有效的基于软频率复用长期演进femtocell网络的小区间干扰协调方案

家庭基站是一种小体积、低发射功率的基站，它为长期演进(LTE) femtocell双层网络提供更好室内覆盖的同时也增加了整个系统的容量。然而，femtocell和宏基站(MeNB)之间的干扰不容小觑。针对二者间的干扰问题，提出一种基于软频率复用(SFR)的有效的LTE femtocell网络的小区间干扰协调(ICIC)方案。该方案中，为避免共信道干扰，先对宏小区进行SFR频域资源分配，然后让femtocell用户使用宏基站未占用的频域资源；并且当femtocell位于宏小区中心区域时，不使用同一扇区边缘区域占用的频带。仿真结果表明，此方案减小了不同类型用户间的干扰，整个网络的吞吐量比没有使用ICIC技术的情况提高了14%，同时小区边缘用户的平均吞吐量至少提高了34%。

Effective inter-cell interference coordination scheme in long term evolution femtocell network based on soft frequency reuse

Femtocell is a small low powered base station which can provide an increase in system capacity and better indoor coverage for two-tier Long Term Evolution (LTE) network. However, interference problem between the femtocell and the Microcell eNodeB (MeNB) should be solved in advance. Concerning the interference between them, an effective Inter-Cell Interference Coordination (ICIC) scheme using Soft Frequency Reuse (SFR) was proposed in LTE femtocell system. Under the macrocell pre-allocating frequency band by the SFR, the femtocell user equipments chose sub-bands which were not used in the macrocell sub-area to avoid co-channel interference. At the same time, when the femtocell was located in the center of a macrocell, it was not going to select the sub-bands which were occupied by the boundary region of the same sector. Simulation results show that the proposal scheme improves the throughput performance of overall network by 14% compared to the situation without ICIC, and the average throughput of cell edge users increases by 34% at least.