Tap-length Optimization of Decision Feedback Equalizer Using Genetic Algorithm

유전자 알고리즘을 이용한 결정 궤환 등화기의 탭 길이 최적화

  • Received : 2015.04.23
  • Accepted : 2015.05.29
  • Published : 2015.08.31


In the underwater acoustic communication channels, multipath reflection become the cause of obstacle. Generally, equalizer has been applied to overcome these problems. In this paper, the method was proposed to optimize tap-length of decision feedback equalizer using genetic algorithm. After inputting feed-forward filter length and feed-back filter length as genetic information of the genetic algorithm, it optimize tap-length using BER(bit error rate) calculation in accordance with object function. The object function consist of decision feedback equalizer and BER calculation. For the purpose of BER calculation in the object function, the method was proposed to optimize the tap-length of decision feedback equalizer with genetic algorithm using preamble signals. As a result of experiments, the optimized BER is 0.0355 for signals which were received through a 25m receiver and which were applied to calculate BER merely using preamble signals in object function. When all data were used to calculate BER in object function, the optimized BER is 0.0215.


Decision Feedback Equalizer;Genetic Algorithm;Optimization;Underwater Acoustic Communication


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