Neometrix / Fibre-Optic Intrusion Detection Systems / Fibre-Optic Intrusion Detection System / NMX-FID-45

NMX-FID-45 · INTEGRATED-TO-ORDER CLASS — ROUTE · LAY · BASELINE · LISTEN · CLASSIFY · ALARM

Fibre-Optic Intrusion Detection System. A cable that can hear.

Name: Fibre-Optic Intrusion Detection System
SKU: NMX-FID-45

Most intrusion sensors guard a point. A pipeline, a fence line or a cable route is a line, and it can run for a very long way with nobody watching it.

So the system turns one optical fibre into a continuous row of listening points. It sends light down the fibre, listens to what comes back, locates each disturbance along the route, and tells a dig from the weather.

Discuss a fibre-optic detection system Capability note (PDF)

A straight open pipeline trench running away across flat dry ground, with one plain grey steel pipe in the bottom, one thin plain black cable laid in sand beside it, and a small plain grey junction enclosure on a short post at the edge of the trench, and no people

Fig · 01 — A pipeline trench with a sensing fibre laid beside the pipe, and a junction enclosure at the edge of the trench — illustrative render.

The sensor

the fibre itselfpassive along the route

The place

found by echo timeeach event placed on the route

The method

listen, locate, classifythen alarm and record

The record

event, place and timeone record per alarm

Status

integrated to orderno system yet delivered

ISO 9001ISO 14001ITU-T G.652 fibre referenceIEC 60794 cable reference

Overview

Why one fibre can guard a whole route.

Because light sent down a glass fibre leaves a faint echo from every point along it, and a disturbance near the fibre changes that echo.

Fig · 02 — The system in one picture: a pulse sent down the fibre, an echo from every point, and the place read from the time the echo returns.

The cable is the sensor. The unit only listens.

What the system is for

It guards a long line: a pipeline, a fence line, a buried perimeter or a cable route. It reports that something is happening near the fibre, where on the route it is, and what kind of event it looks like.

Why the cable can be the sensor

Why the place is known

The echo from a point farther along arrives later. The time it takes to return gives the distance down the fibre, so each disturbance can be placed on the route without a sensor at that spot.

Why the baseline matters

A route is never silent. Traffic, rain, wind on a fence and nearby plant all leave echoes. The system first listens to each stretch in its quiet and busy states, so an event is judged against what that stretch normally does.

Why telling events apart is the hard part

Detecting a disturbance is the easy half. A person digging, a vehicle passing and a rainstorm all disturb the fibre. The system looks at the shape in place and time to tell them apart, and that is what keeps false alarms down.

Why the unit can sit at a station

The sensing fibre needs no power along the route. The unit sits at a station and does the listening, and long routes are served from stations along them.

The method

Route, lay, baseline, listen, classify, and alarm.

Six steps in a fixed order. The two shaded steps are the ones a quick job skips.

FIG · 02FIBRE-OPTIC INTRUSION DETECTION SYSTEM · ROUTE / LAY / BASELINE / LISTEN / CLASSIFY / ALARM — THE CABLE IS THE SENSOR

The step people underrate is the baseline. A system that has never listened to a stretch of route cannot tell its ordinary noise from a threat.

Fig · 03 — Three events, three signatures: digging, a vehicle and weather — a drawing of the idea, with no values.

1 · Route

The route is walked and the fibre path is chosen, with joints, enclosures and access points planned.

2 · Lay

The fibre is laid in the trench or fixed to the fence, jointed, and tested from end to end.

3 · Baseline

Each stretch is listened to in its quiet and busy states, and its sensitivity is set to suit.

4 · Listen

The unit sends pulses and reads the echoes along the whole route, all day and all night.

5 · Classify

Each disturbance is sorted by its shape in place and time into a dig, a vehicle, a walker or the weather.

6 · Alarm

A real event raises one alarm with its place on the route, and one record is kept.

Work content

What the system contains, element by element.

Read it as a checklist: a system missing a row will buy that row back later, usually as a false alarm nobody trusts.

A single straight run of galvanised steel mesh security fence with one thin plain black cable clipped along its top and a small plain grey junction enclosure fixed to a fence post, on dry level ground, and no people

Fig · 04 — A sensing fibre fixed along the top of a fence, with a junction enclosure at a post — illustrative render.

