Differentiated multiuser resource allocation scheme for multi-band UWB systems

This paper considers the dynamic resource allocation in a multiuser context taking into account the quality of service (QoS) requirements for the high-rate ultra-wideband (UWB) systems. The aim of this paper is twofold. First, we exploit the effective SINR method in the multi-band WiMedia solution proposed for UWB systems. This method is based on the exploitation of the characteristics of multiple sub-carrier SINRs in order to provide the channel state information needed for the multiuser sub-band allocation. Second, using the effective SINR as a channel metric, we derive a multiuser convex optimization problem to find the optimal allocation for all users while differentiating between two traffic classes: hard-QoS and soft-QoS. A low-complexity cross-layer allocation algorithm is also proposed. The cross-layer solution is a combination of two simple processes, one working at the PHY level and the other at the MAC level. Simulation results show that the proposed cross-layer solution performance is close to that of the optimal solution and it outperforms the single-user WiMedia solution in the hard-QoS users case.