In this work, we characterize the outage probability (OP) of an intelligent reflecting surface (IRS) assisted multi-user multiple-input-single-output (MU-MISO) communication system. Using a two-step approximation method, we approximate the signal-to-interference-plus-noise ratio (SINR) for any downlink user by a Log-Normal random variable. The impact of various system parameters is studied using the closed-form expression of OP. It is concluded that the position of IRS has a critical role, but an appropriate increase in the number of IRS elements would help to compensate for the loss in performance if the position of IRS is suboptimal.

翻译：在这项工作中,我们将智能反射表面(IRS)辅助多用户多投入单产出(MU-MISO)通信系统的失灵概率(OP)定性为智能反射表面(IRS)辅助多用户多投入单产出(MU-MISO)通信系统。使用两步近似法,我们用一个日志-热随机变量对任何下行用户的信号对干涉加噪音比率(SINR)进行近似。利用OP的封闭式表达方式研究各种系统参数的影响。我们的结论是,IRS的位置具有关键作用,但如果IRS的位置不理想,则适当增加IRS元素的数量将有助于弥补性能损失。