Nonlinear narrowband active noise control method based on Volterra filter

Abstract

The invention provides a nonlinear narrowband active noise control method based on a Volterra filter and aimed at a situation that higher harmonic noise is generated after a narrowband noise source is distorted nonlinearly. A linear signal synthesis subsystem (1), a nonlinear signal synthesis subsystem (2), a reference signal generation module and a least mean square algorithm module are used in the method; a reference signal in the method is generated by a synchronous signal generator based on a source noise frequency obtained by a non-acoustic sensor; one part of a secondary source is synthesized through a linear combiner, the other part of the secondary source is synthesized through another linear combiner and the nonlinear Volterra filter, and when primary source noise is distorted nonlinearly, a fundamental component and a higher harmonic component are independently inhibited by a linear filter and the nonlinear Volterra filter respectively. According to the nonlinear narrowband active noise control method, the nonlinearly distorted narrowband noise can be effectively inhibited, and the influence of nonlinearity on system performance can be easily analyzed due to an independent working structure.

Description

technical field [0001] The invention relates to a nonlinear narrow-band active noise control method based on a Volterra filter, belonging to the field of active noise control. Background technique [0002] Compared with traditional passive noise control, active noise control has good low-frequency performance and small control space, and has been widely used in the field of noise control. Among them, narrow-band active noise control is widely used. Narrow-band noise has regular low-frequency signal characteristics and is often generated by rotating equipment or devices with reciprocating motion. In narrow-band active noise control, the narrow-band noise frequency can be directly or indirectly measured by a non-acoustic sensor, and then a sine or cosine reference signal of the same frequency can be generated by a signal generator. [0003] In a linear or near-linear acoustic environment, linear narrowband active noise control can effectively deal with target noise. However,...

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Problems solved by technology

However, when the actual acoustic environment has a strong nonlinearity, the source noise propagates through the nonlinear channel and will produce serious nonlinear distortion or disturbance at the point of cancellation

At this point, linear narrowband active noise control systems will struggle to cope with

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