Energetically Passive Fiber-optic Sensor System for the Security Windows of the Buildings

An important element within any buildings, halls and warehouses is protection against intrusions and theft of expensive materials and funds stored in these areas. Currently, there are the many solutions for detecting unwanted intrusion. This article provides a simple solution based on the performed real measurements of the security the perimeter, which is based on fiber Bragg grating that is additionally implemented into structure of the plastic windows. In the case of attempts to break into the protected object, the system records the vibration response in the form of deformation which is transmitted to the Bragg sensor. The article presents two approaches to evaluating the data: the power measurement approach (it uses the point chirped FBG sensor with possible use temperature range from -30 degrees C up to 60 degrees C) and spectral measurement approach (it can monitor up to 80 FBG sensors simultaneously). The advantages of the fiber-optic technology against the conventional solutions are obvious: presented solution is not detectable by conventional methods (EMI-free) and it is energetically passive.