Spatial scheduling algorithms for wireless systems

Real-time scheduling for wireless multiuser MISO systems under different fairness criteria

“…In the literature, two main techniques can be found for this difficult question: the maximum sum rate and the equal rate [4]. Besides, the definition of fairness is not clear.…”

“…In [3] the author solves this problem by a graph-theoretical technique, whereas in [4] we proposed the application of Simulated Annealing to this problem. However, this kind of techniques are too costly to be implemented in real-time, which is a mandatory requirement for a practical scheduling technique.…”

Practical bit loading schemes for multi-antenna multi-user wireless OFDM systems

“…After this procedure, each carrier is filled with a single user, and the AP shall fill the subcarriers until there are Q users preallocated per subcarrier. One could use rather cost-extensive approaches such as those developed in [5], but the scalar product is a good and very simple option. The procedure is summarized in Table I, and it is very intuitive.…”

“…As in other papers such as [5] or [13], we assume a ZF transmit beamforming, which is equivalent to the MMSE for a low number of users and also for high SNR [14]. Moreover, it provides a reasonable degradation with respect to the optimum sum capacity as shown in [15].…”

“…A well-suited beamforming criterion is Zero Forcing (ZF) [5], which provides a reasonable performance loss with respect to optimum downlink beamforming e.g. [6] or dirty paper precoding [7].…”