In this paper, we propose Airshark—a system that detects multiple non-WiFi RF devices in real-time and using only commodity WiFi hardware. To motivate the need for systems like Airshark, we start with measurement study that characterizes the usage and prevalence of non-WiFi devices across many locations. We then present the design and implementation of Airshark. Airshark extracts unique feature...

WiFi localization based on fingerprinting method became popular during last decade. However, collecting information to construct a WiFi signal map is challenging due to high cost. We assume that it is possible to gather such information with cheap cost using crowd sourcing with smartphones. Each user’s current location is estimated by either GPS, WiFi, radio cell signals or manually set by the ...

To exploit the complementary strengths of WiFi positioning, pedestrian dead reckoning (PDR), and landmarks, we propose a novel fusion approach based on an extended Kalman filter (EKF). For WiFi positioning, unlike previous fusion approaches setting measurement noise parameters empirically, we deploy a kernel density estimation-based model to adaptively measure the related measurement noise stat...

The IEEE 802.11 standard is coming from 1999. Since that time lots of research paper were born analyzing WiFi networks. However, until the recent years, WiFi devices and drivers were on closed source, so measurements could rely only on those features that the vendors offered for them. For such reason there could be hardly any research focusing on the bit level internals of WiFi transmissions. T...

WiFi-based localization is a popular approach for positioning a WiFi-enabled device in an indoor environment. Most implementations rely on querying fingerprint databases, created by stop and go sampling of WiFi signals at discrete locations used as reference points. In this paper, we propose an approach for rapid creation of a dense WiFi fingerprint database using a human operated ambulatory ba...

WiFi technology has been embraced by a large number of consumers at home and in the vertical markets such as enterprises, education, and healthcare. WiFi is experiencing extremely rapid growth on all fronts, including the number of public hotspots, the number of devices with built-in support for WiFi, and the number of upstart WiFi carriers. Cellular service providers have recently jumped on th...

Enhanced Positioning Systems (EPS) are able to supplement Global Positioning Systems (GPS) in indoor environments where GPS cannot work because of disrupted or weak signals. Most EPS are Wifi-based because Wifi is a common technology available in many indoor environments and is deployed in cost effective manner. Fingerprinting and Trilateration are the two general methods used for calculating p...

Spectrum scarcity is known to be main obstacle to scaling of wireless network capacity. Spectrum sharing is a solution to this problem. The unlicensed ISM band is getting crowded by WLAN and WPAN users and devices. Spectrum sharing within the devices of same network is not a problem. But coexistence of WLAN and WPAN (eg: WiFi and ZigBee) is a challenging problem. Spectrum sharing among these ne...

Electrocardiogram and arterial pressure measurements were studied under acute exposures to WIFI (2.45GHz) during one hour in adult male rabbits. Antennas of WIFI were placed at 25cm at the right side near the heart. Acute exposure of rabbits to WIFI increased heart frequency (+22%) and arterial blood pressure (+14%). Moreover, analysis of ECG revealed that WIFI induced a combined increase of PR...

Future mobile networks will exploit unlicensed spectrum to boost capacity and meet growing user demands costeffectively. The 3GPP has recently defined a Licensed-Assisted Access (LAA) scheme to enable global Unlicensed LTE (U-LTE) deployment, aiming at (i) ensuring fair coexistence with incumbent WiFi networks, i.e., impacting on their performance no more than another WiFi device, and (ii) achi...