Радіовимірювальні перетворювіачі вологості на основі МДН-структур

Abstract

The thesis is devoted to the development of the radiomeasuring humidity transformer for the clean room’s air. As the primary information converter is offered to use two-gate humidity-sensitive MOSFET. The secondary converter is offered the using of the radiomeasuring humidity transformer based on self-generating structures with negative resistance, which are using the principle of transformation „quantitative sign of measurand - frequency informative signal”. The influence of humidity on electrophysical parameters MOSFETs with humidity-sensitive porous silicone-oxide layer is considered in the thesis. The analytical and graphic expressions of the active and reactive resistances and equivalent capacitance of theMOSFET are got as a result of mathematical design. On the basis of primary humidity transformer’s mathematical model the conclusion was done about expedience of their use for the generating secondary humidity transformers for the systems of clean rooms, which own a high sensitiveness and stability to the hindrances of the information signal, and can be used as a FM-modulator in the in the wireless information systems. The construction of the microprocessor device for the measurement of the clean room’s air humidity is offered, which has improved firmness to the hindrances by using of frequency transformation method, and allowed application of the secondary transformer as FM-modulator of the transmitter part of device.