第四代行動通訊技術（4G）中，正交分頻多工（Orthogonal Frequency Division Multiplexing, OFDM）是主要的調變技術。OFDM利用多個相互正交的子載波來傳輸數據，從而提高了頻譜效率和抗干擾能力。然而這些子載波之間的正交性會因為通道特性和環境因素的影響而受到破壞，導致子載波間的旁帶（Side lobe）互相干擾，這些旁帶會對其他用戶的訊號造成干擾，增加錯誤率，從而影響訊號傳輸的可靠性和穩定性。為了解決上述問題，通用濾波正交分頻多工（Universal Filtered-Orthogonal Frequency Division Multiplexing, UF-OFDM）技術應運而生。UF-OFDM在每個用戶的傳輸信號上透過濾波器的作用來降低旁帶對其他用戶的影響。這種濾波方法有效地減少了由旁帶引起的干擾，從而在多用戶同時上傳的環境中提供了更好的訊號傳輸品質。
本論文中會提出一種新的同步估計方式，提升接收訊號同步準確度，降低錯誤率。所提出的方式改良於傳統Schmidl所提出將兩重複的前導碼(Preamble)做內找最大相關性方式，並且利用UF-OFDM需與filter摺積的特性額外增加了過filter後摺積所產生疊加訊號之可用Preamble與並且結合誤差正規化技術額外加入了重複Preamble之間誤差的資訊，使在做相關性的過程中有更多的資訊採納並且使的時間測量值(Timing metric)更加的收斂且準確，藉此改善了因傳統方式資訊不足而產生的平台效應(Plateau effect)，使同步Peak 點能找的更準確。

In the fourth generation of mobile communication technology (4G), Orthogonal Frequency Division Multiplexing (OFDM) is the primary modulation technique. OFDM utilizes multiple orthogonal subcarriers to transmit data, thereby enhancing spectral efficiency and interference resistance. However, the orthogonality among these subcarriers can be disrupted by channel characteristics and environmental factors, leading to inter-subcarrier side lobe interference. These side lobes can interfere with signals from other users, increase error rates, and affect the reliability and stability of signal transmission. To address these issues, Universal Filtered-Orthogonal Frequency Division Multiplexing (UF-OFDM) technology has emerged. UF-OFDM reduces the impact of side lobes on other users' signals by filtering each user's transmission signal. This filtering method effectively reduces interference caused by side lobes, thereby providing better signal transmission quality in multi-user simultaneous uplink scenarios.
In this paper, we propose a new synchronization estimation method that improves the accuracy of received signal synchronization and reduces error rates. The proposed method is an improvement over the traditional method introduced by Schmidl, which uses two repeated preambles to find the maximum correlation. Additionally, we exploit the characteristic of UF-OFDM that requires convolution with a filter, allowing for the use of overlapping signals generated after filtering with the preamble. By incorporating differential normalization technique, we also use information about the different between repeated preambles. This provides more information during the correlation process, making the timing metric more convergent and accurate. As a result, this approach mitigates the plateau effect caused by insufficient information in traditional methods, allowing for more accurate identification of the synchronization peak point.

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