Design and Simulation of Variable Step-size Adaptive Equalization Algorithm

The effect of step-size factor on the performance of adaptive equalization algorithm is researched in the paper.If the step-size factor is big,convergence rate and track rate of the algorithm are faster,but state residual error is bigger after convergence.By contrast,if the step-size factor is small,convergence rate and track rate of the algorithm is slow,but state residual error is smaller after convergence.Therefore,the demand for step-size is contrary between convergence rate and convergence precision if the fix step-size is adopted.The Sigmoid function of mean square error and non-linear function of error signal are adopted as step-size control factor,and several algorithms are got.Simulation results show that convergence rate of the improved algorithm is quickened and state residual error is diminished.