Base Station Operation and User Association Mechanisms for Energy-Delay Tradeoffs in Green Cellular Networks

TLDR

Energy efficiency is a key design goal in wireless cellular networks, driven by growing environmental and economic concerns. The study develops a theoretical framework for base‑station energy saving that jointly addresses dynamic BS operation and user association. The authors formulate a total‑cost minimization that balances flow‑level performance and energy use, propose an optimal energy‑efficient user‑association policy with distributed convergence, and present greedy‑on/off and heuristic algorithms for base‑station switching that require minimal signaling. Simulations show that the proposed algorithms substantially reduce energy consumption across diverse practical settings.

Abstract

Energy-efficiency, one of the major design goals in wireless cellular networks, has received much attention lately, due to increased awareness of environmental and economic issues for network operators. In this paper, we develop a theoretical framework for BS energy saving that encompasses dynamic BS operation and the related problem of user association together. Specifically, we formulate a total cost minimization that allows for a flexible tradeoff between flow-level performance and energy consumption. For the user association problem, we propose an optimal energy-efficient user association policy and further present a distributed implementation with provable convergence. For the BS operation problem (i.e., BS switching on/off), which is a challenging combinatorial problem, we propose simple greedy-on and greedy-off algorithms that are inspired by the mathematical background of submodularity maximization problem. Moreover, we propose other heuristic algorithms based on the distances between BSs or the utilizations of BSs that do not impose any additional signaling overhead and thus are easy to implement in practice. Extensive simulations under various practical configurations demonstrate that the proposed user association and BS operation algorithms can significantly reduce energy consumption.