Outage Performance Analysis for SWIPT-Based Incremental Cooperative NOMA Networks With Non-Linear Harvester

This work studies a simultaneous wireless information and power transfer based downlink non-orthogonal multiple access (NOMA) network. The near user is equipped with a non-linear energy harvester, whose non-linear property is depicted by a piecewise linear model. An incremental cooperative NOMA (ICN) protocol is proposed to improve the performance of the considered network. Specifically, based on no more than 2-bit feedback from the far and near users, respectively, the network determines to work in the direct NOMA transmission (DNT), conventional point-to-point communications, or conventional cooperative NOMA (CCN) modes. The outage probabilities and throughput for both the far and near users are derived. Numerical results compare the differences among the proposed ICN, CCN, DNT and orthogonal multiple access protocols in terms of outage performance and system throughput, and exhibit the superior performance of the proposed ICN protocol.