Energy Efficiency (EE) is a significant problem for Cognitive Radio (CR) network. Recently,
more interest has focused on EE optimization problem in wireless-powered communication …

In this paper, we study resource allocation problems for a two-tier cognitive heterogeneous
network in interweave spectrum sharing mode. Secondary users (SUs) in small cells (SCs) …

Non-orthogonal multiple-access (NOMA) with perfect successive interference cancellation is
an emerging research topic in the future wireless communication systems. In this work …

Serving multiple cell-edge mobile terminals poses multifaceted challenges due to the
increased transmission power and interferences, which could be overcome by relay …

In this paper, we develop an optimization framework for the symbiotic operation of a
multiuser cognitive radio network (CRN) consisting of a non-orthogonal multiple access …

In this article, we investigate a selective decode-and-forward (DF)-aided cooperative
nonorthogonal multiple access (NOMA) system performance in the presence of practical …

In this paper, we study radio frequency (RF)-powered underlay cognitive radio networks
(CRNs) with power-domain non-orthogonal multiple access (NOMA). In these networks, by …

This paper considers a multiple-input multiple-output (MIMO) non-orthogonal multiple
access (NOMA) cognitive radio (CR) system with an unmanned aerial vehicle relay (UR). In …

Nonorthogonal multiple access (NOMA) represents a paradigm shift from conventional
orthogonal multiple-access (MA) concepts and has been recognized as one of the key …

In this letter, a novel reconfigurable intelligent surface (RIS)-and relay-assisted cooperative
network with non-orthogonal multiple access (NOMA) is proposed, where the line-of-sight …