LTE-A ( Long Term Evolution-Advanced ) 系統下行採用 OFDMA系統，使用主要同步訊 號( primary synchronization signal )和次要同步訊號 和次要同步訊號 ( second synchronization signal )來進行同步 ( synchronization )和扇面搜尋 ( sector search )/蜂巢搜尋 (cell search)，其中，主要同步訊號在 ，其中主要同步訊號在 LTE-A中採取 Zadoff-Chu序列進行同步。然而 Zadoff-Chu序列在時間延遲和頻率偏移存下， 序列在時間延遲和頻率偏移存下， 會產生極大的旁辦 ( side-lobe )，造成其同步性能不佳，故在本篇論文中挑選數 ，造成其同步性能不佳故在本篇論文中挑選數 個序列 如 CCK(Complementary Code Keying)、格雷互補碼 、格雷互補碼 (Golay Complementary Sequence)、Frank、最 大長度序列 (Maximum Length Sequence)與之比較並研究序列特性。本篇論文在扇面搜尋過程 與之比較並研究序列特性。本篇論文在扇面搜尋過程 進行以下步驟 :第一步，將訊框延遲半個做自相關找出時序 (frame timing)，第二步， ， 第二步將此訊框做小數點頻率估測，第三步利用同號來偵區段 (sector)和整數頻率偏移，最 後一步，則可確認扇面。 本篇論文在 Rayleigh環境 下討論序列特性，利用匹配濾波器來確認區段和蜂巢身分並 下討論序列特性，利用匹配濾波器來確認區段和蜂巢身分並 和原本的 Zadoff-Chu序;LTE-A (Long Term Evolution-Advanced) downlink uses OFDMA. This system uses the primary synchronization signal (P-SCH) and second synchronization signal (S-SCH) for synchronization and sector search/cell search. Among them, P-SCH uses Zadoff-Chu sequence to complete the synchronization work in LTE-A. However, Zadoff-Chu sequence will generate very large side-lobe and it will let its synchronization efficacy become worse if there exists time delay and frequency offset. Hence in this thesis, we pick several sequence for example, CCK, Golay Complementary Sequence, Frank and m-sequence to compare each other to discuss their sequence properties. Sector search in this paper contains following steps: First, using the delay frame to auto-correlate and to find the frame timing. Next, using this frame to do fraction frequency offset estimation. Third, using synchronization signal to estimate the sector and integer frequency offset. And in the end, we can confirm the sector. In this thesis, we discuss the sequence properties in Rayleigh channel. Use matched filter to confirm sector and cell identities, and we compare with Zadoff-Chu sequence in original system. Find out the sequence with better performance.
