In this paper,the method of using open loop transmit diversity in a multi user DS-CDMA system operating in a frequency selective fading environment is considered.A novel approach is proposed for linear multi user detection in conjunction with transmit diversity to combat channel fading,multi user interference and inter symbol interference.By assigning spreading codes,blind and semi blind algorithms are developed for channel estimation and detection.Simulation results demonstrate that the proposed tech nique offers substantial performance over the RAKE receiver based on space time block codes,especially in a near-far situation.
Key words
ransmit diversity /
multi-user detection /
space time coding /
CDMA receiver
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References
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Footnotes
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