Blind Equalization with Adaptive Variable Step Sizes Based on Parallel Laguerre Filter
Received date: 2016-05-12
Revised date: 2016-11-14
Online published: 2017-03-30
A blind equalization algorithm with adaptive variable step sizes based on parallel Laguerre filter is proposed to overcome problems such as long tap coefficients, and high bit error rate (BER) caused by deep fading channels. By analyzing existing filter structures and blind equalization algorithms, the proposed algorithm replaces traditional tapped delay with Laguerre sequence to make tap coefficients shorter. Meanwhile, convergence is accelerated by using a decision-directed algorithm and a fractionally spaced structure. Since the step size has a great effect on convergence speed and residual error, different algorithms with variable step sizes are compared. Based on the comparison, a revised equalization algorithm structure is devised to achieve the most suitable step sizes for high-speed common data link (CDL). Compared with traditional blind equalization algorithms, experimental results show that the proposed method improves equalization performance and reduces BERs remarkably.
Key words： blind equalization; variable step size; common data link; Laguerre filter
CUI Lin, YANG Jun-an, WANG Wei, LIU Hui . Blind Equalization with Adaptive Variable Step Sizes Based on Parallel Laguerre Filter[J]. Journal of Applied Sciences, 2017 , 35(2) : 207 -216 . DOI: 10.3969/j.issn.0255-8297.2017.02.007
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