An Experimental Evaluation of Energy Trade-Offs in Narrowband IoT

Narrowband IoT is introduced to support cellular Internet of Things. Several features introduced in NB-IoT help to reduce the energy consumption of an IoT node. While older energy models typically rely on theoretical assumptions, we present an experimental evaluation of the NB-IoT energy consumption. By controlling the link quality and measuring the energy consumption in each modem state, we are able to establish a fine-grained energy profile of a NB-IoT module in a public telecommunications network. In this paper, we compare a theoretical model found in literature with the results of this real-life setup. Our measurements indicate a less optimistic power profile than proposed in the theoretical model. We also highlight the contribution of each of the Narrowband IoT (NB-IoT) defined modem states to the typical energy profile of an NB-IoT node. This allows for a more realistic model for energy simulations and for further optimization of the power efficiency of NB-IoT applications.