COMPARISON OF TWO SAMPLING METHODS FOR SINE WAVE MEASUREMENT

摘要

Two methods, one approximate and one theoretically (mathematically) exact, for calculation of parameters of measured low frequency sinusoidal signal are thoroughly studied and compared. Both methods perform sampling of measured signal by HP 3458A Digital Multimeter in DC mode in order to achieve the best possible accuracy. Comparison was made firstly on calculated, ideal sinusoid (computer simulation) what has shown us theoretical limits of accuracy due to calculating inaccuracy and approximations. Then a series of measurements in real, laboratory conditions was made to confirm or refute theoretical foresights. For both methods, advantages and disadvantages are noticed and main influences on the final result uncertainty are explained.