A Cooperative SWIPT-Hybrid-NOMA Pairing Scheme considering SIC imperfection for THz Communications

Abstract

Almost all the sixth-generation (6G) non-orthogonal multiple access (NOMA)-based research assumes a perfect successive interference cancelation (SIC) when it comes to system analysis or planning; this assumption should be supported by advanced schemes that consider the suggested technologies and THz characteristics. The work in this paper proposes an optimized two-user pairing scheme where simultaneous wireless information and power transfer (SWIPT) is adopted with cooperative hybrid-NOMA (H-NOMA) in terahertz (THz) considering SIC imperfection. The aim is to improve the overall performance of wireless THz communication networks including wireless connectivity, resource management, scalability, and user fairness. Hence, thorough studies for a number of SWIPT-NOMA schemes were presented alongside a selection of the best H-NOMA pairing strategy for the served users. We investigated system performance according to SIC manipulation to develop a proper SWIPT-based simplified system. The results showed a remarkable improvement in energy efficiency and spectral efficiency compared to conventional work (NOMA and OMA time division multiple access (TDMA)) by 75%. This promising proposal has a positive impact on reducing system hardware, complexity, and cost while improving signal detection, diversity, and reliability, without the need for complicated techniques such as multiple-input multiple-output (MIMO).