Informative Signal Analysis: Metrology of the Underwater Geomagnetic Singularities in Low-Density Ionic Solution (Sea Water)
- 1 DITEN-SEALab-ACM Laboratory, Department of Electric, Electronic, Telecommunication Engineering and Naval Architecture, University of Genoa, Genoa, Italy
- 2 Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy
- 3 CNR—Consiglio Nazionale delle Ricerche, ITD—Istituto per le Tecnologie Didattiche, Genoa, Italy
- 4 DITEN-SEALab-ACM Laboratory, Department of Electric, Electronic, Telecommunication Engineering and Naval Architecture, University of Genoa, Genoa, Italy
Abstract
The paper tackles the problem of reading singularities of the geomagnetic field in noisy underwater (UW) environments. In particular, we propose a novel metrological approach to measuring low-amplitude geomagnetic signals in hard noisy magnetic environments. This research action was launched to develop a detection system for enforcing the peripheral security of military bases (harbors/coasts and landbases) and for asymmetric warfare. The concept underlying this theory is the spatial stability in the temporal variations of the geomagnetic field in the observation area. The paper presents the development and deployment of a self-informed measurement system, in which the signal acquired from each sensor—observation node—is compared with the signal acquired by the adjacent ones. The effectiveness of this procedure relates to the inter-node (sensor-to-sensor) distance, L; this quantity should, on one hand, correlate the noise and, on the other hand, decorrelate the target signal. The paper presents the results obtained, that demonstrate the ability of self-informed systems to read weak magnetic signals even in the presence of very high noise in low-density ionic solutions ( i.e. sea water).
- Harris, F. (1978) On the Use of Windows for Harmonic Analysis with the Discrete Fourier Transform. Proceedings of IEEE, 66, 51-83. https://doi.org/10.1109/PROC.1978.10837
- Faggioni, O., Soldani, M., Leoncini, D.A., Crise, A., Grandinetti, P., Nasta, S. and Zunino, R. (2012) A New EMAG Metrological Approach for Submarine Detection: Fundamentals of the Numerical Protocols and Preliminary Field Performance. Proceedings of the 25th UDT Undersea Defence Technology Europe Conference, Ifa-Alicante, 29-31 May 2012, CD-ROM.
- Gabellone, A., Faggioni, O., Soldani, M. and Guerrini, P. (2007) C.A.I.Ma.N. Experiment. Proceedings of the 20th UDT Undersea Defence Technology Europe Conference, Naples, 5-7 June 2007, CD-ROM.
- Faggioni, O., Pinna, E., Savelli, C. and Schreider, A.A. (1995) Geomagnetism and Age Study of Tyrrhenian Seamounts. Geophysical Journal International, 123, 915-930. https://doi.org/10.1111/j.1365-246X.1995.tb06898.x
- Rikitake, T. (1958) Oscillations of a System of Disk Dynamos. Mathematical Proceedings of the Cambridge Philosophical Society, 54, 89-105. https://doi.org/10.1017/S0305004100033223
- De Vuyst, A. and De Meyer, F. (1973) Spectral Analysis of Geomagnetic Data from One Station (Dourbes 1960-1970). Institut Royal Meteorologique de Belgique, Publ., A, No. 80, 32.
- Menvielle, M. and Berthelier, A. (1991) The K-Derived Planetary Indices: Description and Availability. Reviews of Geophysics, 29, 415-432. https://doi.org/10.1029/91RG00994
- Faggioni, O., Soldani, M., Gabellone, A., Hollett, R.D. and Kessel, R.T. (2010) Undersea Harbour Defence: A New Choice in Magnetic Networks. Journal of Applied Geophysics, 72, 46-56. https://doi.org/10.1016/j.jappgeo.2010.07.001
- De Santis, A. (1993) Tempeste, Sottotempeste e baie magnetiche. Annali di Geofisica, 36, 55-77.
- NOAA, et al. (2010) NOAA Diving Manual: Diving for Science and Technology. 4th Edition Revised, Best Publishing Company, North Palm Beach.
- COMSUBIN (2011) Norme per le Immersioni. Marina Militare, Roma.
- Decherchi, S., Leoncini, D., Gastaldo, P., Zunino, R., Faggioni, O. and Soldani, M. (2011) Computational Intelligence Methods for Underwater Magnetic-Based Protection Systems. Proceedings of IJCNN International Joint Conference on Neural Networks, San Jose, 31 July-5 August 2011, CD-ROM.
- Leoncini, D., Decherchi, S., Faggioni, O., Gastaldo, P., Soldani, M. and Zunino, R. (2010) Linear SVM for Underwater Magnetic Signals Based Port Protection. Journal of Information Assurance and Security, 5, 401-408.