A Novel Multi-Cell OFDMA System Structure using Fractional Frequency Reuse

In this paper, we propose a novel frequency reuse scheme for multi-cell orthogonal frequency division multiplexing access (OFDMA) systems for co-channel interference reduction. Each cell is partitioned into three sectors. All the available subcarriers are divided into two groups. One is reused in the central region of the sectors, and another is divided into three parts used orthogonally for the edge of the three sectors (no overlap). Which subcarrier group a user can use is dependent on the location or the received signal to interference plus noise ratio (SINR) of the user. Thus, intra-cell orthogonality is guaranteed, and inter-cell interference can be greatly reduced. All the subcarriers may use the same transmit power in this scheme. Simulation results show that this scheme can bring higher system throughput and lower CCI, and it also can increase the data rate at the cell edge.