Application of an improved spherical omnidirectional loudspeaker array model in environmental noise pollution control

Area of Science:

• Acoustics
• Signal Processing
• Environmental Engineering

Background:

• Environmental noise pollution control is challenging, especially for mobile targets, due to limitations of traditional fixed systems.
• Existing noise reduction methods struggle with dynamic environments and limited coverage.
• There is a need for adaptive and mobile noise control solutions.

Purpose of the Study:

• To propose an innovative method for spatial target tracking and noise control using spherical omnidirectional loudspeaker arrays.
• To develop a system capable of dynamic noise reduction for moving targets.
• To achieve full-space coverage for noise reduction in dynamic environments.

Main Methods:

• Constructing a precise model of spherical omnidirectional loudspeaker arrays for sound wave propagation.
• Developing a spatial latitude and longitude mapping model for real-time target perception.
• Employing adaptive loudspeaker node selection and online secondary path modeling with auxiliary noise to create a quiet zone.
• Implementing a control system for dynamic noise reduction that moves with the target.

Main Results:

• The system successfully achieves dynamic tracking and visual management of slow-moving targets.
• During slow target movement (300-700 Hz), noise reduction is approximately 7.6 dB due to system update delays.
• When the target is stationary, the average noise reduction within the quiet zone reaches 17.8 dB.

Conclusions:

• The proposed system offers a viable solution for dynamic noise control of mobile targets.
• The system demonstrates effectiveness in creating adaptive quiet zones for noise reduction.
• Further improvements in filter coefficient updates could enhance noise reduction during target movement.