跳到主要內容

臺灣博碩士論文加值系統

(44.211.117.197) 您好!臺灣時間:2024/05/27 04:57
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:范俊杰
研究生(外文):Fan, Chun-Chieh
論文名稱:直接序列展頻通訊系統中幾項同步技術之研究
論文名稱(外文):The Study of Several Synchronization Techniques in Direct Sequence Spread Spectrum Communication Systems
指導教授:蔡志宏蔡志宏引用關係---
指導教授(外文):Zsehong Tsai
學位類別:博士
校院名稱:國立臺灣大學
系所名稱:電機工程學系研究所
學門:工程學門
學類:電資工程學類
論文種類:學術論文
論文出版年:1998
畢業學年度:86
語文別:中文
論文頁數:126
中文關鍵詞:展頻碼同步擷取追蹤匹配濾波器相關器
外文關鍵詞:Spread Spectrumcode synchronizationacquisitiontrackingmatched filtercorrelator
相關次數:
  • 被引用被引用:0
  • 點閱點閱:231
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:0
展頻(spread spectrum)技術在無線通訊(wireless communication)技術中,目前已
扮演極其重要之角色。而展頻通訊系統,在通訊傳輸的過程中,首先要考慮的是碼同步(
code synchronization),本論文即是著重在碼同步之研究。通常PN碼的同步可分為兩個
過程;第一個過程是擷取(acquisition),第二個過程是追蹤(tracking)。本論文中
,有兩個章節在討論擷取接收器,兩個章節在討論追蹤接收器。在第二章中,我們利用並
行匹配濾波器(matched filter)及預設資料位元變遷(presumed data bit transition
),提出一個並行搜尋的擷取結構來改善具有資料調變(data modulation)之PN碼的擷
取。第三章中,我們利用差異同調(differentially coherent)技術,提出一個架構簡
單的差異同調擷取接收器,在AWGN的環境下分析,若將此所提接收器,應用在測距(rang
ing)上,則與傳統之非同調平方律接收器(noncoherent square-law receiver)具有相
近之性能。第四章亦是利用差異同調技術,設計出一個差異同調延遲鎖住迴路(Differen
tially Coherent Delay-Locked Loop,DCDLL),此追蹤接收器,僅用一個相關器(corre
lator),因此結構簡單,而且避開了增益不平衡(gain-imbalance)的問題。在AWGN的
環境分析下,此接收器適合應用在測距上,並較僅用一個相關器之Tau- 抖動迴路(Tau-D
ither Loop,TDL)有較好之性能,在第五章中,我們將所提差異同調追蹤器,在快速雷烈
衰頹(fast Rayleigh fading)通道下分析,發現其不敏感於快速雷烈衰頹效應,在測距
的應用上,性能亦較TDL來得好。
Spread spectrum techniques have been rapidly developed and used in many commun
ication systems in the recent past. Due to the diverse types of channel envir
onments, the study of new techniques for coping with various wireless communic
ation issues have been intensive for years. Among many issues being studied so
far, synchronization playsan essential role in establishing reliable communic
ation systems. Usually, in direct sequence spread spectrum, the process of cod
e synchronization is performed in twosteps: code acquisition and then code tra
cking. And both are essential parts for designing code synchronization scheme.
In our thesis, there are two chaptersin discussing acquisition receivers and
two chapters in discussing tracking receivers. In Chapter 2, based on a PN ac
quisition receiver with parallel I-Q matched filter and presumed data bit tran
sition, we employ the parallelsearch strategy to improve acquisition process f
or PN sequence under data modulation. In Chapter 3,by employing the property o
f shift-and-add of PN code, we propose a differentially coherent acquisition s
cheme that has a simple structure similar to noncoherent square-law receiver.
In Chapter 4, a novel differen tially coherent delay-locked loop (DCDLL) for a
ccuratecode tracking is proposed for direct sequence spread spectrum systems.
Due to the use of the differentialdecoder and exactly one correlator, the pro
posed scheme avoids the problems of gain imbalance. The tracking errorvariance
and mean time to lose lock (MTLL) are derived by linear and nonlinear ana
lysis. W hen the proposed DCDLL scheme is considered to be applied in ranging,
the performance of the proposed DCDLL scheme is better than that of tau-dithe
r loop(TDL) in the AWGN environment.In Chapter 5, we consider the effect of ve
ry fast Rayleigh fading on the proposed DCDLL. The derived results provide a t
ool to determine the design parameters in the tracking system.
封面
目錄
第一章 緒論
第二章 具並行匹配濾波器之並行搜尋擷取接收器
第三章 差異同調擷取接收器
第四章 差異同調追蹤接收器在白色高斯雜訊下之分析
第五章 差異同調追蹤接收器在快速雷烈衰頹通道下之分析
第六章 結論與未來研究方向
英文附本
QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top
無相關期刊