Modeling and Quantitative Analysis of Motion Detection in CSI-Based Sensing

Channel state information (CSI) based sensing approaches have unique advantages for fine-grained motion sensing. However, due to the mismatch between the sensing position and detection probability, mapping motion-sensing precision to optimal detection zones is an involved problem. In this letter, we propose a general CSI-based motion detection model, in which the Fresnel Zones and radar detection theory are used to analyze the key factors affecting detection probability. Besides, analytic expressions for the detection probability at arbitrary positions with available and unavailable phases are derived. Finally, numerical results corroborate the theoretical analysis and show that appropriate transceiver deployment and sensing frequency selection can effectively improve sensing performance.