Achievable Rate Analysis of Intelligent Omni-Surface Assisted NOMA Holographic MIMO Systems
Qingchao Li, Mohammed El‐Hajjar, Yanshi Sun, Ibrahim Hemadeh, Yingming Tsai, Arman Shojaeifard, Lajos Hanzo
Abstract
An intelligent omni-surface (IOS) assisted holographic multiple-input and multiple-output architecture is conceived for <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$360^\circ$</tex-math></inline-formula> full-space coverage at a low energy consumption. The theoretical ergodic rate lower bound of our non-orthogonal multiple access (NOMA) scheme is derived based on the moment matching approximation method, while considering the signal distortion at transceivers imposed by hardware impairments (HWIs). Furthermore, the asymptotically ergodic rate lower bound is derived both for an infinite number of IOS elements and for continuous aperture surfaces. Both the theoretical analysis and the simulation results show that the achievable rate of the NOMA scheme is higher than that of its orthogonal multiple access counterpart. Furthermore, owing to the HWIs at the transceivers, the achievable rate saturates at high signal-to-noise ratio region, instead of reaching its theoretical maximum.