中文
English
Fiber Optic Perimeter Boundary Alarm Systems
System Overview
The fiber optic Perimeter boundary alarm system is a new generation of security system. The system with optical fiber sensing technology and provides security monitoring up to 40 kilometers away without any outdoor active devices (no power supply). It is especially suitable for long-distance and large-scale area defense.
Figure 1: Equipment appearance and geographical information show interface of intrusion alarm system
The system can effectively provide real-time and reliable intrusion alarm information instantly. When an intrusion occurs and the optical cable vibrates slightly through stepping, touching, shaking, squeezing, etc., the system will alarm immediately and locate the alarm location accurately.
Figure2：Border defense
Applications
The optical fiber perimeter boundary alarm system can lay the sensing optical cable near the monitoring perimeter boundary by hanging the network or burying it in the ground. It is sensitive to stress changes in the external environment. When an intrusion occurs and causes vibration , the system generates an alarm via signal processing. And the GPS coordinates of the intrusion location are displayed on the geographic information system software interface in real time.
The system has a broad application market and huge military and economic value. It can be widely used in:
| Military Sectors | Borders, military bases, military communication optical cables, military factories, military airports, military warehouses, barracks, etc. |
|
Civil Sectors |
Monitoring and protection of important economic targets such as government facilities, airports, nuclear power plants, reservoirs, large dams, chemical plants, prisons, etc. |
Figure 3: Deployment of perimeter boundary and important areas
System Structure
Optical fiber perimeter boundary alarm systems have 2 types: position type and defense zone type, the structures are as below:
Figure 4: Accurate Position Type
This type distributes over the entire defense area via a sensing optical cable without adding any intermediate equipment. When an intrusion alarm occurs, the system can quickly locate the intrusion location and display it on the system software interface in real time, while show the GPS coordinates of the intrusion point. The positioning accuracy can reach up to 10 meters.
Figure 5: Defense Zone Type
This type physically divides the defense area into multiple areas, the each area is separated by a terminal box and has independent alarm. When an intrusion alarm occurs, the system can quickly locate the intrusion zone.
System principle
The optical fiber micro-vibration perimeter boundary alarm system is based on optical fiber distributed micro-vibration sensors. The system working principle flow chart is shown in Figure 6.
Figure 6: Flow chart of system working principle
The optical fiber perimeter boundary alarm system adopts the physical principle of laser interference. The laser propagates in the optical fiber interferometer. External micro-vibration acts on the sensing optical cable, which will cause the optical fiber to deform. The deformation of the optical fiber changes the phase of the laser transmission through the elastic-optical effect, thus causing interference signal.
Figure 7: Schematic diagram of optical fiber affected by vibration
System Features
No need power supply, using the optical and the monitoring distance can be up to 40 kilometers.
High alarm sensitivity, accurate positioning, the positioning accuracy can reach up to 10m
Supported by quantitative experimental data, multi-parameter intelligent analysis, false alarm rate ≤3 times/day
It can be integrated with the user’s existing monitoring system and work synchronously, such as: precise positioning of the intrusion location and linkage the monitoring cameras, etc.;
Suitable for complex terrain and harsh climates, no part prone to aging, high reliability, easy to maintain, instant alarm when the optical cable is broken and can be reused via simple repair;
Apparatus are easy to install, simple to operate, stable and reliable
High cost-effectiveness, independent intellectual property rights, patented technology.
System parameters
System parameters are as the following:
| Monitoring length | Minimum length | N/A | |
| Maximum length | 40km | ||
| Positioning accuracy |
Defense Zone type: Depends on Defense Zone length
|
||
| 10/20/50/100m
Accurate Position Type:10/20/50/100m |
|||
| System sensitivity | The sensitivity of vibration which generates alarms can be adjusted according to on-site conditions to effectively filter natural vibration signals such as wind, rain, and vehicle passing. | ||
| False alarm rate | ≤ average 3 times/day | ||
| Monitoring and data processing system | Hardware | PC（CPU：4core/ Memory：2GB） | |
| OS | Windows XP/win 7 | ||
| Software | full functional graphical user interface | ||
Applications Cases
After years of R&D and extensive practice, the fiber optic perimeter boundary alarm system has been successfully used in a variety of scenarios and has achieved good effect in practical applications.