Constant modulus algorithm is a most popular algorithm and is widely used for blind equalization of non-constant envelope signals and constant envelope signals. But it exhibits very slow convergence speed and large residual error. A modified variable step size algorithm is proposed based on constant modulus algorithm. Its theoretical analysis is made and it is simulated with binary sequence and quadrature amplitude modulation signals. Theoretical analysis and simulation results show that it has the characteristics of fast convergence speed and small residual error.
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