Optically modulated high-sensitivity heterostructure varactor

The selection of the optimal sensors to use in an electronic nose is fundamental to the success or failure of any particular olfactory system in a certain application. The experimentation and characterization of gas sensors require complex electronic noses designed for the specific sensor array under test. The absence of design generalizations and standard interfaces in artificial chemical sensing systems is a well-known problem usually leading to the re-calibration of the olfactory system whenever a sensor has to be substituted. Bigger problems come up when the migration to sensors based on a different principle is required (e.g. from resistive polymeric sensor to mass-variation QCM sensor); this necessity involves the re-design of part or even the whole olfactory system forcing research groups to great efforts in system design and software programming. In this paper, a solution to standardize gas sensors and electronic olfactory systems is presented.