標題: 改善相位同調盲蔽等化器收斂效果之研究
On Improving the Convergence Behavior of a Phase Coherent Blind Equalizer
作者: 陳正熙
Cheng-Hsi Chen
李大嵩
Ta-Sung Lee
電信工程研究所
關鍵字: 盲蔽等化器;相位同調;自我正交法;格狀濾波器;載波再生;blind equalizer; phase coherent; self orthogonalization; lattice filter; carrier recovery
公開日期: 1993
摘要: 在現代的無線通訊系統中,由於通訊環境相當複雜,造成多重路徑干擾的
現象,影響通訊的品質。為了提高通訊的效能,吾人常利用盲蔽等化器來
克服多重路徑干擾對系統的影響。在本論文中,吾人探討盲蔽等化方法的
收歛情形及其改良的方法。對於相位同調盲蔽等化方法,通道輸出訊號的
相關矩陣的特徵值分佈嚴重地遲緩了等化器的收歛速率。為了改善其效能
,吾人提出應用自我正交法及格狀濾波器來提高系統的收斂速率。此外,
為了克服非理想解調所引發的相位誤差對收歛速率的影響,吾人提出方法
來補償固定的相位誤差。吾人亦推導出配合相位同調盲蔽等化使用的載波
再生方法,以追蹤時變的相位擾動。最後,吾人以電腦模擬的結果來驗證
以上所提出的方法確實有效。
In this thesis, we discuss the convergence properties of a
previously developed blind equalization algorithm and propose
methods for improving its performance. In blind equalization,
the rate of convergence depends heavily on the eigenvalue
spread of the data correlation matrix. A natural way of
speeding up the convergence would then be to orthogonalize the
correlation structure, which may be achieved by applying the
self orthogonalizing algorithm and lattice filter structure.
On the other hand, in order to alleviate the effect of phase
errors on the convergence of the proposed equalizer, we
proposed supervised and unsupervised methods for detecting
fixed phase errors resulting from channel disturbance. We also
derived a carrier recovery algorithm for tracking time varying
phase jitters. The efficacy of the proposed methods are
demonstrated by simulation results.
URI: http://140.113.39.130/cdrfb3/record/nctu/#NT820436016
http://hdl.handle.net/11536/58143
Appears in Collections:Thesis