A New Approach for Selective Multi-User Diversity in Nakagami Fading Channels

In this paper, a variation of the Selective Multi-User Diversity (SMUD) scheme is proposed in order to increase the spectral efficiency of a system and at the same time reduce the feedback load. For this purpose, we invoke some recent results in level crossing theory for non-Gaussian processes (particularly Nakagami processes) to take into account the Non-Fade-Duration of the users that are above of a pre-established threshold. We notice that the original SMUD scheme can be viewed as a particular case of this modification. We show that considering two threshold levels and the level crossing duration distribution of each user, we can improve the spectral efficiency about 5% and reduce the feedback load in almost 10% in comparison with the original SMUD.