Indoor localization is of great importance for a range pervasive applications, attracting many research efforts in the past two decades. Most radio-based solutions require process site survey, which radio signatures are collected and stored further comparison matching. Site survey involves intensive costs on manpower time. In this work, we study unexploited RF signal characteristics leverage user motions to construct floor plan that previously obtained by survey. On basis, design WILL, an...

Crowd counting, which count or accurately estimate the number of human beings within a region, is critical in many applications, such as guided tour, crowd control and marketing research analysis. A counting solution should be scalable minimally intrusive (i.e., device-free) to users. Image-based solutions are device-free, but cannot work well dim dark environment. Non-image based usually require every being carrying device, inaccurate unreliable practice. In this paper, we present FCC,...

Regular free-weight exercise helps to strengthen the body's natural movements and stabilize muscles that are important strength, balance, posture of human beings. Prior works have exploited wearable sensors or RF signal changes (e.g., WiFi Blue tooth) for activity sensing, recognition countingetc.. However, none them incorporate three key factors necessary a practical monitoring system: recognizing activities on site, assessing their qualities, providing useful feedbacks bodybuilder...

Device-free object tracking provides a promising solution for many localization and systems to monitor non-cooperative objects, such as intruders, which do not carry any transceiver. However, existing device-free solutions mainly use special sensors or active RFID tags, are much more expensive compared passive tags. In this paper, we propose novel motion detection method using named Twins. The leverages newly observed phenomenon called critical state caused by interference among We...

Indoor localization is of great importance for a range pervasive applications, attracting many research efforts in the past two decades. Most radio-based solutions require process site survey, which radio signatures are collected and stored further comparison matching. Site survey involves intensive costs on manpower time. In this work, we study unexploited RF signal characteristics leverage user motions to construct floor plan that previously obtained by survey. On basis, design WILL, an...

Localization is a fundamental issue of wireless sensor networks that has been extensively studied in the literature. Our real-world experience from GreenOrbs, network system deployed forest, shows localization wild remains very challenging due to various interfering factors. In this paper, we propose CDL, Combined and Differentiated approach for exploits strength range-free approaches range-based using received signal indicator (RSSI). A critical observation ranging quality greatly impacts...

Physical-layer identification utilizes unique features of wireless devices as their fingerprints, providing authenticity and security guarantee. Prior physical-layer techniques on radio frequency (RFID) tags require nongeneric equipments are not fully compatible with existing standards. In this paper, we propose a novel system, GenePrint, for UHF passive tags. The GenePrint prototype system is implemented by commercial reader, USRP-based monitor, off-the-shelf Our solution generic completely...

Device-to-device communication is important to emerging mobile applications such as Internet of Things and social networks. Authentication key agreement among multiple legitimate devices the first step build a secure channel. Existing solutions put into physical proximity use common radio environment proof identities secret agree on same key. However they experience very slow bit generation rate high errors, requiring several minutes 256-bit In this work, we design implement an...

The research on Wi-Fi sensing has been thriving over the past decade but process not smooth. Three barriers always hamper research: 1) unknown baseband design and its influence; 2) inadequate hardware; 3) lack of versatile flexible measurement software. This article tries to eliminate these through following work. <i>First</i>, we present an in-depth study Qualcomm Atheros AR9300 (QCA9300) NIC. We identify a missing item existing channel state information (CSI) model, namely, CSI distortion,...

Comparing to well protected data frames, Wi-Fi management frames (MFs) are extremely vulnerable various attacks. Since MFs transmitted without encryption or authentication, attackers can easily launch attacks by forging the MFs. In a collaborative environment with many sniffers, such be detected sensing anomaly RSS changes. However, it is quite difficult identify these spoofing assistance from other nodes. By exploiting some unique characteristics (e.g., rapid spatial decorrelation,...

Different from online shopping, in-store shopping has few ways to collect the customer behaviors before purchase. In this paper, we present design and implementation of an on-site Customer Behavior IDentification system based on passive RFID tags, named CBID. By collecting analyzing wireless signal features, CBID can detect track tag movements further infer corresponding behaviors. We model three main objectives behavior identification by concrete problems solve them using novel protocols...

Device to device (D2D) communication is expected become a promising technology of the next-generation wireless systems. Security issues have technical barriers D2D due its "open-air" nature and lack centralized control. Generating symmetric keys individually on different parties without key exchange or distribution desirable but challenging. Recent work has proposed extract from measurement physical layer random variations channel, e.g., channel state information (CSI) orthogonal...

Crowd density estimating is a crucial service in many applications (e.g., smart guide, crowd control, etc.), which often conducted using pattern recognition technologies based on video surveillance. However, these kinds of methods are high cost, and cannot work well low-light environments. Radio frequency adopted more indoor application, since radio signal strength (RSS) can be easily obtained by various wireless devices without additional cost. In this paper, we introduce low cost method...

Device-free based object tracking provides a promising solution for many localization and systems to monitor non-cooperative objects which do not carry any transceiver such as intruders. However, existing device-free solutions mainly use sensors active RFID tags, are much more expensive compared passive tags. In this paper, we propose novel motion detection method using named Twins. The leverages phenomenon called critical state caused by interference among We theoretically explain via an...

This paper presents RF-Mehndi, a passive commercial RFID tag array formed identifier. The key RF-Mehndi novelty is that when the user's fingertip touching on surface during communication, backscattered signals by become user-dependent and unique. Hence, if we enhance communication modality of many personal cards nowadays in case card gets lost or stolen, it cannot be used illegally adversaries. To harvest such benefit, have two observations designing RF-Mehndi. first observation tags are...

Regular free-weight exercise helps to strengthen natural movements and stabilize muscles that are important strength, balance, posture of human beings. Prior works have exploited wearable sensors or RF signal changes for activity sensing, recognition, counting, etc.. However, none them incorporated three key factors necessary a practical monitoring system: recognizing activities on site, assessing their qualities, providing useful feedbacks the bodybuilder promptly. Our FEMO system provides...

Federated learning (FL) is an emerging distributed and privacy-preserving machine framework. However, the performance of traditional FL methods seriously impaired by real-world data, which appear to be non-IID. The recent clustered federated (CFL) eliminate impact non-IID data grouping clients with similar distribution into same cluster. Unfortunately, existing CFL heavily rely on pre-setting cluster number, failing achieve adaptive client clustering. We also experimentally observe that...

An important function of smart environments is the ubiquitous access computing devices. In public areas such as hospitals, libraries, and airports, people may want to interact with nearby systems get information, directions a hospital room, locations books, flight departure/arrival information. Touch screen based displays kiosks, which are commonly used today, incur extra hardware cost or even possible germ bacteria infection. This work provides new solution: users can make queries inputs by...

Multi-node localization is crucial for large-scale and densely deployed Internet of Things (IoT) devices connected via LoRaWAN. Due to limitations in bandwidth the number RX chains (antennas), existing LoRaWAN-based methods often rely on frequency hopping or additional infrastructure improve location accuracy. Although promising, these struggle localize multiple nodes during packet collisions. In this paper, we propose MC-LoRa, which features a multi-node pipeline that includes reliable...