Understanding the Impact of Environmental Conditions on Zero-Power Internet of Things: An Experimental Evaluation

The booming Internet of Things is transforming all industries, making them more productive and efficient. Unfortunately, with its widespread use, a series of challenges are posed by sustainable sensing, harsh working environments, laboursome battery replacement, and the requirement for an ultra-small form factor. The concept of zero-power Internet of Things has recently been proposed to overcome these challenges by integrating far-field wireless power transfer, ambient energy harvesting, and backscatter wireless communications into networked embedded systems. However, the development of far-field wireless power transfer is still in its infancy, and how environmental conditions affect its performance in the real world remains unclear. This article fills this gap and provides an extensive experimental study to quantify the impact of environmental conditions - line-of-sight propagation, multipath interference, building materials used, and non-air mediums - on far-field wireless power transfer. Inspired by this study, we further shed light on a few future research directions.