Proceedings Article | 23 May 2011
Proc. SPIE. 8017, Detection and Sensing of Mines, Explosive Objects, and Obscured Targets XVI
KEYWORDS: Sensors, Fourier transforms, Interference (communication), Data acquisition, Transducers, Signal processing, Analog electronics, Acoustics, Signal detection, Smart sensors
Unattended ground monitoring that combines seismic and acoustic information can be a highly valuable tool in
intelligence gathering; however there are several prerequisites for this approach to be viable. The first is high
sensitivity as well as the ability to discriminate real threats from noise and other spurious signals. By combining
ground sensing with acoustic and image monitoring this requirement may be achieved. Moreover, the DS Sentry®provides innate spurious signal rejection by the "active-filtering" technique employed as well as embedding some
basic statistical analysis. Another primary requirement is spatial and temporal coverage. The ideal is
uninterrupted, long-term monitoring of an area. Therefore, sensors should be densely deployed and consume very
little power. Furthermore, sensors must be inexpensive and easily deployed to allow dense placements in critical
areas. The ADVIS DS Sentry®, which is a fully-custom integrated circuit that enables smart, micro-power
monitoring of dynamic signals, is the foundation of the proposed system. The core premise behind this technology
is the use of an ultra-low power front-end for active monitoring of dynamic signals in conjunction with a highresolution,
Σ Δ-based analog-to-digital converter, which utilizes a novel noise rejection technique and is only
employed when a potential threat has been detected. The DS Sentry® can be integrated with seismic accelerometers
and microphones and user-programmed to continuously monitor for signals with specific signatures such as impacts,
footsteps, excavation noise, vehicle-induced ground vibrations, or speech, while consuming only microwatts of
power. This will enable up to several years of continuous monitoring on a single small battery while concurrently
mitigating false threats.
