Steady-state and Tracking Analysis of Fractional Lower-order Constant Modulus Algorithm

摘要

The constant modulus algorithm based on fractional lower-order statistics (FLOS_CMA) has been proven to be an effective blind equalization method under α-stable noise. But there have been little results in the literature about the performance of this algorithm. In this paper, the steady-state mean-square error (MSE) performance of the FLOS_CMA is studied, and the approximate analytical expressions for real- and complex-valued data under stationary and non-stationary environments are derived, respectively, based on the energy-preserving relation and a Taylor series expansion. Based on the derived expression, an estimate for the FLOS_CMA step-size interval to ensure its convergence and stability is obtained, when it is initialized sufficiently close to the zero-forcing solution. Finally, simulation studies are undertaken to support the analysis.