Improved Convergence of Gradient Algorithms for Adaptive Iir Filters
نویسندگان
چکیده
The introduction of a simple correction term in gradient algorithms for adaptive IIR filtering is shown to improve their convergence and robustness. The error surface, i.e., the mean squared value of the output error as a function of adaptive coefficients, is quadratic in adaptive FIR filtering and thus a simple gradient search works well. This is not the case in adaptive IIR filtering where the error surface is far from being quadratic. Nevertheless, a simple modification of the updating equation of lattice-form algorithms can reduce this problem thus obtaining faster adaptive IIR filters.
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