Strategies for Spectrum Allocation in OFDMA Cellular Networks

The use of orthogonal frequency division multiple access (OFDMA) in Long Term Evolution (LTE) and WiMax cellular systems mitigates downlink intra-cell interference by the use of sub-carriers that are orthogonal to each other. Intercell interference, however, limits the downlink performance of cellular systems. In order to mitigate inter-cell interference, various techniques have been proposed. These techniques are generally divided into static and dynamic techniques. In static techniques, resources allocated for base stations are fixed, while they are adaptively allocated in the dynamic techniques. Although static and dynamic frequency reuse techniques, address the issue of interference, they do not have any mechanism to sustain a disruption or to maintain a allocation in a distributed manner. Hence, the need for distributed frequency allocation. In this paper we briefly discuss the merits of distributed spectrum allocation algorithms for cellular networks and also present an assessment of static interference schemes, and evaluate overall performance of the system in terms of the SINR, and spectral efficiency by adjusting different input parameters. In addition, we study an adaptive frequency reuse algorithm presented by and compare it with the static techniques.