Ultra-narrowband for energy-scavenging-powered wireless sensor networks

Industrial and consumer applications, such as smart energy and e-wearables, have become a reality — thanks to the Internet of Things and wireless sensor networks — creating a billions-worth market. Very-large-scale integration combined with energy scavenging give a promising ultra-low-power, cost-effective, and environment-friendly solution for the increasing power consumption demands as tens of millions of nodes are deployed worldwide every year. Most available wireless standards are power-hungry and, therefore, not suitable for energy scavenging. In this paper, we motivate ultranarrowband as an energy-scavenging-compatible wireless technology for low-throughput wireless sensor networks (WSNs). The ultra-narrowband approach is energy-efficient for two case scenarios. The first one is for WSNs with a large coverage area. The second case scenario is where WSN nodes experience a high level of interference from other co-existing communication systems. Two practical use cases are studied numerically, one for each case scenario. In both cases, on a node level, the link is significantly imbalanced between the transmitting and receiving sections in terms of energy consumption and data rate. However, in case of an interference-rich environment, the radiated power from the WSN base station as well as the WSN nodes is preferred to be as low as possible, thus leading to a more balanced link.