多輸入多輸出技術應用於多載波分碼多工系統之研究

The Research of MIMO Technique in MC-CDMA Systems

陳珮倫(Pei-Lun Chen)

指導教授 ： 呂振森

國立臺北科技大學/機電學院/電機工程系所/碩士(2005年)

摘要

本論文主要探討在多路徑緩慢衰落通道下，多輸入-多輸出技術應用於多載波分碼多工系統上，所能提供的效能改善。當多載波分碼多工系統的載波數目夠多時，通常可以將多路徑延遲通道視為平坦通道來分析與探討。多輸入-多輸出技術主要是在傳輸端與接收端架設多根天線，提供分集增益，以降低由無線通道所造成的訊號衰落的影響。本論文將分別使用單一使用者偵測器及最小均方誤差多使用者偵測器，比較此二偵測器在多輸入-多輸出以及傳統的單輸入-單輸出多載波分碼多工系統之效能。為得到可靠分析，除以理論推導單一使用者偵測器與多使用者偵測器的位元錯誤機率公式及其近似公式，並將理論值與上鍵通訊系統及下鍵通訊系統中電腦模擬所得的位元錯誤率做比較，提出可信的分析結果。

關鍵字

多輸入多輸出 ； 多載波分碼多工 ； 緩慢衰落 ； 平坦通道 ； 多使用者偵測

並列摘要

The goal of this thesis is to research into Multi-Input Multi-Output techniques for MC-CDMA system in multi-path slowly fading channels and to improve the performance of this system. Multi-path channels are usually assumed to be flat channels when the number of carriers is large enough in the MC-CDMA system. Multi-Input Multi-Output technique is set up by using several antennas individually at the transmitter and receiver. It can provide diversity gain and reduce signal fading caused by wireless channels. In this thesis, we use both single-user detector and MMSE multi-user detector to compare the performance of these detectors in Multi-Input Multi-Output MC-CDMA system with traditional Single-Input Single-Output MC-CDMA system. To provide a reliable performance analysis, we derive both the bit-error-rate formulas and their approximate versions, then verify these formulas with bit error rates simulated by computer in both up-link and down-link MC-CDMA systems.

並列關鍵字

Multi-Input Multi-Output ； MC-CDMA ； Slowly Fading ； Flat Channel ； Multi-user Detector

參考文獻

[1] A. J. Viterbi, CDMA-Principles of Spread Spectrum Communication, Addison- Wesley Wireless Communications, June 1995.

[3] S. Moshavi, “Multi-user detection for DS-CDMA communications,” IEEE Comm. Magazine, Vol. 34, No. 10, pp. 124 -136, Oct. 1996.

[4] S. Verdu, Multi-user Detection, Cambridge University Press, August 1998.

[6] J. A. C. Bingham, “Multi-carrier modulation for data transmission: An idea whose time has come,” IEEE Comm. Magazine, pp. 5-14, May 1990.

[8] J. K. Cavers, Mobile channel characteristics, Boston Kluwer, 2000.