论文标题
智能反映表面辅助反向散射通信
Intelligent Reflecting Surface-Aided Backscatter Communications
论文作者
论文摘要
我们介绍了一种新型的系统设置，在智能反射表面（IRS）的存在下，反向散射设备可运行。特别是，我们研究了IRS协助的Bistatic反向散射通信（BackCom）系统。 IRS处的相移与载体发射极的发射光束向量共同优化，以最大程度地减少载体发射极处的发射功耗，同时保证所需的背面性能。 IRS多种反射引起的独特信道特性使优化问题高度非凸。因此，我们共同利用少量最大化算法和半决赛弛豫技术为最佳IRS相移设计提供了近似解决方案。我们还将我们的分析结果扩展到单稳态背科系统。数值结果表明，IRS的引入带来了发射功率的大量降低，即使具有中等的IRS尺寸，可以将其转换为非IRS辅助后COMCOM系统的范围增加。
We introduce a novel system setup where a backscatter device operates in the presence of an intelligent reflecting surface (IRS). In particular, we study the bistatic backscatter communication (BackCom) system assisted by an IRS. The phase shifts at the IRS are optimized jointly with the transmit beamforming vector of the carrier emitter to minimize the transmit power consumption at the carrier emitter whilst guaranteeing a required BackCom performance. The unique channel characteristics arising from multiple reflections at the IRS render the optimization problem highly non-convex. Therefore, we jointly utilize the minorization-maximization algorithm and the semidefinite relaxation technique to present an approximate solution for the optimal IRS phase shift design. We also extend our analytical results to the monostatic BackCom system. Numerical results indicate that the introduction of the IRS brings about considerable reductions in transmit power, even with moderate IRS sizes, which can be translated to range increases over the non-IRS-assisted BackCom system.
