福特拉判別式迴授等化器

Abstract

傳統判別式迴授等化器的優點是在設計和應用上很簡單,然而,其正向等化 器是個線性等化器,它在輸入訊號空間的判別區域被超平面( hyperplanes)所限制,因此限制了系統的性能。本文提出一種新的非線等 化器,稱為福特拉判別式迴授等化器,它形成非線性的判別界限,因此能有 效的克服傳統判別式迴授等化器的性能限制,尤其是當傳輸通道為非線性 時,更能顯出它的優異性能。再者,在訓練模式時 ,可以使用傳統的適應性 演繹法。模擬結果顯示是個有效設計。 The advantages of a conventional decision feedback equa- lizer(CDFE) is its simplicity in design and in implementa- tion. However, the feedback part of CDFE is a linear equa- lizer and, hence,the decision regions in the signal space are delimited by hyperplanes. This property limits the performance of the system. In the articles, we propose a new adaptive nonlinear equalizer, called Volterra-based decision feedback equalizer, which is capable of forming nonlinear decision boundaries in the signal space. As a result, the performance limit in the CDFE can effectively be overcome. Especially, it has outstanding performance whenever the transmission channel is nonlinear. Moreover, conventional adaptation algorithms can be directly applied to the new structure. The simulation result demonstrate that the new structure can be an effective alternative in contrast to the CDFE.