An evolutionary search algorithm for adaptive IIR equalizer

This paper investigates the channel equalization by using a recursive lattice filter cascaded with a sigmoidal activation function. A new evolutionary search algorithm is proposed for the adaptation of the equalizer coefficients. The new algorithm is based on random evolution of the filter coefficients during the adaptation phase of the gradient lattice algorithm. The proposed method can greatly improve the convergence speed of the gradient method and provide global search capability so as to give lower error performance. In addition, the new algorithm maintains the essence and simplicity of the original gradient descent method. The equalizer together with the new algorithm is shown to have lower bit error rate