Research on The underwater vehicle radiated noise model and the linear spectrum extraction method
Underwater vehicle radiated noise is the sound source of target detection and tracking of navy weapons. With the development of combat simulation and virtual training, the underwater vehicle radiated noise signal model was applied widely. Meanwhile, with the improvement of underwater vehicle radiated noise controlling technology, it becomes more and more difficult in extracting the low frequency linear spectrum noise from the other noise since the former is easily submerged by the latter. In the paper, the formation mechanism of underwater vehicle radiated noise is studied, and continuous spectrum component with underwater vehicle acoustic property is simulated by FIR filter based on LMS algorithm firstly, and then the radiated noise is created by combining continuous spectrum component with the line-spectrum component. To increase the signal to noise ratio of linear spectrum and suppress the continuous spectrum component, the adaptive linear spectrum extraction method is proposed based on EMD interval-threshold de-noising technology, which overcomes the disadvantages of traditional spectrum analysis and the wavelet analysis. Finally, the simulation model of underwater vehicle radiated noise and low frequency linear spectrum component extraction method are validated via simulation test.