In this paper, we use satellite-assisted and multi-group multicast mechanisms to relieve ground traffic pressure and improve data transmission efficiency of cell-free massive MIMO systems. We propose to estimate channel state information (CSI) by common pilot scheme. Given the estimated CSI, we derive the closed-form expressions of achievable rate with maximum ratio transmission (MRT) and zero-forcing (ZF) precoding. The correctness of the closed-form expressions is verified through simulations. The results show that with the help of satellite and multicast, the average system spectrum efficiency (SE) can be significantly improved.

中文翻译：

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具有多组多播的卫星辅助无细胞大规模 MIMO 系统

在本文中，我们使用卫星辅助和多组播机制来缓解地面交通压力，提高无小区大规模 MIMO 系统的数据传输效率。我们建议通过公共导频方案来估计信道状态信息（CSI）。给定估计的 CSI，我们推导出具有最大比传输 (MRT) 和迫零 (ZF) 预编码的可实现速率的封闭形式表达式。通过仿真验证了闭式表达式的正确性。结果表明，在卫星和组播的帮助下，平均系统频谱效率（SE）可以得到显着提高。