Resource Allocation in Multi-Antenna MAC Networks: FBMC vs OFDM

This paper addresses the problem of resource allocation in a multiple access channel where several mobile terminals (MT's) are transmitting simultaneously to a single receiving base station, all of them with multiple antennas and exploiting beamforming. A multi-carrier modulation is assumed, either orthogonal frequency division multiplexing (OFDM) or filter bank multi-carrier (FBMC). The main advantage of FBMC is that the spectrum of the sub-channels is much more concentrated than for OFDM. This property is explicitly exploited in this paper in order to evaluate an asynchronous network where the transmissions from different MT's are not aligned in time. This implies that a frequency guard between groups of carriers assigned to different users has to be included, being larger for OFDM than for FBMC. The improvement in performance due to this fact is evaluated by means of the rate that can be achieved by dynamically allocating carriers to users and by calculating the power and bit loading to be applied.