An efficient adaptive cascade IIR filter

Adaptive cascade IIR (infinite impulse response) filters which have an easy stability check and low parameter sensitivities are studied. A novel concept is proposed which suggests backpropagating the desired signal through the inverse all-pole second-order sections and producing intermediate errors to be minimized. This concept is applied to a cascade IIR structure, resulting in an efficient adaptive cascade IIR filter. It is shown that the equation-error formulation is just a special case of backpropagation of the desired signal.<
>