INTRODUCTION: As technology evolves, security becomes focus of attention. Most people think of additional lighting or adding a security camera system. But high value location many want to consider perimeter fencing. Perimeter fencing involve more than just putting a fence up. Patrolling and other traditional methods with sensors and instruments are often unreliable and expensive. Some systems even have so many false alarms causing distrust in the system. For a more reliable perimeter fence, fiber optic sensing cable may be considered. A fence mounted fiber optic sensing cable for vibration detection and a central sensing device analyzes both the magnitude and pattern of the vibration signatures. Fiber optic sensing cable is more Responsive(Low false positive rate due to noise generated by environmental factors), Reliable(High reliability for detection(: Stand alone system, integrated with pan-tilt cameras and other technologies like infrared systems). This presentation on Perimeter fence security system using fiber optic cable explains basics of the system and some examples of real life uses…

1. Perimeter fence security using
fiber optic cable
• Introduction
• Advantages
• Basic Concepts
• Examples

2. Prof. Madhumita Tamhane
O Security needs more than just putting a fence up.
O Traditional methods :
O are often unreliable and expensive.
O may have false alarms.
O cause distrust in system.
Introduction

3. Prof. Madhumita Tamhane
O Fiber optic sensing cable :
O is more reliable perimeter fence.
O is fence mounted fiber optic sensing cable.
O is used for vibration detection.
O uses central sensing device to analyse
magnitude and pattern of vibration
signatures.
Introduction

4. Prof. Madhumita Tamhane
Advantages
O Fiber-Optic security is very difficult to defeat.
O Responsive: Low false positive to noise
generated by environmental factors.
O Reliable: High reliability of intrusion detection.
O (extremely low false negative).
O Accurate.
O Flexible.
O Resistant to environmental effects.
O Requires little or no maintenance.
O Long life.

5. Prof. Madhumita Tamhane
Basic Concept
O System involves:
O A fiber optic cable around the perimeter,
O Laser diode LD feeding the cable
O Coupler
O Photo detector PD.
are

6. Prof. Madhumita Tamhane
Basic Concept
O Laser diode LD feeds fiber optic cable through
optical coupler.
O Coupler splits optical power into fiber loop in two
counter directional paths.
O Two counter directional light packets when
combined, cause interference along the loop.
O The light interference is detected by a photo
diode (PD).
O Under static conditions, interference and its
strength are constant.

7. Prof. Madhumita Tamhane
Basic Concept
O When intruder induced vibration is applied to fiber:
O Refractive index in region of vibration changes.
O Interference and its strength fluctuate.
O Emitted light arrives at vibration point with some
difference in time.
O After passing the vibration point:
O two counter directional light packets are
combined,
O Causes change in interference pattern.
O The light interference is detected by a photo
diode (PD).

8. Prof. Madhumita Tamhane
Examples: Military
O Alarm Processing Unit of highest standards in
probability of detection.
O Low nuisance/false alarm rates.
O Advanced tuning capabilities.
O Optimize detection and tuning according to unique
site conditions.
O High level of security.

9. Prof. Madhumita Tamhane
Examples: Transportation & Aviation
O Theft, sabotage and terrorism are security
concern at airports, rail and sea ports.
O Equipment needs to thrive in very harsh
environments.
O High performance and reliability are expected.
O Airports have radar and radio emissions
over many frequency ranges.
O Electrical or electromagnetic sensors unreliable.
O Sensors highly subjected to electromagnetic
interference.

10. Prof. Madhumita Tamhane
Examples: Transportation & Aviation
O Fiber-optic sensor is not affected by radio
frequencies or electro-magnetic interference.
O Most reliable solutions for perimeter security
applications.

11. Prof. Madhumita Tamhane
Examples: Oil and Gas
O Laser light through sensor is analyzed for
distortion to detect threats.
O Remote capabilities allow alarm processing
units at central location.
O Reduces cost.

12. Prof. Madhumita Tamhane
Examples: Oil and Gas
O Eliminates need for communications and power
in the field.
O Only passive optical components are installed in
the field.
O Insensitive to vapors, fumes, EMI, RFI, lightning
or proximity to electrical cables.
O Environmental conditions such as temperature,
lightning, corrosive liquids and gasses are
irrelevant.
O Ideal choice in these environments.

13. Prof. Madhumita Tamhane
Examples: Electrical / Substation
O Security impacts
reliability of electrical
grid in a city or town.
O Susceptible to
attacks or threat by
terrorist/saboteur.
O Unauthorized access
eendangers lives of
intruders, employees
and inhabitants of
nearby community.
O Optical fiber sensors
are most optimum
solution in this
situation.

14. Prof. Madhumita Tamhane
Examples: Corrections facility
O Located in remote
areas with limited
lightning in security
systems.
O Perimeter security
applications are built
on fiber-optic
intrusion detection
systems.
O Initiates appropriate
and timely response.

15. Prof. Madhumita Tamhane
Examples: Protected Distribution Systems
O Network backbone are vulnerable to intruders.
O This system physically protect passive optical
networks.
O Used to alarm network conduit or raceway.
O Lowest cost.

16. Prof. Madhumita Tamhane
O http://fibersensys.com/security-solutions
O http://discountlowvoltage.blogspot.in/2012/09/perimet
er-fence-security-system-using.html
O http://www.cablinginstall.com/articles/print/volume-
19/issue-3/features/the-use-of-fiber-optics-in-security-
and-surveillance-systems.html
O https://www.rp-photonics.com/fiber_optic_sensors.html
O http://www.sensorland.com/HowPage072.html
Reference