Modeling of Mobility-Aware RRC State Transition for Energy-Constrained Signaling Reduction

Mobile devices are becoming more chatty in emerging wireless networks due to the machine-type-communication and always-on applications. On the other hand, the densely deployed heterogeneous networks cause more frequent handovers. From the network's perspective, the increase in background traffic and handovers increases the signaling load due to frequent state transitions between idle and connected states. From the user's perspective, staying in connected state over a long period of time results in higher energy consumption. To analyze the tradeoff between the connected and idle states, we develop a closed-form mathematical model of state transition process, based on the framework of alternating renewal process. The mobility-aware user-specific model enables various types of optimization with respective to reduction of signaling overhead and energy consumption. In this paper we apply the developed model to achieve the minimum amount of signaling load by optimizing the inactivity timer, subjected to the energy consumption constraint.