Intelligent Reflecting Surface: Practical Phase Shift Model and Beamforming Optimization

@article{Abeywickrama2020IntelligentRS,
  title={Intelligent Reflecting Surface: Practical Phase Shift Model and Beamforming Optimization},
  author={Samith Abeywickrama and Rui Zhang and Qingqing Wu and Chau Yuen},
  journal={IEEE Transactions on Communications},
  year={2020},
  volume={68},
  pages={5849-5863}
}
Intelligent reflecting surface (IRS) that enables the control of the wireless propagation environment has been looked upon as a promising technology for boosting the spectrum and energy efficiency in future wireless communication systems. [] Key Method The formulated problem is non-convex and difficult to be optimally solved in general, for which we propose a low-complexity suboptimal solution based on the alternating optimization (AO) technique. Simulation results unveil a substantial performance gain…

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A practical phase shift model is proposed that captures the phase-dependent amplitude variation in the element-wise reflection coefficient and is applied to an IRS-aided wireless system to maximize its achievable rate.
Beamforming Optimization for Intelligent Reflecting Surface with Discrete Phase Shifts
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A practical transmission protocol to execute channel estimation and reflection optimization successively for an IRS-enhanced orthogonal frequency division multiplexing (OFDM) system is proposed.
Joint Active and Passive Beamforming Optimization for Intelligent Reflecting Surface Assisted SWIPT Under QoS Constraints
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