The Local Minima of Fractionally-Spaced CMA Blind Equalizer
Cost Function in the presence of channel noise
Wonzoo Chung and J. Leblanc.
Abstract
We study the local minima relocation of the fractionally spaced
Constant Modulus Algorithm(FSE-CMA) cost function in the presence of
noise. Local minima move in a particular direction as the noise
power increases and their number may be eventually reduced. In such
cases the performance of FSE-CMA may fail to adequately reduce inter
symbol interference (ISI), but achieve an approximated MMSE by reducing
its equalizer noise gain under certain constraints.
We analyze the mechanism of relocation of FSE-CMA cost function local
minima in terms of the auto-correlation matrix of sub-channel convolution
matrix and its eigenvectors.
