Outage Analysis of Millimeter Wave Assisted Full-Duplex Cooperative D2D communications System with Non-orthogonal Multiple Access

Abstract

Millimeter-wave (mmWave) assisted device-to-device (D2D) communications system has evolved as a promising technology for the fifth-generation (5G) and beyond cellular networks. The demand for ultra-high data rate and increased spectral efficiency has been an impetus for leveraging the benefits of mmWave assisted D2D communications. Hence, the integration of non-orthogonal multiple access (NOMA) and full-duplex (FD) communications with mmWave assisted D2D communications has become an essential part of 5G and beyond cellular networks to support the high capacity demand of emerging technologies. This paper proposes a mmWave assisted FD cooperative D2D (C-D2D) system utilizing the properties of NOMA, wherein a D2D transmitter (DT) acts as an FD relay which decodes the cellular uplink transmission and forwards the superimposed signal consisting of cellular as well as D2D user's data to D2D receiver (DR) and the base station (BS). The decoding of respective signals at the BS and DR is done utilizing the successive interference cancellation (SIC) property of NOMA. We have considered that each node is equipped with directional antennas capable of beamforming. Closed-form expressions of cellular and D2D outage probabilities have been derived and verified with the help of simulations. Results show the variation of cellular and D2D outage probabilities with respect to the various transmission distances and the power splitting factor (α), and an optimum value of α has been shown.