Dual Mode Blind Equalization Algorithm Based on Adaptive Switching
ZENG Leya① XU Hua① WANG Tianrui②
①(Information and Navigation College, Air Force Engineering University, Xi’an 710077, China) ②(School of Geography Science, Nanjing Normal University, Nanjing 210046, China)
The constant modulus algorithm is widely used in the blind equalization of wireless communication system, in order to reduce further the steady-state error, it is usually combined with the decision directed least mean square algorithm. The traditional dual mode blind equalization algorithm can achieve the hard switching of the two algorithms by setting the threshold value artificially. The rationality of the switch can not be guaranteed, it also can not fully highlight the advantages of dual mode switching. In this paper, the structure of the convex combination is used to achieve the switching between two modes and can adaptively choose the switching time. It improves the convergence rate and reduces the steady-state error by modifying the algorithm and normalizing the mixed parameter. In addition, the steady-state performance is derived and analyzed. Simulation results demonstrate that the performance of the model is consistent with the results, the effect of parameter normalization is obvious. Compared with other similar dual mode switching algorithms, it has better performance.
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