High sensitivity low noise nano-gas sensing device with IoT capabilities

This study demonstrates a novel approach for designing a low noise nano-particle based gas sensing device with IoT capabilities. The system is capable of minimizing cross-talk between multiple channels of amplifiers arranged on one chip using guard rings. Graphene mono-layer is utilized as sensing material and the sensitivity is catalyzed by addition of Gold nano-particles on its surface. The signal from the sensing unit is received by an offset cancellation amplifying system using an SoC approach. Internet of things capability of the sensing device is performed using FRDM K64f micro-controller board which sends message on IBM Bluemix IoT platform when a gas is sensed. The message is received by an application created and sent as an email or message to the user. The paper details the mathematical models of the gas sensing devices, and the interface circuitry that drive the differential potentials, resulting from the sensing unit. The paper presents the middle phase of a long-term project, detailing the design approach of the processing unit within the SOC system and wireless implementation of it. The gas sensor is tested for various sensing configurations. Resistive sensing was found to be sufficient for providing reference data for a sensor matrix to be designed. The change in resistance threshold values are populated in the multi-dimensional matrix. Based on sensed change in resistance values, the gas detected can be identified from the matrix. Sensing data is then sent to IBM Bluemix IoT platform using FRDM K64f development board. The information is sent in a form of packet.