Estimating Respiratory Rate Using Wi-Fi CSI Data Compared to Commercial Device Measurements

• Fábio G. Queirós UFF
• Julio C. H. Soto UFF
• Iandra Galdino UFF
• Carla E. C. Silva UFF
• Arthur Viana UFF
• Leticia de Oliveira UFF
• Célio Albuquerque UFF
• Débora C. Muchaluat-Saade UFF

DOI: https://doi.org/10.5753/sbcas.2025.7821

Abstract

Technological advancements have driven the development of various devices capable of estimating vital signs, such as respiratory rate. Despite the availability of these devices, they still present disadvantages, such as the discomfort generated during respiratory rate estimation due to the need for physical contact with the patient. In this context, Channel State Information (CSI) technology has emerged as a promising alternative. It allows the monitoring of Wi-Fi signals, which contain information about the transmission state, to estimate the breathing rate in home and hospital environments. In this work, we present the application of CSI, along with signal processing techniques, for estimating the respiratory rate in individuals. To validate our approach, we compared the respiratory rate estimates obtained with CSI to those of commercially validated devices, such as Polar H10 and Biopac. Our database consists of approximately 100 volunteers. The obtained results demonstrate a high similarity between the CSI estimates and those of the validated commercial devices.

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