Variable-gradient method for adaptive equaliser

A simple technique for the implementation of an adaptive equaliser is a gradient-seeking method. Two critical parameters associated with adaptive equalisation are the rate of convergence and the steady-state mean-square error attainable. When a fixed gradient is used in the gradient-search procedure for an adaptive equaliser, rapid convergence and a small steady-state mean-square error are two conflicting requirements. Use of a variable gradient parameter at each iteration provides a good compromise. A method for iteratively computing the gradient parameter is introduced, so that the random walk in the gradient-search procedure is executed, on the average, with decreasing step size as the iterative algorithm converges.