Variable Step Length Best Combination AEC Algorithm in IPC

Based on the echo interference in audio transmission of Network Camera (IPC), this paper presents Variable Step Length Best Combination acoustic echo cancellation (AEC) algorithm .It adjusts the convergence speed of variance by changing the step of the adaptive filter , in accordance with the best ratio combination of NLMS algorithm and RLS algorithm, to achieve faster convergence speed and good steady state characteristics of a short delay. Simulation and measurement under the network environment show that, the residual echo signal is more than 30dB lower than the far-end signal, delays 25ms below the steady-state characteristics.