Tracking performance analysis of fractional lower order constant modulus algorithm

The fractional lower-order constant modulus algorithm (FLOS_CMA) has been proven to be an effective blind equalisation method under a-stable noise. But there have been few results in the literature about its performance. The tracking performance of the FLOS_CMA in non-stationary environments is studied. The approximate expression is derived based on the energy-preserving relation and Taylor series expansion. Based on the derived expression, an estimate is obtained for the FLOS_CMA step-size interval to ensure its convergence and stability, when it is initialised sufficiently close to the zero-forcing solution. Simulation studies have been undertaken to support the analysis.