Probabilistic QoS measures for optimal power control in fading channels

Abstract

In this paper, we focus on computing the outage probability by allocating optimal transmitting powers when the system has a large number of transmitter-receiver pairs and each mobile has an enlarged margin of SIR. By introducing a probability QoS measure scheme, we derive the Moment Generating Function (MGF) expressions for different fading channels. Applying Chen off bound theorem, Large Deviation theorem and MGF, we give the simple and effective expression of outage probability with the large transmitter-receiver pairs M. When M becomes larger, the upper bounds of outage probability are close to the exact outage probability curves. At the same time, for large M and lower SIR thresholds, the outage probabilities are small and very close to the exact outage probability. Numerical results have shown that each user only needs to know its own channel gain to its assigned base station and its own output at its assigned base station to update the transmitter power in order to maintain a desired Signal to Interference Ratio (SIR) and QoS requirement at the receiver.