Element	What it does	What matters
Sensing fibre & cable	is the sensor along the whole route	standard single-mode fibre in a cable chosen for the route and the way it is laid
Interrogator unit	sends pulses and reads the echoes	a specialist item bought in, matched to the route and to the fibres it serves
Joints & enclosures	join the fibre and protect the joints	sealed and kept few, because every joint costs some light
Route survey & laying	put the fibre where it hears best	depth, distance from the pipe or fence, and the ground it lies in
Field power & links	serve any station along the route	power, lightning protection and a link back to the control room
Software & classification	sort events and place them	tuned to each stretch from its baseline, not set once for the whole route
Alarm & integration	pass an alarm to the control room	one alarm with a place, handed to the site's own alarm and camera systems
Data record	keeps every event	place, time, class and the echo behind it, one record per alarm
Procedure	fixes the sequence	route, lay, baseline, listen, classify and alarm, the same for every route
Testing & documentation	prove the system on the route	walk tests and simulated digging at agreed points, and a record the customer can inspect

The element that decides whether the system works is not the unit. It is the laying. A fibre laid where the ground does not carry vibration, or too far from what it guards, will hear a dig and report nothing.

Fig · 05 — One unit, three routes: a pipeline trench, a fence line and a buried perimeter, with the route and the laying changing and the unit staying the same.

Full specification — expand

System	A sensing fibre and cable laid in the trench or fixed to the fence; an interrogator unit at a station that sends pulses and reads the echoes; joints and field enclosures; power and links to serve any station along the route; software that sorts and places events; alarm integration with the control room; a data record; a written procedure; and testing and documentation before handover
The One Idea	The cable is the sensor. Light sent down one fibre comes back from every point along it, so the unit hears a footstep or a spade anywhere on the route and says where
Why The Cable Can Be The Sensor	A pulse of laser light sent down a single-mode fibre is scattered back, very faintly, from every point along the glass, and ground vibration near the fibre changes the echo from that point
Why The Place Is Known	The echo from a point farther along arrives later, so the time it takes to return gives the distance down the fibre and each disturbance can be placed on the route without a sensor at that spot
Why The Baseline Matters	A route is never silent, so the system first listens to each stretch in its quiet and busy states and judges an event against what that stretch normally does
Why Telling Events Apart Is The Hard Part	A person digging, a vehicle passing and a rainstorm all disturb the fibre, so the system looks at the shape of each event in place and time to tell them apart, which is what keeps false alarms down
Why The Unit Can Sit At A Station	The sensing fibre needs no power along the route, so the unit sits at a station and does the listening, and long routes are served from stations along them
Standards	ITU-T G.652 is the public reference for standard single-mode optical fibre, and IEC 60794 is the public reference for optical fibre cables. Neither sets how well a system detects on a particular route: that is shown by the maker's data and proved in acceptance trials on the customer's own route, and this page prints none of it. Approval of the finished system rests with the customer and the authority they name; none is claimed here
Configurations	A pipeline system with fibre in the trench and units at stations, a perimeter system with fibre on the fence or buried round the site, and detection with cameras, where an alarm calls up the nearest camera
Scope Boundary	This is the system that senses along a fibre and reports each event with a place. It is not a fence-mounted point sensor and camera system (see CCTV surveillance system including sensor for protection), not a physical barrier (see crash-rated bollards and vehicle barriers), not a mast that raises a sensor (see telescopic and hoistable mast), and not a leak detector: finding product loss from a pipeline is a different task and is not claimed here
Status	Neometrix integrates fibre-optic intrusion detection systems to order, and no delivered fibre-optic intrusion detection system is claimed.

Configurations

One method, three ways to supply the system.

The method, the record and the baseline rule are shared. What changes is the route and what an alarm calls up.

Pipeline system

Fibre in the trench

Fibre laid beside the pipe, with units at stations along the route and a link back to the control room.

Perimeter system

Fence and buried

Fibre fixed to the fence or buried around the site, with one unit and one alarm point.

With cameras

Detection that calls a camera

An alarm that calls up the nearest camera, so the control room sees what the fibre heard.

Fig · 06 — Three ways to supply the system, one method: a pipeline system, a perimeter system, or detection with cameras.

And the part that is not equipment at all, yet decides all three: the baseline. It fixes what each stretch normally sounds like, so every alarm is judged against its own stretch of route.

Where it is used

Wherever a long line has to be watched.

The common thread is a route too long for guards to walk and too exposed to leave unwatched.

Buried pipelines

Where a pipeline must be warned of digging and heavy plant near it before they reach it.

Site perimeters

Where a long fence or a buried boundary must report where it was crossed, not only that it was.

Cable and utility routes

Where a buried cable or duct run needs the same warning of work going on above it.

Remote, thinly manned routes

Where one alarm point is wanted in place of many, because nobody is near most of the line.

FAQ

Common questions.

Longer answers, for readers who want the reasoning.

Q · 01 How can a glass fibre hear?

A pulse of laser light sent down a single-mode fibre is scattered back, very faintly, from every point along the glass. Ground vibration near the fibre disturbs it a little, and that changes the echo coming back from that point. The unit reads those changes along the whole fibre. This is often called distributed acoustic sensing, and it uses the same kind of fibre that carries telecommunications.

