寬頻分碼多工無線系統中上鏈碼同步在數位信號處理器之實現

Abstract

在傳送資料之前，直接序列展頻通訊技術必需要進行頻率、框(Frame)、碼(Code)之同步。在這篇論文中，對於碼同步在3GPP/UTRA FDD WCDMA標準中所提供的通道模型做了些討論。論文一開始先對一般現有的擷取(Acquisition)方式做個介紹，其中包括解展頻(Despreading)方式和非同調後偵測積分器(Post-detection integration)的架構。然後對於已經擷取到的信號路徑(Path)後續追蹤和搜尋未找到的信號路徑提出處理方法。在多通道的通訊模型中，信號路徑管理是個重要的課題。這篇論文對於這方面也有所探討。最後，以I.I. Quatro6x DSP板實現碼同步理論之即時運算。

Direct sequence spread spectrum technology requires frequency, frame, and code synchronization between the transmitter and receiver before transmitting information data. In this thesis, code synchronization in the multipath channels specified by 3GPP/UTRA FDD WCDMA standard is discussed. First, conventional acquisition methods are overviewed, including various despreading methods and post-detection integration (PDI) schemes. Then the methods of tracking the obtained paths and searching new paths that are not found by acquisition are proposed. In the multipath channel, the path management is an important issue. This thesis has a discussion about this issue. Finally, these synchronization algorithms are implemented in the I.I. Quatro6x DSP card to realize the real-time processing of code synchronization.