AI 中文总结
针对HAPS与地面网络共存时的跨层干扰问题，提出基于反向TDD的传输框架，利用大规模系统分析推导SINR近似，有效抑制干扰，实现接近无干扰性能。
AI 中文摘要
高空平台站（HAPS）预计将与地面网络（TN）共存，以在未来第六代（6G）系统中提供无缝的广域无线连接。然而，HAPS链路的强视距（LoS）传播在频谱共享下引入了严重的跨层干扰。本文提出了一种基于反向时分双工（RTDD）的传输框架，用于集成HAPS-TN系统，其中HAPS和地面基站（BS）以相反传输方向运行，以减轻跨层干扰，同时保持TDD信道互易性。对HAPS和地面链路均采用标准化的3GPP信道模型。为了实现可处理的性能分析，开发了一种解析Kronecker信道模型来近似经验3GPP地面BS信道，在此基础上建立了基于随机矩阵理论（RMT）的大规模系统分析，以推导上行链路和下行链路信干噪比（SINR）的确定性近似。数值结果表明，所提分析与蒙特卡洛模拟之间具有极好的一致性。此外，所提出的RTDD框架有效抑制了跨层干扰，实现了接近无干扰的性能。
英文摘要
High-altitude platform stations (HAPSs) are expected to coexist with terrestrial networks (TNs) to provide seamless wide-area wireless connectivity in future sixth-generation (6G) systems. However, the strong line-of-sight (LoS) propagation of HAPS links introduces severe cross-tier interference under spectrum sharing. This paper proposes a reverse time division duplexing (RTDD)-based transmission framework for integrated HAPS--TN systems, where the HAPS and terrestrial base station (BS) operate in opposite transmission directions to mitigate cross-tier interference while preserving TDD channel reciprocity. Standardized 3GPP channel models are adopted for both HAPS and terrestrial links. To enable tractable performance analysis, an analytical Kronecker channel model is developed to approximate the empirical 3GPP terrestrial BS channel, based on which a random matrix theory (RMT)-based large-system analysis is established to derive deterministic approximations for the uplink and downlink signal-to-interference-plus-noise ratios (SINRs). Numerical results demonstrate an excellent agreement between the proposed analysis and Monte Carlo simulations. Moreover, the proposed RTDD framework effectively suppresses cross-tier interference, achieves near interference-free performance.
