A combined LPC-based speech coder and filtered-X LMS algorithm for acoustic echo cancellation

• Published in: 2004 IEEE International Conference on Acoustics, Speech, and Signal Processing Vol. 4; p. iv
• Main Authors: Gordy, J.D., Goubran, R.A.
• Format: Conference Proceeding
• Language: English
• Published: Piscataway, N.J IEEE 2004
• Subjects: Applied sciences; Coding, codes; Convergence; Decoding; Decorrelation; Detection, estimation, filtering, equalization, prediction; Echo cancellers; Error correction; Exact sciences and technology; Filtering algorithms; Finite impulse response filter; Information, signal and communications theory; Least squares approximation; Miscellaneous; Signal and communications theory; Signal processing; Signal, noise; Speech processing; Speech synthesis; Telecommunications and information theory; Teleconferencing; Filtering; Acoustic signal; Input signal; Noise reduction; Tapping; Linear predictive coding; Acoustic signal processing; Echo suppression; Algorithm; Videoconference; Implementation; Digital filter; Acoustic noise; Vocal signal; Simulation; Signal processing; Finite impulse response filter; Decorrelation; Speech processing; Internet telephony; Least mean squares methods
• ISBN: 9780780384842; 0780384849
• ISSN: 1520-6149; 2379-190X
• DOI: 10.1109/ICASSP.2004.1326779

This paper presents a novel acoustic echo canceller structure based on combining the filtered-X LMS algorithm with an LPC-based speech coder for use in videoconferencing and VoIP. The algorithm updates coefficients using filtered versions of the input and error signals obtained by directly tapping the short-term excitation signal from the speech decoder, and by filtering the error signal with a bank of FIR decorrelation filters constructed from the LPC synthesis filter coefficients. The proposed algorithm was implemented using ITU G.729, and simulation results with 2000-tap room impulse responses show a faster and more constant rate of convergence than NLMS using speech input signals and an average 10 dB greater ERLE observed during convergence.