부산대학교 도서관

Two-tier network is one of the most promising solutions to improve indoor coverage of cellular networks. When macro-tier and femto-tier share frequency spectrum, management of interference as a critical issue, attract much attention from industry and academia. Joint sub-carrier assignment and power control is considered as a way to interference management in orthogonal frequency division multiple access based two-tier networks. In this paper, a joint sub-carrier assignment and power control problem is addressed to maximize femtocells’ total data rate such that the maximum transmit power budget and minimum data rate of users (macro and femto users) are satisfied. This problem is a mixed-integer non-linear programming problem, thus its optimal solution cannot be obtained in polynomial time. So, to tackle this issue, we decompose this problem into two sub-carrier assignment and power control sub-problems. To solve these sub-problems, heuristic algorithms are proposed. The simulation results demonstrate that our proposed algorithms outperform the existing algorithms in terms of femtocells’ total data rate.