Performance of adaptive sleep period control for wireless communications systems

Sleep mode operation is widely used in wireless communications systems to reduce power consumption of portable devices. The optimal length of sleep period is affected by the message interarrival time that varies over time. In this letter, the adaptive schemes to control sleep period is investigated. We first generalize the scheme in [5] and then suggest another variant of the generalized scheme, where the sleep period increases or decreases exponentially depending on whether a message arrives or not. The performance of these two schemes is evaluated by using Markov analysis. Numerical results show that the schemes operate effectively when the system is lightly loaded, which is the operating environment of sleep mode in practice.