Title :
OFDM and DS-CDMA approaches, analysis of performances on fading multipath channels
Author :
Hicheri, Nizar ; Terré, Michel ; Fino, Bernard
Author_Institution :
Conservatoire Nat. des Arts et Metiers, Paris, France
Abstract :
We show how orthogonality constraints for DS-CDMA 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 DS-CDMA 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.
Keywords :
3G mobile communication; OFDM modulation; channel estimation; code division multiple access; fading channels; least mean squares methods; multipath channels; multiuser channels; radio links; sequences; spread spectrum communication; DS-CDMA spreading sequences; MMSE optimal despreading; OFDM sequences; UMTS downlink transmission; channel estimation uncertainty; cyclic prefix solution; fading multipath channels; orthogonality constraints; perfect channel estimation; simulations; spreading sequences; 3G mobile communication; Channel estimation; Downlink; Fading; Multiaccess communication; Multicarrier code division multiple access; Multipath channels; OFDM; Performance analysis; Uncertainty;
Conference_Titel :
Personal, Indoor and Mobile Radio Communications, 2002. The 13th IEEE International Symposium on
Print_ISBN :
0-7803-7589-0
DOI :
10.1109/PIMRC.2002.1045428