Mf. Fahmy et al., SYSTEM-IDENTIFICATION USING DISCRETE ORTHOGONAL FUNCTIONS, International journal of circuit theory and applications, 21(4), 1993, pp. 317-329
In this paper a novel method is described for the design of adaptive I
IR filters used in system identification. The adaptive filter is imple
mented as a parallel connection of subsections whose transfer function
s constitute a set of discrete orthogonal systems. The adaptation algo
rithm used, which is of the Gauss-Newton type, adjusts the parameters
of these discrete orthogonal systems in order to match the desired out
put data of the unknown plant in a least squares sense. Owing to the o
rthogonality property, which ensures complete independence of subseque
nt sections, convergence is very rapid. Closed-form expressions for th
e gradient signals required to update the filter are given. Illustrati
ve examples have shown that this method always results in much improve
d adaptation properties compared with the already existing approaches.