Autonomous Acoustic/Seismic Networks For Intrusion Detection and Assessment

Passive acoustic and seismic sensors have the unique capability for inexpensive non-line-of-sight (NLOS) detection and identification of vehicle movements as well as human and machine activity. While passive acoustic/seismic sensing does not have the standoff range of radar and IR sensors, it does compliment these technologies by offering coverage in NLOS situations. By networking multiple sensor sites, one can use on-site processing to minimize intemode communications for data fusion to localize the target of interest. Since all acoustic and seismic sources have characteristic directivity responses to their respective noise signatures, the network also offers the ability to observe and identify these characteristics. However, in many perimeter defense situations, a simple detection is all that's really needed. Therefore, the intelligent sensor processing goal is to reduce the false alarm rate in the presence of significant changes in background noise and the environment (wind, rain, etc.). We have developed a generic hardware platform for acoustic/seismic detection and environmental characterization (using temperature, wind, humidity sensors, etc.). We have also developed adaptive models for predicting target detectability in a dynamic environment for performance prediction of the sensor networks. Initial performance tests of the hardware are very encouraging and we expect acoustic/seismic sensor networks and our environmental models to have a wide variety uses in surveillance and intrusion detection.