DAS · PIDS · critical infrastructure
Fibre-optic perimeter security — event location and classification
A passive sensing cable mounted on a fence, buried in the ground or used in a hybrid arrangement can form a continuous detection line. A DAS interrogator converts vibration into a location and classified alarm.
fence or buried installationpeople, vehicles and excavationCCTV / VMS / C2passive sensing cable
DAS does not create an image or identify a face. It measures dynamic strain transferred to the optical fibre. The event class is an outcome of signal analysis, zone configuration and validation in the actual environment.
The range of the platform is not a guaranteed detection range for every intruder type. Performance also depends on the ground, fence, cable construction, mounting method, vibration background and required event classes.
What can create a DAS signature?
The catalogue of target events and disturbances should be defined before the pilot.
Fence climbing and cutting
A cable attached to the fence records structural vibration, but also receives wind and loose-component noise.
Person or vehicle movement
A buried cable can record ground vibration; performance depends on soil, burial depth and mechanical coupling.
Excavation and under-digging
Manual or mechanical excavation produces signatures that require validation at the target site.
Interference with linear infrastructure
One sensing route can cover a fence, boundary or approach to a protected asset.
Three ways to deploy the sensing cable
The configuration follows the threat scenario, not one universal distance figure.
| Phenomenon / objective | Technology | What it provides | INTERLAB portfolio |
|---|
| cutting, climbing, impact | fence-mounted DAS | location of structural vibration and event class | ATLAS, QuantX, iDAS-MG |
| pedestrian, vehicle, excavation | buried DAS | signature of movement transferred through the ground | ATLAS, QuantX, iDAS-MG |
| alarm verification | DAS + CCTV/VMS | time, zone, class and confidence supplied to the operator | analytics and integration layer |
| two protection lines | hybrid arrangement | separate fence and buried approach zones | multi-channel DAS interrogator |
Important: We do not promise “zero false alarms”. Nuisance alarms are reduced through zoning, classification, a disturbance library, seasonal validation and fusion with other sensors.
DAS interrogators available from INTERLAB
Compare fibre count, topology, data access, integration and installation requirements.
DASOptaSense ATLAS
A multi-channel DAS platform for extensive assets and integration with external systems.
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DASOptaSense QuantX
Quantitative DAS for long boundaries, advanced analysis and applications that require access to measurement data.
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DASSilixa iDAS-MG
A flexible platform with selectable measurement configurations for non-standard applications.
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CategoryDAS acoustic and vibration sensing
Current DAS interrogators and related equipment in the INTERLAB catalogue.
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ApplicationPipeline monitoring
DAS for protecting linear assets against interference and dynamic events.
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CategoryMonitoring systems
Explore DAS, DTS, DSS, OFDR and FBG equipment available from INTERLAB.
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From sensing cable to a validated alarm
Classification should be demonstrated under the target-site conditions.
Define event classes
Separate targets — person, vehicle and excavation — from rain, wind, animals and movement outside the zone.
Select the installation
Fence, buried and hybrid arrangements require different cable constructions and mounting methods.
Collect representative data
Target events and background conditions create the ground truth used to configure the detectors.
Accept the system
Detection, nuisance-alarm and integration metrics relate to the agreed acceptance test.
Frequently asked questions
How does DAS detect an intruder?
It records vibration transferred from the fence or ground to the fibre. The system locates the signal and analyses its features for classification.
Must the cable be mounted on a fence?
No. It may be attached to a fence, buried or used in a hybrid arrangement.
Can the system interface with cameras?
Yes. It can provide the zone, time and event class to CCTV, VMS or C2 according to the integration design.
Is field power required?
The sensing cable is passive. The interrogator, computer and other electronics are located at a technical site.
Can zero false alarms be guaranteed?
No. They can be reduced through design, classification and validation, but defensible metrics must come from testing the specific installation.
Is existing fibre sufficient?
It may be useful, but the route, fibre quality, spare-fibre availability and mechanical coupling to the protected zone must be confirmed.
Select DAS by perimeter length, topology and event classes
Send us the perimeter geometry, ground or fence type, available fibres, target classes and disturbance sources.
Technical sources: OptaSense — intrusion detection · OptaSense ATLAS · OptaSense QuantX
