An Adaptive Widely Linear Per-Group Frequency-Domain Semiblind Multiuser Receiver

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Samphan Phrompichai
Peerapol Yuvapoositanon


In this paper, a widely-linear (WL) technique is applied into an adaptive per-group frequency-domain (PG-FD) semiblind multiuser equaliser. This algorithm is designed for space-frequency block code (SFBC) downlink multiple-input multiple-output (MIMO) multi-carrier code division multiple access (MC-CDMA) with common pilot channel (CPICH) systems and without cyclic-prefix (CP). The update algorithm relies on information from blind and non-blind parts, and the projection on the subspace spanned by the training and the desired user spreading codes matrices. Numerical results illustrate that the proposed adaptive WL PG-FD semiblind multiuser equaliser significantly outperforms and more robust than existing adaptive PG-FD semiblind multiuser and adaptive PG-FD training-based equalisers in fast time varying multipath 3GPP2 MIMO channel model with high mobility.

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