Improving Energy Efficiency of Femtocell System

• Main Authors: Wei-HsuanHsu, 徐維旋
• Other Authors: Wen-Kuang Kuo
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/34010067628574570757

碩士 === 國立成功大學 === 電腦與通信工程研究所 === 104 === Recently in the communication system, user request more capacity and more coverage with the low cost, and femtocell base station is a promising technical which provide higher data transmission rate and lower energy consumption, and it is suitable for indoor environment, such as enterprise building, home network. This paper aim to maximize the energy efficiency for downlink, also find how will the femtocell network performance be influenced if we increase more users in the indoor environment. We consider flow distribution, power control, and formulate the energy efficiency problem. The original model is a mixed integer nonlinear fractional which is NP-hard and hardly solvable. We should process some transforms on it than we can find the optimal solution based on the Branch and bound framework. Within Branch and Bound framework, we employ a reformulation linearization technique (RLT) to relax the nonlinear terms. And we use Charnes-Cooper transform to simplify the fractional form of objective function, then the modified model is a mixed integer linear programming problem. Solved by CPLEX, we get the solution that has low cost and high transmission rate. Finally, we investigate the influences if we increase users in the femtocell system.