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Intelligent Metasurface Imager and Recognizer [article]

Lianlin Li, Ya Shuang, Qian Ma, Haoyang Li, Hanting Zhao, Menglin Wei1, Che Liu, Chenglong Hao, Cheng-Wei Qiu, Tie Jun Cui
2019 arXiv   pre-print
whole image; and recognizing human hand signs instantly at Wi-Fi frequency of 2.4 GHz.  ...  We also show that the proposed intelligent metasurface system work well even when it is passively excited by stray Wi-Fi signals that ubiquitously exist in our daily lives.  ...  (a) In-situ imaging results using the intelligent metasurface excited with commodity Wi-Fi signals.  ... 
arXiv:1910.00497v1 fatcat:qzo2oqnlcbe5tdoyybdmwvtusm

Intelligent metasurface imager and recognizer

Lianlin Li, Ya Shuang, Qian Ma, Haoyang Li, Hanting Zhao, Menglin Wei, Che Liu, Chenglong Hao, Cheng-Wei Qiu, Tie Jun Cui
2019 Light: Science & Applications  
whole image, and recognizing human hand signs instantly at a Wi-Fi frequency of 2.4 GHz.  ...  To accomplish complicated successive tasks using a single device in real time, we propose the simultaneous use of a smart metasurface imager and recognizer, empowered by a network of artificial neural  ...  Wi-Fi signals. a In situ imaging results using the intelligent metasurface excited with commodity Wi-Fi signals.  ... 
doi:10.1038/s41377-019-0209-z pmid:31645938 pmcid:PMC6804847 fatcat:ooynctsttbgyjhgahyvsk6kooy

Full Respiration Rate Monitoring Exploiting Doppler Information with Commodity Wi-Fi Devices

Chendan Dou, Hao Huan
2021 Sensors  
Commercial Wi-Fi devices can provide a non-invasive, cost-effective and long-term respiration rate-monitoring scheme for home scenarios.  ...  Based on these ideas, we design a complete respiration rate-monitoring system to obtain the respiration rate by using the consistency between the Doppler energy change period and the respiratory cycle.  ...  We design a complete set of respiration rate-monitoring system by using commodity Wi-Fi device on the basis of the analytical result.  ... 
doi:10.3390/s21103505 pmid:34069847 pmcid:PMC8157398 fatcat:fh4ubxkqgnhofmj553vgzbhodm

RF-Based Human Activity Recognition Using Signal Adapted Convolutional Neural Network

Zhe Chen, Chao Cai, Tianyue Zheng, Jun Luo, Jie Xiong, Xin Wang
2021 IEEE Transactions on Mobile Computing  
Human Activity Recognition (HAR) plays a critical role in a wide range of real-world applications, and it is traditionally achieved via wearable sensing.  ...  Recently, to avoid the burden and discomfort caused by wearable devices, device-free approaches exploiting RF signals arise as a promising alternative for HAR.  ...  The detection output of data used in Fig. 10 is shown in Fig. 11 which indicates a human motion is detected.  ... 
doi:10.1109/tmc.2021.3073969 fatcat:i76w5e4nebei3cp63mqtzd5ipq


Youwei Zeng, Dan Wu, Jie Xiong, Enze Yi, Ruiyang Gao, Daqing Zhang
2019 Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies  
We believe this is the first system to enable through-wall respiration sensing with commodity WiFi devices and the proposed method could also benefit other sensing applications.  ...  The past few years have witnessed the great potential of exploiting channel state information retrieved from commodity WiFi devices for respiration monitoring.  ...  For convenience, we use the term "HRD" (Human Respiration Detection) to represent the respiration detection system proposed in [47] .Proc. ACM Interact. Mob.  ... 
doi:10.1145/3351279 fatcat:5ash37cmr5anxbtc2guv7x4wka

Channel State Information from Pure Communication to Sense and Track Human Motion: A Survey

