TY - EJOU AU - Lu, Zhiping AU - Yue, Xinwei AU - Chen, Shuo AU - Ma, Weiguo TI - Outage Behaviors of Active Intelligent Reflecting Surface Enabled NOMA Communications T2 - Computer Modeling in Engineering \& Sciences PY - 2023 VL - 137 IS - 1 SN - 1526-1506 AB - Active intelligent reflecting surface (IRS) is a novel and promising technology that is able to overcome the multiplicative fading introduced by passive IRS. In this paper, we consider the application of active IRS to non-orthogonal multiple access (NOMA) networks, where the incident signals are amplified actively through integrating amplifier to reflecting elements. More specifically, the performance of active/passive IRS-NOMA networks is investigated over large and small-scale fading channels. Aiming to characterize the performance of active IRS-NOMA networks, the exact and asymptotic expressions of outage probability for a couple of users, i.e., near-end user and far-end user are derived by exploiting a 1-bit coding scheme. Based on approximated analyses, the diversity orders of user and user are obtained for active IRS-NOMA. In addition, the system throughput of active IRS-NOMA is discussed in the delay-sensitive transmission. The simulation results are carried out to verify that: i) The outage behaviors of active IRS-NOMA networks are superior to that of passive IRS-NOMA networks; ii) As the reflection amplitude factors increase, the active IRS-NOMA networks are capable of furnishing the enhanced outage performance; and iii) The active IRS-NOMA has a larger system throughput than passive IRS-NOMA and conventional communications. KW - Active intelligent reflecting surface; amplification noise; non-orthogonal multiple access; outage probability DO - 10.32604/cmes.2023.027663