Device-Free Activity Recognition for Underground Spaces Based on Convolutional Neural Network

  • Qizhen Zhou
  • Jianchun XingEmail author
  • Xuewei Zhang
  • Wei Chen
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 890)


Inspired by the excellent work of wireless sensing, we propose a non-invasive activity recognition system, Under-Sense, for underground space sensing with a pair of commodity Wi-Fi devices. Firstly, by extracting relative phase information from all 90 subcarriers, we construct fine-grained images and then compress the rectangle images into k-dimension by singular value decomposition (SVD). A nine-layer convolutional neural network (CNN) is designed to automatically extract important features from constructed images and classify five human activities. Our results show Under-Sense could achieve 99.5% average accuracy in the empty meeting room and 96.7% in complex student studio environment.


Smart underground space Wi-Fi-based sensing Activity recognition Convolutional neural network 


Acknowledgements, Ethical Approval and Informed Consent

This work is supported by the National Key Research and Development Project of China No. 2017YFC0704100 (entitled New Generation Intelligent Building Platform Techniques).

This study has been conducted with ethics approval obtained from the ethics committee: Prof. Qiliang Yang and Prof. Ping Wang of Department of National Defense Engineering, Army Engineering University of PLA, Jiangsu, China.

Participants are recruited from Army Engineering University of PLA, Jiangsu, China, and all participants have given their consent to use the dataset and disclose information relevant for research in this study.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Qizhen Zhou
    • 1
  • Jianchun Xing
    • 1
    Email author
  • Xuewei Zhang
    • 1
  • Wei Chen
    • 1
  1. 1.Army Engineering University of PLAJiangsuChina

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