Small-Sized Seismic-Acoustic Sensor System Based on MEMS Accelerometer and MEMS Microphone

There are several sensor systems concepts designed based on high performance digital signal processors and high-resolution analog to digital converters, which are capable to act as decentralized sensor system in military and security applications. However, there is also need to design the small-seized, low cost sensor systems which are able to detect events by multiple sensors in particular spot of monitored area and at the same time to be part of the higher structure of multisensor systems. The key part of multisensor systems design is to use the tasks oriented sensors and keep the complexity of sensor system from hardware and software site as simple as it is possible. As a variety and number of sensors used in multi-sensor system increases, there is challenge to achieve the real-time signal processing. The paper deals with the design of acoustic-seismic sensor system based on digital Micro-Electro-Mechanical accelerometer, analog Micro-Electro-Mechanical microphone and 8-bit microcontroller. The main part of the paper is focused on sensor system parameter optimization and design of algorithm for acoustic and seismic events detection and subsequent data transferring for a further signal processing in real-time. In conclusion, outcomes of experiments with designed sensor system are evaluated in terms of the ability to detect seismic and acoustic events in real-time.

I. Introduction

Multi-sensor systems in military and security applications incorporate design of sensor systems, such as inertial sensor systems and methods of signal processing, like their calibration [1], magnetic sensor systems [2], [3] or acoustic and seismic sensor systems [4] which create essential part of multi-sensor systems for detection of events in monitored area.