通道估計誤差對正交分頻多工系統在多路徑雷利緩慢衰落通道下之位元錯誤率之影響

Effects of Channel Estimation Error on the BER Performance of OFDM Systems in Multipath Rayleigh Slowly Fading Channels

黃俊富(Chun-Fu Huang)

指導教授 ： 易志孝

淡江大學/工學院/電機工程學系碩士班/碩士(2007年)

https://doi.org/10.6846/TKU.2007.00254

摘要

在本論文中，我們研究通道估計誤差對正交分頻多工系統在多路徑雷利緩慢衰落通道之下之位元錯誤率之影響。由於可加白色高斯雜訊和殘餘載波頻率偏差所引起的載波間干擾，使得基於訓練符號的通道估測不完美。我們使用基於BPSK、QPSK、16-QAM、64-QAM的調變系統下所推導出的位元錯誤率公式，來描述由不完美的通道狀態資訊所導致系統效能降低的特性。而我們所推導出來的位元錯誤率公式不需要複雜的積分計算，可以很容易的計算出結果並且相當的精確。電腦模擬的結果可以驗證我們的理論分析。

關鍵字

正交分頻多工 ； 符際干擾 ； 載波干擾 ； 可加高斯雜訊 ； 載波頻率偏差 ； 通道狀態資訊 ； 效能分析 ； 位元錯誤率

並列摘要

In this thesis, we study the effects of channel estimation error on the bit error probability of orthogonal frequency division multiplexing (OFDM) systems in multipath Rayleigh slowly fading channels. The channel estimation errors come from the additive white Gaussian noise (AWGN) and intercarrier interference (ICI) caused by the residual frequency offset (CFO) We derive the bit error rate (BER) formulas for BPSK, QPSK, 16-QAM, and64-QAM modulation schemes to characterize the performance degradation resulting from imperfect channel state information (CSI). Without complex numerical integrals in our BER formulas, they can be evaluated easily and accurately. Simulation results verify the correctness of our theoretical analysis.

並列關鍵字

orthogonal frequency division multiplexing ； intersymbol interference ； intercarrier interference ； additive Gaussian noise ； carrier frequency offset ； channel state information ； performance analysis ； bit error rate

參考文獻

[24] Ahmad R.S Bahai, Burtion R. Saltzberg and Mustafa Ergen , Multi-Carrier Digital Communications Theory and Applications of OFDM. New York: Springer Science+Business Media, 2004.

[2] J. K. Cavers, ”The performance of phased locked transparent tone in band with symmetric phase detection,” IEEE Trans. Commun., vol. 39, no. 9, pp. 1389-1399, Sep. 1991.

[3] J. K. Cavers, ”An analysis of pilot-symbol-assisted modulation for Rayleigh fading channels,” IEEE Trans. Veh. Technol., vol. 40, no. 5, pp. 1389-1399, Nov. 1991.

[4] L. Cao and N. C. Beaulieu, ”Exact error-rate analysis of diversity 16-QAM with channel estimation error,” IEEE Trans. Commun., vol. 52, no. 6, pp. 1019-1028, June 2004.

[6] Y. Li, L. J. Cimini, and N. R. Sollenberger, ”Robust Channel Estimation for OFDM Systems with Rapid Dispersive Fading Channels” IEEE Trans. Commun., vol. 46, no. 7, pp. 902-915, Jul. 1998.