OFDM and DS-CDMA approaches, analysis of performances on fading multipath channels
نویسندگان
چکیده
In this paper we show how orthogonality constraints for DSCDMA spreading sequences yield directly to OFDM sequences. Having shown this duality we do a comparison of performances between these two waveforms in a multipath fading channel context. The comparison includes the MC-CDMA approach. We show how the cyclic prefix solution can be used for DSCDMA in order to propose an MMSE optimal despreading solution. This first part of our study is based on a perfect channel estimation. The second part includes channel estimation uncertainty in the comparison. Parameters of simulations, presented in this paper, correspond typically to an UMTS downlink transmission.
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