Proposte Di Tesi Di Laurea Magistrale in Ingegneria Elettronica

DESCRIPTION: A 2-D imaging procedure for ultrasonic nondestructive testing has to be realized. It relies on both the use of pseudo-orthogonal sequences and of an inversion procedure made robust by combining the conjugate gradient iterative method with the Total Variation regularization. The effectiveness of the proposed procedure has been verified by experimental results: the overall system proved to be able to detect and locate foreign objects within the inspection area, performing good resolution characteristics. The experiments performed have to allow quantitative evaluation about both benefits and limitations implied by the proposed approach. It is necessary to develop both technical and theoretical aspects. Interesting advantages can be derived from the possibility of attaining a high signal to noise ratio even if low power excitations have been adopted, as demonstrated by previous experiments: if appropriately developed, this possibility can have an interesting impact in the industrial applications of the proposed technique, as it can allow further reductions in the physical dimensions of the ultrasonic devices, and this can lead to much higher flexibility in its practical use in industrial environments. As far as the theoretical aspects are concerned, the work will be aimed to develop computationally efficient deconvolution algorithms needed to adopt the Kasami or Gold codes. This would lead to a further reduction of the cross-talking between different channels while preserving the computational efficiency of the current procedure.