CN-121999751-A - Space orientation active noise reduction system and method

CN121999751ACN 121999751 ACN121999751 ACN 121999751ACN-121999751-A

Abstract

The invention provides a space orientation active noise reduction system and a space orientation active noise reduction method, which comprise a signal input module, a signal processing module and a signal output module, wherein the signal input module comprises a reference microphone for collecting target noise signals and an error microphone for collecting residual noise signals, the signal processing module comprises an analog-to-digital converter, a DSP digital signal processor, a digital-to-analog converter and a power amplifier, the DSP digital signal processor processes the input target noise signals and the residual noise signals based on an adaptive filtering algorithm to generate secondary noise control signals, the signal output module comprises a secondary loudspeaker for emitting secondary sound waves, the reference microphone, the error microphone and the secondary loudspeaker are arranged along the same straight line direction, and the secondary sound waves propagate along the straight line direction and destructively interfere with the target noise to realize noise reduction. The method is particularly suitable for application scenes with definite noise source directions, and can realize effective noise reduction in a larger space range with fewer hardware resources.

Inventors

LIU ZHIEN
LI XINYI
CHEN WAN
Wu Zhanshuo
YU XINPING
HU MIAORAN
LUO YUTONG
YAN YINGJIE
ZHOU XINGCHI

Assignees

武汉理工大学

Dates

Publication Date: 20260508
Application Date: 20260205

Claims (10)

1. The space orientation active noise reduction system is characterized by comprising a signal input module, a signal processing module and a signal output module; The signal input module comprises a reference microphone for collecting a target noise signal and an error microphone for collecting a residual noise signal; the signal processing module comprises an analog-to-digital converter, a DSP digital signal processor, a digital-to-analog converter and a power amplifier; the DSP digital signal processor processes the input target noise signal and the residual noise signal based on an adaptive filtering algorithm to generate a secondary noise control signal; the signal output module comprises a secondary loudspeaker for emitting secondary sound waves; the reference microphone, the error microphone and the secondary speaker are arranged in the same straight line direction, and the secondary sound wave propagates in the straight line direction and destructively interferes with the target noise to realize noise reduction.
2. The spatially directed active noise reduction system of claim 1 wherein the signal input module further comprises a movable error microphone, wherein the movable error microphone is electrically connected to the DSP digital signal processor through a flexible cable, and wherein residual noise signals collected by the movable error microphone are converted by the analog-to-digital converter and then input to the DSP digital signal processor.
3. A spatially directed active noise reduction system according to claim 1, wherein a secondary speaker and a reference microphone are arranged in the same linear direction, the error microphone being located between the reference microphone and the secondary speaker.
4. A spatially directed active noise reduction system according to claim 1 wherein the direction of sound emission of the secondary speaker is the same as the direction of sound propagation of the noise source.
5. The spatially directed active noise reduction system of claim 1 wherein the signal processing module further comprises a filter that filters the signals collected by the reference microphone and the error microphone.
6. The spatially directed active noise reduction system of claim 1 wherein the DSP digital signal processor employs an ADSP-21489 chip, and wherein the signal processing module further comprises an audio interface chip and an I2S serial interface that are configured with the ADSP-21489 chip.
7. The spatially directed active noise reduction system of claim 1 wherein the reference microphone and the error microphone each employ a MAX9814 audio automatic gain control module, and wherein the MAX9814 audio automatic gain control module has an input sound pressure level in the range of 35dB to 86dB.
8. The spatially directed active noise reduction system of claim 1 wherein the adaptive filtering algorithm is a filtered least mean square algorithm.
9. A spatially-directed active noise reduction method, applicable to a spatially-directed active noise reduction system according to any one of claims 1 to 8, comprising the steps of: s1, collecting a target noise signal through a reference microphone and collecting a residual noise signal through an error microphone; s2, converting the target noise signal and the residual noise signal into digital signals through an analog-to-digital converter and inputting the digital signals into a DSP digital signal processor; step S3, the DSP digital signal processor processes the digital signal based on an adaptive filtering algorithm to generate a secondary noise control signal; S4, converting the secondary noise control signal into an analog signal through a digital-to-analog converter, amplifying the analog signal through a power amplifier, and outputting the analog signal to a secondary loudspeaker; And S5, the secondary loudspeaker emits secondary sound waves, the secondary sound waves and target noise are subjected to destructive interference to achieve noise reduction, wherein the reference microphone, the error microphone and the secondary loudspeaker are arranged in the same straight line direction, and the secondary sound waves propagate in the straight line direction.
10. The method of claim 9, wherein in step S2, the target noise signal and the residual noise signal are filtered by a filter and amplified by a power amplifier before being converted by the input analog-to-digital converter.

