@inbook{d2646d45a04146169956a2552c3b8a9f,
title = "Fresnel Zone Based Theories for Contactless Sensing",
abstract = "Contactless sensing utilizes pervasive wireless signals (e.g., Wi-Fi, 4G/5G) to sense the context information of human targets. It achieves non-intrusive human sensing without requiring the targets to wear any sensors. Contactless wireless sensing has enabled a large range of applications including gesture recognition, activity identification, and vital sign monitoring. To analyze the sensing performance and guide the system design, theoretical models which can help people understand the underlying mechanisms are critical. In this chapter, we introduce the Fresnel Zone based theories for contactless sensing leveraging signal propagation models in the air. The sensing theories consist of reflection model and diffraction model. These two models respectively characterize the relationship between the target movements and corresponding signal variations when the target is located near to and far away from the wireless transceivers. These models also help people understand the effect of target location and orientation with respect to the wireless transceivers on sensing performance. Therefore, the Fresnel Zone-based sensing theories lay the theoretical foundations for the design and analysis of wireless sensing systems.",
keywords = "Contactless sensing, Diffraction model, Fresnel Zone based theories, LTE sensing, Reflection model, Respiration monitoring, Wi-Fi sensing, Wireless sensing",
author = "Daqing Zhang and Fusang Zhang and Dan Wu and Jie Xiong and Kai Niu",
note = "Publisher Copyright: {\textcopyright} 2021, Springer Nature Switzerland AG.",
year = "2021",
month = jan,
day = "1",
doi = "10.1007/978-3-030-68590-4\_5",
language = "English",
series = "Intelligent Systems Reference Library",
publisher = "Springer Science and Business Media Deutschland GmbH",
pages = "145--164",
booktitle = "Intelligent Systems Reference Library",
}