Journal ArticleDOI
Tool release: gathering 802.11n traces with channel state information
Daniel Halperin,Wenjun Hu,Anmol Sheth,David Wetherall +3 more
- Vol. 41, Iss: 1, pp 53-53
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TLDR
The measurement setup comprises the customized versions of Intel's close-source firmware and open-source iwlwifi wireless driver, userspace tools to enable these measurements, access point functionality for controlling both ends of the link, and Matlab scripts for data analysis.Abstract:
We are pleased to announce the release of a tool that records detailed measurements of the wireless channel along with received 802.11 packet traces. It runs on a commodity 802.11n NIC, and records Channel State Information (CSI) based on the 802.11 standard. Unlike Receive Signal Strength Indicator (RSSI) values, which merely capture the total power received at the listener, the CSI contains information about the channel between sender and receiver at the level of individual data subcarriers, for each pair of transmit and receive antennas.Our toolkit uses the Intel WiFi Link 5300 wireless NIC with 3 antennas. It works on up-to-date Linux operating systems: in our testbed we use Ubuntu 10.04 LTS with the 2.6.36 kernel. The measurement setup comprises our customized versions of Intel's close-source firmware and open-source iwlwifi wireless driver, userspace tools to enable these measurements, access point functionality for controlling both ends of the link, and Matlab (or Octave) scripts for data analysis. We are releasing the binary of the modified firmware, and the source code to all the other components.read more
Citations
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Journal ArticleDOI
Wi-Fi-Based Fall Detection Using Spectrogram Image of Channel State Information
TL;DR: In this paper , the authors proposed a spectrogram-image-based fall detection using Wi-Fi channel state information (CSI), which is segmented with a certain sliding-time window, and then the classifier detects fall by using the spectrogram image generated from the segmented CSI.
Proceedings ArticleDOI
InaudibleKey: Generic Inaudible Acoustic Signal based Key Agreement Protocol for Mobile Devices
Weitao Xu,Zhenjiang Li,Wanli Xue,Xiaotong Yu,Bo Wei,Jia Wang,Chengwen Luo,Wei Li,Albert Y. Zomaya +8 more
TL;DR: InaudibleKey as discussed by the authors exploits the acoustic channel frequency response of two legitimate devices as a common secret to generate keys, which improves key generation rate by 3 times, extends pairing distance by 3.2 times, and reduces information reconciliation counts by 2.5 times.
Journal ArticleDOI
Wi-CaL: WiFi Sensing and Machine Learning Based Device-Free Crowd Counting and Localization
TL;DR: Wang et al. as mentioned in this paper proposed a simultaneous crowd counting and localization system by using ESP32 modules for WiFi links and extracted several features that contribute to dynamic state (moving crowd) and static state (location of the crowd) from the CSI bundles.
Proceedings ArticleDOI
Non-Line-of-Sight Around the Corner Human Presence Detection Using Commodity WiFi Devices
TL;DR: This work proposes to augment the sensing capability of a robot by using a commodity WiFi receiver that can observe the changes in the properties of received signals, and thus be able to infer whether a human is present behind the wall or obstacles, which enhances its ability to plan and navigate efficiently and intelligently.
Posted Content
We Can "See" You via Wi-Fi - WiFi Action Recognition via Vision-based Methods
TL;DR: A novel de-noising method based on Singular Value Decomposition (SVD) to eliminate the background energy and effectively extract the channel information of signals reflected by human bodies and to minimize the effect of location dependency embedded in CSI.
References
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Proceedings ArticleDOI
Predictable 802.11 packet delivery from wireless channel measurements
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