Anchored constant modulus algorithm (ACMA) for blind equalization

Blind equalization is a technique of adapting an equalizer without the need of a training sequence. The constant modulus algorithm (CMA) is one of the first known blind equalization algorithms. The cost function of the CMA exhibits local minima, which are the primary cause of the ill-convergence of the CMA. Anchoring the CMA improves the performance of the CMA in terms of ill-convergence. This technique is used with the linear and the decision feedback equalizers. It is shown that the adaptive equalizer will always remove intersymbol interference (ISI) as long as the channel gain exceeds a certain critical value