Asymptotic analysis of stabilisation technique for the blind fractionally spaced equaliser

The authors propose a technique to counteract the ill-conditioning of the blind fractionally spaced equaliser. The technique involves whitening the signal at the equaliser input and introducing a leakage term in the cost function minimised by the equaliser. The result is that, when applied to the Godard quartic cost function and to the infinitely long equaliser, such a technique yields optimal equalisation and actually counteracts the ill-conditioning