Performance Analysis of Narrowband Internet of Things (NB-IoT) Deployment Modes

The Internet of Things (IoT) devices are finding their way into nearly every aspect of modern day life, as a result, their applications are increasing exponentially. This increased demand and dependence on IoT devices has accelerated the evolution of various radio access technologies to cater for the networking needs of these resource-constrained devices. One of the recently evolved radio access technologies especially suited to the IoT applications, is the Narrowband IoT (NB-IoT). The NB-IoT has been developed for narrowband and Low Power Wide Area Networks (LPWANs) with the focus primarily on deep indoor coverage enhancement, support for low network throughput, delay insensitivity, low power consumption, low manufacturing cost and a massive number of connections per cell. The NB-IoT is very closely related to the existing cellular technologies yet it has an identity of its own. The NB-IoT is still under development and is undergoing fresh real-time and simulation-based analyses. For the performance evaluation of NB-IoT, only a few proprietary test-benches are currently available. Other open source simulators either lack the NB-IoT functionalities entirely or require intense modification in the existing LTE based models and functions. In this paper, we present the results of the performance evaluation of NB-IoT in different deployment modes and link budget scenarios. The performance indicators used for the evaluation are also studied in detail using a non-proprietary simulation tool to ascertain NB-IoT performance and reliability. Our results show that the Block Error Rate (BLER) improves at a cost of latency. Also, the guard-band and the single-tone transmission modes gives optimal performance.