Proportionate Adaptive Sub-Filters for Nonlinear Acoustic Echo Cancellation

The electronic components such as loudspeaker and amplifier in hand-free devices will add the nonlinear distortion (ND) into the echo path of the stereophonic acoustic systems. The stereophonic acoustic echo cancellation (SAEC) algorithms developed to minimize the effect of acoustic echo in these systems assuming linear echo path will suffer from degraded performance in presence of ND. However, no solutions were proposed to address issue of ND in SAEC. This paper introduces a sub-filter based NAEC framework for faster convergence and enhanced steady-state performance. The proposed framework employs the functional link approach in modeling the ND and focuses on improving the rate of convergence of NAEC for better echo cancellation performance. Simulations indicate that the proposed NAEC outperforms the variants of functional link based NAEC in terms of echo return loss enhancement for speech and colored noise inputs.