Self-organised dynamic resource allocation scheme using enhanced fractional frequency reuse in long term evolution-advanced relay-based networks

Inter-cell interference (ICI) from neighbouring cells is a major challenge that severely degrade the performance of cellular mobile communication systems, particularly for cell-edge users. An efficient technique to mitigate ICI is interference coordination. The most common ICI coordination technique is fractional frequency reuse (FFR). Furthermore in order to effectively improve cell-edge performance in terms of coverage extension and throughput, the third generation partnership project introduced the use of relays in long term evolution-advanced (LTE-A) networks. This paper presents a self-organized dynamic resource allocation scheme using enhanced FFR (SODRA-EFFR) which dynamically allocates resources to cell inner and outer regions in LTE-A relay-based networks. In this scheme, the downlink power and frequency resources allocation for cell inner and outer regions and the outer regions frequency resources allocation between evolved nodeBs (eNBs) and relay stations in each cell are dynamically allocated based on coordination between neighbouring eNBs and relay stations through LTE-X2 interfaces. The performance of the proposed scheme without and with relays is evaluated using MATLAB simulations and compared with different reference resource allocation schemes. Simulation results show that the proposed scheme improves cell-edge performance and achieves high degree of fairness among users’ equipment (UEs) compared with reference resource allocation schemes.