Metal oxide SAW E-nose employing PCA and ANN for the identification of binary mixture of DMMP and methanol

An Electronic nose (E-nose) made up of an array of metal oxide thin film based SAW sensors is proposed as a detection system for the binary mixture of DMMP (simulant of nerve agent) and methanol at room temperature. The SAW devices are one port surface acoustic wave (SAW) resonators having center frequency of 433.9 MHz. The E-nose sensor array has SAW sensors coated with four different chemical sensitive coatings of ZnO, TeO2, SnO2 and TiO2 in order to recognize the individual components in a binary mixture of DMMP (in ppb levels) and methanol (in sub ppm levels). Principal Component Analysis (PCA) as a data pre-processing technique and Artificial Neural Network (ANN) as a pattern classification technique have been applied for obtaining a clear discrimination and correct classification.