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).