This letter considers a two-tier downlink interference problem as a case of study, where macrocell user equipment (UE) shares the same frequency band with femtocell UE and suffers from severe cross-tier interference. Power control is one of the spectrally-efficient techniques used to mitigate the interference. However, it harms femtocell users since the femto base station reduces the transmitted power. In this letter, a novel scheme is proposed to jointly suppress the interference on the macrocell users, and preserve the high data rates required by femtocell users under centralized radio access network. The analytical results well agreed with the conducted simulations, and showed the superiority of the proposed scheme in achieving higher throughput compared to existing schemes.

中文翻译：

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集中式 RAN 中基于预编码的跨层干扰缓解

这封信将两层下行链路干扰问题作为研究案例，其中宏小区用户设备 (UE) 与毫微微小区 UE 共享同一频段，并遭受严重的跨层干扰。功率控制是用于减轻干扰的频谱效率高的技术之一。然而，由于毫微微基站降低了发射功率，它损害了毫微微蜂窝用户。在这封信中，提出了一种新颖的方案来共同抑制对宏小区用户的干扰，并在集中无线接入网络下保持毫微微小区用户所需的高数据速率。分析结果与进行的模拟非常吻合，并表明与现有方案相比，所提出的方案在实现更高的吞吐量方面具有优势。