Combining FD‐UAV and NOMA technologies in IoT sensor network with millimeter‐wave communications

Abstract

SummaryIn this article, we exploit the huge advantages of full‐duplex (FD) transmission, nonorthogonal multiple access (NOMA) technique, unmanned aerial vehicle (UAV), and millimeter‐wave (mmWave) communications in an Internet of things (IoT) sensor network. Specifically, the UAV operates as a FD amplify‐and‐forward (AF) relay to aid communications between an IoT sensor and multiple NOMA users. Moreover, the FD‐UAV (FDU) adopts both fixed and variable gains. We obtain exact expressions of outage probability (OP) and throughput of IoT‐FDU‐NOMA‐mmWave network with fixed and variable gains at FDU over Nakagami‐ fading channels. Numerical illustrations clearly show that the OP and throughput performance of the IoT‐FDU‐NOMA‐mmWave network with variable gain are considerably higher than those with fixed gain. Since mmWave bands are used, the OP and throughput of the IoT‐FDU‐NOMA‐mmWave network are greatly affected by carrier frequency and communication distances. Consequently, when the carrier frequency or/and the distances between the IoT sensor and the users increase, the transmit power of the IoT sensor and the FDU should be increased to maintain the network performance. On the other hand, the effects of residual loop interference (LI) induced by FD transmission are remarkable. Thus, more efforts to reduce the residual LI power have to be continuously performed. Moreover, the specific impacts of the key parameters such as fading order , the positions of the FDU, and data rates are clarified. More importantly, in practice, according to the fixed gain or the variable gain that is used, we can locate the position of FDU to achieve the best performance for the IoT‐FDU‐NOMA‐mmWave network.