Joint power allocation and cooperative analog beamforming for ultra-dense low Earth orbit satellite constellation networks

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.