Mean square error in an IIR adaptive echo canceller

An examination is made of the mean-square-error performance of an IIR (infinite impulse response) adaptive filter. The principal goal is to determine if IIR adaptive filters have an advantage over FIR (finite impulse response) adaptive filters in terms of either greater performance or less restrictive processing constraints. A stochastic analysis of the IIR algorithm, which results in a steady-state mean square error expression, is presented and that result is used as a tool to investigate performance in the echo canceller application. Simulations are used to verify the analytical result. The echo canceller study shows that the IIR algorithm offers approximately a 2:1 reduction in processing requirements compared to the FIR approach, without loss of performance