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See through walls with WiFi!

Published: 27 August 2013 Publication History

Abstract

Wi-Fi signals are typically information carriers between a transmitter and a receiver. In this paper, we show that Wi-Fi can also extend our senses, enabling us to see moving objects through walls and behind closed doors. In particular, we can use such signals to identify the number of people in a closed room and their relative locations. We can also identify simple gestures made behind a wall, and combine a sequence of gestures to communicate messages to a wireless receiver without carrying any transmitting device. The paper introduces two main innovations. First, it shows how one can use MIMO interference nulling to eliminate reflections off static objects and focus the receiver on a moving target. Second, it shows how one can track a human by treating the motion of a human body as an antenna array and tracking the resulting RF beam. We demonstrate the validity of our design by building it into USRP software radios and testing it in office buildings.

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    Published In

    cover image ACM Conferences
    SIGCOMM '13: Proceedings of the ACM SIGCOMM 2013 conference on SIGCOMM
    August 2013
    580 pages
    ISBN:9781450320566
    DOI:10.1145/2486001
    • cover image ACM SIGCOMM Computer Communication Review
      ACM SIGCOMM Computer Communication Review  Volume 43, Issue 4
      October 2013
      595 pages
      ISSN:0146-4833
      DOI:10.1145/2534169
      Issue’s Table of Contents
    Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected].

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    Publication History

    Published: 27 August 2013

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    Author Tags

    1. gesture-based user interface
    2. mimo
    3. seeing through walls
    4. wireless

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    SIGCOMM'13
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    SIGCOMM'13: ACM SIGCOMM 2013 Conference
    August 12 - 16, 2013
    Hong Kong, China

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    SIGCOMM '13 Paper Acceptance Rate 38 of 246 submissions, 15%;
    Overall Acceptance Rate 462 of 3,389 submissions, 14%

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    • (2025)Efficient Deep Learning-Based Device-Free Indoor Localization Using Passive Infrared SensorsSensors10.3390/s2505136225:5(1362)Online publication date: 23-Feb-2025
    • (2025)Communication and Sensing: Wireless PHY-Layer Threats to Security and Privacy for IoT Systems and Possible CountermeasuresInformation10.3390/info1601003116:1(31)Online publication date: 7-Jan-2025
    • (2025)Real-Time Video Forgery Detection via Vision-WiFi Silhouette CorrespondenceIEEE Transactions on Mobile Computing10.1109/TMC.2024.348355024:3(1585-1601)Online publication date: Mar-2025
    • (2025)Non-Line-of-Sight Vehicle Localization Based on SoundIEEE Transactions on Intelligent Transportation Systems10.1109/TITS.2024.351058226:2(2321-2338)Online publication date: Feb-2025
    • (2025)Towards a low-cost and privacy-preserving indoor activity recognition system using wifi channel state informationMultimedia Tools and Applications10.1007/s11042-025-20650-3Online publication date: 28-Jan-2025
    • (2024)BFMSenseProceedings of the 21st USENIX Symposium on Networked Systems Design and Implementation10.5555/3691825.3691918(1697-1712)Online publication date: 16-Apr-2024
    • (2024)WiFi-Based Human Identification with Machine Learning: A Comprehensive SurveySensors10.3390/s2419641324:19(6413)Online publication date: 3-Oct-2024
    • (2024)Exposing Data Leakage in Wi-Fi CSI-Based Human Action Recognition: A Critical AnalysisInventions10.3390/inventions90400909:4(90)Online publication date: 15-Aug-2024
    • (2024)RM-CSTV: An effective high-resolution method of non-line-of-sight millimeter-wave radar 3-D imagingNational Science Open10.1360/nso/20230085(20230085)Online publication date: 20-Aug-2024
    • (2024)Wi-Fi Sensing Techniques for Human Activity Recognition: Brief Survey, Potential Challenges, and Research DirectionsACM Computing Surveys10.1145/3705893Online publication date: 25-Nov-2024
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