Beamspace MIMO-NOMA for Millimeter-Wave Broadcasting via Full-Duplex D2D Communications

In order to meet the tremendous requirements on the convergence between broadband and broadcast, this paper proposes to incorporate layered division multiplexing (LDM), an important variant of non-orthogonal multiple access (NOMA) technologies, into Millimeter wave (mmWave) multiple-input multiple-output (MIMO) system with device-to-device (D2D) communications to simultaneously provide broadcast and unicast services. The performance of the proposed full-duplex D2D-aided mmWave MIMO-NOMA with randomly deployed users is then analyzed under practical assumptions. Closed-form expressions of both the outage probability and the ergodic capacity are then derived by using the Laplace transform technique. Finally, detailed numerical results reveal the performance gains of the proposed scheme compared with the LDM without D2D communications and conventional time division multiplexing based scheme. The impacts of the antenna array gain and the transmission power of both the base station and the full-duplex link on system performance are also presented. Besides, we observe that it is vital to optimal the transmission power of the full-duplex link which ensures less self-interference to enhance the system capacity.