1. [1] Ericsson: “NB-IoT: a sustainable technology for connecting billions of devices” (2016).
2. [2] Huawei: “NB-IoT -- Enabling new business opportunities” (2015).
3. [3] R. Ratasuk, et al.: “NB-IoT system for M2M communication,” IEEE Wireless Communnication and Networking Conference Workshops (2016) 428 (DOI: 10.1109/WCNCW.2016.7552737).
4. [4] J.-P. Bardyn, et al.: “IoT: the era of LPWAN is starting now,” 42nd European Solid-State Circuits Conference (2016) 25 (DOI: 10.1109/ESSCIRC.2016.7598235).
5. [5] M. Chen, et al.: “Narrow band internet of things,” IEEE Access 5 (2017) 20557 (DOI: 10.1109/ACCESS.2017.2751586).