Long-Term Evolution-Advanced (LTE-A) is a standard adopted for fourth-generation mobile communication systems. To support various mobile applications, the Third-Generation Partnership Project (3GPP) defined multiple Quality-of-Service (QoS) class identifiers so that application data can be treated differently to meet the QoS requirements. Meanwhile, to prolong the battery lifetime of mobile devices, the 3GPP specified the Discontinuous Reception (DRX) mechanism for LTE-A systems as a power saving function. More energy saving often implies performance degradation or worse QoS support. In this study, we address the issue of energy saving with DRX while maintaining QoS support for LTE-A systems. Unlike previous studies that analyzed average packet delay under the DRX mechanism, we evaluate the effect on packet loss ratio due to the violation of delay bound requirements. The problem is formulated by maximizing the energy saving efficiency subject to the constraint that the packet loss ratio does not exceed a predetermined threshold. We derive packet loss ratio as a function of DRX parameters and propose an algorithm to efficiently configure these parameters. The proposed analytical model is verified through simulations. According to numerical results, the energy saving efficiency achieved by the proposed algorithm is very close to that of the optimum setting.
- Delay bound
- Discontinuous Reception (DRX)
- Long-Term Evolution-Advanced (LTE-A)
- Packet loss ratio
- Quality-of-Service (QoS)