Prospects and Applications of Incoherent Light in Non-contact Wireless Sensing Systems

TL;DR

This paper explores the potential of incoherent visible and infrared light sources, like LEDs, for wireless sensing applications, highlighting their advantages over traditional RF and laser methods in various indoor and outdoor scenarios.

Contribution

It provides a comprehensive overview of the emerging use of incoherent light in wireless sensing, emphasizing its benefits and potential applications beyond current technologies.

Findings

Incoherent light offers energy-efficient, low-cost sensing options.

Applications include vehicle speed, vital signs, and structural health monitoring.

Incoherent light can outperform RF and laser in certain sensing tasks.

Abstract

The increasing demand for wireless sensing systems has led to the exploration of alternative technologies to overcome the spectrum scarcity of traditional approaches based on radio frequency (RF) waves or microwaves. Incoherent light sources such as light-emitting diodes (LED), paired with light sensors, have the potential to become an attractive option for wireless sensing due to their energy efficiency, longer lifespan, and lower cost. Although coherent light or laser may present safety risks to human eyes and skin, incoherent visible and infrared light has low intensity, and does not harm the human body. Incoherent light has the potential to supersede other wireless sensing technologies, namely RF, laser and camera, by providing many additional benefits including easy implementation, wide bandwidth, reusable frequency, minimum interference, enhanced privacy and simpler data processing. However, the application of incoherent light in the wireless sensing domain is still in its infancy and is an emerging research topic. This study explores the enormous potential and benefits of incoherent visible and infrared light in wireless sensing through various indoor and outdoor applications including speed estimation of vehicles, human vitals monitoring, blood glucose sensing, gesture recognition, occupancy estimation and structural health monitoring.