Prytula M. High-sensitivity radiomeasuring device of the magnetic field induction based on reactive properties of transistor structures

The dissertation work is devoted to increase of sensitivity of radiomeasuring devices of the induction of the magnetic field by using of frequency converters "magnetic induction - frequency" based on reactive properties of transistor structures. Improved mathematical model of radiomeasuring converter of the magnetic field of the radiomeasuring device, which consists of Hall sensor and frequency converter based on two bipolar and field-effect transistors, the circuit implementation of which provided an increase of the sensitivity to 620 Hz/mT of the whole radiomeasuring device in the range of measuring the induction of the magnetic field 0-200 mT. Improved mathematical model of radiomeasuring converter of magnetic field of radiomeasuring device, which consists of two-collector bipolar magnetotransistor and frequency converter based on two bipolar and field-effect transistors, the circuit implementation of which provided a reduction of the error of nonlinearity of the converter to 1.8% and the device as a whole. Improved mathematical model of radiomeasuring converter of magnetic field of radio measuring device, which consists of two-collector bipolar magnetotransistor and frequency converter based on three bipolar transistors, the circuit implementation of which provided an increase of the sensitivity of the radiomeasuring device to 1.25 kHz/mT in the range of measuring the induction of the magnetic field 0-1000 mT. New analytical dependences of conversion functions and sensitivity equations of magnetic field induction radiomeasuring converters are obtained, which differ from the existing ones in that they take into account the influence of the magnetic field induction and frequency, supply and control voltages on the frequency of output oscillations of radiomeasuring converters with differential resistance, which allowed to choose the solution for the development of a highly sensitive magnetic measuring device of the magnetic field induction based on the reactive properties of transistor structures. Three circuit solutions of radiomeasuring frequency converters of the magnetic field induction measuring device have been improved and their characteristics have been experimentally investigated. A radiomeasuring device of the magnetic field induction with increased sensitivity, based on the reactive properties of transistor structures, has been developed. The metrological characteristics of the developed highly sensitive magnetic radiomeasuring device of the magnetic field induction, based on reactive properties of transistor structures, are calculated.