Frequency Reuse Scheme With Three Regions in Cooperative Relaying For Multi-cell OFDMA Systems

Cooperative relaying has shown as promissing approach to improve transmission reliability in cellular network. In this paper cooperative relaying and frequency reuse partitioning are exploited to avoid the co-channel cell interference (CCI) in the downlink multi-cell OFDMA systems. In our system layout, each cell is divided into three regions: the central region, the middle region and the edge region. The frequency reuse factor (FRF) is set to 1 in the central region. Depending on the number of sectors in the middle and the edge region, the FRFs of 3, 7/3, 7/4, 4 and 6 have been applied. A fixed relay station (RS) by sector, which amplifies and forwards the received signal to the mobile, is placed at the limit of the middle region and the edge region. Numerical results are presented to demonstrate the effectiveness of the proposed cooperative scheme for CCI mitigation in the edge of the cell.