A Survey of Positioning Systems Using Visible LED Lights

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.As Global Positioning System (GPS) cannot provide satisfying performance in indoor environments, indoor positioning technology, which utilizes indoor wireless signals instead of GPS signals, has grown rapidly in recent years. Meanwhile, visible light communication (VLC) using light devices such as light emitting diodes (LEDs) has been deemed to be a promising candidate in the heterogeneous wireless networks that may collaborate with radio frequencies (RF) wireless networks. In particular, light-fidelity has a great potential for deployment in future indoor environments because of its high throughput and security advantages. This paper provides a comprehensive study of a novel positioning technology based on visible white LED lights, which has attracted much attention from both academia and industry. The essential characteristics and principles of this system are deeply discussed, and relevant positioning algorithms and designs are classified and elaborated. This paper undertakes a thorough investigation into current LED-based indoor positioning systems and compares their performance through many aspects, such as test environment, accuracy, and cost. It presents indoor hybrid positioning systems among VLC and other systems (e.g., inertial sensors and RF systems). We also review and classify outdoor VLC positioning applications for the first time. Finally, this paper surveys major advances as well as open issues, challenges, and future research directions in VLC positioning systems.Peer reviewe

Optical Camera Communications: Principles, Modulations, Potential and Challenges

Optical wireless communications (OWC) are emerging as cost-effective and practical solutions to the congested radio frequency-based wireless technologies. As part of OWC, optical camera communications (OCC) have become very attractive, considering recent developments in cameras and the use of fitted cameras in smart devices. OCC together with visible light communications (VLC) is considered within the framework of the IEEE 802.15.7m standardization. OCCs based on both organic and inorganic light sources as well as cameras are being considered for low-rate transmissions and localization in indoor as well as outdoor short-range applications and within the framework of the IEEE 802.15.7m standardization together with VLC. This paper introduces the underlying principles of OCC and gives a comprehensive overview of this emerging technology with recent standardization activities in OCC. It also outlines the key technical issues such as mobility, coverage, interference, performance enhancement, etc. Future research directions and open issues are also presented

Software-Defined Lighting.

For much of the past century, indoor lighting has been based on incandescent or gas-discharge technology. But, with LED lighting experiencing a 20x/decade increase in flux density, 10x/decade decrease in cost, and linear improvements in luminous efficiency, solid-state lighting is finally cost-competitive with the status quo. As a result, LED lighting is projected to reach over 70% market penetration by 2030. This dissertation claims that solid-state lighting’s real potential has been barely explored, that now is the time to explore it, and that new lighting platforms and applications can drive lighting far beyond its roots as an illumination technology. Scaling laws make solid-state lighting competitive with conventional lighting, but two key features make solid-state lighting an enabler for many new applications: the high switching speeds possible using LEDs and the color palettes realizable with Red-Green-Blue-White (RGBW) multi-chip assemblies. For this dissertation, we have explored the post-illumination potential of LED lighting in applications as diverse as visible light communications, indoor positioning, smart dust time synchronization, and embedded device configuration, with an eventual eye toward supporting all of them using a shared lighting infrastructure under a unified system architecture that provides software-control over lighting. To explore the space of software-defined lighting (SDL), we design a compact, flexible, and networked SDL platform to allow researchers to rapidly test new ideas. Using this platform, we demonstrate the viability of several applications, including multi-luminaire synchronized communication to a photodiode receiver, communication to mobile phone cameras, and indoor positioning using unmodified mobile phones. We show that all these applications and many other potential applications can be simultaneously supported by a single lighting infrastructure under software control.PhDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/111482/1/samkuo_1.pd

Comunicações com câmara e aprendizagem automática para posicionamento por luz visível em espaços interiores

