Noise‐Robust Optimization of Impedance Loading for Single‐RF MIMO Systems

Abstract

Multiple‐Input‐Multiple‐Output (MIMO) systems are widely used to enhance the system capacity in wireless communications systems. The complexity and the cost for implementing the multiple radio frequency‐chain (RF‐chain) increases proportional to the number of signal streams. Therefore, so‐called load modulating single‐RF MIMO system is one promising technology in the practical aspects. Load modulating single‐RF MIMO can utilize two‐port network for controlling the load and the desired signal can be generate by loading proper set of impedance. In this paper, the optimization method for choosing the two‐port network impedance solution that is robust to the impedance noise is proposed and the simulations are conducted to verify the robustness. © 2023 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.