ARLINGTON, Va. — The U.S. Space Force is exploring strategies to bolster the resilience of the Global Positioning System (GPS) amid growing concerns about the constellation’s vulnerabilities. One option favored by Air Force Secretary Frank Kendall is to use smaller, lower-cost satellites to augment the existing GPS infrastructure. 

Known as Resilient GPS (R-GPS), these smaller satellites would provide the U.S. military additional sources of positioning, navigation and timing data. Kendall has identified R-GPS as a high priority that should move forward as soon as possible. However, the future of the program is uncertain as lawmakers are questioning its effectiveness and cost.

Speaking at a DefenseNews conference Sept. 4, Gen. Michael Guetlein, vice chief of space operations, said concept studies for R-GPS are ongoing but stressed that the program’s future hinges on congressional approval.

“We’re waiting on the 2025 budget on the Hill to see where it shakes out,” Guetlein remarked. 

The R-GPS program is being pursued under a rapid acquisition authority that Congress gave the Defense Department to kickstart high-priority projects without waiting for formal budget approvals. The Air Force is targeting fiscal year 2026 for more comprehensive funding.

Despite the military’s push for R-GPS, the House Appropriations’ defense subcommittee has raised concerns about whether simply adding more satellites would effectively counter jamming threats, suggesting that alternative PNT systems might be more effective. Additionally, the committee denied a $77 million funding request for R-GPS, questioning the program’s focus on space-based solutions without addressing vulnerabilities in ground equipment, such as the military’s lack of M-code GPS user equipment, which is more resistant to jamming.

A separate battle over future GPS funding

Over the past few months, the Space Force has been working to address House concerns, briefing appropriators and providing additional information ahead of House-Senate negotiations over the defense budget. The Senate has not opposed the R-GPS program.

Meanwhile, the Space Force’s Space Enterprise Consortium (SpEC) is reviewing industry proposals for R-GPS. The consortium released a request for prototypes and is expected to select five concepts for further study. One approach would be to provide regional coverage in areas where there’s high levels of jamming activity.

“What needs to be answered is ‘what can we do to shore up the civil signal and the military signal on GPS to get more resilience during times of crisis or conflict?'” Guetlein said. 

The debate over R-GPS also intersects with discussions about funding for the next-generation GPS IIIF satellites, manufactured by Lockheed Martin. While the Senate approved funding for two GPS IIIF satellites in the 2025 spending bill, the House only funded one. Sources indicate that the Department of the Air Force might slow down GPS IIIF purchases in 2026 to help finance R-GPS, given the surplus of four GPS III satellites already delivered and awaiting launch.

Lockheed Martin, which won the contract to produce up to 22 GPS IIIF satellites in 2018, has argued that steady orders are crucial to maintaining an efficient production line. The company also wants to make it clear that R-GPS should complement, not replace, the advanced capabilities provided by GPS IIIF. 

“Resilient-GPS is a great example of how military forces are quickly adapting to a changing competitive environment,” Jesse Morehouse, business development director for PNT at Lockheed Martin Space, said in a statement to SpaceNews

“While R-GPS’ smaller size can provide foundational PNT bandwidth and enable multi-launch capacity for agile and adaptive employment, GPS IIIF still remains necessary to provide the full suite of critical mission capabilities that government and civilian users depend upon,” Morehouse added. 

Guetlein said efforts to improve the resiliency of navigation satellites and other systems are part of a broader Department of the Air Force strategy aimed at “great power competition.” This approach reflects a significant shift in operational thinking, Guetlein noted, “This is not a bumper sticker; it’s about completely changing the way we think and the way we operate.”

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...