Ship-radiated Noise Reconstruction Using The Higher-order Spectrum

The sailing ship radiated noise transmission distance. Reconstruction of ship-radiated noise and its simulation technology is an important branch of the military objective characteristics and it is a hotspot and difficult area in the national and international research. As electronic countermeasures technology, the underwater targets in the laboratory of radiation noise, especially radiation noise simulation and reconstruction of vessels subject to a great deal of attention at home and abroad. Based on higher-order statistics theory, underwater targets in a wide frequency band noise reconstruction is realized. The main work and originality in this thesis can be summarized as follows:1.The ship-radiated noise is researched. Based on the mechanism of higher-order spectrum of the Gaussian process is not sensitive, we distill the Bispectrum and1(1/2) -spectrum characteristics of underwater radiated noise.2. Based on the Bispectrum reconstruction theory, we use least squares arithmetic set up a model of the signal amplitude and phase of the reconstruction. Signal analysis and simulation of the reconstruction algorithm verify the correctness. According to the bispectrum of underwater radiated noise characteristics, we achieve the objectives of the reconstruction of underwater radiated noise signal amplitude and phase. We use the amplitude and phase of the reconstruction resume the time-domain waveform of underwater radiated noise signal.3. Based on the 1(1/2)-spectrum reconstruction theory, we use DFT arithmetic set upa model of the signal amplitude and phase of the reconstruction. Signal analysis and simulation of the reconstruction algorithm verify the correctness. According to the1(1/2)-spectrum of underwater radiated noise characteristics, we achieve the objectives ofthe reconstruction of underwater radiated noise signal amplitude and phase. We use the amplitude and phase of the reconstruction resume the time-domain waveform of underwater radiated noise signal.4.We compared the two method of reconstruction. The effect of Bispectrumreconstruction method is better, and the method of 1(1/2) -spectrum reconstruction theoryis simple and easy to realize.5. Based on Bicep strum theory, we researched the ship radiated noise Bicep strum feature. The theory of ship radiated noise reconstruction by Bicep strum is established.