Controlling QoS by Integrated Power Control and Link Adaptation in Broadband Wireless Networks

We propose and analyze the performance of an algorithm for integrated power control and adaptive modulation/coding to achieve a speciied range of packet error rate for real-time applications in broadband wireless packet-switched networks. The algorithm applies the Kalman-lter method 1] for power control, and adapts packet transmission to an appropriate modulation level, according to the packet error requirement, and the radio and interference conditions. A new criterion for maintaining stable transmission power is derived. Based on the criterion, the proposed technique performs the link adaptation and adjusts transmission power to achieve the speciied packet error rate. The eeectiveness of the proposed method is demonstrated by several numerical examples.