Design And Development Of Node Application In Optical Link Monitoring System

Optical link monitoring system is a new-type perimeter defense system. This system is centered around advanced Φ-OTDR distributed optical fiber sensing technology and combined with environmental parameters measurement technology and video monitoring technology, which can collect information from environment or monitoring targets in real time, analyze and process the information using the embedded system, detect the external invasion and transmit the invasion records to the server through wireless communication network eventually. This paper designes the optical link monitoring system aiming at building sensor, having broad application prospects and important socio-economic value in the security field.In this paper, main work is to design and develop the GUI application of sink node and management node in optical link monitoring system, aiming at enhancing the user interaction experience and realizing the intelligent, information and network mangerment system.Sink node detects vibration, locates invasion and starts the alarm accurately and rapidly based on the distributed optical fiber sensing technology and FPGA data acquisition technology with high speed and high precision, in which ARM acted as the core. The sink node software is designed with strong capability and friendly user interface by Qt4 and has many functions, such as data communication between ARM and FPGA, vibration signal location processing, Sqlite database management, Sockct network communication, user authorization management, histogram statistic and map display for invasoion records. In addition, to reduce the effects of environmental factors on detection results and improve the alarm accurancy, the environmental parameter is brought into location algorithm as a filter coefficient to set the alarm threashold dynamically.Management node, usually PC, is connected with multiple sink nodes through network, builds database to store alarm history and realizes the unified management of several areas. The management node software is designed with a modular structure including network communication module, map display module, database management module and other security means integration module. Video linkage module, an example of other security means integration module, takes advantage of network DVR provided by 3rd party to bring up the video near the alarm points, which is easy to verify the effectiveness of the alarm.Practical field test shows the node software has achieved all the targets and been successfully applied in the practical perimeter defense system with good robustness and reliability.