Fixed-point Haar-wavelet-based echo canceller

Telephone line echo path impulse responses have been estimated using a Haar-wavelet-based adaptive filter. Estimation error of two percent has been tolerated. This has allowed structural simplification to the Haar-wavelet-based adaptive filter. Adaptive filter coefficients are then updated by using a wavelet-based LMS algorithm, modified for fixed-point arithmetic. The fixed-point wavelet echo canceller has been tested for white noise and colored noise input signals and has been compared with the fixed-point FIR echo canceller through simulations. The wavelet based canceller converges much faster than its FIR counterpart.