Affiliation:
1. Key Laboratory of Modern Teaching Technology, Ministry of Education, Shaanxi Normal University, Xi’an 710062, China
2. School of Computer Science, Shaanxi Normal University, Xi’an 710062, China
Abstract
The recognition of human activity is crucial as the Internet of Things (IoT) progresses toward future smart homes. Wi-Fi-based motion-recognition stands out due to its non-contact nature and widespread applicability. However, the channel state information (CSI) related to human movement in indoor environments changes with the direction of movement, which poses challenges for existing Wi-Fi movement-recognition methods. These challenges include limited directions of movement that can be detected, short detection distances, and inaccurate feature extraction, all of which significantly constrain the wide-scale application of Wi-Fi action-recognition. To address this issue, we propose a direction-independent CSI fusion and sharing model named CSI-F, one which combines Convolutional Neural Networks (CNN) and Gated Recurrent Units (GRU). Specifically, we have introduced a series of signal-processing techniques that utilize antenna diversity to eliminate random phase shifts, thereby removing noise influences unrelated to motion information. Later, by amplifying the Doppler frequency shift effect through cyclic actions and generating a spectrogram, we further enhance the impact of actions on CSI. To demonstrate the effectiveness of this method, we conducted experiments on datasets collected in natural environments. We confirmed that the superposition of periodic actions on CSI can improve the accuracy of the process. CSI-F can achieve higher recognition accuracy compared with other methods and a monitoring coverage of up to 6 m.
Funder
National Natural Science Foundation of China
Excellent Graduate Training Program of Shaanxi Normal University
Subject
Electrical and Electronic Engineering,Biochemistry,Instrumentation,Atomic and Molecular Physics, and Optics,Analytical Chemistry
Reference30 articles.
1. Xu, C., Wang, W., Zhang, Y., Qin, J., Yu, S., and Zhang, Y. (2021). An Indoor Localization System Using Residual Learning with Channel State Information. Entropy, 23.
2. WiPasLoc: A Novel Passive Indoor Human Localization Method Based on WiFi;Wang;Comput. Sci.,2022
3. Long Short-Term Indoor Positioning System via Evolving Knowledge Transfer;Li;IEEE Trans. Wirel. Commun.,2022
4. WiFi-based indoor passive fall detection for medical Internet of Things;Xia;Comput. Electr. Eng.,2023
5. Mean Teacher-Based Cross-Domain Activity Recognition Using WiFi Signals;Xiao;IEEE Internet Things J.,2023