论文标题
智能反射表面辅助D2D底层通信的两次计算优化
Two-Timescale Optimization for Intelligent Reflecting Surface Aided D2D Underlay Communication
论文作者
论文摘要
设备对设备（D2D）底层通信系统的性能受到蜂窝用户（CUS）和D2D设备之间的共通道干扰的限制。为了应对这一挑战，本文研究了智能反射表面（IRS）辅助D2D底层系统。提出了一个两次尺度优化方案，以减少所需的渠道训练和反馈开销，在该方案中，在基本站（BS）发射光束（BS）和D2D发射器的功率控制适用于瞬时有效的通道状态信息（CSI）； IRS相移适应缓慢变化的通道平均值。基于两次计算优化方案，我们旨在最大化D2D Ergodic速率，而受到CU的限制性概率约束信噪比（SINR）目标。两个时间尺度的问题被解耦到两个子问题，并用封闭形式的表达式迭代解决两个子问题。数值结果验证了基于两个计算的优化的性能比几个基线的表现更好，并且还表现出了系统性能和CSI开销之间的良好权衡。
The performance of a device-to-device (D2D) underlay communication system is limited by the co-channel interference between cellular users (CUs) and D2D devices. To address this challenge, an intelligent reflecting surface (IRS) aided D2D underlay system is studied in this paper. A two-timescale optimization scheme is proposed to reduce the required channel training and feedback overhead, where transmit beamforming at the base station (BS) and power control at the D2D transmitter are adapted to instantaneous effective channel state information (CSI); and the IRS phase shifts are adapted to slow-varying channel mean. Based on the two-timescale optimization scheme, we aim to maximize the D2D ergodic rate subject to a given outage probability constrained signal-to-interference-plus-noise ratio (SINR) target for the CU. The two-timescale problem is decoupled into two sub-problems, and the two sub-problems are solved iteratively with closed-form expressions. Numerical results verify that the two-timescale based optimization performs better than several baselines, and also demonstrate a favorable trade-off between system performance and CSI overhead.
