DS-CDMA系統(tǒng)中最大比合并的性能分析
Performance Analysis of Maximal Ratio Combining Diversity in DS-CDMA Systems
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摘要: 該文推導(dǎo)了存在信道估計誤差的DS-CDMA系統(tǒng)在多徑Rayleigh衰落信道中的誤碼率。數(shù)值計算結(jié)果表明當實際系統(tǒng)中的信道估計存在誤差并且信道多徑功率不等時，在假設(shè)相等噪聲功率和理想信道估計下得到的傳統(tǒng)最大比合并方法因無法輸出最大的信噪比而性能明顯下降。
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關(guān)鍵詞:
- 最大比合并; 誤碼率; 信道估計; 直擴碼分多址
Abstract: A new expression for the Bit Error Rate(BER) of a Direct-Sequence Code-Division Multiple-Access (DS-CDMA) system with non-ideal channel estimation in a frequency-selective Rayleigh fading channel is derived and evaluated. The analysis assumes an arbitrary number of independent, but non-identical resolvable paths combined by the conventional Maximal Ratio Combining(MRC) algorithm which is known to produce maxi-mal signal-to-noise ratio for diversity channels with equal noise powers and perfect channel estimates. The results obtained show that in such systems, the effects of non-identical fading and the channel estimation error on system performance cannot be ignored. -
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