Dergunov O. Computerized cyclic signal analysis system for acoustic testing.

The object of research: the process of cyclic signal analysis in acoustic testing. The purpose of research: efficiency improvement of nonstationary cyclic signal analysis methods and devices in acoustic testing. Methods of research: methods of acoustic testing, measurement theory and information-measurement technologies, methods of probability theory and random processes, mathematical statistics, mathematical and computer modeling, digital signal processing methods, algorithmization and programming. Theoretical and practical results: application of 2? phase measure for instantaneous period values of cyclic signals estimation by the sliding window processing of their phase characteristics is suggested and method for measuring local changes of period is developed; method for adaptive adjustment of sliding window size in median filtration of statistical characteristics is developed to decrease statistics deviation and save it's informative peak values; phase method of acoustic signal segregation is improved by application of signal prior processing by empirical mode decomposition and adaptive median filtration of output circular statistics to increase reliability of signal segregation and accuracy of its time position measurement; methodic of cyclic signal segregation in conditions of limited prior information is developed based on rule of intrinsic mode function selection in empirical mode decomposition; methodic of accuracy increment in measurement of local period changes in cyclic signals is developed; computerized cyclic signal analysis system for acoustic testing is developed and tested on vibration inspection tasks; system could be used for development and testing of new acoustic inspection methods. A subject degree of implantation: are used in the State Enterprise of the Ministry of Defense of Ukraine "Lutsk Repair Plant "Motor", and at the department of information-measuring systems of the National Aviation University. Effectiveness of implantation: significant technical and economic results are received which is to improve efficiency of methods and devices of cyclic signal analysis in acoustic testing. Sphere of use: acoustic testing systems of products in different industries.