Mohammed A. A. Al-qaness, Mohamed Abd Elaziz, Sunghwan Kim, Ahmed A. Ewees, Aaqif Afzaal Abbasi, Yousif A. Alhaj, Ammar Hawbani
2019 Sensors  
These fluctuations can be used to track object (i.e., a human) motion in indoor environments.  ...  The main Wi-Fi sensing methods can be broadly categorized as Received Signal Strength Indicator (RSSI), Wi-Fi radar (by using Software Defined Radio (SDR)) and Channel State Information (CSI).  ...  devices Some Wi-Fi devices Table 3 . 3 Some of the classifiers that are used to classify CSI-based human motion detection.  ... 
doi:10.3390/s19153329 fatcat:u2aukowrxzbrja4rcwtbz6svi4

Exploring LoRa for Long-range Through-wall Sensing

Fusang Zhang, Zhaoxin Chang, Kai Niu, Jie Xiong, Beihong Jin, Qin Lv, Daqing Zhang
2020 Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies  
Experimental results show that (1) human respiration can still be sensed when the target is 25 meters away from the LoRa devices, and 15 meters away with a wall in between; and (2) human walking (both  ...  We further build a prototype system which is capable of sensing both coarse-grained and fine-grained human activities.  ...  For example, Zhang et al. leverage commodity Wi-Fi devices to detect human respiration, which could be 2-4 meters away from each other [63] [62] .  ... 
doi:10.1145/3397326 fatcat:xsvxcxr4rvfrbdqiq25d33agaq

Develop an Adaptive Real-Time Indoor Intrusion Detection System Based on Empirical Analysis of OFDM Subcarriers

Wei Zhuang, Yixian Shen, Lu Li, Chunming Gao, Dong Dai
2021 Sensors  
We prototype our system on commercial Wi-Fi devices and compare the overall performance with those of state-of-the-art approaches.  ...  Device-free passive intrusion detection is a promising technology to determine whether moving subjects are present without deploying any specific sensors or devices in the area of interest.  ...  We implemented our system with commodity Wi-Fi devices and evaluated its performance for various scenarios, including low speed and high speed for intruder motion, LOS and NLOS, single intruder and multiple  ... 
doi:10.3390/s21072287 pmid:33805870 fatcat:ilo5or56zrcotpgertxywil7ya

Wi-COVID: A COVID-19 Symptom Detection and Patient Monitoring Framework using WiFi

Fangyu Li, Maria Valero, Hossain Shahriar, Rumi Ahmed Khan, Sheikh Iqbal Ahamed
2020 Smart Health  
In this paper, we explore the possibility of monitoring respiration rates (RR) of COVID-19 patients using a widely-available technology at home - WiFi.  ...  Using the at-home WiFi signals, we propose Wi-COVID, a non-invasive and non-wearable technology to monitor the patient and track RR for the healthcare provider.  ...  Then, we introduce the proposed Wi-COVID framework in Section 3. The design of the WiFi-based system is represented in Section 4. We demonstrate preliminary results in Section 5.2.  ... 
doi:10.1016/j.smhl.2020.100147 pmid:33251320 pmcid:PMC7680085 fatcat:asgyrbkve5endpxm52z5ye5l4m

Implementation of unobtrusive sensing systems for elderly care: Scoping review (Preprint)

Nikita Sharma, Jeroen Klein Brinke, J.E.W.C. Van Gemert - Pijnen, L.M.A. Braakman - Jansen
2021 JMIR Aging  
Using these criteria, we screened studies by title, abstract, and full text.  ...  Finally, this review has extended the discussion about unobtrusiveness as a property of systems that cannot be measured in binary because it varies greatly with user perception and context.  ...  system using electrostatic sensing. [57] Li, X. et al.(2018) WiVit: Design a vitality monitoring system (detect motion and location) using Wi-Fi devices. [58] Lin, W. et al.(2018) DW-Health: Recognize  ... 
doi:10.2196/27862 pmid:34612822 pmcid:PMC8529483 fatcat:7mmp2lwlfreebeaqc472w4goo4

