High-altitude platform station (HAPS) systems are considered to have great promise in the multi-tier architecture of the sixth generation (6G) and beyond wireless networks. A HAPS system can be used as a super macro base station (SMBS) to communicate with users directly since there is a significant line-of-sight (LoS) link between a HAPS and terrestrial users. One of the problems that HAPS SMBS systems face, however, is the high spatial correlation between the channel gain of adjacent users, which is due to the LoS link between the HAPS and terrestrial users. In this paper, in addition to utilizing the spatial correlation of channel gain between multiple users to improve user services, we consider correlated channel gain for each user. In the proposed method, terrestrial users with a high spatial correlation between their LoS channel gain are grouped into NOMA clusters. Next, an algorithm is proposed to allocate power among terrestrial users to maximize the total rate while satisfying the quality-of-service (QoS) and successive interference cancellation (SIC) conditions. Simulation results show that a HAPS SMBS has superior data rate and energy efficiency in comparison to a terrestrial BS.

翻译：高纬度平台站(HAPS)系统被认为在第六代(6G)和无线网络以外的多层结构中有很大的希望。HAPS系统可以用作超级宏观基站(SMBS),直接与用户联系,因为HAPS和地面用户之间有相当长的视线(LOS)联系。HAPS SMBS系统所面临的一个问题是邻近用户的频道收益之间的高度空间关系,这是由于HAPS和地面用户之间的LOS联系。在本文中,除了利用多个用户之间的频道收益空间关系来改进用户服务外,我们考虑每个用户的频道收益是相关的。在拟议方法中,其LOS频道收益具有高度空间相关性的地面用户被归为NOMA集群。接下来,建议一种算法,在满足服务质量(QOS)和连续干扰取消(SIC)条件的同时,在地面用户之间分配最大总速率的电力。模拟结果表明,HAPS SMBS数据率和能源效率高于地面BS。