Frequency Domain Constant Modulus Algorithm Based on Fractionally Spaced Blind Equalizer

摘要

Aiming at the disadvantages of large mean square error(MSE) and slow convergence rate of Constant Modulus Algorithm(CMA), a frequency domain constant modulus algorithm based on fractionally spaced blind equalizer(FS FCMA) is proposed. In this proposed algorithm, fractionally spaced blind equalizer is used to avoid the spectrum aliasing caused by the sub-sampling and decrease the MSE effectively, and FFT technique and overlapping retention algorithm is employed for realizing the frequency domain constant modulus algorithm to improve the convergence performance of equalizer and to reduce the computational complexity greatly. The FS-FCMA has smaller MSE and faster convergence rate comparison with the constant modulus algorithm in time domain(TCMA) and constant modulus algorithm in time domain based on fractionally spaced blind equalizer(FS-TCMA). The good performance was simulated using underwater acoustic channel.