Laser Spectroscopic Trace-Gas Sensor Networks for Atmospheric Monitoring Applications

Laser-based atmospheric trace-gas sensors have great potential for long-term, real-time, maintenance free environmental monitoring in distributed Wireless Sensor Networks (WSN). We are developing a laser based chemical sensing technology with wide-area autonomous wireless sensor networking as the final target. Our prototype sensor measures atmospheric oxygen concentration in the form of a battery powered, handheld unit with power consumption <0.3W, sensitivity of 0.02% in 1 sec, weight of <0.4kg without batteries, low cost, high specificity, and the robustness required for long term sensing applications. We demonstrate gas plume localization and quantification using a prototype three-node sensor network. The technology is modular and can be used for different environmentally important molecules such as CO2, NOx, and methane with exceptionally high specificity.