In this dissertation, a 3D indoor visible light positioning system based on machine learning and optical camera communications is presented. The system uses LED (light-emitting diode) luminaires as reference points and a rolling shutter complementary metal-oxide semiconductor (CMOS) sensor as the receiver. The LED luminaires are modulated using On-Off Keying (OOK) with unique frequencies. You Only Look Once version 5 (YOLOv5) is used for classification and estimation of the position of each visible LED luminaire in the image. The pose of the receiver is estimated using a perspective-npoint (PnP) problem algorithm. The system is validated using a real-world sized setup containing eight LED luminaires, and achieved an average positioning error of 3.5 cm. The average time to compute the camera pose is approximately 52 ms, which makes it suitable for real-time positioning. To the best of our knowledge, this is the first application of the YOLOv5 algorithm in the field of VLP for indoor environments.Nesta dissertação, é apresentado um sistema de posicionamento 3D por luz visível, baseado em aprendizagem automática e comunicações com câmara. O sistema foi desenvolvido para espaços interiores e utiliza luminárias LED (díodo emissor de luz) como pontos de referência e um sensor CMOS (complementary metal-oxide semiconductor) como recetor. As luminárias LED são moduladas utilizando OOK (On–Off Keying) com frequências únicas. O algoritmo YOLOv5 (You Only Look Once version 5) é utilizado para classificar e estimar a posição de cada luminária LED visível na imagem. A posição e orientação do recetor é estimada utilizando um algoritmo de geometria projetiva. O sistema foi validado utilizando um setup em tamanho real com 8 luminárias LED, e obteve um erro de posicionamento médio de 3.5 cm. O tempo médio para obter a posição e orientação da câmara é de aproximadamente 52ms, o que torna o sistema adequado para posicionamento em tempo real. Tanto quanto sabemos, esta é a primeira aplicação do algoritmo YOLOv5 para localização por luz visível em espaços interiores.Mestrado em Engenharia Eletrónica e Telecomunicaçõe

An Implementation Approach and Performance Analysis of Image Sensor Based Multilateral Indoor Localization and Navigation System

Optical camera communication (OCC) exhibits considerable importance nowadays in various indoor camera based services such as smart home and robot-based automation. An android smart phone camera that is mounted on a mobile robot (MR) offers a uniform communication distance when the camera remains at the same level that can reduce the communication error rate. Indoor mobile robot navigation (MRN) is considered to be a promising OCC application in which the white light emitting diodes (LEDs) and an MR camera are used as transmitters and receiver respectively. Positioning is a key issue in MRN systems in terms of accuracy, data rate, and distance. We propose an indoor navigation and positioning combined algorithm and further evaluate its performance. An android application is developed to support data acquisition from multiple simultaneous transmitter links. Experimentally, we received data from four links which are required to ensure a higher positioning accuracy

Visible Light Optical Camera Communication for Electroencephalography Applications

Due to the cable-free deployment and flexibility of wireless communications, the data transmission in the applications of home and healthcare has shown a trend of moving wired communications to wireless communications. One typical example is electroencephalography (EEG). Evolution in the radio frequency (RF) technology has made it is possible to transmit the EEG data without data cable bundles. However, presently, the RF-based wireless technology used in EEG suffers from electromagnetic interference and might also have adverse effects on the health of patient and other medical equipment used in hospitals or homes. This puts some limits in RF-based EEG solutions, which is particularly true in RF restricted zones like Intensive Care Units (ICUs). As a recently developed optical wireless communication (OWC) technology, visible light communication (VLC) using light-emitting diodes (LEDs) for both simultaneous illumination and data communication has shown its advantages of free from electromagnetic interference, potential huge unlicensed bandwidth and enhanced data privacy due to the line transmission of light. The most recent development of VLC is the optical camera communication (OCC), which is an extension of VLC IEEE standard 802.15.7, also referred to as visible light optical camera communication (VL-OCC). Different from the conventional VLC where traditional photodiodes are used to detect and receive the data, VL-OCC uses the imaging camera as the photodetector to receive the data in the form of visible light signals. The data rate requirement of EEG is dependent on the application; hence this thesis investigates a low cost, organic LED (OLED)-driven VL-OCC wireless data transmission system for EEG applications

