Based Line Train Noise Canceling Technology Research

Towed array sonar has serious radiated noise and self-noise, greatly affect the range of effective observation,limiting the far distance of detection. Noise cancellation is an urgent key technology in the signal processing of towed array sonar. The ship's noise cancellation technology is not mature in both theory and practical applications. Adaptive noise cancellation make the interference noise as the research object, in order to inhibit and attenuate the noise.As the complicated of underwater acoustic environment and experimental conditions,the adaptive noise cancellation technology is still in the laboratory research.In this paper, with the study of towed array sonar systems and the interference noise model, we have made several method of noise cancellation, finally, propose a new method,it's IBF-ANC(inverse beamforming-Adaptive Noise Cancellation).The main work and research are as follows:1 Based on the sea trial data, analyzed the noise's frequency and spatial characteristics. Especially the response phenomenon of the noise at the receiver array --- deviation from the theoretical value. Then established an acoustic field model, the same time combined the directivity of linear array and the frequency dispersion of shallow water and any other factors. Finally given a more reasonable explanation.In addition, here presents a simple and practical modeling and simulating method for towed ship radiated noise.2 As the towed ship radiated noise has a wide frequency band and multi-path propagation characteristics, Discuss several methods of noise cancellation:Postbeamformer Interference Canceller, Inverse Beamforming, Adaptive Beamforming, Delayed Transplacement Subtraction, and Adaptive Noise Cancelling.3 Combination with adaptive noise cancellation algorithm, a new method is proposed-IBF-ANC,this method could offset broadband noise,as well as enhance the target signal SNR, the sea trial data processing results verified that the method's performance.4 In this paper, based on the target detection and tracking processing system on signal processor platform. Adding the adaptive noise cancellation module to it, to achieve real-time adaptive noise cancellation in processing system.so the adaptive noise cancelling technology turn to application.