MU-MIMO in 4G Systems
This paper first presents an overview of the different MU-MIMO schemes included/being studied in 3GPP standardization; from LTE to LTE-Advanced. Various receiver architectures are then studied and their performance assessed through link-level simulations. Appealing performance increase offered by interference aware receiver is notably emphasized. Furthermore, system level simulations for LTE Release 8 are provided. Interestingly, it is shown that MU-MIMO only offers marginal performance gains with respect to single-user MIMO. This arises from the limited MU-MIMO features included in Release 8 and calls for improved schemes for the upcoming releases.