Green Dual Connectivity Selection Algorithm in 5G-NR/4G-LTE NSA HetNet

Dual connectivity (DC) can increase network capacity by allowing a user to simultaneously connect to more than one Radio Access Technology (RAT) at the same time. Although it offers higher network capacity, power management is a constraint in DC enabled heterogeneous networks (HetNet). This work aims to find the best trade-off between network capacity and power efficiency in DC deployed Fifth Generation New Radio (5G-NR) and Long Term Evolution (LTE) HetNet. Past works have not conducted a simultaneous optimization of power saving and capacity enhancement for DC in a Non Standalone(NSA) setup. A novel base station pairing technique is used to determine Next Generation Node B (gNB) sleep patterns. Two algorithms, the Super Greedy algorithm and the Integer Linear Programming (ILP) - Greedy algorithm are proposed to find the optimal way to preserve network power and enhance the user throughput. The ILP-Greedy uses ILP optimization for power minimizing through cell sleeping and a greedy algorithm for user association. Based on comparison with past baseline works, the ILP-Greedy algorithm is found to be superior for DC implementation in a 4G/5G NSA HetNet, saving 7.02 % of network power and still providing comparable network capacity improvement.