An on-line water monitoring system using a smart ISFET array

In this work we present a new on-line water pollution monitoring system. The system includes a smart array of ion-selective field effect transistors (ISFETs) as a front-end and also at post-processing stages in order to transmit the stored measures of ion concentrations. The intelligence in the smart sensors is provided by a blind source separation (BSS) algorithm which continuously learns from measures of how to detect the ion concentrations available in the mixed signal observed in the array's output. The computational simplicity of the BSS algorithm and its capability of continuous learning from the environment, allow the design of a low-power, cheap and small system that monitors water in real-time, and is a contrast to the classical off-line approach based on a water analysis of the extracted measures in the laboratory. The work is in progress, as part of the SEWING project (IST-2000-28084).

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