FIBER OPTIC SENSING
Sensing Technologies

- Point and Distributed Sensing
- Full-Service Solution Provider
- Independent Fiber Optics Expert
- Own Production Facilites
- In-House R&D and Testing Center

Technologies Overview
Fiber bragg grating
A Fiber Bragg Grating (FBG) is a microstructure with a few millimeters length within an optical fiber.
Distributed Acoustic Sensing
Distributed Acoustic Sensing (DAS) relies on Rayleigh backscatter, which interacts with the optical fiber, exposed by acoustic waves.
Why Fiber Optics
Lifetime
Almost no maintenance. Cable lifetime >20 years
Passive Sensor
No electrical power at the measurement point
Long distance
Remote monitoring (50 km and more)
High sensitivity and accuracy
At sensing point Insensitive lead in to reduce disturbances
Harsh and explosive environments
Resistant to corrosion, lightning, etc.
Immune to EMI
Electromagnetic interference
FBG Sensing
A Fiber Bragg Grating (FBG) is a microstructure with a few millimeters in length.
Fiber Bragg Grating
Vibrations will result in s strain change/wavelength shift of FBGs which are integrated every X meter.
- Point sensitive FBGs allow a resolution from centimeters to meters
- Up to 200m per channel / 1,6km per interrogation unit
- Cost effective for medium sized lengths compared to DAS systems
System
Quasi distributed
pinpoint perimeter system
- Pin point - Point sensitive FBGs allow local resolution of +- 5m
- Up to 200m per channel / 1,6km per interrogation unit
- Cost effective for medium sized lengths compared to DAS systems
- Fence based system

Case Studies
Canara bridge
- NBG provided system design / installation support and comissioning of FiberGuard system
- Integration with 72 video cameras (37 robotic ones) and automatic perimeter lighting
- Security alerts within 5 sec. of attempt and accuracy of 8 meters
- Keyprocessor access control system / Satel security alarm system / Commend intercom system
GMÜND
- 500m PeriGuard Fence based installation
- 200m FBGuard Fence based installation
- Roads and Structural Health Monitoring, Cabinet / manhole monitoring, Temperature sensing
DAS Sensing
A Distributed Acoustic Sensing (DAS) is a microstructure with a few millimeters in length.
Comparison

David Laister
Fiber Optic Sensing Specialist.
“Challenge me with your project”