Adaptive Transmission of QoS-Guaranteed Traffic over MIMO Wireless Links

In this paper, we consider the problem of transmission of a bursty data-packet traffic over MIMO space-time diversity fading channels. Aiming at minimizing the packet loss probability due to buffer overflow at the data link layer, we propose a cross-layer analytical framework for transmission policy design which directly satisfies a packet error rate (PER) constraint at the physical layer. Particularly, we present a power and rate adaptation policy for coded M-QAM modulation schemes that are implemented in conjunction with a MIMO diversity system. To enable the transmission policy design, we use a statistical model to characterize the buffer overflow derived from a large deviations result. Numerical results demonstrate that the proposed adaptation policy significantly improves the packet-loss performance for bursty data traffic over MIMO fading channels, when compared to others adaptive solutions.