammable signals are a key area of focus,” Hinks said. This will require a flexible floor system and user receivers “that can handle reprogramming”.
The 1,250-kilogram satellite will be assembled at an L3Harris facility in Palm Bay, Florida. The company received an $84 million contract from AFRL in 2018 to build NTS-3. L3Harris integrates a digital mission data unit into a Northrop Grumman ESPAStar bus.
The satellite is scheduled to launch on the USSF-106 mission planned by the US Space Force. This would be the first national security mission to fly on United Launch Alliance’s new Vulcan Centaur rocket.
Once in orbit, NTS-3 would offer PNT service only over the United States “due to ease of access and the ability to easily install receivers in interesting locations,” Hinks said.
Because NTS-3 will be in geostationary orbit, “it’s constantly within sight of a site,” she said. In comparison, GPS satellites in six orbital planes orbit the earth twice a day and transmit PNT signals.
With a GEO satellite, “you don’t have to worry that you only have one or two satellites and they’ll be gone in a couple of hours and you won’t be able to see them,” Hinks said. “That’s one of the big things, but we’re just beginning to lay the groundwork for how you could have a constellation that’s not just in one orbit regime. That’s a big part of the experiment.”