Etäisyyden huomioiva kaksiulotteinen viivakoodi mobiilikäyttötapauksiin

Global internet use is becoming increasingly mobile, and mobile data usage is growing exponentially. This puts increasing stress on the radio frequency spectrum that cellular and Wi-Fi networks use. As a consequence, research has also been conducted to develop wireless technologies for other parts of the electromagnetic spectrum – namely, visible light. One approach of using the visible light channel for wireless communication leverages barcodes. In this thesis, we propose a 2D barcode that can display different information based on the distance between the barcode and the scanner. Earlier research on distance-sensitive barcodes has focused on providing a closer viewer more information as a closer viewer can see more detail. In contrast, we target use cases where a clear physical separation between users of different roles can be made, such as presentation systems. We evaluate two methods of achieving distance-awareness: color-shifting of individual colors, where a color changes tone at longer distances, and color blending, where two colors blend into a third color at longer viewing distances. Our results show that a modern smartphone is capable of leveraging color-shifting in ideal conditions, but external changes such as ambient lighting render color-shifting unusable in practical scenarios. On the other hand, color blending is robust in varying indoor conditions and can be used to construct a reliable distance-aware barcode. Accordingly, we employ color blending to design a distance-aware barcode. We implement our solution in an off-the-shelf Android smartphone. Experimental results show that our scheme achieves a clear separation between close and far viewers. As a representative use case, we also implement a presentation system where a single barcode provides the presenter access to presentation tools and the audience access to auxiliary presentation material.Maailmanlaajuinen internetin käyttö muuttuu yhä liikkuvammaksi, ja mobiilidatan käyttö kasvaa eksponentiaalisesti. Tämä kohdistaa yhä suurempia vaatimuksia radiotaajuusspektriin, jota mobiili- ja Wi-Fi-verkot käyttävät. Näin ollen tutkijat ovat kehittäneet langattomia teknologioita hyödyntäen myös muita sähkömagneettisen spektrin osia – erityisesti näkyvää valoa. Yksi näkyvän valon sovellus langattomassa viestinnässä ovat viivakoodit. Tässä työssä kehitämme kaksiulotteisen viivakoodin, joka pystyy välittämään eri tietoa katselijoille eri etäisyyksillä. Aiempi etäisyyden huomioivien viivakoodien tutkimus on keskittynyt tarjoamaan lähellä olevalle katselijalle enemmän tietoa, koska läheinen katselija näkee viivakoodin tarkemmin. Sitä vastoin me keskitymme käyttötapauksiin, joissa eri käyttäjäroolien välillä on selkeä etäisyydellinen ero, kuten esimerkiksi esitelmissä puhujan ja yleisön välillä. Tarkastelemme kahta menetelmää: yksittäisten värien muutoksia etäisyyden muuttuessa ja kahden värin sekoittumista etäisyyden kasvaessa. Tulostemme perusteella nykyaikainen älypuhelin pystyy hyödyntämään yksittäisten värien muutoksia ihanteellisissa olosuhteissa, mutta ulkoiset tekijät, kuten ympäristön valaistus, aiheuttavat liian suuria värimuutoksia käytännön käyttötapauksissa. Toisaalta värien sekoittuminen on johdonmukaista muuttuvassa sisäympäristössä ja sitä voidaan käyttää luotettavan viivakoodin luomisessa. Näin ollen me suunnittelemme etäisyyden huomioivan viivakoodin hyödyntäen värien sekoittumista. Toteutamme ratkaisumme yleisesti saatavilla olevalle Android-älypuhelimelle. Kokeellisten tulostemme perusteella menetelmämme saavuttaa selkeän erottelun läheisten ja kaukaisten katselijoiden välillä. Esimerkkikäyttötapauksena toteutamme myös esitelmäjärjestelmän, jossa sama viivakoodi antaa lähellä olevalle puhujalle nopean pääsyn esitystyökaluihin ja kauempana olevalle yleisölle pääsyn esityksen apumateriaaliin

LED Location Beacon System Based on Processing of Digital Images

This paper is in the field of vehicle positioning technology for the Intelligent Transportation Systems. The ideas of an innovative light-emitting diode (LED)-based location beacon system are developed and verified. The system developed is a combination of several latest technologies which include a CMOS vision sensor, high brightness LEDs, and digital image processing techniques. It belongs to a new kind of simplex communication link. A digital camera is used to capture images contained in the LED beacon signal. The captured digital images are processed by the algorithms developed and a location code is extracted. The location code can be used for calibration of a vehicle positioning system which may consist of a GPS, Inertial Navigation System (INS) and other sensors. The issues examined include the structure of the transmitter and the receiver, the signaling method, the transmission protocol of the LED panel, the relationship between the camera capturing rate and the LED pattern update rate, the digital camera exposure technology, and the efficiency of the image processing algorithms. Experiments using a prototype transmitter and a receiver were performed. The experimental results provide a good demonstration of the viability of the ideas and methodologies developed.published_or_final_versio