Odor sensing system

An odor sensing system for discrimination of closely parallel odors, said system comprising:

• a sample vapor supply line having a gas supply means to supply gas flow through said system, a mass flow controller connected to said gas supply means to maintain said flow constantly, a cleaning circuit including a switch-over means connected to said mass flow controller allowing said gas flow to pass through said circuit, and a sampling circuit connected to said mass flow controller, said switch-over means switching between said cleaning circuit and said sampling circuit, said sampling circuit including a plurality of sample vapor generators selectively allowing said gas flow to pass therethrough to generate a sample vapor therein,
• a signal output line connected to said sample vapor supply line having a plurality of gas sensors to convert said plurality of sample vapors received from said line to a plurality of pattern signals;
• and
• a recognition line connected to said signal output line to receive said plurality of signals therefrom, said recognition line having distinction means to calculate a respective subtraction between said signals to distinguish differences therebetween, and a discrimination means connected to said distinction means to discriminate odor included in said sample from said subtracted signals.