Nonlinear signal processing for ultrasonic imaging of material complexity/Mittelineaarne signaalitootlus materjali keerukuse kirjeldamiseks ultraheliga

• Published in: Proceedings of the Estonian Academy of Sciences 2010-06, Vol.59 (2), p.108
• Main Authors: Dos Santos, Serge, Vejvodova, Sarka, Prevorovsky, Zdenek
• Format: Article
• Language: English
• Subjects: Materials; Methods; Signal processing; Technology application; Testing; Ultrasound imaging
• ISSN: 1736-6046
• DOI: 10.3176/proc.2010.2.08

Ultrasonic imaging of material complexity is investigated theoretically and experimentally using the concept of symmetry analysis based signal processing in symbiosis with nonlinear elastic wave spectroscopy. These concepts were tested experimentally on several complex media with an advanced electronic system. This system exploits TR invariance, reciprocity, and coded excitation for an accurate extraction of the nonlinear signature of the medium under ultrasonic monitoring. Tested both in the context of the medical imaging of a tooth and in those of nondestructive testing of aeronautic composites, the basis of a new tomographic imaging of material complexity is presented with the help of algebraic concepts describing the TR operators. Key words: nonlinear signal processing, TR-NEWS, symmetry analysis, DORT, echodentography, nonlinear acoustics, coded excitation, complex imaging, solitonic waves. Teoreetiliselt ja katseliselt on uuritud materjali keerukuse kirjeldamist ultraheliga, kasutades siimmeetrilise analmisi moistel baseeruvat signaalitootlust sumbioosis mittelineaarse elastse laine spektroskoopiaga. Neid moisteid kontrolliti katseliselt tanapaevase elektroonse susteemiga mitmel keerukal keskkonnal. See susteem kasutab kodeeritud hairitust keskkonna tapse mittelineaarse autogrammi esiletoomiseks ultraheli abil, latitudes nahtuste muutumatusest ajas pooramisel ja vastastikusest vahetatavusest. Ajas pooratavuse operaatoreid kirjeldavate algebraliste moistete abil on esitatud materjali keerukuse tomograafilise kirjeldamise uue meetodi alused, mida on kontrollitud nii hamba meditsiinilise kirjeldamise kontekstis kui ka aeronautiliste komposiitide mittepurustava katsetusega.