Olfactory detection of methane, propane, butane and hexane using conventional transmitter norms

A Si based four element integrated calorimetric sensor was constructed for olfactory detection of hydrocarbon mixtures up to their lower explosion limit (LEL) concentration. In order to construct a four-wire, inherently explosion-proof transmitter, the power consumption of each sensor was reduced below 50 mW and a sequential read-out scheme was adopted. Olfactory detection is based on the principal component analysis (PCA) and partial least square (PLS) fitting.