GPS / GNSS Over Fiber In-Building Distribution System

The GPS / GNSS Over Fiber In-Building Distribution System is designed to extend satellite positioning signals into locations where normal GPS and GNSS reception is weak, blocked, or completely unavailable. This includes underground facilities, parking structures, tunnels, basements, large commercial buildings, transportation hubs, data centers, hospitals, warehouses, public safety facilities, and other indoor GNSS shadow areas.

Outdoor GNSS signals are often blocked by concrete, steel, underground structures, and large buildings. This system solves that problem by receiving GNSS signals from an outdoor antenna, processing them through a central master unit, and distributing synchronized GNSS service to multiple indoor remote antenna units over fiber optic cable.

How the GPS / GNSS Over Fiber System Works

The system is based on a central Master Unit, also called the MU, and multiple Remote Units, also called RUs. A GNSS receiving antenna is installed outside the building where it has clear visibility to the sky. The GNSS signal is received by the MU and then distributed through fiber optic links to indoor RU antenna units.

Each RU rebroadcasts the GNSS signal in its local indoor service area, allowing GPS and GNSS-enabled devices to receive positioning information even when they are located inside a building or underground area.

The MU includes multiple optical SFP ports, allowing connection to several RU branches. The RU units can also be cascaded, making it possible to expand the system across multiple floors, hallways, rooms, parking levels, or indoor zones.

Key Benefits

• Extends GPS / GNSS service into indoor and underground areas
• Supports L1 and L5 GNSS service bands
• Fiber optic distribution for long-distance, low-loss signal transport
• Supports up to 10 km optical transmission distance
• One MU can support up to 32 RU remote antenna units
• 8 optical branch ports on the MU for flexible system design
• RU cascade support for multi-floor and multi-zone installations
• Designed for public safety, logistics, transportation, emergency response, and smart building applications
• Ideal for GNSS shadow areas where satellite signal cannot penetrate

Typical Applications

Underground Parking and Indoor Navigation

In underground parking garages, GPS signals are normally unavailable. This system allows vehicles, mobile phones, and navigation devices to continue receiving GNSS positioning information, helping drivers locate routes, parking areas, exits, and pickup locations.

Public Safety and Emergency Response

For emergency response teams, indoor location information can be critical. The system helps improve location awareness in buildings, underground facilities, tunnels, and large public spaces where standard GPS coverage is not available.

Transportation and Logistics

Warehouses, logistics centers, loading docks, and transportation facilities can use indoor GNSS coverage to help track vehicles, assets, equipment, and personnel in areas where outdoor satellite signals are blocked.

Smart Buildings and Smart City Infrastructure

The system can be used as part of a smart building or smart city infrastructure where indoor positioning, asset tracking, location-based services, and safety systems require reliable GNSS availability.

Security, Finance, and Critical Infrastructure

GNSS timing and location data may be required in secure facilities, financial institutions, data centers, and other critical infrastructure environments. This system helps bring GNSS availability into protected or shielded indoor areas.

System Architecture

A typical installation includes one outdoor GNSS antenna, one 1RU rack-mount MU master unit, fiber optic links, and multiple indoor RU antenna units. The outdoor antenna receives GNSS satellite signals and sends them to the MU. The MU distributes the signal through its optical SFP ports to the RU units installed throughout the building.

Each RU provides GNSS coverage for its local service area. Additional RUs can be connected using cascade ports, allowing the system to be expanded in a logical and cost-effective way.

Why Use Fiber for GPS / GNSS Distribution?

Fiber optic cable is ideal for distributing GNSS signals inside large facilities because it provides long-distance transmission, low loss, electrical isolation, and immunity to electromagnetic interference. Unlike coaxial cable, fiber can carry the signal over long distances without the same level of RF loss, making it suitable for large buildings, campuses, tunnels, and multi-level facilities.

Using fiber also allows the central GNSS equipment to be installed in a secure rack room while the remote antenna units are placed exactly where indoor GNSS coverage is needed.

Installation Example

A GNSS antenna is mounted on the roof or another outdoor location with clear sky visibility. The antenna connects to the MU master unit located in the equipment room. From the MU, fiber optic cables are routed to RU units installed inside the building. The RU units provide localized GNSS signal coverage for indoor areas such as parking levels, corridors, warehouse zones, emergency response areas, or transportation terminals.

Ideal For

• Underground parking garages
• Hospitals and medical campuses
• Airports and transportation terminals
• Warehouses and logistics centers
• Shopping malls and large commercial buildings
• Public safety and emergency response facilities
• Tunnels and underground transportation systems
• Data centers and secure facilities
• Smart city and smart building infrastructure

F-GNSS-TX  - GPS/GNSS FiberLink Master Unit
F-GNSS-RX  - GPS/GNSS FiberLink Remote Unit
F-GNSS-TX/RX -  GPS/GNSS FiberLink Indoor Distribution Kit

Specifications