Performance Analysis of Ambient Backscatter Uplink NOMA Networks

Abstract

A core vision of the future sixth-generation wireless networks is to serve, in the most spectral and energy efficient way, a massive number of devices and/or Internet-of-Things (IoT) sensors, plenty of which are expected to be low-powered or even battery-free. In this direction, non-orthogonal multiple access (NOMA) and ambient backscatter communications (AmBC) are considered as two key promising technologies. In this work, we present a novel analytical framework for studying the performance of uplink NOMA-based AmBC systems. Specifically, analytical expressions for both NOMA-users' and IoT backscatter device's (BD) outage probabilities (OPs) are derived under both perfect and the more realistic case of imperfect successive interference cancellation (SIC). Likewise, system's performance at the high signal-to-noise ratio (SNR) regime is investigated as well as expressions for the system's overall average throughput are also derived. A performance comparison between the proposed setup and a conventional orthogonal multiple access (OMA)-based AmBC system is provided as well as it is proved that the proposed system's average throughput is equal or even greater compared to a conventional uplink NOMA system with two NOMA-users and no BDs.