The effect of imperfect power control on outage probability in a cellular mobile system

Recently, a new centralized power control scheme for cellular mobile systems, called the stepwise maximum interference removal algorithm (SMIRA), has been proposed and shown to have a better performance than the stepwise removal algorithm (SRA) with only a slight increase in computational complexity. In this paper, we study the effects of finite power dynamic range and quantized power levels on the performance of the SMIRA algorithm. Two techniques, the lower bound technique (LBT) and the upper bound technique (UBT), are used to enforce transmitter powers to satisfy the finite power range constraint. Via computer simulations, we found that the performance of the LBT is significantly better than that of the UBT. Moreover, numerical results show that, for a protection ratio of smaller than 20 dB, it is sufficient to quantize transmitter powers into 32 levels when the power range is 30 dB.