適用於 IEEE 802.11n 環境之 Alamouti 空時碼傳輸模式的模擬與分析

Computer Simulation in the IEEE 802.11n Environment of Alamouti Space Time Coded Transmission Mode

涂善博(SHAN-BO TU)

指導教授 ： 劉宗憲

國立中正大學/工學院/通訊工程學系/碩士(2016年)

摘要

混合式 (Hybrid) Alamouti STBC (space time block coded, 空時區塊編碼) 系統
結合了 SDM (spatial division multiplexing, 空間分集多工) 與 Alamouti STBC 這兩
種技術,能改善 MIMO (multi-input multi-output, 多重輸入與多重輸出) 系統的傳輸錯誤率因而獲得更可靠的傳送品質。論文中根據 IEEE 802.11n amendment 5 之規格,以 4-by-4 MIMO-OFDM 系統為例,針對 MIMO-OFDM 接收機中頻率偏移估計、時間同步、通道估計以及解調這幾個區塊來做討論。空時碼解調的部份則使用ZF(zero- forcing) 、MMSE (minimum mean square error) 、QR-SIC (QR-successive interference cancellation) 三種不同的演算法。設計出適用於 IEEE 802.11n 環境搭配 GUI(graphical user interface, 圖形化輔助使用者操作介面) 介面的 Matlab 模擬程式,藉由此程式來模擬分析 MIMO-OFDM 系統結合混合式 (hybrid) Alamouti STBC 後的系統位元錯誤率 (bit error rate,BER) 與傳統使用 SDM 模式時的系統位元錯誤率來做比較。

關鍵字

正交分頻多工系統 ； 多重輸入多重輸出 ； 空時區塊碼

並列摘要

Hybrid Alamouti space time block code (STBC) system combines the spatial division multiplexing (SDM) with Alamouti STBC. The combination of these two technologies can improve transmission quality for the multiple input multiple output with orthogonal frequency division multiplexing (MIMO-OFDM) system. In this thesis, the baseband receiver of 4-by-4 STBC-MIMO-OFDM system that satisfies the IEEE 802.11n standard is realized. The receiver includes functional blocks of frequency offset estimation, time synchronization, channel estimation, and detection. Especially, three STBC detection algorithms, including the zero- forcing (ZF), minimum mean square error (MMSE), QR-successive interference cancellation (QR-SIC), are realized. These realized algorithmsare integrated into a graphical user interface (GUI) program written in Matlab simulation tool. Finally, plenty simulation results, obtained by extensively running this GUI program, are reported for the BER comparisons of SDM and STBC detection techniques.

並列關鍵字

MIMO-OFDM ； Alamouti ； STBC ； SDM

參考文獻

[1] IEEE Std 802.11n,Standard for Information technology-Telecommunications and information exchange between systems-Local and metropolitan area networks-

Specific requirements-Part 11: Wireless LAN Medium Access Control (MAC)

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