UltraSE: Single-Channel Speech Enhancement Using Ultrasound
Ke Sun, Xinyu Zhang
ACM MobiCom 2021, Oct 2021.

We propose UltraSE, which uses ultrasound sensing as a complementary modality to separate the desired speaker’s voice from interferences and noise.

ExGSense: Toward Facial Gesture Sensing and Reconstruction with a Sparse Near-Eye Sensor Array
Chen Chen, Ke Sun, Xinyu Zhang
ACM/IEEE IPSN 2021, May 2021.

ExGSense propose to sense whole facial gestures by using a sparse set of biopotential transducers. We propose a dual-branch multiview representation learning model, which can explicitly exploit the sensor diversities across time-frequency-spatial domains.

"Alexa, Stop Spying on Me": Speech Privacy Protection Against Voice Assistants
Ke Sun, Chen Chen, Xinyu Zhang
ACM SenSys 2020, Nov 2020.

MicShield is a companion device with voice assistant to enable the selective jamming mechanism which, for the first time, prevents VAs from recording private speech without affecting the voice assistants’ normal functionalities.

milliEgo: Single-chip mmWave Radar Aided Egomotion Estimation via Deep Sensor Fusion
Chris Xiaoxuan Lu, Muhamad Risqi U. Saputra, Peijun Zhao, Yasin Almalioglu, Pedro P. B. de Gusmao, Changhao Chen, Ke Sun, Niki Trigoni, Andrew Markham
ACM SenSys 2020, Nov 2020.

milliEgo is a novel deep-learning approach that demonstrates the feasibility of mmWave odometry and provides a fusion framework to develop a robust mmWaveInertial Odometry.

Dynamic Speed Warping: Similarity-Based One-shot Learning for Device-free Gesture Signals
Xun Wang, Ke Sun, Ting Zhao, Wei Wang, Qing Gu
IEEE INFOCOM 2020, April 2020.

We propose a Dynamic Speed Warping (DSW) algorithm to enable one-shot learning for device-free gesture signals performed by different users. DSW provides a robust similarity measure between gesture samples and can work for both one-shot learning in supervised gesture recognition and unsupervised learning tasks.

SpiderMon: Towards Using Cell Towers as Illuminating Sources for Keystroke Monitoring
Kang Ling, Yuntang Liu, Ke Sun, Wei Wang, Lei Xie, Qing Gu
IEEE INFOCOM 2020, April 2020.

SpiderMon is a system that performs longrange keystroke monitoring using the signal transmitted by commercial 4G/5G cellular base stations. We show that SpiderMon can detect keystroke movements at a distance of 15 meters or even behind the wall.

VSkin: Sensing Touch Gestures on Surfaces of Mobile Devices Using Acoustic Signals
Ke Sun, Ting Zhao, Wei Wang, Lei Xie
ACM MobiCom 2018, October 2018.

VSkin is a system that supports fine-grained touch gesture sensing on the back of mobile devices based on acoustic signals. VSkin utilizes both the structure-borne sounds, i.e., sounds propagating through the structure of the device, and the air-borne sounds, i.e., sounds propagating through the air, to sense touch gestures.

Unlock With Your Heart: Heartbeat-based Authentication on Commercial Mobile Phones
Lei Wang, Kang Huang, Ke Sun, Wei Wang, Chen Tian, Lei Xie, Qing Gu
ACM IMWUT (UbiComp) 2018, October 2018.

''Unlock with your heart'' uses the built-in accelerometer to capture the heartbeat signals on commercial mobile phones. The user only needs to press the phone on his/her chest, and the system can identify the user within a few heartbeats.

Depth Aware Finger Tapping on Virtual Displays
Ke Sun, Wei Wang, Alex X. Liu, Haipeng Dai
ACM MobiSys 2018, June 2018.

Dolphin is a fine-grained depthaware tapping scheme that can provide high accuracy tapping detection. It uses light-weight ultrasound based sensing, along with one COTS mono-camera, to enable 3D tracking of fingers.

Device-free Gesture Tracking using Acoustic Signals
Wei Wang, Alex X. Liu, Ke Sun
ACM MobiCom 2016, October 2016.

LLAP is an ultrasound-based device-free gesture tracking scheme that can be deployed on existing mobile devices as software, without any hardware modification. We use speakers and microphones that already exist on most mobile devices to perform device-free tracking of a hand/finger.
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