The compensated filtered-X algorithm for active noise control system in duct

This paper presents the compensated filtered-X approach for active noise control (ANC) system in duct and illustrates the effectiveness by experiments with a fixed-point DSP processor. The proposed method can overcome the influence of time delay, which arise from the analog devices in ANC system, and help to improve the ability of noise reduction. In the meanwhile, the quantization and round off errors of fixed-point DSP can be also compensated. Experiments are demonstrated in a polyvinyl chloride (PVC) material circular duct. The ANC experiments demonstrated that the reduction of broadband noise with the compensated method is about 20 dB and about 45 dB for narrowband noise.