Narrow-band active noise reduction optimization system for in-vehicle engine order noise

Abstract

The invention discloses a narrow-band active noise reduction optimization system for in-vehicle engine order noise. The narrow-band active noise reduction optimization system aims at the situation that the engine rotating speed fluctuates in the actual driving process of an automobile. The method comprises the following steps: smoothing an acquired rotating speed signal through an exponential smoothing formula, constructing a more stable internal reference signal by utilizing the smoothed rotating speed signal, obtaining an output signal of a narrow-band active noise reduction system accordingto the internal reference signal, and then updating a weight coefficient of a filter so as to continuously update the output signal. According to the system, the problem that the noise reduction performance of the system is reduced due to the fact that internal reference signals show obvious unsteady-state characteristics caused by fluctuation of the rotating speed of an engine in actual conditions can be solved, and the system has popularization and application potential in the field of in-vehicle active noise reduction.

Description

technical field [0001] The invention relates to the technical field of active noise control in a vehicle, and more specifically, the invention relates to a narrow-band active noise reduction optimization system for engine order noise in a vehicle. Background technique [0002] Traditionally, the passive control of noise mainly reduces noise through three methods: controlling the noise source, cutting off the propagation path, and protecting the receiver. For low-frequency noise with longer wavelengths, thicker and heavier materials are required to achieve a good noise reduction effect, which means higher costs. Active Noise Control (ANC) technology uses the principle of sound wave interference to achieve noise reduction by rationally arranging microphones and secondary sound sources in the scene. Under the condition of the weight of the object, it is an efficient and cost-effective noise control method to effectively suppress its noise level and improve the sound quality of...

AI Technical Summary

Problems solved by technology

However, in actual situations, the working state of the engine is not absolutely stable. Even if the vehicle is running at a relatively stable and constant speed, the engine speed still fluctuates within a certain range, which will cause the constructed internal reference signal to have obvious unsteady characteristics. , which makes the convergence performance and noise reduction effect of the algorithm decrease

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