Cooperative NOMA in Multi-Content Multimedia Broadcasting

In this paper, we investigate an innovative scheme to provide high definition multi-content multimedia with extended coverage area based on cooperative non-orthogonal multiple access (NOMA). The broadcasters cooperatively share and transmit their multimedia over the same frequency band in a time division multiplexing (TDM) format. The data streams with two robustness levels are superimposed by a layered division multiplexer (LDM). This combined TDM/LDM model introduces a two-stage decoding process based on successive interference cancellation (SIC). Compared to the current single-content orthogonal methods employed in broadcast networks, our contribution is to enhance both the throughput and multicontent broadcasting coverage in a cooperative NOMA scheme. Our proposed scheme is based on the duality theorem of multiple access channels and broadcast channels capacity regions. We show that our scheme can improve the throughput by at least 40% compared to the orthogonal single content broadcasting. We further investigate the performance of the proposed technique in digital TV (DTV) broadcast channels based on ATSC 3.0, where we profit from the use of adaptive coding and modulation and LDM. The simulation results confirm the gains in coverage, efficiency, and throughput.