Figure 3.

Building blocks for a biologically-inspired architecture for artificial machine olfaction. The first stage delivers odorants to receptors in a way that mimics perireceptor events that improve odor separation. The following two stages are related to generation of high-dimensional response patterns across the sensor array similar to the combinatorial activity across a population of olfactory sensory neurons. The sensor array responses are processed first to compress/remove concentration information and then to extract features that allow several levels of abstraction (clustering, discrimination, and quantification). Finally, distinct patterns for odors are stored for subsequent recognition during the testing phase. Interactions between the recognition and feature extraction steps allow filtering of background signals as well as identification of mixture components. (Adapted from ref (97)).