Satelles

Satelles is a Reston, Virginia-based positioning, navigation, and timing (PNT) technology company founded in 2012 and acquired by Iridium Communications in 2023 — developer of the Satellite Time and Location (STL) service, a GPS-independent PNT system that delivers precise timing and coarse positioning signals using Iridium's LEO satellite constellation, offering resistance to jamming and spoofing that GPS cannot match.

Satelles STL operates by modulating a timing and location signal onto the existing Iridium L-band communications waveform broadcast from all 66 Iridium NEXT satellites in polar low Earth orbit at approximately 780 km altitude. Because Iridium satellites are approximately 30 times closer to Earth than GPS satellites (which orbit at 20,200 km), the Iridium signal arrives at Earth's surface with 30 dB (1,000x) more signal power than GPS L1 signals — making STL dramatically harder to jam (requires 1,000x more jamming power to overpower) and more penetrating indoors and in urban canyons where GPS signal is often blocked or degraded.

STL provides timing accuracy of approximately 200 nanoseconds — sufficient for critical infrastructure applications including 5G base station synchronization, financial market timestamp compliance, power grid synchronization, and telecommunications network timing where Coordinated Universal Time (UTC) traceability within sub-microsecond accuracy is mandated by industry standards and regulatory requirements. The positioning component (coarser, approximately 50-meter accuracy) is supplementary to the timing function, useful as a backup position reference when GPS is unavailable or being spoofed.

The anti-spoofing capability distinguishes STL from GPS: Iridium's proprietary signal modulation and encryption makes generating a false STL signal (the basis of GPS spoofing attacks that have disrupted maritime navigation and drone operations) technically infeasible without Iridium's encryption keys. GPS's open-signal architecture was not designed with spoofing resistance, and civilian GPS receivers cannot authenticate signal authenticity.

Following Iridium's acquisition of Satelles in 2023, STL is being integrated as a standard augmentation to Iridium's commercial services portfolio, potentially reaching Iridium's entire enterprise customer base. Critical infrastructure operators (utilities, financial institutions, government facilities) represent the primary target market for GPS backup timing services.