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An Algorithm for Variable Step-Size Improving Steady-State Performance of Blind Equalization  

Oh, Kil-Nam (광주대학교 광통신공학과)
Publication Information
The Journal of Korean Institute of Information Technology / v.9, no.10, 2011 , pp. 43-48 More about this Journal
Abstract
For blind equalization algorithms with excellent convergence characteristics, the steady-state performance is not the case. In this paper, for blind equalization, as a way to solve the problems of the methods commonly used to improve the steady-state performance, a scheme for variable step-size is proposed. In the proposed approach, as the equalizer converges to steady-state, the step-size is varied, and is decreased consistently as iteration proceeds in the steady-state. The proposed algorithm has improved the steady-state performance of the equalizer without compromising the initial convergence characteristics of the equalizer. The proposed method, applied to the algorithms with good blind convergence characteristics, is fit to improve the steady-state performance as well as making it easier to be combined with other algorithms by improving its steady-state performance. The proposed idea is applied to the constant modulus algorithm (CMA), then its performance improvement is confirmed under multipath propagation channel and higher-order QAM constellations.
Keywords
blind equalization; steady-state performance; variable step-size; CMA;
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Times Cited By KSCI : 1  (Citation Analysis)
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