A Cross-Layer Design for Downlink Scheduling in SDMA Packet Access Networks

This paper deals with the problem of downlink scheduling in SDMA packet access networks. The performance of the SDMA system is predominantly affected by the mutual interference between users. In order to ensure the quality of service (QoS) and enhance the resource utilization, the scheduler needs to jointly consider the constraints from the physical layer (spatial separability for instance) and the data link layer (such as QoS requirements). In this paper, we propose a simple cross-layer downlink scheduler for SDMA based systems. As an example, it is implemented on an OFDMA/SDMA system. Analysis and simulations are given to show the effectiveness of our proposal.