On the design of uplink and downlink group-orthogonal multicarrier wireless systems

Dept. of Math. & Inf., Univ. of the Balearic Islands (UIB), Palma de Mallorca
IEEE Transactions on Communications (Impact Factor: 1.75). 11/2008; DOI: 10.1109/TCOMM.2008.060497
Source: IEEE Xplore

ABSTRACT Group-orthogonal multicarrier code-division multiple access (GO-MC-CDMA) has been proposed as an attractive multiplexing technique for the uplink segment of wireless systems. More recently, a variant of this scheme has also been proposed for the downlink. This paper presents a unified bit error rate (BER) performance analysis of group-orthogonal wireless systems when using maximum likelihood (ML) multiuser/multisymbol detection covering both link directions. Valuable design rules regarding the number of subcarriers per group and the selection of spreading codes are derived. Simulations results using realistic system parameters and ETSI BRAN channel models are also presented which serve to validate the analytical results.

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