A nonlinear acoustic echo cancellation scheme implementation using the blackfin microcomputer

Nonlinearity of amplifiers produces nonlinear echo in acoustic systems, which degrades the performance of audio communication. The paper presents an acoustic cancellation scheme that involve the least mean square (LMS) algorithm to update the parameters of the nonlinear function and the variable step size NLMS (VSS-NLMS) algorithm to determine the coefficient vector of the FIR filter. The performance analysis and the real time implementation using a digital signal processor (DSP) microcomputer (Blackfin BF533, form Analog Devices) are illustrated.