A selection of our members:
1. Valle, S., Zanzi, L., Rocca, F., 1999, Radar tomography for NDT: comparison of techniques, Journal of Applied Geophysics, 41, 259-269.
Paper #1 is a discussion supported by experimental tests about high resolution radar tomography on building elements like walls or pillars. Advantages and disadvantages of algorithms for traveltime tomography, amplitude tomography, migration and diffraction tomography are discussed and compared with particular attention to resolution and stability issues.
2. Valle, S., Rocca, F., Zanzi, L., 2000, Diffraction tomography through phase back-projection, in Dermanis, A., Grun, A., Sanso', F., Eds., Geomatic Methods for the Analysis of Data in the Earth Sciences, "Lecture Notes in Earth Sciences", Vol.95, 229-256.
Paper #2 illustrates the theory of diffraction tomography, presents an algorithm for diffraction tomography through phase back-projection and shows its potential on laboratory and on-site data.
3. Valle S., Zanzi, L., Sgheiz, M., Lenzi, G., Friborg, J., 2001, Ground Penetrating Radar antennas: theoretical and experimental directivity functions, IEEE Transactions on Geoscience and Remote Sensing, Vol.39, N.4, 749-759.
Paper #3 is a theoretical and experimental contribution to the problem of predicting the antenna directivity function. The theoretical contribution consists of a numerical solution applicable to both near and far field conditions. The experimental contribution consists of laboratory measurements of near and far field directivity functions of real antennas on dry and saturated sand. Experimental results are then used to discuss the numerical approach.
4. Dell’Acqua, A., Sarti, A., Tubaro, S., Zanzi, L., 2004, Detection of linear objects in GPR data, Signal Processing, 84, 785-799, doi: 10.1016/j.sigpro.2003.12.010.
Paper #4 describes a semi-automatic algorithm for the detection of linear scattering targets, e.g., pipes or concrete reinforcements, in 3D GPR data. The algorithm is based on the 3D Radon Transform. Reliability and robustness of the method are discussed with synthetic and real data tests.
5. Zanzi, L., Lualdi, M., 2010, Analysis of Approximations and Aperture Distortion for 3D Migration of Bistatic Radar Data with the Two-Step Approach, EURASIP Journal on Advances in Signal Processing, vol. 2010, Article ID 192378, 9pp., doi:10.1155/2010/192378.
Paper #5 is a discussion about a fast algorithm for 3D migration based on a two-step approach. The application of this method is straightforward for monostatic radar. The paper illustrates its extension to bistatic radar and analyzes the approximations when velocity varies vertically. Methods to handle vertical variations of the velocity and to control the aperture of the 3D operator are suggested.
6. Zanzi, L., 2010, Radar tomography for evaluation of reinforced concrete structures, in Non-destructive evaluation of reinforced concrete structures, Vol.2: Non-destructive testing methods, Maierhofer, C., Reinhardt, H.W., Dobmann, G., Eds., Woodhead Publishing Ltd., Cambridge, 334-369, ISBN 978-1-84569-950-5, doi: 10.1533/9781845699604.2.334.
Paper #6 is a state of the art illustration on the topic of radar tomography applied to concrete structures. Acquisition methods and processing algorithms are presented and a wide list of reference papers is offered to those interested in more in-depth studies. Resolutions, possible artifacts and criteria for interpreting the results are discussed to introduce the reader to a correct use of the technique.
7. Arosio, D., Munda, S., Zanzi, L., da Porto, F., Mosele, F., 2012, Non-destructive quality control of reinforced masonry buildings, ASCE Journal of Infrastructure Systems, 18, N.1, 34-46, ISSN 1076-0342, doi: 10.1061/(ASCE)IS.1943-555X.0000054.
Paper #7 shows the potential of GPR technique for detection and classification of possible defects in modern reinforced masonry structures. Experiments performed on laboratory specimens where different defects were simulated are illustrated and analyzed to demonstrate the feasibility of the method as a non-destructive quality control tool which might be applied on-site with real-time results.