Please Stand By: TV-based indoor localization

in 28th IEEE Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC-2017) (2017, October)

Despite the decades of efforts, indoor positioning remains an open research challenge. While existing solutions already demonstrate high accuracy, their in-building infrastructure --- such as Wi-Fi access ... [more ▼]

Despite the decades of efforts, indoor positioning remains an open research challenge. While existing solutions already demonstrate high accuracy, their in-building infrastructure --- such as Wi-Fi access points or Bluetooth beacons --- provides only a limited coverage. This paper investigates feasibility of accurate indoor positioning using broadcast digital TV signals, readily available in populated areas worldwide. We experiment with the classic received signal strength (RSS) fingerprinting, and introduce a novel approach based on channel state information (CSI), which leverages frequency-selective multipath fading of wideband TV signals. The proposed methods are experimentally evaluated on an extensive dataset of DVB-T signals, systematically collected in two large buildings over the course of 8 months. The results show that the proposed approach consistently outperforms RSS fingerprinting and achieves 92--98% localization accuracy. While this study is based on the European DVB-T signals, the proposed method is directly generalizable to other TV standards (such as ATSC, ISDB, DTMB and DMB) and wide-area TV white space (TVWS) networks. [less ▲]

Indoor localization using ambient FM radio RSS fingerprinting: A 9-month study

in 17th IEEE International Conference on Computer and Information Technology (CIT-2017) (2017, August)

While indoor positioning systems aspire for higher accuracy, their coverage is typically limited to buildings with dedicated hardware. A possible alternative is offered by infrastructure-free positioning ... [more ▼]

While indoor positioning systems aspire for higher accuracy, their coverage is typically limited to buildings with dedicated hardware. A possible alternative is offered by infrastructure-free positioning methods. In particular, several studies have demonstrated feasibility of indoor positioning using broadcast FM radio signals, which are available in most populated areas worldwide. However, previous work provides little information about long-term performance of FM-based indoor localization. This paper presents a longitudinal study of FM indoor positioning based on received signal strength (RSS) fingerprinting. We evaluate system's performance on a large dataset of real-world FM signals, systematically collected in several large-scale multi-floor testbeds over the course of 9 months. We also investigate the impact of different classifiers, training schedules and fingerprint sizes on localization accuracy. The results demonstrate that well-trained FM-based system can provide reliable indoor positioning even several months after deployment. [less ▲]

Indoor positioning and floor plan based ground truth: Can you really click where you are?

in 15th International Conference on Mobile and Ubiquitious Multimedia (MUM-2016) (2016, December)

The increasing accuracy of indoor positioning systems requires an appropriately accurate evaluation, which compares system outputs with the known coordinates of test locations --- the ground truth ... [more ▼]

The increasing accuracy of indoor positioning systems requires an appropriately accurate evaluation, which compares system outputs with the known coordinates of test locations --- the ground truth. Although ground truth data are rarely (if ever) tested, they are traditionally assumed to be perfectly accurate. However, even small errors introduced by inaccurate ground truth need to be taken into account for fair evaluation and comparison between modern high-resolution positioning systems. In this paper we analyze the quality of ground truth data provided by clicking on an interactive floor plan (a method employed by such classical systems as RADAR and Horus). Experimental results show that this method has high precision but low accuracy, and high systematic errors make it unsuitable for evaluation of fine-grained localization systems. [less ▲]

HIPS: Human-based indoor positioning system

in Proceedings of the 7th International Conference on Indoor Positioning and Indoor Navigation (IPIN-2016) (2016, October)

Activity tracking and indoor positioning with a wearable magnet

Poster (2015, September)

This paper presents an unconventional application of digital compass sensors for localization and activity monitoring in ambient assisted living scenarios. Benefits and limitations of the proposed ... [more ▼]

This paper presents an unconventional application of digital compass sensors for localization and activity monitoring in ambient assisted living scenarios. Benefits and limitations of the proposed approach are reviewed and compared to these of traditional tracking methods, such as wearable devices, surveillance cameras and device-free localization. [less ▲]

Colorizer: Smart Glasses Aid for the Colorblind

in WearSys'15 (2015, May)

We present a smart glasses application for helping colorblind people to distinguish problematic colors in daily life. The prototype processes a live video stream from the mobile camera, remaps colors ... [more ▼]

We present a smart glasses application for helping colorblind people to distinguish problematic colors in daily life. The prototype processes a live video stream from the mobile camera, remaps colors according to the user needs, and displays the augmented result. Color transformation ensures high contrast between colors which are otherwise indistinguishable for the user. [less ▲]

Device-Free Indoor Localization Based on Ambient FM Radio Signals

in International Journal of Ambient Computing and Intelligence (2014), 6(January-March), 35-44

This paper presents the concept of device-free indoor localization using only a passive receiver and ambient FM radio signals. Experimental results based on empirical measurements demonstrate the ... [more ▼]

This paper presents the concept of device-free indoor localization using only a passive receiver and ambient FM radio signals. Experimental results based on empirical measurements demonstrate the feasibility of the proposed approach. We also evaluate fine-grained localization performance of the system, its temporal stability, and highlight the role of frequency diversity for passive localization. [less ▲]

(Semi-) Pervasive Gaming Educational and Entertainment Facilities via Interactive Video-to-Video Communication over the Internet, for Museum Exhibits

in Papadopoulos, Harris; Andreou, Andreass; Iliadis, Lazaros (Eds.) et al Artificial Intelligence Applications and Innovations (2013)

Based upon the core concept of the LiveCity Project we focus on the specific City Cultural Experiences v2v Pilot,designed to allow for visitors at two defined locations to interact with one another in a ... [more ▼]

Based upon the core concept of the LiveCity Project we focus on the specific City Cultural Experiences v2v Pilot,designed to allow for visitors at two defined locations to interact with one another in a joint experience and to get educational/entertainment benefits, originating directly from the museum content delivery. We discuss a set of semi-pervasive games (the so-called “Twin Cities”games) which are designed to bring people together at remotely twinned locations through the use of video-to-video communication and multitouch interaction. We also present an early classification of video-to-video (v2v) interaction games that is designed to inform designers about the potential of such technologies. We classify them as: using video for awareness and communication, interacting with video and video as a game. [less ▲]