Performance of Narrowband IoT Link Adaptation with Rate and Energy Objectives

This paper provides a detailed investigation on the performance of Narrowband IoT link adaptation under different approaches: Max-Rate approach, Min-Energy approach and the Max-Energy-Efficiency approach while considering realistic channel estimation. Simulation results study the impact of the received power on the performance of the link adaptation in terms of the achieved consumed energy, data rate, energy efficiency, and spectral efficiency. Particularly, we show that maximizing data rate in NB-IoT leads to maximizing the spectral efficiency except at extremely low received powers. Also, results focus on the impact of the data size on the performance of the link adaptation in NB-IoT. We show that larger data sizes lead to higher energy consumption, lower data rate and lower energy efficiency.