The U.S. Space Force is actively exploring new technology integrations for its next-generation GPS satellites. However, persistent delays in a crucial demonstration program could hinder these efforts.

Originally, the Space Force planned to launch the Navigation Technology Satellite-3 (NTS-3) demonstration in 2022. The aim was to experiment with innovative positioning, navigation, and timing signals and payloads to inform the design of future GPS satellites. Development has been led by the Air Force Research Lab alongside L3Harris, and while progress on the satellite itself has been timely, issues with the launch vehicle, specifically United Launch Alliance’s Vulcan Centaur, have caused significant setbacks. Currently, the Vulcan rocket awaits final certification from the Space Force, which has stalled the program.

Cordell DeLaPena, responsible for the Space Systems Center’s positioning, navigation, timing, and satellite communications portfolios, stated that the prolonged timeline for launching NTS-3 will limit opportunities to incorporate its technology into upcoming GPS production lines. He emphasized that delays in experimentation impede the data collection needed to assess the technology effectively.

The Space Force intended for NTS-3 capabilities to enhance its latest GPS satellite variant, known as GPS IIIF. The service has plans to purchase 20 of these satellites from Lockheed Martin, having already ordered 10, with the first five expected to be delivered starting in 2027. DeLaPena mentioned that while the GPS IIIF is nearing the conclusion of its design phase and is transitioning toward production, there remains potential for adjustments. If the NTS-3 technology proves successful in upcoming launches, it might still be possible to incorporate it into the remaining satellites.

Should the Space Force miss the opportunity to embed NTS-3 technology in the first five GPS IIIF satellites, there may be chances to add such technology in subsequent batches or integrate it into efforts like the Resilient GPS (R-GPS) program. R-GPS aims to augment the GPS constellation with smaller, lower-cost satellites.

The NTS-3 demonstration and the R-GPS initiative are part of a comprehensive strategy to rethink navigation and timing capabilities. Traditionally, the military’s GPS satellites have been launched into medium Earth orbit, similar to the intended operation of R-GPS. However, the Space Force is contemplating a multi-orbit approach, which would place NTS-3 in geosynchronous orbit while low Earth orbit PNT satellites are also considered in collaboration with the Space Development Agency’s Proliferated Warfighter Space Architecture.

DeLaPena pointed out that demonstrating a hybrid navigation capability across multiple orbits is a key objective for the NTS-3 program, noting that other countries such as Japan, South Korea, and India are investigating geosynchronous-based systems. In addition, the Space Force is conducting an analysis of alternatives to outline a strategic roadmap for future PNT capabilities, with findings expected to culminate in summer 2023.