摘要
超寬頻脈波電系統近年來在高速室內無線通訊應用之中頗受矚目，其應用領域包含家庭娛樂、無線影像下載、無線區域網路(wireless LAN)及無線USB等。由於該系統使用次奈秒(sub-nanasecond)週期之波形，其波形優良的時間解析(time-resolution)能力足以用於解出傳輸通道造成的多重路徑接收信號。然而為了要充分收集多重路徑中的傳送訊號能量，則必須使用具有高度硬體複雜度的犁耙式(Rake)接收器，使得接收機硬體設計因而複雜化。
為克服上述困難，有學者提出一種稱為參考傳輸(transmitted-reference, TR)的新型系統。由於參考信號構成發射信號的一部分，接收機可以很方便地利用這個已知的傳輸參考信號進行資料調變信號的解調，使得此系統之接收機無需進行複雜的傳輸通道估測工作，並得以大幅簡化其硬體設計。然而，原始參考傳輸架構的低複雜度偵測能力並非憑空獲致，由於參考信號並未承載任何資料位元，實際上會造成50%能量/頻寬的消耗。這項缺失已成為近年來研究改進超寬頻參考傳輸系統的熱門研究課題。
針對上述缺失，本論文提出一種足以增強性能表現的發射信號設計及接收信號架構，稱為雙平均N位元差分暨平衡參考傳輸系統(A2NDTR/BTR)。此新系統具有在維持整體系統性能表現條件下增進資料傳輸率的能力，此能力實際上是由整合新式的信號設計及偵測技術與其他優良之干擾及噪音壓制技術所共同達成。最後，電腦模擬顯示此新系統與其他系統相比較時，在維持相同或是較佳的位元錯誤率之下，同時能夠達成更高的資料傳輸率。

Abstract
Ultra-Wideband (UWB) impulse radio systems have gained much attention in high speed indoor wireless communications recently, their applications include home entertainment, wireless indoor downloading, wireless LAN, wireless USB, and so on. These systems apply sub-nanosecond pulses and are able to resolve the multipath caused by the communication channel due to their fine time-resolution capability. However, a Rake receiver with high hardware complexity is required to take full advantage of the available signal energy, which complicates the hardware design of the receiver.
To remedy this difficulty, an improved scheme called the transmitted reference (TR) systems is proposed. Since a reference signal is transmitted along with the data-modulated signal, this known signal can be conveniently used to demodulate the data-modulated signal in the receiver. Thus, TR systems do not require the complex task of channel estimation and render a simple receiver structure. However, the low-complexity detection in the conventional TR scheme is achieved at the cost of 50% energy/bandwidth disadvantage, due to the fact that the reference signal carries no data. This disadvantage has become the popular research focus of UWB TR systems.
In this dissertation a performance-enhanced signal and detection scheme, namely the dual averaging N-bit differential transmitted reference/balanced transmitted reference (A2NDTR/BTR) system, is proposed to increase the data rate while still maintain the overall system performance. Numerical results suggest that this proposed scheme is able to achieve superior data rate while maintain the same or better bit error performance as compared with others.

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