Q · 02 How does it know where the event is?

By time. The echo from a point farther along the fibre arrives later than the echo from a nearer one. The time between sending the pulse and receiving the change gives the distance down the fibre, and the survey of the route turns that distance into a place on the ground. The length of the pulse sets how finely a place can be given. This page prints no distance and no accuracy, because both depend on the unit and on the route.

Q · 03 Why do false alarms matter so much?

A route is never quiet. Traffic, rain, wind in a fence and nearby plant all disturb the fibre. A system that raised an alarm for each would soon be switched off. So the system listens to each stretch first, learns what is ordinary for it, and sorts events by their shape in place and time. A dig stays in one place, a vehicle moves along the route, and weather is faint and everywhere. How well that works depends on the unit, the laying and the tuning, and it is shown by trials on the route, not by a page.

Q · 04 Is this the same as the CCTV and perimeter protection, bollard or mast pages?

No, and the differences are worth stating precisely. The CCTV surveillance system including sensor for protection page is a site system of fence sensors and cameras that watches a point, and the crash-rated bollards and vehicle barriers page is a physical barrier. The telescopic and hoistable mast page raises a sensor on a mast. This page senses along the cable itself, over a long route. It does not replace any of them, and it does not claim what they claim a second time. A detection system and a camera system can also work together, and the third configuration above is exactly that.

Q · 05 What can the system not do?

It reports a disturbance; it does not stop one. A barrier stops a vehicle and a guard stops a person, so the system is the warning and not the protection. It also does not see what caused an event, so a camera or a patrol confirms it. Finding product loss from a pipeline is a different task and none is claimed here. How good the detection is depends on how the fibre is laid, what ground it lies in, and how each stretch was tuned. No detection range, detection rate or false-alarm rate is printed here, and no laboratory accreditation is claimed: this page claims none.

Q · 06 Has Neometrix built one of these?

We would rather answer this plainly than let a page imply otherwise. Neometrix integrates fibre-optic intrusion detection systems to order, and no delivered fibre-optic intrusion detection system is claimed. What stands behind the offer is adjacent: Neometrix offers its own infrastructure protection system of perimeter sensors, cameras and command software (see the CCTV surveillance system including sensor for protection page). The interrogator unit and the sensing fibre are specialist items bought in from specialist makers, not invented. What Neometrix integrates is the system around them: the route survey, the laying and jointing design, the field enclosures, power and links, the control-room integration, the alarm handling, the procedure, the testing and the records. So the honest position is that the system is integrated to order, the neighbouring discipline is in the building, and the first system of this exact kind will be built around the customer's own route rather than lifted off a shelf.

Q · 07 Which standards apply, and who sets the performance?

ITU-T G.652 is the public reference for standard single-mode optical fibre, and IEC 60794 is the public reference for optical fibre cables. Neither sets how well a system detects on a particular route: that is shown by the maker's data and proved in acceptance trials on the customer's own route, and this page prints none of it. Acceptance of the finished system, including its proving walks before handover, rests with the customer and whatever authority they name.

Q · 08 What do you need from us to quote?

Six things, and most of them describe your route rather than the system. First, the route: what it is, how long it runs and how the ground lies. Second, whether the fibre will be buried, fixed to a fence, or both. Third, whether a fibre already laid along the route can be used. Fourth, the alarms you need: what must be detected and how it must be reported. Fifth, the control room: the alarm and camera systems the new one must join. Sixth, the site: access, power along the route and who will run it. From that we come back with a route plan, a written method you can check, and a budgetary price.

The neighbouring protection pages, and how they differ from this one.

Three neighbours: a point-sensor system, a barrier, and a mast.

↗ Sensors at a point

CCTV Surveillance System Including Sensor for Protection

Fence sensors, cameras and command software for a site - it watches a point, it does not sense along a cable.

↗ A barrier

Crash-Rated Bollards and Vehicle Barriers

A physical barrier that stops a vehicle - this page warns, it does not stop.

↗ A raised sensor

Telescopic and Hoistable Mast

Raises a sensor or camera on a mast - the fibre needs no mast, because the cable is the sensor.

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Get a quotation

Tell us the route, the laying,
and the alarms.

The projects desk replies within two working days with a route plan, a written method you can check, and a budgetary quotation. Write to [email protected] or use the form.

Enquire — fibre-optic detection Capability sheet (PDF) +91 7777 876 876

ISO 9001 / 14001 INTEGRATED-TO-ORDER CLASS — FIBRE-OPTIC INTRUSION DETECTION SYSTEM ROUTE · LAY · BASELINE · LISTEN · CLASSIFY · ALARM — THE CABLE IS THE SENSOR ENGINEERED IN NOIDA · INDIA