Unbiased equation-error adaptive IIR filtering based on monic normalization

We present a novel way to remove the bias in equation-error based adaptive infinite impulse response (IIR) filtering by conceiving a scheme called mon ic normalization. It is found that normalizing all the coefficients of the denominator filter by the first coefficient after each adaptation removes t he bias and leads to unbiased estimates. The analysis of stationary points is presented to show that the proposed method can indeed produce unbiased p arameter estimates in the presence of noise. The computer simulation result s also demonstrate that the proposed method performs better than or compara ble to existing algorithms, while requiring much lower computational comple xity.