In order to extract feature of ship signal more effectively, we propose a new approach for mathematical morphological filtering based on the morphological features. Mathematical morphological filter is a new nonlinear filter, which can effectively extract the edge contour and shape characteristics. The stimulation signal is processed by mathematical morphological filtering of different structure elements, which confirms the effect of morphological filtering on suppressing noise and preserving the nonlinear characteristics. Using flat structure element, the measured ship-radiated noise signals are processed by average filter, and the filtered signals are analyzed on the frequency spectrum. Compared with other filters, the result shows that the mathematical morphological filtering can successfully extract the effective information from the ship-radiated noise signals.
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