Stable Distributed Power Control with High SIR Target for Cellular Wireless Communication Systems

Abstract – In this paper we analyse the convergence properties of distributed power control (DPC) and propose an improved algorithm to overcome the weakness of DPC. The DPC algorithm can only work in the region of low signal to interference ratios (SIRs). When the user SIR target is high, the transmit power will diverge to infinite. Furthermore, before the system converges, the DPC algorithm may cause SIR fluctuations which makes the system unstable. Our proposed algorithm DPCH is designed for high SIR environment and can solve the limitations of DPC. Specifically, there is no SIR fluctuation in DPCH before the system converges. The predicted convergence properties of DPCH are verified by computational experiments. The numerical results demonstrate that DPCH can offer better performance than DPC in terms of stability and power saving, especially in the high SIR environment, while the convergence rate of DPCH is slightly slower than that of DPC in the low SIR environment.