FBL Driven Battery-Assisted Energy Harvesting Full-Duplex Cooperative NOMA With SIC and CSI Imperfections

This paper explores a cooperative non-orthogonal multiple access (NOMA) network that includes a multi-antenna base station (B), a nearby Internet-of-Thing (IoT) user (NU) with full-duplex capabilities, and several distant IoT users (FU). The NU employs a time-switching (TS) energy harvesting (EH) protocol, supplementing the harvested energy with a small amount from its battery to enhance the performance of FU. The study introduces a novel cooperative NOMA/non-cooperative (C-NM/NC) switching scheme, considering factors such as imperfect successive interference cancellation (SIC), channel state information (CSI) errors, and nonlinear EH. Closed-form expressions for average blocklength error rates (BLER) for both users are derived within the finite blocklength regime. These BLER expressions are used to analytically express key performance metrics such as goodput, reliability, latency, and energy efficiency (EE). The study emphasizes the significant performance degradation caused by CSI errors for both users. It is shown that the novel C-NM/NC switching allows FU to consistently achieve performance on par with the C-NM mode, even when meeting a specific NU throughput requirement. Maximizing FU goodput is demonstrated to be possible through careful adjustment of TS parameters and battery energy. Moreover, C-NM/NC switching not only enhances EE but also improves self-interference immunity. Monte Carlo simulations are performed to validate the accuracy of the analytical results.