The explosive growth of bandwidth-hungry Internet applications have led to the rapid development of new generation mobile network technologies that are expected to provide broadband access to the Internet in a pervasive manner. For example, 6G networks are capable of providing high-speed network access by exploiting higher frequency spectrum; high-throughout satellite communication services are also adopted to achieve pervasive coverage in remote and isolated areas. In order to enable seamless access, integrated satellite-terrestrial communication networks (ISTCNs) have emerged as an important research topic, which aim to provide high-speed and pervasive network access by integrating broadband terrestrial mobile networks with satellite communication systems. As the terrestrial networks have begun to use higher frequency bands that overlap with those of the satellite networks, the satellite terminals can potentially access the terrestrial networks in an integrated manner. However, more efficient spectrum management techniques are needed to reduce the congestion and interference caused by spectrum sharing. In this article, we seek to improve satellite-terrestri-al spectrum sharing performance by introducing non-orthogonal multiple access (NOMA) and cognitive radio (CR) in the spectrum access of the ISTCN. Through fusing NOMA and CR, CR-NO-MA allows multiple satellite terminals to access both the idle and busy spectrum simultaneously, which will achieve high-efficiency full spectrum access. Furthermore, some open research and challenges for the spectrum sharing of the ISTCN are discussed.

中文翻译：

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基于NOMA和CR的6G星地一体化通信网络频谱共享


高带宽互联网应用的爆炸性增长导致了新一代移动网络技术的快速发展，这些技术有望以普遍的方式提供对互联网的宽带接入。例如，6G网络能够利用更高的频谱提供高速网络接入；还采用高吞吐量的卫星通信服务，实现偏远地区的普遍覆盖。为了实现无缝接入，卫星地面综合通信网络（ISTCN）成为一个重要的研究课题，旨在通过将宽带地面移动网络与卫星通信系统集成来提供高速、普适的网络接入。由于地面网络已经开始使用与卫星网络重叠的更高频段，卫星终端有可能以集成方式接入地面网络。然而，需要更有效的频谱管理技术来减少频谱共享造成的拥塞和干扰。在本文中，我们寻求通过在 ISTCN 频谱接入中引入非正交多址（NOMA）和认知无线电（CR）来提高星地频谱共享性能。 CR-NO-MA通过融合NOMA和CR，允许多个卫星终端同时接入空闲和繁忙频谱，从而实现高效的全频谱接入。此外，还讨论了 ISTCN 频谱共享的一些开放研究和挑战。