Моrozova M. Research of efficiency of discrete Fourier transform’s using for phase measuring

The object of research: process of determination of informative parameters (phases’ difference and amplitude) of harmonic signals with DFT application. The purpose of research: to increase the efficiency DFT using in phase measuring for providing of necessary accuracy of measuring results of informative parameters of signals. Methods of research: digital signal processing, computer modeling, and theories of: probability and mathematical statistics, signals, spectrology, informative-measuring systems. Theoretical and practical results and innovations: a mathematical model is offered for phases’ difference measuring of harmonic signals for determination of the most effective approaches to provide necessary measuring accuracy; first time the investigation of measuring errors, wich are conditioned by the subsampling of harmonic signals with application of DFT, is presented, and maximum value of subsampling coefficient is defined; the structures of devices (such as calibrator, phase-meter, workstation of metrologist) with application of DFT, are developed; the models of virtual instruments of devices and virtual educational laboratory are developed. A subject and degree of introduction: the results of research were implemented in the educational process NTUU “KPI” and are recommended to use in developing of metrologist’s workstations and in instrument-making industry. The sphere of application: phase measuring.