Variable modulus mechanism for performing equalization without a priori knowledge of modulation type or constellation order

Abstract

A system, method and memory medium for performing blind equalization. A block {u} of the baseband samples is received. A function J of a vector f is minimized to determine a minimizer f. The function J depends on vector f according to J(f)=Σ(|y|−γ). The summation Σ corresponds to a sequence {y} of equalized samples. The sequence {y} of equalized samples is related to the block {u} according to a convolution relation {y}={u}*f. Parameter γ is a current modulus value. The current modulus value γ is updated to equal a ratio of a fourth moment of the sequence {y} to a second moment of the sequence {y}. The minimization and parameter update operations are repeated for a series of received blocks of baseband samples. The minimizer ffrom a last of the repetitions is used to determine final equalized samples.