基于NOMA的星地协作网络性能分析

Performance Analysis of NOMA-based Satellite-Terrestrial Cooperation Network

随着星地融合网络的不断发展,如何进一步提高有限的卫星资源利用率,受到了国内外专家学者的广泛关注。因此,提出了一种基于非正交多址(Non-Orthogonal Multiple Access,NOMA)技术的星地协作网络传输方案。首先,假设卫星与用户之间不存在直传链路,中继节点以译码转发(Decode-and-Forward,DF)方式实现卫星与用户间的协作通信;其次,根据卫星信道服从阴影莱斯分布、地面信道服从Nakagami-m信道的情况,推导出用户中断概率的精确表达式、高信噪比下的近似表达式和系统遍历容量;最后,通过仿真验证理论推导的正确性和将NOMA技术引入星地协作网络的优越性。

With the continuous development of satellite-terrestrial fusion networks,how to further improve the utilization of limited satellite resources has attracted widespread attention from experts and scholars at home and abroad.Therefore,a satellite-terrestrial cooperation network transmission scheme based on NOMA(Non-Orthogonal Multiple Access)technology is proposed.Firstly,it is assumed that there is no direct transmission link between the satellite and the user,and the relay node implements the cooperative communication between the satellite and the user in DF(Decode-and-Forward)manner.Then according to the satellite channel obeying the shadow Rice distribution and the terrestrial channel obeying the Nakagami-m channel,the accurate expression of user outage probability,the approximate expression under high signal-to-noise ratio and system traversal capacity are derived.Finally,simulation indicates the correctness of the theoretical derivation and the superiority of introducing NOMA technology into the satellite-terrestrial cooperation network.