Energy and coverage study of LPWAN schemes for Industry 4.0

Low-Power Wide-Area Networks (LPWANs) are becoming one of the main building blocks for the Industrial IoT (IIoT) ecosystem, being an alternative to 2G/3G/4G cellular networks where long-range communication at very low speed is needed by battery powered sensors spread around the factory. Among the most promising approaches, SIGFOX stands out as an ultra-narrow band technology that allows similar signal coverage to that of cellular networks at one thousandth of its power requirements. In this paper, we analyze a SIGFOX-based heterogeneous network architecture, based on combining an ultra-low-power star network topology for short distance communications and SIGFOX as Internet Gateway for the low-power devices. By following this approach, clusters of IIoT devices are able to communicate with a nearby SIGFOX Gateway that reports the sensed data to the Internet. Extensive experimentation and energy modeling has been performed. In particular, it is found that an IoT sensor is able to autonomously operate during remarkably long periods of time, reaching up to 4 years when operating at a duty cycle of 60 minutes and powered by a 1 Ah battery.