臺灣博碩士論文加值系統

在本篇論文中，針對真實傳輸的封包傳送去模擬分析，在接收端訊號處理中的通道估計，提出一種演算法來改進得到的通道狀態資訊。Regularized LS估計法結合已知的領航訊號得到的通道資訊以及先前的通道資訊，來產生出比標準LS估計法來的還要準確的通道估計結果。
隨著傳輸的Symbol不斷的增加，利用Preamble產生較準確的通道資訊也會越來越少，所以在系統模擬時，當通道在時間上的相關性與 LS通道估計誤差在我們所提出的方法中為已知，就可以根據不同的SNR得到在真實傳輸驗證時，所需要得到的正規化參數。在根據驗證時當下的環境去給予最佳的正規化參數，來得到傳輸時給予系統較準確的通道估計，藉以提升系統效能。

In this thesis, for the real packet transmission to the simulation analysis, in the receiver signal processing channel estimation, proposed an algorithm to improve the channel status information. The Regularized LS estimation method combines the known channel information from pilot signal with the channel information and the previous channel information to produce an accurate channel estimation result than the standard LS estimation method.
However, with the continuous increase in the transmission symbol, the use of preamble to produce more accurate channel information will be less and less. In the system simulation, when the channel correlation in time and LS channel estimation error, we know in the proposed method, we can according to the different SNR in the real transmission verification, get the required normalization parameter. When the packet is delivered in real, the best regularization parameters are selected according to the current environment to obtain a more accurate channel estimate for the transmission to enhance the system performance.

目次
摘要 ----------------------------------------------------------------------------------------i
Abstract ii
目次 --------------------------------------------------------------------------------------iii
圖目次 -----------------------------------------------------------------------------------iv
表目次 -----------------------------------------------------------------------------------vi
第一章 簡介（前言、相關研究與研究動機、論文架構）---------------------1
第二章 OFDM系統的基本原理與架構 -------------------------------------------3
2.1. OFDM傳輸系統技術介紹與演進-----------------------------------------3
2.2. OFDM技術的系統架構-----------------------------------------------------5
2.2.1 位元映射（Mapping）轉換符元 ----------------------------6
2.2.2 離散時間之OFDM系統 --------------------------------------7
2.2.3 保護區間與循環字首 ------------------------------------------8
2.2.4 OFDM系統運作分析 -----------------------------------------11
2.3. OFDM模擬驗證系統之設計----------------------------------------------13
2.3.1 Transmitter -------------------------------------------------------------13
2.3.2 Channel -----------------------------------------------------------------15
2.3.3 Receiver ----------------------------------------------------------------15
2.4. OFDM系統之優勢與劣勢-------------------------------------------------18
第三章 領航訊號配置與通道估計 ------------------------------------------------19
3.1. 領航訊號的配置方法 -----------------------------------------------------20
3.1.1 Block-type--------------------------------------------------------------21
3.1.2 Comb-type -------------------------------------------------------------22
3.2. 最小平方(Least-Square, LS)誤差法--------------------------------------24
3.3. Regularized Least-Square通道估計---------------------------------------25
3.3.1 正定矩陣∑▒〖[n]〗---------------------------------------------------------26
第四章 數據分析與驗證結果--------------------------------------------------------28
4.1. LS與Regularized LS演算法之分析--------------------------------------28
4.2.正規化參數α(n)之分析與選用 --------------------------------------------39
第五章 結論------------------------------------------------------------------------------41
參考文獻 42

參考文獻
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