School of Electrical Engineering and Intelligentization, Dongguan University of Technology, Dongguan 523808, China.
Sensors (Basel). 2023 Jun 21;23(13):5791. doi: 10.3390/s23135791.
Previous works only focus on the optimization design for the dual-hop cooperative ambient backscatter communication (AmBC) system with single-relay selection. The impact of relay selection on the outage performance of dual-hop cooperative AmBC systems is still missing. Motivated by this, in this paper, we investigate the outage performance of a dual-hop cooperative AmBC system with single-relay selection, where the backscatter link shares the receiver with the cellular link and the harmful direct-link interference (DLI) is mitigated by using successive interference cancellation (SIC). In the system considered, the selected relay has dual functions. One is to forward message for the cellular link, and the other is to act as the radio-frequency (RF) source for the backscatter device (BD). Specifically, after proposing two novel single-relay selection schemes (RSSs), namely reactive RSS and proactive RSS, we derive the closed-form outage probability (OP) expressions for both RSSs, which can be performed in a distributed manner. To gain more insights, the asymptotic OPs at high signal-to-noise ratio (SNR) are explored and the outage performance comparison between the reactive RSS and proactive RSS are also provided. Results show that the proposed reactive RSS is outage-optimal among all possible single-relay selection schemes. The theoretical analysis is validated by Monte Carlo simulations. The results also show that the relay selection scheme, the number of relays, the location of BD, and the reflection coefficient of BD have great impact on the outage performance of cooperative AmBC systems.
先前的工作仅关注于具有单中继选择的双跳协作环境后向散射通信（AmBC）系统的优化设计。中继选择对双跳协作 AmBC 系统中断性能的影响仍未得到研究。受此启发，本文研究了一种具有单中继选择的双跳协作 AmBC 系统的中断性能，其中后向散射链路与蜂窝链路共享接收器，并且通过使用连续干扰消除（SIC）来减轻有害的直传链路干扰（DLI）。在所考虑的系统中，选择的中继具有双重功能。一个是为蜂窝链路转发消息，另一个是作为后向散射设备（BD）的射频（RF）源。具体来说，在提出两种新颖的单中继选择方案（RSS），即反应性 RSS 和主动 RSS 之后，我们推导出了这两种 RSS 的闭式中断概率（OP）表达式，这些表达式可以以分布式方式执行。为了获得更多的见解，还探讨了高信噪比（SNR）下的渐近 OP，并提供了反应性 RSS 和主动 RSS 之间的中断性能比较。结果表明，在所提出的所有可能的单中继选择方案中，反应性 RSS 是中断最优的。通过蒙特卡罗模拟验证了理论分析。结果还表明，中继选择方案、中继数量、BD 的位置和 BD 的反射系数对协作 AmBC 系统的中断性能有很大影响。
