Effect of secondary path lengths on the performance of FxLMS and virtual sensing technique based ANC system

Abstract

With the urbanization, exposure of mankind to the noise is increasing day by day leading to many health issues. For low-frequency noise reduction, active noise control system is widely applied in many applications. In the present paper, the effect of different secondary path lengths in FxLMS and virtual sensing technique based ANC system is studied. The virtual sensing technique based ANC is applied in the cases where it is not feasible to place the error microphone physically at the desired location. The filter coefficients of secondary path of ANC system are measured experimentally for the three different filter lengths, k (i.e., k = 64, 128, and 256) using Texas Instruments TMS320C6713 processor in the semi-anechoic chamber. The performance of ANC system with different filter lengths is analyzed in the terms of residual noise, signal-to-noise ratio, computational load, and error plots. The comparison suggests that secondary path of different filter lengths suits for FxLMS and virtual sensing technique based ANC systems.