Description: Ported coax or 'leaky cable' detection systems generate an invisible electromagnetic field around the cables which are normally buried in the ground to a depth of about 25cm (although some systems can also be fitted to fences).
Systems require 2 cables 1 to transmit and 1 to receive (although some systems can incorporate both sensors in a single cable). Cables are normally laid 1m apart and a pair will provide a 4m wide detection zone.
If an intruder enters the field he creates a disturbance and an alarm is generated. Intelligent signalling processors eliminate many causes of false alarms such as small animals etc.
Classification: Active - Covert - Terrain Following
Application: Where covert detection is required and where fence mounted protection would be unsuitable.
Advantages: Covert protection and very low vulnerability to defeat, low maintenance requirements and highly resilient to false alarms.
Possible Causes of Nuisance Alarms: Large animals, fences or other moving structures in the detection field, underground streams, flooding.
Methods of Defeat: Deep tunnelling (below 1m) or bridging.