結合可變步階及可變長度適應性濾波器之演算法

The adaptive filter combined with variable step-size and variable tap-length

林繼駿(Chi-Chun Lin)

指導教授 ： 李仲溪

元智大學/電機通訊學院/電機工程學系/碩士(2012年)

https://doi.org/10.6838/YZU.2012.00270

摘要

適應性濾波器已經廣泛的被應用在訊號處理及通訊領域中，其中適當的步階常數以及合適的濾波器長度可使濾波器具有更優秀的能力。本論文提出一種結合可變步階及可變長度之適應性濾波器演算法；根據誤差訊號的函數迅速將濾波器長度追蹤至系統長度，降低濾波器的估測誤差，並結合不需參數設定的可變步階演算法，增加其收斂效能，使演算法能夠同時擁有快速的收斂速度與良好的穩態誤差。實驗模擬驗證我們提出的演算法的優秀效能。

關鍵字

適應性濾波器 ； 可變步階 ； 可變長度

並列摘要

Adaptive filters have been successfully applied to signal processing and digital communications. The suitable step-size and tap-length play critical roles of an adaptive filter. In this thesis, we propose an adaptive filtering algorithm combined with variable step-size and variable tap-length. The suitable tap-length is derived by using instant gradient estimates of error signal, and the resulting algorithm is capable of reducing errors and estimating the system length properly. The equipped variable step-size mechanism provides fast convergence rate and low steady-state mean squared errors as well. Effectiveness of the proposed algorithm is demonstrated through computer simulations.

並列關鍵字

Adaptive filter ； Variable step-size ； Variable tap-length

參考文獻

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