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| 研究生： |
李致寬 Lee, Chih-Kuan |
|---|---|
| 論文名稱： |
MIMO-OFDM系統在頻域及時域之通道估測 On the Frequency and Time Domain Channel Estimation for MIMO-OFDM Systems |
| 指導教授： |
張名先
Chang, Ming-Xian |
| 學位類別： |
碩士 Master |
| 系所名稱： |
電機資訊學院 - 電腦與通信工程研究所 Institute of Computer & Communication Engineering |
| 論文出版年： | 2009 |
| 畢業學年度： | 97 |
| 語文別： | 英文 |
| 論文頁數： | 45 |
| 中文關鍵詞： | 多重輸入輸出 、通道估測 、通道參數 、正交分頻多工 |
| 外文關鍵詞： | channel estimation, MIMO, OFDM, channel parameters |
| 相關次數： | 點閱：152 下載：0 |
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在MIMO-OFDM系統中，為了達到好的效能，在接收端我們需要正確的通道估測。在本篇論文中，我們首先比較時域及頻域之通道估測。對於頻域的通道估測法，LMMSE是能達到最理想效能之演算法，但其複雜度卻相當的高。對於時域的通道估測法，我們在未知的OFDM符號區塊之前傳送一根單位脈衝，而在接收端我們將可立即的得到時域通道響應。模擬結果顯示了時域估測演算法在相同的資料傳送率及引導信號能量(pilot signal energy)下，可達到較好的效能。
應用時域估測法，我們提出一個由時域通道為模型的頻率通道估測演算法。其模擬的結果顯示，我們所提出的演算法之均方誤差及錯誤率在高訊雜比時靠近LMMSE演算法。
For the multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system, the receiver needs accurate channel estimation to achieve good performance. In this thesis, we first compare the frequency domain and time domain channel estimation. For the frequency domain channel estimation, the linear minimum mean-squares error (LMMSE) algorithm can attain the optimal performance, but its complexity is quite high. For the time domain channel estimation, a unit pulse is put ahead every OFDM symbol block, and the receiver can readily obtain the time domain channel response. The simulation shows that the time domain algorithm attains better performance under the same data rate and pilot signal energy.
Implied by the time domain approach, we also propose a frequency domain channel estimation algorithm based on the time domain channel model and the least-squares fitting. The simulation shows that the proposed algorithm results mean-squares error (MSE) and bit-error rate (BER) near those of the LMMSE algorithm.
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校內：2059-07-15公開校外：2059-07-15公開