Clustering Based Dynamic Inter-cell Interference Coordination In OFMDA Cellular Networks

To meet the ever increasing data rate requirement of mobile users,3GPP Long TermEvolution (LTE) targets higher spectrum efficiency, shorter user delay and higher cell edgethroughput to achieve greater system capacity and users’ quality of service (QoS)requirement. In OFDM systems, intra-cell interference can be neglect while inter-cellinterference (ICI) becomes the main interference sources in the system which can besuppressed by inter-cell interference coordination (ICIC).Soft frequency reuse(SFR) and fractional frequency reuse(FFR) are two classicmethods of ICIC, which make the spectrum reuse factor of cell edge to be3and thefrequency at neighbor cells edge are orthogonal. The cell center user who get far awayfrom the interfering neighbor cells and experience low interference can achieve thespectrum reuse factor of1. To increase the spectrum efficiency and throughput of thesystem further, a number of dynamic frequency reuse methods are learned and researchedto make the system spectrum reuse factor close to1.In this paper, we proposed sector factor based dynamic SFR algorithm andclustering-based FFR frequency resource exchange algorithm in multi-cell resourceallocation, in which the frequency and power resource are dynamically assigned to eachuser. Both are have innovative points in several aspects, like scenario design, resourceallocation algorithm and iterative exchange process. The dynamic frequency allocationprocess can get adapt to the practical system and is supposed to improve the spectrumefficiency and throughput of the system. The proposed two algorithms are simulated withthe static SFR and FFR methods on the LTE system-level simulator, and the results provedthat the proposed methods outperforms the static SFR and FFR methods in the throughputand fairness of the system.