Satellite Time and Location Option

Satellite Time and Location (STL) is a revolutionary new source for precision time based on the Iridium® constellation of satellites. With the reliance upon GPS and other GNSS signals becoming more and more common for critical applications, STL provides an ideal augmentation for these applications where "it just has to work." And with signal strengths approximately 1000x stronger, it can also provide high accuracy timing indoors where GPS and other GNSS signals can’t typically be reached.

The Challenge


GPS and other GNSS signals play a key role in the operation of critical infrastructure systems such as communications networks, financial systems, power grids, and more. Despite the fact GNSS systems do a good job of providing solutions for diverse applications, they were never designed to be used in many of the ways they are being applied today. And as critical applications push the envelope in their use of GNSS systems, the result is deficiencies which leave them vulnerable.

GNSS signals originate from 20,000 km above the earth and are very weak by the time the reach the ground. This means that they have difficulty working indoors and can be affected by interference ranging from benign sources like ionospheric conditions to more serious ones like intentional jamming. Commercial GNSS signals are also unencrypted, and therefore susceptible to spoofing which is a serious threat for critical applications.

The Solution

STL, delivered by Satelles, is a secure, robust timing solution that can be used to complement GPS and other GNSS satellite signals, making applications more resilient, reliable, and secure.

Originating from the Iridium® constellation of 66 low-earth-orbiting satellites, STL is 1,000 times stronger than GNSS systems, capable of reaching deep into buildings and overcoming jamming issues without the aid of local infrastructure. Cryptographic security features of STL also provide exceptional resilience to intentional spoofing.

Used in tandem with GPS and other GNSS signals, STL provides a powerful, resilient solution for critical timing applications. Spectracom precision timing products integrated with STL provide the perfect platform for GNSS augmented solutions as well as indoor solutions where GPS can’t be reached. If timing is critical to your application, contact Spectracom to learn more about STL and other Resilient Positioning, Navigation, and Timing solutions.

STL Benefits

Presentation: Adding Resilience and Trust to GPS

This presentation describes STL and its value for GPS-based timing systems. Its power signal also allows the possibility for synchronization of indoor timing systems without the need for a rooftop antenna system.

This content was first presented at several conferences starting in January 2017 including ATIS's Workshop on Time Sync in Financial Markets, "Time & Money" and ION's Precise Time, and Time Interval Systems and Applications (PTTI).