An intelligent reflecting surface (IRS) can greatly improve the channel quality over a frequency-flat channel, if it is configured to reflect the incident signal as a beam towards the receiver. However, the fundamental limitations of the IRS technology become apparent over practical frequency-selective channels, where the same configuration must be used over the entire bandwidth. In this paper, we consider a wideband orthogonal frequency-division multiplexing (OFDM) system that is supported by a fairly realistic IRS setup with two unbalanced states per element and also mutual coupling. We describe the simulation setup considered in the IEEE Signal Processing Cup 2021, propose a low-complexity solution for channel estimation and IRS configuration, and evaluate it on that setup.

翻译：智能反射表面( IRS) 能够大大改善频率膨胀频道的频道质量, 如果它被配置成能反映事件信号对接收器的波束。 但是, IRS 技术的基本局限性显然超过实际的频率选择性频道, 整个带宽必须使用同样的配置。 在本文中, 我们考虑一个宽带或分波频率多路转换( OFDM) 系统, 该系统得到一个相当现实的IRS 系统的支持, 该系统每个元素有两个不平衡的状态, 并且相互连接 。 我们描述在 IEEEE 信号处理杯 2021 中考虑的模拟设置, 提出频道估计和 IRS 配置的低兼容性解决方案, 并评估该设置 。