Method for measurement and nonlinearity correction of microwave powersensor

У дисертацији је развијена и представљена унапређена метода и аутоматизовани мерни систем за еталонирање сензора микроталасне снаге која омогућава еталонирање сензора и истовремено одређивање нелинеарности сензора снаге, узимајући у обзир амплитудску и фреквенцијску зависност нелинеарности. Унапређена метода еталонирања заснива се на примени термисторског трансфер еталона високе линеарности и еталонирању сензора на више нивоа снаге. Процес еталонирања сензора снаге је у потпуности аутоматизован и унапређен применом аутоматизованог мерног система, РС рачунара и софтвера VEEpro. Извршени прорачун мерне несигурности еталонирања сензора и анализа буџета несигурности мерења снаге указују на то да унапређена метода еталонирања омогућава максималну корекцију нелинеарности сензора и доприноси значајном смањењу несигурности мерења микроталасне снаге. Тиме се битно унапређују мерне карактеристике сензора снаге без хардверске или софтверске дораде. Реализована валидација потврђује примењивост и високе перформансе унапређене методе еталонирања. Експериментални резултати мерења доказују постојање значајне зависности нелинеарности сензора од нивоа снаге, али и од фреквенције мерене микроталасне снаге. Тиме су потврђене главна и помоћна хипотеза докторске дисертације. Примена унапређене методе еталонирања може значајно унапредити мерне карактеристике микроталасних ватметара са сензорима снаге и утицати на промену постојећег начина мерења нелинеарности сензора снаге (на једној фреквенцији).U disertaciji je razvijena i predstavljena unapređena metoda i automatizovani merni sistem za etaloniranje senzora mikrotalasne snage koja omogućava etaloniranje senzora i istovremeno određivanje nelinearnosti senzora snage, uzimajući u obzir amplitudsku i frekvencijsku zavisnost nelinearnosti. Unapređena metoda etaloniranja zasniva se na primeni termistorskog transfer etalona visoke linearnosti i etaloniranju senzora na više nivoa snage. Proces etaloniranja senzora snage je u potpunosti automatizovan i unapređen primenom automatizovanog mernog sistema, RS računara i softvera VEEpro. Izvršeni proračun merne nesigurnosti etaloniranja senzora i analiza budžeta nesigurnosti merenja snage ukazuju na to da unapređena metoda etaloniranja omogućava maksimalnu korekciju nelinearnosti senzora i doprinosi značajnom smanjenju nesigurnosti merenja mikrotalasne snage. Time se bitno unapređuju merne karakteristike senzora snage bez hardverske ili softverske dorade. Realizovana validacija potvrđuje primenjivost i visoke performanse unapređene metode etaloniranja. Eksperimentalni rezultati merenja dokazuju postojanje značajne zavisnosti nelinearnosti senzora od nivoa snage, ali i od frekvencije merene mikrotalasne snage. Time su potvrđene glavna i pomoćna hipoteza doktorske disertacije. Primena unapređene metode etaloniranja može značajno unaprediti merne karakteristike mikrotalasnih vatmetara sa senzorima snage i uticati na promenu postojećeg načina merenja nelinearnosti senzora snage (na jednoj frekvenciji).This thesis introduces the developed, improved method and automated measuring system for microwave power sensor calibration and simultaneous determination of power sensor nonlinearity, taking into account its dependence on amplitude and frequency. The novel calibration method is based on the application of high-linearity thermistor power transfer standard and sensor calibration at multiple power levels. The power sensor calibration process is fully automated and improved by applying the automated measuring system, PC and VEEpro software. Performed calculation of the sensor calibration measurement uncertainty and the analysis of power measurement uncertainty budget indicate that the new calibration method allows for the maximum correction of sensor nonlinearity and contributes to significant reduction of the microwave power measurement uncertainty. This considerably improves power sensor measuring characteristics without hardware or software upgrades. Performed validation confirms the applicability and high performance of the improved calibration method. Experimental results prove the existence of significant dependence of sensor nonlinearity on the power level, but also on the frequency of the measured microwave power. This confirms main and auxiliary hypothesis of the thesis. The application of developed calibration method can significantly improve power sensor and power meter measuring characteristics and change the currently used method for power sensor nonlinearity measurement (measurement at a single frequency)

