A Power Efficiency Based Delay Constraint Mechanism for Mobile WiMAX Systems

In Mobile WiMAX systems, a power saving mechanism, which operates using sleep- and wake- modes, extends the battery lifetime of a Mobile Station (MS) but at the expense of the frame response delay. These two performance metrics, power consumption and delay, are reciprocally affected by sleep mode parameters such as initial sleep window Tmin, and final sleep window Tmax. This paper focuses on minimizing energy consumption under a guaranteed delay performance using a Power Efficiency based Delay Constraint (PEDC) mechanism which finds jointly-optimal parameters Tmin and Tmax. Simulation results validate that our proposed PEDC mechanism indeed minimizes consumed power for a specified frame response delay. In addition, in some cases, it can save up to 60% of consumed power compared to the original power saving mechanism in Mobile WiMAX.