NB-IoT: BLER and Throughput Analysis in Downlink Physical Shared Channel

Abstract

Internet of Things (IoT) specifies a network of connected physical objects that are equipped with sensors, processing components, software and transceivers to exchange data in real time over the internet. IoT consists of mechanical and digital machines and may contain real time health monitoring data for remote connectivity and processing. The IoT devices are considerably constrained by resources with an imperative reduction in power consumption, processing speed and computation. To support the various requirements of IoT, various low-power radio communication technologies are developed recently. Narrow Band IoT (NB-IoT) is a cutting edge low-power wide area network (LPWAN) wireless communication technology and part of 5G regime that is standardized in 3GPP release 13. Additionally, NB-IoT and LTE share a number of common features that enables NB-IoT to share the same infrastructure as LTE. NB-IoT supports a high-density communication with an increase in the coverage. NB-IoT is a promising technology that has gained considerable research interest recently. Additionally, NB-IoT is implemented in various novel fields with smart cities, smart inventory management, smart agriculture being a few prominent applications. Although, 3GPP release 13 standardizes the NB-IoT features, it remains an open research problem to analyze the performance of NB-IoT under various channel and signaling conditions. In the current work, the features of NB-IoT including the deployment modes are discussed. Additionally, the channels and signals of NB-IoT are summarized and discussed. Further, extensive simulations are performed to determine the Block Error Rate (BLER) and throughput of Narrow-Band Physical Downlink Channel under different signaling conditions, Number of Repetitions (Nrep) and changed Transport Block Size (TBS). A reduction in BLER is noted with the increase in number of repetitions as well with increased SNR. The results are presented in a tabular form for better clarity and analyzed to identify the superior communication conditions in NB-IoT.