Mode Domain Spatial Active Noise Control Using Sparse Signal Representation
This addresses a practical bottleneck in implementing active noise control systems for large areas, offering an incremental improvement over existing techniques.
The paper tackles the problem of reducing the number of microphones needed for active noise control over large spaces by proposing a mode-domain feedforward method with sparse signal representation, achieving better noise attenuation with fewer reference microphones compared to conventional methods.
Active noise control (ANC) over a sizeable space requires a large number of reference and error microphones to satisfy the spatial Nyquist sampling criterion, which limits the feasibility of practical realization of such systems. This paper proposes a mode-domain feedforward ANC method to attenuate the noise field over a large space while reducing the number of microphones required. We adopt a sparse reference signal representation to precisely calculate the reference mode coefficients. The proposed system consists of circular reference and error microphone arrays, which capture the reference noise signal and residual error signal, respectively, and a circular loudspeaker array to drive the anti-noise signal. Experimental results indicate that above the spatial Nyquist frequency,our proposed method can perform well compared to a conventional methods. Moreover, the proposed method can even reduce the number of reference microphones while achieving better noise attenuation.