Signal processing

Systems for non-destructive testing of materials, in particular materials used for scanning, and subsequently to detect defects in the material are tested. For this reason, one part of the research department focused on the development of techniques for noise reduction, defect detection and classification of detected services. The main fields of our research are ultrasonic signals.

In general, the ultrasonic testing is used for flaw detection and localization in tested materials where the flaws in materials are characterized in measured ultrasonic signals by faults echoes. In the case of materials with coarse - grained structure the ultrasonic signal contains undesirable echoes caused by the scattering from these grains considered as a noise. This source of noise makes the flaw detection more difficult. The efficient methods for noise reduction have to be used. The measured ultrasonic signal can be representing in the following form:

Application of advanced signal processing methods, which we have developed our research may be deprived of the resulting signal noise. The resulting signal is then free of noise and echoes representing defects can be successfully detected. Signal after the application of discrete wavelet transformation method is shown here:

Noise reduction methods are the group method that are preliminary implemented in all our developed systems.