Stabilizing the fractionally spaced equalizer by prewhitening

A novel technique for stabilization of the adaptive fractionally spaced equalizer (FSE) is presented. The technique consists in whitening the signal at the FSE input, and in using the tap-leakage algorithm for adapting the FSE. The feature of the method is that, asymptotically, it achieves both optimal conditioning of the equalizer and no performance loss. A comparison with other stabilization techniques, namely the tap-leakage, the Uyematsu and Sakaniwa (1985) algorithm and an improved version of the latter algorithm, shows the effectiveness of our proposal