A Multilevel Soft Frequency Reuse Technique for Wireless Communication Systems

A multilevel soft frequency reuse (ML-SFR) scheme and a resource allocation methodology are proposed for wireless communication systems. In the proposed ML-SFR scheme, there are $2hbox{N}$ power density limit levels, achieving a better interference pattern and further improving the cell edge and the overall data rate compared with the traditional two-level SFR scheme. The detailed design of an eight-level SFR scheme is demonstrated. Numerical results show that the cell-edge spectrum efficiency is increased to five times of that of reuse 1, and the overall spectrum efficiency is improved by 31%. The ML-SFR can be utilized in the current 4G system and would be a candidate key technology for future 5G systems.