Description

Space orientation active noise reduction system and method Technical Field The invention relates to the technical field of noise control, in particular to a space orientation active noise reduction system and a method. Background Noise pollution has become one of the important environmental problems facing modern society. The traditional passive noise reduction technology mainly reduces noise through sound absorption materials and sound insulation structures, and the method has good effect on high-frequency noise, but has limited control capability on low-frequency noise, and often requires larger space and higher cost. In contrast, the active noise control (Active Noise Control, ANC for short) technology emits sound waves with the same amplitude and opposite phase to the noise to be controlled through a loudspeaker, and utilizes the destructive interference principle of the sound waves to realize active cancellation of the noise, so that the active noise control technology has remarkable advantages in the aspect of low-frequency noise control. However, the existing active noise reduction system still has a plurality of limitations in practical application. First, conventional systems tend to seek full spatial noise reduction, which results in a system requiring multiple microphone and speaker arrays to be configured, not only increasing hardware costs and system complexity, but also making it difficult to achieve the desired noise reduction in open space. Secondly, the existing system is large in size and complex in structure, is difficult to flexibly deploy and move, and cannot meet noise reduction requirements of users in different scenes. Again, most active noise reduction systems are designed for specific application scenarios, with poor scenario adaptability, and it is difficult to obtain good noise reduction effects in various scenarios such as factory workshops, medical environments, vehicles, residential living areas, and the like. Therefore, an active noise reduction technical scheme with simple structure, moderate cost, convenient deployment and good scene adaptability is urgently needed to meet the requirements of directional noise control in practical application. Disclosure of Invention In order to solve the technical problems, the invention provides a space orientation active noise reduction system and a space orientation active noise reduction method, which realize high-efficiency noise reduction in a specific direction through a linear array arrangement mode and have the advantages of simple system structure, convenience in integration, strong scene adaptability and the like. In order to achieve the above purpose, the invention adopts the following technical scheme: a space orientation active noise reduction system comprises a signal input module, a signal processing module and a signal output module; The signal input module comprises a reference microphone for collecting a target noise signal and an error microphone for collecting a residual noise signal; the signal processing module comprises an analog-to-digital converter, a DSP digital signal processor, a digital-to-analog converter and a power amplifier; the DSP digital signal processor processes the input target noise signal and the residual noise signal based on an adaptive filtering algorithm to generate a secondary noise control signal; the signal output module comprises a secondary loudspeaker for emitting secondary sound waves; the reference microphone, the error microphone and the secondary speaker are arranged in the same straight line direction, and the secondary sound wave propagates in the straight line direction and destructively interferes with the target noise to realize noise reduction. Preferably, the signal input module further comprises a movable error microphone, the movable error microphone is electrically connected with the DSP digital signal processor through a telescopic cable, and a residual noise signal collected by the movable error microphone is input into the DSP digital signal processor after being converted by the analog-to-digital converter. Preferably, a secondary speaker and a reference microphone are arranged in the same straight line direction, and the error microphone is positioned between the reference microphone and the secondary speaker. Preferably, the sound wave emission direction of the secondary speaker is the same as the sound wave propagation direction of the noise source. Preferably, the signal processing module further includes a filter, and the filter performs filtering processing on signals collected by the reference microphone and the error microphone. Preferably, the DSP digital signal processor adopts an ADSP-21489 chip, and the signal processing module further comprises an audio interface chip and an I2S serial interface matched with the ADSP-21489 chip. Preferably, the reference microphone and the error microphone each employ a MAX9814 audio automatic gain control module, and the in