Intelligent GPS Repeater System
for Road & Rail Tunnels

Essential Ingenuity at Work

Resilient positioning, navigation and timing (RPNT) is the convergence of positioning, navigation and timing technology with non-traditional and emerging technology to improve the reliability, performance and safety of mission-critical applications in the air, on land and in the sea. RPNT solutions are used where even the smallest discrepancy in data accuracy, availability and stability can result in a mission failure, loss of life, or battlefield disadvantages, and significant economic loss.

Orolia is a world leader in resilient positioning, navigation and timing technology and a global manufacturer of precision time and frequency systems and GPS simulation systems.

These two technology areas are brought together to form our Resilient Intelligent GPS Repeater Systems for Tunnels.

Why do we need Intelligent GPS Repeater Systems in Tunnels?

GPS systems have become the ubiquitous technology for positioning and navigation today. Whether in portable devices and smartphone apps or in-built into vehicles, 'sat nav' is the technology we use to find our way and GPS tracking is the technology we use to monitor our progress.

GPS-based positioning within tunnels is highly desired for a number of reasons including:

Social changes in they way drivers navigation our roads today impacting on both safety and convenience. The days of using a street directory are long gone!
Personel tracking for safety in normally unmanned locations.
Asset tracking and control

However, unlike cellphone and AM-FM radio signals which are generally repeated inside tunnels in metro areas, GPS relies on computing locations from multiple signals which are at best, weak in open areas.

There is neither the signal strength nor the computational opportunity to obtain a fix once the signal path is obstructed within tunnels and because of the nature of the computation, these signals cannot practically be repeated within a tunnel.

The Solution - Orolia's Intelligent GPS Repeater Systems for Tunnels

An intelligent GPS repeater system offers a cost-effective positioning solution for GPS-denied locations by creating and artificial sky within the tunnel.

It consists of one Orolia GPS time server with access to an outdoor GPS antenna and a network connection to GPS simulators. In addition to synchronizing the simulator's date/time, the time server also acts an a RINEX server to provide the data about live constellation. Any number of GPS simulators are set to generate signals corresponding to a fixed known location so GPS devices continue to provide a position fix when cross live sky to GPS-denied boundaries.