Method for measurement and nonlinearity correction of microwave powersensor

У дисертацији је развијена и представљена унапређена метода и аутоматизовани мерни систем за еталонирање сензора микроталасне снаге која омогућава еталонирање сензора и истовремено одређивање нелинеарности сензора снаге, узимајући у обзир амплитудску и фреквенцијску зависност нелинеарности. Унапређена метода еталонирања заснива се на примени термисторског трансфер еталона високе линеарности и еталонирању сензора на више нивоа снаге. Процес еталонирања сензора снаге је у потпуности аутоматизован и унапређен применом аутоматизованог мерног система, РС рачунара и софтвера VEEpro. Извршени прорачун мерне несигурности еталонирања сензора и анализа буџета несигурности мерења снаге указују на то да унапређена метода еталонирања омогућава максималну корекцију нелинеарности сензора и доприноси значајном смањењу несигурности мерења микроталасне снаге. Тиме се битно унапређују мерне карактеристике сензора снаге без хардверске или софтверске дораде. Реализована валидација потврђује примењивост и високе перформансе унапређене методе еталонирања. Експериментални резултати мерења доказују постојање значајне зависности нелинеарности сензора од нивоа снаге, али и од фреквенције мерене микроталасне снаге. Тиме су потврђене главна и помоћна хипотеза докторске дисертације. Примена унапређене методе еталонирања може значајно унапредити мерне карактеристике микроталасних ватметара са сензорима снаге и утицати на промену постојећег начина мерења нелинеарности сензора снаге (на једној фреквенцији).U disertaciji je razvijena i predstavljena unapređena metoda i automatizovani merni sistem za etaloniranje senzora mikrotalasne snage koja omogućava etaloniranje senzora i istovremeno određivanje nelinearnosti senzora snage, uzimajući u obzir amplitudsku i frekvencijsku zavisnost nelinearnosti. Unapređena metoda etaloniranja zasniva se na primeni termistorskog transfer etalona visoke linearnosti i etaloniranju senzora na više nivoa snage. Proces etaloniranja senzora snage je u potpunosti automatizovan i unapređen primenom automatizovanog mernog sistema, RS računara i softvera VEEpro. Izvršeni proračun merne nesigurnosti etaloniranja senzora i analiza budžeta nesigurnosti merenja snage ukazuju na to da unapređena metoda etaloniranja omogućava maksimalnu korekciju nelinearnosti senzora i doprinosi značajnom smanjenju nesigurnosti merenja mikrotalasne snage. Time se bitno unapređuju merne karakteristike senzora snage bez hardverske ili softverske dorade. Realizovana validacija potvrđuje primenjivost i visoke performanse unapređene metode etaloniranja. Eksperimentalni rezultati merenja dokazuju postojanje značajne zavisnosti nelinearnosti senzora od nivoa snage, ali i od frekvencije merene mikrotalasne snage. Time su potvrđene glavna i pomoćna hipoteza doktorske disertacije. Primena unapređene metode etaloniranja može značajno unaprediti merne karakteristike mikrotalasnih vatmetara sa senzorima snage i uticati na promenu postojećeg načina merenja nelinearnosti senzora snage (na jednoj frekvenciji).This thesis introduces the developed, improved method and automated measuring system for microwave power sensor calibration and simultaneous determination of power sensor nonlinearity, taking into account its dependence on amplitude and frequency. The novel calibration method is based on the application of high-linearity thermistor power transfer standard and sensor calibration at multiple power levels. The power sensor calibration process is fully automated and improved by applying the automated measuring system, PC and VEEpro software. Performed calculation of the sensor calibration measurement uncertainty and the analysis of power measurement uncertainty budget indicate that the new calibration method allows for the maximum correction of sensor nonlinearity and contributes to significant reduction of the microwave power measurement uncertainty. This considerably improves power sensor measuring characteristics without hardware or software upgrades. Performed validation confirms the applicability and high performance of the improved calibration method. Experimental results prove the existence of significant dependence of sensor nonlinearity on the power level, but also on the frequency of the measured microwave power. This confirms main and auxiliary hypothesis of the thesis. The application of developed calibration method can significantly improve power sensor and power meter measuring characteristics and change the currently used method for power sensor nonlinearity measurement (measurement at a single frequency)

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Power sensor nonlinearity contributes significantly to the increase of the microwave power measurement uncertainty. Current methods for sensor calibration do not provide correction of the results, due to the sensor nonlinearity. The paper describes an improved method and an automated measuring system based on it for power sensor calibration that enables the correction of the results, taking into account amplitude and frequency dependent nonlinearity. The novel calibration method is based on the application of high-linearity thermistor power transfer standard. The power sensor calibration process is fully automated and improved by applying the automated measuring system, PC and VEEpro software. Performed calculation of the calibration measurement uncertainty and the analysis of power measurement uncertainty budget indicate that the new calibration method allows the correction of sensor nonlinearity and contributes to significant reduction of the microwave power measurement uncertainty, ranging from 15,8% to 40,5%. Experimental results and validation confirm the applicability of the improved calibration method and prove the existence of significant dependence of sensor nonlinearity on the power level, but also on the frequency of the measured microwave power

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