Robust Beamforming Design for IRS-Assisted Downlink Multi-User MISO-URLLC in an IIoT Scenario

Intelligent reflecting surfaces (IRS) have recently been regarded as having potential for supporting multi-user (MU) multiple-input single-output (MISO) ultra-reliable and low-latency communication (URLLC) by creating favorable wireless links in the industrial IoT (IIoT) scenario. Hence, we studied joint robust design of a beamformer at central controller (CC) phase shifters IRS minimizing transmit power consumption based on perfect channel state information (CSI) imperfect CSI, respectively. The was formulated non-convex optimization problem, also taking into account quality-of-service (QoS) demands actuator, unit-modulus constraints IRS, robustness against impact CSI imperfection. Subsequently, proposed computationally efficient iterative algorithm to obtain suboptimal solution exploiting penalty method successive convex approximation (SCA) while method, S-procedure, SCA were adopted CSI. Finally, our simulation results revealed that (1) required URLLC significantly reduced employing instead conventional without IRS; (2) effective beamforming design.