Ship noise power spectrum analysis circuit and method based on controllable filter bank

Abstract

The invention discloses a ship noise power spectrum analysis circuit and method based on a controllable filter group, which effectively improves the fineness and real-time performance of signal power spectrum analysis. The technical scheme of the present invention is: a ship noise power spectrum analysis circuit based on a controllable filter bank, which is characterized in that it includes a series of filters set in parallel on the frequency band where the ship noise energy is concentrated and the series connection of the square integral detector combination, and a digital signal processor, wherein the outputs of all square-sigma detectors are connected to the inputs of the digital signal processor. The passband and center frequency of each channel filter are controlled by the external clock frequency, and each frequency band of ship radiation noise can be scanned sequentially according to the preset order, because the ship radiation noise signal power spectrum has certain time stability.

Description

technical field [0001] The invention belongs to the technical field of ship noise analysis, in particular to a ship noise power spectrum analysis circuit based on a controllable filter bank and a method thereof. Background technique [0002] The ship radiated noise power spectrum generally consists of two components. One is broadband noise, which mainly comes from the cavitation process of seawater near the propeller, and the frequency extends continuously from near zero to tens of kilohertz; the other is an extremely narrow line spectrum, mainly concentrated below 1 kilohertz. low frequency band. In the power spectrum analysis of ship radiated noise signals, the line spectrum is especially valued, which is mainly caused by the reciprocating motion of the ship's mechanical parts, the periodic water hammering of the propeller blades and the blade resonance. Not only the concentrated and stable energy unique to the ship radiated noise power spectrum can be used to improve de...

AI Technical Summary

Problems solved by technology

[0003] The conventional power spectrum analysis method of ship radiated noise based on digital filter banks involves large-scale numerical calculations and has high requirements for digital circuit hardware platforms, and the real-time performance of calculation results is limited by the computing speed of hardware platforms; Although the analog filter method has better real-time response, it is limited by the scale of the system circuit. The number of narrow-band filters is limited after all, and the dense arrangement of filter banks directly limits the precision of signal power spectrum analysis.

Therefore, for small self-sustaining systems that have requirements for various indicators such as circuit scale and power consumption, the current conventional, purely digital or analog filter banks are used to analyze the power spectrum of ship radiated noise, and it is difficult to take into account the analysis results real-time and precision

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