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研究生: 李界鋒
Jei-Feng Li
論文名稱: 在寬頻分碼多重擷取技術上分配及再分配多重正交可變展頻係數碼
Multi-OVSF Code Assignment and Reassignment in WCDMA
指導教授: 許健平
Jang-Ping Sheu
口試委員:
學位類別: 碩士
Master
系所名稱: 資訊電機學院 - 資訊工程學系
Department of Computer Science & Information Engineering
畢業學年度: 89
語文別: 中文
論文頁數: 89
中文關鍵詞: 正交可變展頻係數碼寬頻分碼多重擷取技術分配及再分配
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  • 在3GPP技術標準上, 在OVSF編碼被用來區分不同的連線. 使用OVSF編碼可以提供可變的傳輸速率以彈性的因應不同頻寬需求的應用. OVSF編碼的分配跟在分配可以在系統的效能上扮演一個重要的角色. 假設只有一個碼可以分配給使用者可能會造成內部的浪費問題然而分配多重碼給使用者會增加系統的複雜度. 這篇文章最主要的目的是想提供更多使用者跟降低系統負載下找出好的碼的分配跟再分配的方法. 我們提出了四個分配跟再分配的方法: random, leftmost, crowded-first, and mostuser-first. 而模擬程式所呈現的結果crowded-first 跟 mostuser-first 比其他方法有更好的效果.


    1 Introduction 1 2 Background knowledge 3 2.1 OVSF Code Tree ............................... 3 2.2 Code blocking . . ............................... 4 2.3 Internal fragmentation . ........................... 5 3 Multi-code assignment 8 3.1 Code placement scheme ........................... 8 3.2 Code replacement scheme . . . . . . .................... 10 4 Simulation Results 15 5 Conclusion

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