Incremental Relay Inspired Mode Selection for SWIPT-Enabled NOMA Systems with Imperfect SIC and Random User Locations

This paper proposes transmission mode switching for the simultaneous wireless information and power transfer enabled non-orthogonal multiple access (NOMA) systems with imperfect successive interference cancellation (SIC) and random user locations. The system is composed of a base station (BS) and multiple near and far users. The location of the near and far users follows a homogeneous Poisson point process. The near users adopt incremental relay protocol and the simultaneous wireless information and power transfer enabled system can switch between cooperative and non-cooperative transmission mode based on 1-bit feedback of the far users. Due to the decoding errors of practical SIC process, imperfect SIC is considered at the near user. Under the proposed mode switching scheme, the closed-form expressions for the outage probability and system throughput are obtained considering random user locations. Numerical results demonstrate the correctness of the theoretical analysis and show that the proposed scheme outperforms the traditional cooperative and non-cooperative NOMA schemes in terms of outage and throughput performance.