In this paper, downlink multigroup multicast transmission in the ultra-dense low Earth orbit satellite constellation networks with full frequency reuse is studied. Multicast transmission significantly improves the system performance compared with point-to-point transmission. However, multicast capacity is constrained by the signal to interference and noise ratio (SINR) of bottleneck users in each group. To tackle this problem, we propose an alternating optimization-based joint power allocation and cooperative beamforming algorithm (AO-JPACB) to enhance the SINR of the bottleneck users and improve the system capacity. Simulation results show that the proposed AO-JPACB algorithm can improve the system capacity compared to single-satellite schemes.

中文翻译：

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超密集低地球轨道卫星星座网络的联合功率分配和协作模拟波束成形

本文研究了全频复用的超密集近地轨道卫星星座网络中的下行多组播传输。与点对点传输相比，组播传输显着提高了系统性能。然而，组播容量受到每个组中瓶颈用户的信干噪比（SINR）的限制。为了解决这个问题，我们提出了一种基于交替优化的联合功率分配和协作波束成形算法（AO-JPACB）来增强瓶颈用户的信噪比并提高系统容量。仿真结果表明，所提出的AO-JPACB算法与单卫星方案相比可以提高系统容量。