Average rate updating mechanism in proportional fair scheduler for HDR

The average rate updating mechanism was first promoted for the starvation problem emerging when some user experiences a sudden drop in channel quality or just keeps on moving backward from the base station under the proportional fair scheduler in the HDR system. Although proportional fair scheduling has received much theoretic research attention recently for its attractive capability on the tradeoff between system utility and fairness, the influence of average rate updating mechanism to the performance of scheduler has been neglected. We point out here that the previous rate update mechanism based on fixed time window is insufficient in keeping the users from starvation. Furthermore, updating the average rate to users with no data to send may not get the overall maximized system utility. We also promote a new average update mechanism as the basis of the proportional fair scheduling algorithm. Simulation and analysis show that this novel design with starvation supervision has better performance over the traditional design.