超寬頻系統(Ultra Wideband System, UWB System)的特色是將訊號於極大的頻寬下進行傳輸。此特性能讓整個系統在使用低功率下，就有極高的資料傳輸速率。此外，超寬頻系統也提供了其他好處，例如能與其他系統共存於相同頻帶，極佳的時間解析度，和有效對抗多重路徑通道的信號衰退。
然而，因為超寬頻通道模型的分析不易，在先前的相關研究中大多使用簡化的通道模型，或是在通道模型的分析上以電腦模擬取代。此外，先前的研究裡多半假設符號區間夠大，以忽略符際干擾(Intersymbol Interference, ISI)所帶來的影響。但是這樣的假設和需求更高的傳輸速率是互相衝突的。
在本論文中，我們將在IEEE 802.15.3a的超寬頻通道模型下精確分析差動傳送參考(Differential Transmitted-Reference, DTR)系統的訊號干擾雜訊比(Signal-to-Interference-Plus-Noise Ratio, SINR)，並且考慮符際干擾所造成的影響。根據這些的精確分析，我們將探討在不同符號區間下得到最高的信號干擾雜訊比所需要的最理想積分時間。我們將發現這些最理想積分時間有一些特別的現象，而這些現象是在考慮符際干擾後才會出現的。基於這些特別的現象，我們提出了一個通用的積分規則。這個積分規則相當的簡單。而且利用這個規則，我們可以使系統得到趨近最理想的訊號干擾雜訊比。相較於先前的研究，我們提供了一個更加有效率，並且有深刻見解的方法來進行接收端的分析與最佳化。

The UWB system is a promising technology that can provide high-data rate and robustness to multipath fading. However, because of the difficulty in analyzing the UWB channel models adopted by the IEEE UWB 802.15.3a Task Group, previous analytical works regarding transmitted-reference systems are based on simplified channel models or computer simulations. Besides, the symbol duration is assumed to be sufficiently large so that the effect of intersymbol interference (ISI) can be ignored.

In this thesis, the exact evaluation of the signal-to-interference-plus-noise ratio for differential transmitted-reference systems over the IEEE 802.15.3a channel structure is derived regarding the effect of ISI. A simplified formula is also provided for ease of the following system analysis. In particular, the optimal integration time for different symbol durations and channel models is studied. Some special phenomena due to ISI and a universal rule to approach the maximum SINR can hence be characterized. Compared with the previous methodology, our analytical results provide a more efficient and insightful way to receiver design and optimization.

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