关键词: 自适应均衡器, 最小误比特率准则, 分数阶长算法, 误比特率

Abstract: A variable tap-length adaptive equalizer based on the Minimum Bit Error Rate（MBER）?approach is proposed，named FT-MBER algorithm. Variable tap-length equalization is important to the problem of unknown multipath channel equalization. Accurate optimum tap-length estimation of the adaptive equalizer can complete the low complexity and good performance of the adaptive algorithm，but the Bit Error Rate（BER） performance of traditional equalizers based on Minimum Mean Square Error（MMSE） criterion isn’t ideal. FT-MBER algorithm takes the difference of the BER between adaptive equalizers with different tap-lengths as a factor to adjust the pseudo fractional tap-length，and only if the pseudo fractional tap-length is bigger than the threshold value，the tap-length is updated. Simulation results show the BER performance of FT-MBER algorithm is much better than traditional equalizers，can successfully track and estimate the optimum tap-length.

Key words: adaptive equalizer, minimum bit error rate criterion, fractional tap-length algorithm, bit error rate