Abstract：In order to solve the load imbalance problem caused by uncertainty of traffic in heterogeneous dense cellular networks, this paper proposes a load balance algorithm through small cell range expansion. The proposed algorithm is based on Partially Observable Markov Decision Process (POMDP). By observing the packets of system user during the perceptual cycle, the next cycle system possible load state can be dopted. Then, the Dynamic Cell Range Expansion (DCRE) offset value is dynamically adjusted to take action in advance, reaching the purpose of optimizing the system load balance. To solve the problem efficiently, a heuristic algorithm is used to approximate and quickly get the suboptimal solution. Simulation results show that the proposed method can achieve load balance optimization in dense hetrogeneous network, and improve the system user throughput and resource utilization rate.
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