Variable step-size based online acoustic feedback neutralization in single-channel active noise control systems

This paper concerns acoustic feedback neutralization (FBN) during online operation of single-channel active noise control (ANC) systems. In existing approach, two FIR filters are used for this task: adaptive for feedback path modeling (FBPM) and fixed for FBN. Previously, we have proposed a simplified method where these two tasks of modeling and neutralization have been combined into one feedback path modeling and neutralization (FBPMN) adaptive filter. Here we introduce an intuition based based variable step-size (VSS) parameter, for LMS equation of FBPMN filter. This VSS is motivated from the fact that the error signal of FBPMN filter contains a disturbance component that is decreasing in nature. The computer simulations are carried out which demonstrate that the proposed method achieves better performance than the existing methods and at somewhat reduced computational cost.