A Lightweight Passive Human Tracking Method Using Wi-Fi

Jian Fang, Lei Wang, Zhenquan Qin, Bingxian Lu, Wenbo Zhao, Yixuan Hou, Jenhui Chen
2022 Sensors  
For this reason, in this paper, we propose a Wi-Fi-enabled Infrared-like Device-free (WIDE) method for target tracking to realize a lightweight target-tracking method.  ...  Secondly, we make full use of the network structure formed by a large number of wireless devices already deployed in reality to achieve the goal.  ...  The device-free indoor human tracking system (IndoTrack) [2] proposes Doppler-MUSIC and Doppler-AoA methods to extract and estimate velocity and location information from CSI with only commodity Wi-Fi  ... 
doi:10.3390/s22020541 pmid:35062501 pmcid:PMC8781929 fatcat:maqe4un74rbdhkogly2hxtgrxa

WiFind: Driver fatigue detection with fine-grained Wi-Fi signal features

Weijia Jia, Hongjian Peng, Na Ruan, Zhiqing Tang, Wei Zhao
2018 IEEE Transactions on Big Data  
WiFind can be easily deployed in a commodity Wi-Fi infrastructure, and we have evaluated its performance in real driving environments.  ...  In our work, we propose a novel Wi-Fi signals based fatigue detection approach, called WiFind to overcome the drawbacks as associated with the current works.  ...  The other researchers explore the propagation rule of Wi-Fi to understand and evaluate the human respiration detection in [15] [17] .  ... 
doi:10.1109/tbdata.2018.2848969 fatcat:lpa3r3x2efeozc6oafrbcknfsm

WiBreathe: Estimating respiration rate using wireless signals in natural settings in the home

Ruth Ravichandran, Elliot Saba, Ke-Yu Chen, Mayank Goel, Sidhant Gupta, Shwetak N. Patel
2015 2015 IEEE International Conference on Pervasive Computing and Communications (PerCom)  
Our work extends past approaches of using wireless signals for respiratory monitoring by using only a single transmitter-receiver pair at the same frequency range of commodity Wi-Fi signals to estimate  ...  Furthermore, we demonstrate the capability of WiBreathe in detecting multiple people and by extension, their respiration rates.  ...  This would make the system truly ubiquitous and allow a Wi-Fi router to receive RF signals from any single Wi-Fi transmitting device (Access point, cellphone, laptop, smart TV, etc.) for respiratory rate  ... 
doi:10.1109/percom.2015.7146519 dblp:conf/percom/RavichandranSCG15 fatcat:3psaclqgorhrfe7r5oc4b7cpze

Unlocking the Beamforming Potential of LoRa for Long-range Multi-target Respiration Sensing

Fusang Zhang, Zhaoxin Chang, Jie Xiong, Rong Zheng, Junqi Ma, Kai Niu, Beihong Jin, Daqing Zhang
2021 Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies  
Extensive experiments show that our system can monitor the respiration rates of five human targets simultaneously at an average accuracy of 98.1%.  ...  Despite extensive research effort in contact-free sensing using RF signals in the last few years, there still exist significant barriers preventing their wide adoptions.  ...  To sense multiple targets simultaneously, we propose a receiver-side LoRa beamforming approach.  ... 
doi:10.1145/3463526 fatcat:pfolzc4pqjdtjlieqapqye5cs4

Pushing the Physical Limits of IoT Devices with Programmable Metasurfaces [article]

Lili Chen, Wenjun Hu, Kyle Jamieson, Xiaojiang Chen, Dingyi Fang, Jeremy Gummeson
2020 arXiv   pre-print
We integrate our metasurface into an IoT network as LAMA, a Low-power Lattice of Actuated Metasurface Antennas, designed for the pervasively used 2.4 GHz ISM band.  ...  Small, low-cost IoT devices are typically equipped with only a single, low-quality antenna, significantly limiting communication range and link quality.  ...  To validate this, we consider human respiration detection as a case study to test LLAMA's potential.  ... 
arXiv:2007.11503v2 fatcat:yn7pm6suivde3egr7bfsx6lz4e
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