Communication Enhancement Model of Intelligent Reflecting Surface Based on Cooperative Relationship

Intelligent reflecting surface (IRS) is a plane that integrates a large number of low-cost, low loss, reconfigurable passive reflectors. It could intelligently configure signal propagation and improve the spectrum efficiency and energy efficiency of wireless network. Specifically, after the position of the user is known, the reflected phase of the signal is calculated by using the optimization algorithm to enhance the power received by the user. This paper proposes a dual IRS model with cooperative relationship in indoor small-scale environment, which uses two IRSs with cooperative relationship to enhance the signal power received by the user when the direct link between the base station and the user is unavailable. The phase shift matrixes of the two IRS are used as the optimization variables to maximize the signal power received by the user. The problem is a nonconvex network optimization problem, which is solved by solver based on interior point optimization, and compared with the model without cooperation at the same time. The comparison results show that the model with cooperation relationship has a better enhancement effect than the model without cooperation relationship in small-scale environment.