A Heterogeneous Network Transmission Architecture Based on NOMA for Next-Generation Converged Communications and Broadcasting Systems

Inter-Tower Communication Network (ITCN), which supports communication between different base stations via wireless links, has excellent potential for simultaneous transmission of broadcast data and personalized data using Layered Division Multiplexing (LDM). In this paper, a heterogeneous ITCN architecture using LDM and wireless backhauling is proposed. In uplink transmission, the power-limited user devices transmit data to the secondary transmitters (STs), and the STs relay the data to the master transmitter (MT). In downlink transmission, the MT and multiple STs cooperatively transmit broadcast data using single frequency network (SFN) mode, and the STs relay the personalized data from the MT to users simultaneously. Considering the co-channel interference, this paper proposes a joint subchannel assignment and power allocation scheme for both uplink and downlink transmission. A mixed integer optimization problem is formulated, and an alternating optimization algorithm (AO) based on game theory and convex optimization is proposed. Simulation results are conducted with different system configurations to demonstrate the convergence and effectiveness of the proposed algorithms.