论文标题
HARQ辅助多RIS系统的中断性能分析
Outage Performance Analysis of HARQ-Aided Multi-RIS Systems
论文作者
论文摘要
可重新配置的智能表面（RIS）最近由于对富含功耗的大量模仿而具有先天的优势，引起了人们的兴趣。在本文中，我们在混合自动重复请求（HARQ）的帮助下研究了多RIS系统的中断性能，以提高RIS系统的可靠性，在此，在此，在此，目的地接收到的通道是由RICIAN褪色建模的，并且相移设置仅取决于视线（LOS）组件。 I型HARQ和HARQ下的确切和渐近中断概率均具有结合（HARQ-CC）方案。特别是可进行的渐近结果，使我们有能力获得有意义的HARQ辅助多RIS系统的见解。一方面，我们发现I型和HARQ-CC方案都可以实现与最大数量的HARQ回合相等的多样性。另一方面，获得最佳相对于中断概率最小化的最佳相移设置的闭合形式表达。最佳解决方案表明反射链路方向应与直接链路LOS组件一致。最后，通过蒙特 - 卡洛模拟验证了分析结果。
Reconfigurable intelligent surface (RIS) has recently attracted a spurt of interest due to its innate advantages over Massive MIMO on power consumption. In this paper, we study the outage performance of multi-RIS system with the help of hybrid automatic repeat request (HARQ) to improve the RIS system reliability, where the destination received channels are modeled by Rician fading and the phase shift setting only depends on the line-of-sight (LoS) component. Both the exact and asymptotic outage probabilities under Type-I HARQ and HARQ with chase combining (HARQ-CC) schemes are derived. Particulary, the tractable asymptotic results empower us to derive meaningful insights for HARQ-aided multi-RIS system. On the one hand, we find that both the Type-I and the HARQ-CC schemes can achieve full diversity that is equal to the maximal number of HARQ rounds. On the other hand, the closed-form expression of the optimal phase shift setting with respect to outage probability minimization is obtained. The optimal solution indicates that the reflecting link direction should be consistent with direct link LoS component. Finally, the analytical results are validated by Monte-Carlo simulations.
