Performance Analysis of Energy Harvesting-Assisted Overlay Cognitive NOMA Systems With Incremental Relaying

In this paper, we analyze the performance of an energy harvesting (EH)-assisted overlay cognitive non-orthogonal multiple access (NOMA) system. The underlying system consists a primary transmitter-receiver pair accompanied by energy-constrained secondary transmitter (ST) with its intended receiver. Accordingly, ST employs time switching (TS) based receiver architecture to harvest from radio-frequency signals transmissions, and thereby uses relay information transmit own simultaneously using NOMA principle. For this, propose two cooperative spectrum sharing (CSS) schemes on incremental relaying (IR) protocol amplify-and-forward (AF) decode-and-forward (DF) strategies, viz., CSS-IAF CSS-IDF, compare their competitive fixed schemes. proposed IR-based adeptly avail degrees-of-freedom boost performance. Thereby, considering realistic assumption NOMA-based imperfect successive interference cancellation, derive expressions outage probability for networks under both CSS-IDF subject Nakagami-m fading. addition, quantify throughput efficiency considered obtained theoretical findings are finally validated through numerous analytical simulation results reveal advantages CSS over baseline direct link transmission orthogonal