BLIND FRACTIONALLY-SPACED EQUALIZATION OF NOISY FIR CHANNELS - DIRECTAND ADAPTIVE SOLUTIONS

Blind fractionally spaced equalizers reduce intersymbol interference u sing second-order statistics without the need for training sequences, Methods for finding FIR zero-forcing blind equalizers directly from th e observations are described, and adaptive versions are developed, In contrast, most current methods require channel estimation as a first s tep to estimating the equalizer, The direct methods can be zero-forcin g, minimum mean-square error, or even minimum mean square error (MMSE) within the class of zero-forcing equalizers, Performance of the propo sed methods and comparisons with existing approaches are shown for a v ariety of channels, including an empirically measured digital microwav e channel.