The need to protect strategically important military and civilian locations from unauthorized entry is increasing. This can be along a sparsely inhabited borders, around the perimeter of busy airports, protecting prisons or around other important objects. Distributed fiber-optic sensing delivers the most effective solution for these applications even in cases where there is no electrical power available.<\/p>\r\n\r\n\r\n\r\n
Perimeter monitoring applications utilize acoustic and vibration-sensitive cables. They register noise and the vibrations caused by approaching objects. In this way, a trespasser can be detected and localized within 5 meters. With the application of two parallel sensor cables, the direction and speed of moving objects can be determined.<\/p>\r\n\r\n\r\n\r\n
False alarms are avoided through the use of appropriate signal filters that suppress common sound and vibration patterns so that only relevant anomalies are processed. In addition to software filtering, the sensor cable can act as a bandpass filter through the proper selection of jacketing materials.<\/p>\r\n\r\n\r\n\r\n
Sensor cables can also be integrated into fencing material in order to detect tampering or an unauthorized breach. Strain-sensitive sensor cables can be used for these applications.<\/p>\r\n\r\n\r\n\r\n