The proportionate normalized least mean square (PNLMS) algorithm was developed for use in network echo cancelers. In comparison to the normalized least mean square (NLMS) algorithm, PNLMS has a very fast initial convergence and tracking when the echo path is sparse. Unfortunately, when the impulse response is dispersive, the PNLMS converges much slower than NLMS. This implies that the rule proposed in PNLMS is far from optimal. In many simulations, it seems that we fully benefit from PNLMS only when the impulse response is close to a delta function. We propose a new rule that is more reliable than the one used in PNLMS. Many simulations show that the new algorithm (improved PNLMS) performs better than NLMS and PNLMS, whatever the nature of the impulse response

Meeting Name

2002 IEEE International Conference on Acoustics, Speech, and Signal Processing, 2002. ICASSP '02


Electrical and Computer Engineering

Keywords and Phrases

NLMS Algorithm; PNLMS Algorithm; Adaptive Algorithms; Adaptive Filters; Adaptive Signal Processing; Convergence; Convergence of Numerical Methods; Delta Function; Digital Simulation; Echo Suppression; Filtering Theory; Impulse Response; Least Mean Squares Methods; Network Echo Cancelers; Normalized Least Mean Square Algorithm; Simulations; Telephone Networks; Tracking; Transient Response

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type





© 2002 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jan 2002