The use of composite fence with integrated sensors in security systems

摘要

This paper presents possibilities of using the composite fence in the security systems. The fence made entirely of dielectric materials is neutral for electromagnetic waves. Thus, the fence does not introduce disturbances in propagation of electromagnetic waves. The use of composite fences reduces reflections of electromagnetic waves which cause negative effects on fence sensors, microwave barriers and radars. Additionally, the sensing part of the fence sensors can be integrated in the composite fence structure. Thus, the detecting elements mounted on the fence are invisible for potential intruder. This paper presents the composite fence with integrated fiber for fiber optic sensors. By arranging the fiber into fence grid it is possible not only discreet installation of the sensors, but also better transfer movements of the fence to sensitive optical fiber. By using the fiber as a sensing element the whole fence remain dielectric. Thereby obtaining a fence entirely transparent to electromagnetic waves which is also monitored for forcing attempts. Another way to use the dielectric properties of the composite fence is possibility of use electromagnetic sensors. Installation of the electromagnetic sensor directly on the fence allows to create a monitored zone in the close surroundings on both sides of the fence. The use of two types of sensors based on different physical phenomena provides an improvement in the detection properties of the entire security system by reducing the number of false alarms and increasing level of safety by increasing the probability of detection an attempt to force the fence.