标题： 联合功率控制与无源波束成形在IRS辅助的频谱共享中 显示英文标题

标题： Joint Power Control and Passive Beamforming in IRS-Assisted Spectrum Sharing

摘要： 在认知无线电（CR）通信系统中，在存在与主用户（PU）强交叉链路干扰的情况下实现高次用户（SU）速率是具有挑战性的。在本文中，我们利用新兴的智能反射表面（IRS）技术来解决这个问题。具体而言，我们研究了一个由IRS辅助的认知无线电通信系统，其中部署了一个IRS来协助主用户链路和次用户链路之间的频谱共享。我们旨在通过联合优化次用户发射功率和IRS反射波束成形，以最大化可实现的SU速率，同时满足PU链路给定的信干噪比目标。由于该公式化问题由于其非凸性和耦合变量而难以求解，我们提出了一种基于交替优化和连续凸逼近技术的高效算法来次优地解决它，并提出了一些启发式设计以降低复杂度。仿真结果表明，即使在传统CR系统中被认为最具挑战性的场景下，IRS也能够显著提高SU速率。 显示英文摘要

摘要： In cognitive radio (CR) communication systems, achieving high secondary user (SU) rate in the presence of strong cross-link interference with the primary user (PU) is challenging. In this letter, we exploit the emerging intelligent reflecting surface (IRS) technology to tackle this problem. Specifically, we investigate an IRS-assisted CR communication system where an IRS is deployed to assist in the spectrum sharing between a PU link and an SU link. We aim to maximize the achievable SU rate subject to a given signal-to-interference-plus-noise ratio target for the PU link, by jointly optimizing the SU transmit power and IRS reflect beamforming. Since the formulated problem is difficult to solve due to its non-convexity and coupled variables, we propose an efficient algorithm based on alternating optimization and successive convex approximation techniques to solve it sub-optimally, along with some heuristic designs for lower complexity. Simulation results show that IRS is able to significantly improve the SU rate, even for the scenarios deemed most challenging in conventional CR systems without using IRS.