Abstract

The signal feature of propeller cavitation noise during acceleration or deceleration procedure can be used to passively detect and classify moving vessels and underwater vehicles in the port regions. By analyzing the chirp periodicity of the variation of propeller wake velocity under acceleration situation, this paper presents the time domain expression of the modulation envelope signal of the accelerating propeller noise, treating the signal as a Gaussian-shaped chirp periodic pulse train with increasing trend and fluctuating pulse amplitude. The paper investigates the characteristics of simplified fractional Fourier transform (SFRFT) spectrum of the chirp periodic signal, and thus obtains the relation between the chirp periodic signal and its chirp harmonics under the conditions of underwater passive detection. Furthermore, the experimental data of the cavitation tunnel satisfy the results obtained by simulation, which verifies the correctness of the proposed signal model.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.