In this paper, we describe methods for computing fractionally spaced blind
equalizers directly from second-order statistics of the observations. The e
qualizers with all possible delays are computed simultaneously and the one
with the best delay is picked by a blind constant modulus index. Our algori
thm utilizes the equalizer output whitening property of the blind equalizer
s, i.e., output whitening yields equalization; thus, no channel identificat
ion is required. This may reduce the performance degradation that is caused
by channel estimation errors of channel estimation based approaches such a
s the subspace methods, In addition, existing channel output whitening-base
d approaches require nonlinear optimization and are unable to choose equali
zer delays, In contrast, our algorithm has simple closed-form solutions for
equalizers with all possible delays. Comparison of our algorithm with some
other algorithms in the similar category is given, which shows that our al
gorithm has more efficient computations. Simulations demonstrate the good p
erformance of our method.