ALBUQUERQUE, N.M. — Integration and testing activities for an experimental navigation satellite are ramping up at the Air Force Research Laboratory’s Space Vehicles Directorate as the U.S. Space Force prepares to launch its first major positioning, navigation and timing demonstration in nearly 50 years.
The lab is on track to launch in late 2023 the third Navigation Technology Satellite, or NTS-3, built by prime contractor L3Harris Technologies. The effort will showcase advanced capabilities that could improve future GPS satellites or inform a new program to augment today’s constellation. Those technologies include steerable beams to provide regional coverage, a reprogrammable payload that can receive upgrades on orbit and protections against signal jamming.
Speaking with reporters during a recent visit to the Space Vehicles Directorate at Kirtland Air Force Base in New Mexico, NTS-3 program manager Arlen Biersgreen said the effort is part of a legacy of experimental positioning, navigation and timing, or PNT, missions that have shaped key military and civilian space technology.
The last NTS satellite flew in 1977 and showcased capabilities that proved integral to the GPS program. Biersgreen said the goal is for NTS-3 to create a pathway for a more regular demonstration cadence.
“The whole team has a vision for this not to be the last NTS in the near future,” he said. “The reality is — because of the threats GPS is experiencing and because of the importance that it has to military and civilian operations all over the world — we’ve got to have a faster cycle to keep up with the threats as they develop.”
In preparation for the 2023 launch, Biersgreen and his team expect to finish integrating and testing the spacecraft’s hardware and software this fall in time to deliver the satellite by the end of the year. The program recently completed key tests of major hardware and software components, including antenna arrays and the command-and-control system for the satellite bus and payload.
For the program’s ground segment, which will operate NTS-3 once on orbit, the team is eyeing integrated testing this fall and has ordered the hardware for its eventual mission operations center. In the meantime, the program has set up a mock-mission operations center for training and to ensure the various interfaces and systems work together. Once the real mission operations center is completed later this year, Biersgreen said, the team will use it for a factory compatibility test that will demonstrate functionality between the ground system and the spacecraft.
The program is also developing NTS-3 ground receivers, which allow military users to tap into the satellite’s advanced PNT capabilities. To date, the team has built four receivers and plans to provide six for the NTS-3 experiment.
Biersgreen said the program office is also eyeing opportunities to validate NTS-3′s performance during exercises with the military services. For example, the team had a chance to validate the receivers’ performance during a March exercised called NAVFEST, which is held annually at White Sands Missile Range, New Mexico. And in August, NTS-3 will be a part of the Army’s yearly PNT Assessment Exercise, or PNTAX.
During PNTAX, program officials wants to observe how the system works in a real-world environment and identify any necessary changes. The exercise also provides a chance to measure the satellite’s anti-jam capability, giving the Air Force Research Lab a “more convincing example of the utility of the techniques that we’re demonstrating,” Biersgreen said.
Once on orbit, NTS-3 will spend its first year performing more than 100 experiments, which will test various technologies and techniques. When the formal demonstration phase is complete, the satellite will continue to provide data for about two years.
As the lab plans for the experiment, acquisition offices within the Space Force and the Air Force are preparing strategies to buy and field the new technology. The Space Force is in the midst of a force design study that could drive changes to its current PNT architecture, and the serivce closely watching NTS-3 to see how it might augment GPS satellites.
The Air Force Life Cycle Management Center is particularly interested in the user equipment segment of the program and is making plans to take advantage of the program’s software architecture.
“We’re working closely with our mission partners so that the data coming out of the experiment is relevant for transition across space, ground and user segments,” Biersgreen said.