Sound intensity active acoustic shielding

Abstract

This invention discloses sound-intensity active sound screen including a passive sound screen, error mike flow array, secondary loudspeaker array and controller. In order to ensure noise-reducing effect, the error mike flow array should be arrayed at one side of observation spot and near the top of the passive sound screen. The distance between the error mike flow and the passive sound screen is obtained through defining and computing the coordinate of the secondary loudspeaker array and the sound screen. The sound intensity active sound screen has better noise-reducing effect than traditional active sound screen in low-frequency stage.

Description

1. Technical field [0001] The invention relates to a sound barrier, in particular to an active sound barrier. 2. Background technology [0002] To eliminate noise in a noisy environment and obtain a quiet area, the usual method is to use a sound barrier made of sound-insulating materials for noise reduction. However, the traditional sound barrier, that is, the passive sound barrier has certain limitations, and its noise reduction effect in the low frequency band is not good. Active noise control technology is mainly used in the low frequency range, and it is applied to passive sound barriers to become active sound barriers. The existing active sound barrier technology directly places the error microphone in the area that needs noise reduction, that is, the far field of the sound barrier, and controls the output of the secondary speaker array through the controller, so that the square of the sound pressure amplitude at the error microphone array and minimum, so as to achiev...

AI Technical Summary

Problems solved by technology

However, this method is not feasible in practical applications. For example, it is impossible to arrange many error microphones in the residential area next to the highway, and in this case, the distance between the error microphone and the secondary speaker is too large, and changes in the natural environment will cause Different effects on them will cause the noise reduction effect to be unstable

There are also active sound barrier technologies that use microphone arrays to pick up sound pressure signals in the near field of the sound barrier, and control the output of the secondary speaker array through the controller to minimize the sum of the squares of the sound pressure amplitudes in the near field of the sound barrier, thereby achieving far field noise reduction purposes, such as Figure 5 shown, but the noise reduction effect of this method is still not ideal

Images