利用正交調變架構實現可調的帶通濾波器

THE TUNABLE BANDPASS FILTER USING QUADRATURE MODULATION STRUCTURE

李佳峻(Jia-Jiun Li)

指導教授 ： 劉皆成

大同大學/電機資訊學院/通訊工程研究所/碩士(2008年)

摘要

這篇論文將介紹正交調變架構的一般應用，以及針對利用正交調變架構所產生的可調的帶 通濾波器來討論以及修改。使正交調變架構也能產生可調的FIR帶通濾波器。首先，我們先 提出利用正交調變架構所產生的可調的帶通濾波器在通帶上有交疊的缺點。以及假如基本 型濾波器是線性相位的FIR 濾波器，帶通響應的輸出未必仍然有線性相位的特性。因此我 們將正交調變架構上加入的參數，讓輸出的線性相位不會被破壞。最後，應用PI 的技術讓 可調的FIR 帶通濾波器可以減少許多硬體資源。也希望新的可調FIR 帶通濾波器能夠找到 更好的應用。

關鍵字

可調的帶通濾波器 ； 正交調變

並列摘要

In this thesis, we will introduce the application of generalized quadrature modulation structure. The focus is discussed and modified the tunable bandpass filter which is obtained by using the principles of quadrature modulation structure. The tunable finite-impulse response (FIR )bandpass filter can be obtained by using the principles of quadrature modulation structure.

First, we mention that tunable bandpass filter which is obtained by using the principles of quadrature modulation structure had overlap in pass band. If the prototype filter is a FIR filter with linear-phase characteristics, the resulting bandpass response will not have a linear-phase response. So we add parameter m to keep that tunable bandpass filter’s output have linear-phase characteristics.

Finally, the tunable FIR bandpass filters using pipelining/interleaving technique can greatly reduce hardware resource. And we expected to find better tunable FIR bandpass filter’s application in the future.

並列關鍵字

QUADRATURE MODULATION ； TUNABLE BANDPASS FILTER

參考文獻

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[4] G. J. Dolecek, “One approach to a modulation of a bandpass signal,” IEEE

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[6] Jiang Zhongnong and A. N. Jr. Willson, “A pipelined/interleaved IIR digital filter architecture,” IEEE Trans. Singal Processing, vol.3, pp. 2217-2220, April 1997.