In this letter, we investigate joint application of intelligent reflecting surface (IRS) and vertical beamforming in cognitive radio networks (CRN). After properly modeling the network, an optimization problem is formed to jointly design the beamforming vector and tilt angle at the secondary base station (BS) as well as the phase shifts at the IRS with the objective of maximizing spectral efficiency of the secondary network. The optimization problem is non-convex; thus, we propose an efficient solution method for it. Numerical results show that adding an IRS and optimizing the radiation orientation, can significantly improve performance of the CRNs.

中文翻译：

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智能反射表面辅助认知无线电网络中的垂直波束形成


在这封信中，我们研究了智能反射表面（IRS）和垂直波束成形在认知无线电网络（CRN）中的联合应用。在对网络进行正确建模后，形成一个优化问题，以联合设计辅助基站（BS）处的波束成形矢量和倾斜角以及IRS处的相移，以最大化辅助网络的频谱效率。优化问题是非凸的；因此，我们提出了一种有效的解决方法。数值结果表明，添加 IRS 并优化辐射方向可以显着提高 CRN 的性能。