Resource Allocation for the 4G and 5G Dual-Connectivity Network with NOMA and NR

3GPP has defined Dual Connectivity (DC) to allow a user to access a 4G and a 5G base station (BS) simultaneously. However, the resource allocation for DC is challenging because of not only the co-channel interference between 4G and 5G BSs but also different shapes of Resource Blocks (RBs) for New Radio (NR) and the reuse of RBs for Non-Orthogonal Multiple Access (NOMA). In this paper, we formulate Dual Connectivity Multidimensional Resource Allocation Problem and prove that it is NP-hard. We design an approximation algorithm with the ideas of 1) Zone Shaping, 2) Occupancy Indicator and Overlap Degree of RBs, 3) DC Slicing, and 4) DC Inter-Numerology Relation, to maximize the total throughput of heterogeneous user demands in the coexisting 4G and 5G network with NR, NOMA, and DC. Simulation results manifest that our algorithm outperforms the state-of-the-arts regarding throughput and resource efficiency.