Narrowband Internet of Things (NB-IoT) is gaining momentum as a promising technology for massive Machine Type Communication (mMTC). Given that its deployment is rapidly progressing worldwide, measurement campaigns and performance analyses are needed to better understand the system and move toward its enhancement. With this aim, this paper presents a large scale measurement campaign and empirical analysis of NB-IoT on operational networks, and discloses valuable insights in terms of deployment strategies and radio coverage performance. The reported results also serve as examples showing the potential usage of the collected dataset, which we make opensource along with a lightweight data visualization platform.
I. INTRODUCTIONAs part of beyond-4G and 5G systems, the machine type communication (MTC) paradigm provides the ideal substrate toward cellular internet of things (IoT), and is leading to a shift in cellular network design and deployment. On the one hand, MTC introduces a novel degree of heterogeneity, given that the things, i.e., autonomous devices with novel features and requirements, must be integrated into the mobile network, which was originally designed for serving humans with their peculiar traffic. On the other hand, it requires long term performance analyses for stable network deployment, in particular when its massive nature (mMTC), in terms of the unprecedented number of devices, is considered [1] [2].A relevant step toward enabling mMTC is represented by the 2016 Release 13 (Rel-13) standard by the 3rd generation partnership project (3GPP), where three technologies were proposed: Extended Coverage Global System for Mobile Communications (GSM) IoT (EC-GSM-IoT), Long Term Evolution (LTE) for MTC (LTE-M), and Narrowband IoT (NB-IoT) [2]. These represent the cellular options for so-called low power wide area networks (LPWANs), which aim to deliver massive IoT services over wide areas, i.e., several kilometers, with low costs and power consumption [3].Since Rel-13, and considering the advances in Rel-14 (2017) and Rel-15 (2018), NB-IoT is triggering significant attention across researchers and operators as one of the most appealing LPWANs [4] [5] [6]. Hence, the theoretical aspects of NB-IoT are being formalized and analyzed, while several mobile operators are launching and making operational NB-IoT networks worldwide [7].
