Design and Performance of Unlicensed NB-IoT

Due to the characteristics of wide coverage and low power consumption, the Narrow Band Internet of Things (NB-IoT) is believed to be a promising candidate technology to enable massive IoT in the upcoming 5G. Generally, the cellular NB-IoT is deployed only in licensed spectrum which is expensive and resource-constrained, thus causing limitations for operators. In view of these challenges, it is envisioned to opportunely operate NB-IoT in unlicensed spectrum, also termed as NB-IoT-U. In this paper, we present a specific framework for NB-IoT-U system with the restriction from the Federal Communications Commission (FCC) regulations, in the Sub-1GHz band. To verify the feasibility of this technology, we provide a comprehensive performance analysis of NB-IoT-U in terms of coverage and battery life.