WASHINGTON — Sierra Space announced May 8 it has completed a ground-based demonstration of a navigation satellite prototype for the U.S. Space Force’s Resilient Global Positioning System (R-GPS) initiative, as the military continues to explore back-up options for its GPS constellation.
The demonstration, conducted in a laboratory using a “FlatSat” setup, tested Sierra Space’s satellite hardware and flight software, along with ground communications systems. FlatSat configurations allow engineers to simulate mission operations using real spacecraft components without full assembly, speeding up development cycles.
Sierra Space, based in Colorado, is one of three companies selected in 2024 to compete in the Space Force’s R-GPS program, which aims to supplement traditional GPS satellites with smaller, commercially developed systems. The other two contractors are Astranis and L3Harris.
Sierra Space’s proposed satellite includes a positioning, navigation and timing (PNT) payload developed with General Dynamics Mission Systems. The payload is designed to support both GPS and Europe’s Galileo signals, enhancing global coverage and signal resilience.
The R-GPS program is part of a broader Pentagon push to diversify and harden its satellite infrastructure amid growing concerns over the vulnerability of large, high-cost satellites to interference or attack. The Space Force plans to select at least one design for an on-orbit demonstration in the next phase of the program.
