Total energy minimization through dynamic station-user connection in macro-relay network

In this paper, we investigate the energy efficiency problem in macro-relay network. Considering users with different locations and rate requirements, our objective is to serve all users with strict rate guarantee and meanwhile minimize the total energy consumption of the network. First, we formulate an integer optimization problem with the variables as stationuser connections. Then we analyze the complexity of the optimal brute-force search (BFS) method and propose a practical algorithm, i.e., serving station selection for energy minimization (SSSEM). The proposed SSSEM algorithm dynamically alters user's serving station according to both the radio frequency energy and the circuit energy, thus minimizing the total energy consumption of the network. Extensive simulations are conducted and the results show that, compared with existing schemes, the proposed SSSEM algorithm can significantly reduce the total energy consumption of the network, and meanwhile achieve the optimum of BFS.