Well-designed simultaneously transmitting and reflecting RIS (STAR-RIS), which extends the half-space coverage to full-space coverage, incurs wireless communication environments to be smart and reconfigurable. In this paper, we survey how STAR-RIS affects the performance of full-duplex communication systems with the presence of full-duplex users, wherein the base station (BS) and the uplink users are subject to maximum transmission power constraints. Firstly, the weighted sum-rate (WSR) is derived as a system performance metric. Then, we formulate the resource allocation design into an equivalent weighted minimum mean-square-error form and then transform it into several convex sub-problems to maximize the WSR as an optimization problem which jointly optimizes the beamforming and the combining vectors at the BS, the transmit powers of the uplink users, and phase shifts of STAR-RIS. Although the WSR optimization is non-convex, an efficient iterative alternating procedure is proposed to achieve a sub-optimal solution for the optimization problem. Secondly, the STAR-RIS's phase shifts are optimized via the successive convex approximation technique. Finally, numerical results are provided to explain how STAR-RIS improves the performance metric with the presence of full-duplex users.
翻译:首先,加权总和率(WSR)是作为系统性能衡量尺度得出的。然后,我们将资源分配设计发展成一个相当的加权最低平均方程式,然后将其转换成几个相等的子问题,以最大限度地实现WSR,将其作为一个优化问题,共同优化BS的波形成形和组合矢量,使BS的波形和矢量形成最佳,使上链接用户的传输功能和STAR-RIS的阶段性变换。尽管WSR优化是非convex的,但建议一种高效的迭接程序,以实现一个最优化问题的次最佳解决方案。第二,STAR-RIS的阶段变换将优化成一个优化问题,共同优化BS的波形和混合矢量的功能,使上链接用户的传输能力受到最大程度的限制,以及STAR-RIS的阶段变换。尽管WSR优化是非convex的,但建议一种高效的迭接程序是为了实现最优化问题的次最佳解决方案。第二,STAR-RIS的阶段变换将最终通过S-TRA的最新结果解释S-S-al IML的完整版本。