Zero-Power Seismic Sensors for Discrimination of Foot and Vehicle Traffic

A low-power (<10 mW) analog sensor capable of detecting ground vibration (i.e. seismic) signals and identifying their source possesses significant relevance in the field of national security. Very low power consumption by the sensor will allow long-term remote operation without battery replacement. A published frequency-domain algorithm was adapted for discrimination of foot and vehicle traffic. For simplicity, the scope of the project is limited to analog circuitry, eliminating the need for digital signal processing. Various sensor designs, including geophone and piezoelectric sensors were tested for comparison. The accuracies and sensitivities inherent in the sensors were determined through observation in field testing, and these observations assisted in determining the appropriateness of the various sensors for the project at hand. The results of these tests were compared with published results. A completed low-power seismic sensors would be suitable for integration into Distributed Sensor Networks, where they can be used to monitor foot and vehicle traffic in remote areas.