Enhancing cell edge user performance is an important and challenging issue for cellular mobile communication systems. The next generation cellular mobile system, 3GPP long term evolution （LTE）, aims at improving cell edge user performance through effective inter cell interference coordination （ICIC） and spectrum resource allocation schemes. An adaptive soft frequency reuse （ASFR） algorithm is proposed, aiming at optimizing the system throughput while guaranteeing the minimum data rate requirements for both cell center and cell edge regions. The ASFR algorithm can adaptively adjust the major and minor subcarriers, and their respective transmit power in each cell according to the system traffic loads. In the ASFR, the optimal resource allocation in each single cell is first determined by using exhaustive search and greedy descending methods. Then the single cell resource allocation is repeated iteratively among all cells until the system throughput does not change any more. Simulation results show that the ASFR algorithm yields an SFR resource allocation after a number of internal iterations. It is also shown that the ASFR algorithm improves the cell edge user throughput and achieves higher system throughput compared with several traditional frequency allocation schemes. These advantages reveal that the proposed algorithm is more preferred for the LTE system.
Journal of Computer Research and Development
soft frequency reuse
inter-cell interference coordination
orthogonal frequency division multiple access （OFDMA）
long term evolution （LTE）
qianmanli@ict．ac．cnQian Manli, born in 1986. PhD candidate in the Institute of Computing Technology （ICT）, Chinese Academy of Sciences （CAS） since 2007. Her main research interests include radio resource management, cross-layer design and optimization in wireless communication networks.
Li Yonghui, born in 1975. Associate professor and PhD supervisor in the University of Sydney. His main research interests include wireless sensor networks, cognitive radio, cooperative communications,network coding, etc（yonghui, li@sydney, edu. au）.
Huang 2010. radio design professor researc 1982. PhD and ICT, CAS since h interests include resource management, cross-layer and optimization in wireless communication networks（huangyiOl@ict, ac. cn）.
Zhou Yiqing, born in 1975. Professor and PhD supervisor in ICT, CAS. Her main research interests include MIMO, （）FDM, multicarrier CI）MA, interference cancellation, wireless multiple access,channel coding, etc（zhouyiqing@ict, ac. cn）.
Shi Jinglin, born in 1972. Professor and PhD supervisor in ICT, research interests incl wireless communication（ si ude broadband l@iet, ac. cn）.
Yang Xuezhi, born in 1970. PhD research scientist in Huawei Technology Co. , Ltd. His main research interests include information theory, signal processing, smart antenna, MIMO, ICIC, HetNet,QoS, etc（yangxuezhi@huawei. com）.