Research And Evaluation On The Hardware Of Electronic Nose

An electronic nose is an instrument, which comprises an array of electronic chemical sensors with partial specificity and an appropriate pattern-recognition system capable of recognizing single or complex odors. An electronic nose consists of hardware and software. The reaction of its sensor array and sample odors is realized in its hardware system. Then the responding signal of the reaction is transmitted by hardware to the computer for analysis and recognition done by its software. The electronic nose will definitely play a significant role in many fields in our lives in future, such as environmental monitoring, detection of explosives, food quality control and etc.. In order to identify the property of the electronic nose and to have a better application in practice, we have to evaluate the system as thoroughly as possible. What's more, the evaluation will give us some experience and suggestion for further development of the next-generation electronic nose. But the research of the evaluation of electronic nose is rare. This assay researches on the hardware of the electronic nose, at first, briefly introduces the formation of human olfaction and the constitution of electronic nose; and then mainly focuses on the realization of the hardware of the electronic nose; at last evaluates the hardware of the ppb (part per billion) electronic nose system as an example.The hardware of the electronic nose can be mainly divided into two parts: the sampling modular and the electronic circuit. The sample odors are sent into the test chamber either in a dynamic or a static way, where the sample molecule and sensor array take reactions. Now the signal of the sensor array is acquired by its electronic circuit and transmitted into the computer. The methods to realize the sampling modular and electronic circuit are of many kinds. The appropriate methods should be chosen according to the specific needs of its application fields.The hardware of the electronic nose can also be evaluated in two ways: separately and generally. The separate evaluating method focuses on the characteristics of each part, in order to evaluate the performance of each part; while the general evaluating method focuses on the characteristics in application, in order to evaluate its performance in the specific application process.