Sum Rate Maximization for Multiuser MISO Downlink with Intelligent Reflecting Surface

Understand

The intelligent reflecting surface (IRS) is a planar array with massive reconfigurable passive elements, which can align the reflecting signals at the receivers via controlling the phase shifts at each element independently.

• Since IRS can be implemented without RF chain, it is seen as a cost-effective solution for boosting the spectral efficiency for the future communication system.
• This work considers the IRS-aided multiuser multi-input single-output downlink transmission, and our goal is to maximize the sum rate by jointly optimizing the transmit beamformer at the base station and the phase shifts, which can be either continuous or discrete, at the IRS.
• This sum rate maximization (SRM) problem is challenging, especially for the discrete-phase case.