Dynamic time-division duplex (D-TDD) has emerged as an effective solution to accommodate the unaligned downlink and uplink traffic in small cell networks. However, the flexibility of traffic configuration also introduces additional inter-cell interference. In this letter, we study the effectiveness of applying fractional frequency reuse (FFR) as an interference coordination technique for D-TDD small cell networks. We derive the analytical expressions of downlink and uplink mean packet throughput (MPT), then study a network parameter optimization problem to maximize MPT while guaranteeing each user's throughput. Numerical results corroborate the benefits of the proposed FFR-based D-TDD in terms of improving throughput.

中文翻译：

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D-TDD和FFR下Small Cell网络的吞吐量分析

动态时分双工 (D-TDD) 已成为适应小型蜂窝网络中未对齐的下行链路和上行链路流量的有效解决方案。然而，流量配置的灵活性也引入了额外的小区间干扰。在这封信中，我们研究了应用部分频率复用 (FFR) 作为 D-TDD 小蜂窝网络的干扰协调技术的有效性。我们推导出下行和上行平均分组吞吐量（MPT）的解析表达式，然后研究网络参数优化问题，以在保证每个用户的吞吐量的同时最大化MPT。数值结果证实了所提出的基于 FFR 的 D-TDD 在提高吞吐量方面的好处。