Ring-based Intelligent Reflecting Surface Placement for 5G and Beyond

The Intelligent Reflecting Surface (IRS) is an emerging technology in mobile communication networks. It is regarded as a potential solution for the path fading problem and obstacle issue while using millimeter wave communications. Most existing researches focus on deploying few IRSs within the coverage of a macrocell. In the paper, the deployment problem of multiple macro cells and IRSs is considered. The Macrocell-first and IRS-first algorithms are proposed, and the Ring-based algorithm is further proposed to achieve the highest average utility rate of all served users. It divides a macrocell's coverage into $K$ rings, and deploys IRSs from outer ring to inner ring. Simulation-based results showed that the proposed Ring-based algorithm is superior to the Macrocell-first and IRS-first algorithms in terms of higher average utility rate with slightly fewer number of served users.