Network echo canceller based on the practical adaptive filter

In this paper, a new network echo canceller based on the practical adaptive filter is proposed. The proposed adaptive filter practically modifies the lattice transversal joint (LTJ) adaptive filter. It takes advantage of information in the speech decoder and coefficients of the transversal filter part in the LTJ adaptive filter are updated every other sample instead of every sample. Total complexity of the proposed adaptive filter is lower than that of the transversal filter. And the residual echo signal is decreased by residual echo cancellation using the lattice predictor whose order is less than 10. Computational complexity of the proposed echo canceller is lower than that of the transversal filter but the convergence speed is faster than that of the transversal filter. The performance of the proposed network echo canceller was verified by the experiments using the real speech signal.