论文标题
大规模MIMO的无赠予随机访问的序言碰撞减少的方法
An Approach to Preamble Collision Reduction in Grant-Free Random Access with Massive MIMO
论文作者
论文摘要
在本文中，我们研究了具有大量多重输入多重输出（MIMO）系统的无授予随机访问。我们首先表明，基于MIMO的大量赠款随机访问的性能主要取决于序言碰撞的可能性。这意味着，尽管天线的数量可以任意较大，但成功的数据包传输的（平均）数量可以受到序言数量的限制。然后，我们提出了一种使用叠加序列的概念（s-preambles）的概念，而无需增加前序数量的序言碰撞的方法。由于可以在已知未使用的S-捕集内容时进行共轭光束成型的通道估计，因此得出了一种简单的方法来检测未使用的S preambles，并为特殊情况（具有2个preambles的叠加）分析了其性能。基于分析和仿真结果，可以证实，所提出的S-Preambles的方法可以以与常规方法相同的光谱效率来提高成功概率。
In this paper, we study grant-free random access with massive multiple input multiple output (MIMO) systems. We first show that the performance of massive MIMO based grant-free random access is mainly decided by the probability of preamble collision. The implication of this is that although the number of antennas can be arbitrarily large, the (average) number of successful packet transmissions can be limited by the number of preambles. Then, we propose an approach to preamble collision reduction without increasing the number of preambles using the notion of superpositioned preambles (S-preambles). Since the channel estimation for conjugate beamforming can be carried out when unused S-preambles are known, a simple approach is derived to detect unused S-preambles and its performance is analyzed for a special case (superpositions with 2 preambles). Based on analysis and simulation results, it is confirmed that the proposed approach with S-preambles can increase the success probability with the same spectral efficiency as the conventional approach.
