A new approach to the design of complex all-pass IIR digital filters (Q5906630)

This paper introduces a least-squares approach for designing the phase of complex IIR all-pass filters which can be used to equalize nonlinear phase systems. The authors say that the algorithm converges very rapidly and the obtained IIR filters are stable: however the convergence of the proposed method and the stability of the designed filters are not proven. Some examples are given.