Frequency adaptive active sound absorption system

Abstract

The invention provides a frequency adaptive active sound absorption system, which is characterized by comprising a program-controlled variable negative capacitance circuit, a piezoelectric plate, a signal conditioning circuit, a peak detection circuit, an automatic gain circuit, a sampling circuit and a single chip microcomputer. The program-controlled variable negative capacitance circuit is respectively connected with the single chip microcomputer and the piezoelectric plate, the piezoelectric plate is connected with the signal conditioning circuit, the signal conditioning circuit is connected with the peak detection circuit, the peak detection circuit is connected with the automatic gain circuit, the automatic gain circuit is connected with the sampling circuit, and the sampling circuit is connected with the single chip microcomputer. The frequency adaptive active sound absorption system provided by the invention has more excellent dynamic characteristics and a wider application range, has adaptive system characteristics, and can follow a changing target frequency.

Description

technical field [0001] The invention relates to the technical fields of acoustics, electronics and control, in particular to a frequency adaptive active sound absorption system. Background technique [0002] Sound absorption systems are widely used in daily life. Common application scenarios include reducing mechanical noise pollution, optimizing indoor sound field environment, and noise reduction in headphones. [0003] Sound absorption systems are generally divided into two types: passive and active. Passive sound absorption systems usually adjust the mechanical impedance of the system in the form of materials and systems to achieve sound absorption. A common practice is to use the natural frequency of the system to attenuate the sound. The sound absorption capacity provided by this method is limited. Once the material and system are fabricated and the mechanical impedance and natural frequency are determined, the sound absorption range is narrow and fixed. However, in ...

AI Technical Summary

Problems solved by technology

However, real-time calculation and response, involving signal processing algorithms, digital filtering, fast Fourier transform, etc., have great computational complexity and space complexity, and require high processors

And because it involves calculation and analysis, the active sound absorption system needs to overcome the influence of delay, making the system very complicated and not robust enough

Additional sensors make it costly and unsuitable for large areas

[0005] In view of the above-mentioned related technologies, the inventor believes that there are more complicated problems in the sound-absorbing system, therefore, it is necessary to propose a technical solution to improve the above-mentioned technical problems

Images