隨著無線數據通訊的需求，無線區域網路(Wireless Local Area Network; 簡稱
WLAN)，無線都會網路(Wireless Metropolitan Area Network; 簡稱WMAN)以及無線個
人網路(Wireless Personal Area Network; 簡稱WPAN)已被廣泛地開發並應用在系統平台
上。針對此三種無線網路，相關的標準也在近期被提出，其中主要包括了IEEE 802.11n(因
應WLAN)，IEEE 802.11e/m(因應WMAN)以及IEEE 802.15.3a/c(因應WPAN)。在上述
三種網路系統的實體層設計裡， 正交分頻多工(Orthogonal Frequency Division
Multiplexing; 簡稱OFDM)是其主要的核心技術，而傅立葉轉換(Fast Fourier Transform;
簡稱FFT)器則是OFDM 系統所需用的關鍵性零組件。
從系統整合的觀點來看，為了可彈性地根據速度需求與所處環境來進行無線數據的
擷取，一個擁有多模式(Multimode)傅立葉轉換器的三重無線個人/區域/都會網路系統是
具有開發上的實用性。因此在本篇論文中，我們以傅立葉轉換硬體的兩種主要方案，即
管線式(pipelined)和基於記憶體式(memory-based)的架構為基礎，提出適用於三重無線個
人/區域/都會網路應用的多模式傅立葉轉換器設計。在管線式傅立葉轉換器的架構上，我們首先針對無線個人網路應用，以多路徑延遲
迴授(multipath delay feedback; 簡稱MDF)結構作基礎，提出一個具有高輸出入率
(throughput rate)之2048 點的傅立葉轉換器。藉由所提出之新穎的乘法化簡以及多路徑
數值縮放(multidata scaling)方法，我們可在所呈現的架構中改善硬體效能。此外，為了
進一步達到記憶體相關的節能，我們也在本篇論文中提到混合式記憶體擷取調度
(mixed-memory-access-scheduling; MMAS)的方案。針對多模式運作的需求，我們也進階
提出了一個靈活基數組態(flexible-radix-configuration; FRC)的MDF 架構。該架構能針對
無線個人/區域/都會網路的應用，以有效益的硬體方式來執行相關的高輸出入率和可變
點數並多重串數的傅立葉轉換運算。基於所提出的FRCMDF 結構，一個雙重最佳化
(dual-optimized)的乘法方案也被陳明以進一步改善面積與功率的效益。此外，我們所提
出的組態方式可針對跨模式下的功率可延展性(power scalability)提供了架構性的支援。
除了根源於MDF 架構的作法，基於記憶體式(memory-based)的傅立葉轉換器架構
也同樣被考量來針對無線區域網路，無線都會網路以及超寬頻(Ultra Wideband; UWB；
即WPAN 系統的早期規格)的應用作多模式傅立葉轉換器的開發。在本篇論文中，我們
亦提出一個基於記憶體式之多模式快速傅立葉處理器。該處理器可藉由新穎的記憶體配
置方法連同一個節能的多模式傅立葉轉換核心，來有效率地執行無線區域/都會/超寬頻
網路相關的傅立葉轉換運算。

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