An enhanced Godard blind equalizer based on the analysis of transient phase

This paper proposes an enhanced version of Godard blind equalizer, also known as the constant modulus algorithm, with faster convergence speed. To show that the cause of slow convergence is closely related to the behaviour of equalizer output power, the difference between the behaviour of equalizer output power and the reduction of intersymbol interference is studied by comparing the two types of minimum points of constant modulus cost function. For faster convergence, we insert a gain stage after the equalizer to control the behaviour of equalizer output power. We show the effects of gain stage on the convergence speed through simulations. We also show that the proposed method can be applied for other algorithms based on the modulus, such as the multimodulus algorithm.

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