Interference management for rate-constrained moving relay node in a heterogeneous network

Cooperative communication via a moving relay node (MRN) helps resolve both the poor quality of service (QoS) and limited battery-capacity problems of cell-edge vehicle user equipment (VUE). This paper investigates the performance of MRNs in a heterogeneous network (HetNet). MRNs as well as other small cells are expected to coexist in a complex manner. In such a HetNet, the inter-cell interference may degrade the expected improvement of MRNs, especially at the cell-edge. In this paper, we investigate the impact of intercell interference on the performance of MRNs. To alleviate this impact, we first formulated a general optimization problem for which it is intractable to find a global optimal solution. To have a practical solution with low computational complexity, we used a practical interference management algorithm that aimed to ensure that every MRN achieved its required minimum-rate while maximizing total network throughput. In the simulations, the proposed algorithm was observed to improve both the QoS and fairness of MRNs. Numerical results demonstrate that the proposed algorithm can offer an efficient trade-off between the performance of both the victim MRNs and aggressing femtocells.摘要基于移动中继(Mobile Relay Node, MRN)的协作通信主要用于解决小区边缘区域车载用户服务质量(Quality of Service, QoS)无法保障的问题。 鉴于异构网络中小区间干扰可能会影响到移动中继下的车载用户, 本文主要关注移动中继的性能保障问题。 本文首先尝试将其建模为一般的优化问题, 该优化问题可以在保障每个移动中继最小速率需求的前提下最大化整个网络的吞吐量。 由于该问题很难找到全局最优解, 而实际网络中需要低运算复杂度的可实施方案, 为此本文提出了一种简单可行的干扰管理算法。 通过仿真实验可以看到所提出的低复杂度算法能够很好地提升移动中继节点的性能, 并且确保不同移动中继之间的公平性, 同时仿真结果表明本文算法能够更好地均衡车载用户和微小区用户之间的性能。