Intrusion detection system based on speckle pattern analysis

Buried fiber intrusion detection by calculating the changes in the spatial distribution of energy in the output of a multimode optical fiber has been demonstrated. An analysis and experimental demonstrations of the system have been provided in which we observed that by using the very simple technique of speckle pattern analysis using image processing we could detect various intrusions. The system can be used to detect the passage of vehicles and personnel over buried sensing fibers. The non-electrical nature of the sensor would allow it to be undetectable by the intruder, and the low loss nature of fiber optics would allow the signal processing location to be located at a large distance from the actual sensor. The complete hardware utilized in this effort is one that can be realized at low cost. The same technique can be used in many other sensing applications like temperature sensing, pressure sensing, any kind of vibration sensing etc. Further improvements in the design can be planned using neural network and advanced image processing algorithms such that only human intrusions are separated from other (nuisance) intrusion signals.