Modified LMS and NLMS algorithms with a new variable step size

In this paper, the modified LMS and NLMS algorithms with variable step-size are presented. It is shown that the variable step size is computed using a ratio of the sums of weighted energy of the output error with two exponential factors α and β, thus the fast error convergence of the modified LMS and NLMS algorithms can then be achieved. Also, by properly choosing the values of α and β, the misadjustment can be further improved. A few simulation results are presented in support of the good performance of the proposed algorithms by comparing with other LMS-type algorithms. © 2006 IEEE.