Energy Efficiency Maximization for Hybrid TDMA-NOMA System With Opportunistic Time Assignment

In this paper, we consider an energy efficient resource allocation technique for a hybrid time division multiple access (TDMA) - non-orthogonal (NOMA) system. such system, the available transmission is divided into several sub-time slots, and slot allocated to serve group of users (i.e., cluster). Furthermore, signals in each cluster are transmitted based on NOMA approach. With NOMA, can be served simultaneously through utilizing power domain multiplexing at transmitter successive interference cancellation (SIC) receiver. maximize efficiency (EE), jointly allocate both slots transmit TDMA-NOMA particular, formulate EE maximization (EE-Max) problem aiming overall system with per-user minimum rate constraints. However, joint optimization non-convex nature, thus, cannot solved directly. Therefore, develop iterative algorithm by approximating original convex one sequential approximation (SCA) novel second-order cone (SOC) Simulation results demonstrate that performance proposed outperforms equal terms EE. further confirm approaches SCA SOC techniques converge within few number iterations while yielding solution problem.