Grid-based RFID Indoor Localization Using Tag Read Count and Received Signal Strength Measurements PDF Download

Author: Nanda Gopal Jeevarathnam
Publisher:
ISBN:
Category : Radio frequency identification systems
Languages : en
Pages : 60

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Book Description
Passive ultra-high frequency (UHF) radio frequency identification (RFID) systems have gained immense popularity in recent years for their wide-scale industrial applications in inventory tracking and management. In this study, we explore the potential of passive RFID systems for indoor localization by developing a grid-based experimental framework using two standard and easily measurable performance metrics: received signal strength indicator (RSSI) and tag read count (TRC). We create scenarios imitating real life challenges such as placing metal objects and other RFID tags in two different read fields (symmetric and asymmetric) to analyze their impacts on location accuracy. We study the prediction potential of RSSI and TRC both independently and collaboratively. In the end, we demonstrate that both signal metrics can be used for localization with sufficient accuracy whereas the best performance is obtained when both metrics are used together for prediction on an artificial neural network especially for more challenging scenarios. Experimental results show an average error of as low as 0.286 (where consecutive grid distance is defined as unity) which satisfies the grid-based localization benchmark of less than 0.5.

Author: Ramprabhu Jayaraman
Publisher:
ISBN:
Category : Radio frequency identification systems
Languages : en
Pages : 70

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Book Description
Passive radio frequency identification (RFID) systems are revolutionizing the indoor positioning and tracking applications. There has been substantial research on practical applications of this technology and hospitals especially trauma care units are one such area where this capability can lead to improved workflow. Our system uses the Alien RFID reader and the "Squiggle" passive RFID tags to create an effective solution for tracking various medical items. Based on the Received Signal Strength Indication (RSSI) value of the tags, we developed a localization algorithm which uses a neural network estimator to estimate the distances of the tags. To reduce the effect of noise in the RSSI values received from the reader, we accumulate data over a period of time, remove the outliers and the average the remaining RSSI values. The RSSI based estimation algorithm provides very accurate estimation when the spatial density of tags is low (about 25 tags per square meter). To improve the localization accuracy at higher spatial densities we augmented the RSSI method of estimating distances by using the number of times the tags were read or the "read-count'. We also investigated how different types of occluding materials affect the localization accuracy. Metal and Humans also can cause complete occlusion when the positioned in direct line of sight between the antenna and the tag. To overcome human based occlusion, we placed an additional ceiling mounted antenna per 10 m2. This intervention makes possible the detection (but not localization) of tags when the vertical field of view is not occluded. We also studied the effect of the material to which the tags are attached and determined the effects on localization accuracy. The software system developed using Java is designed in a modular fashion and provides interfaces to tools like Matlab so that it is easy to experiment to various other localization algorithms. We also developed an intuitive User Interface to display the locations of tags and the associated items. Once a tag is identified its associated description can be looked up in a computer database and this also can be displayed in the user interface.

Author: Jiaqing Wu (Engineer)
Publisher:
ISBN: 9781267797865
Category : Radio frequency identification systems
Languages : en
Pages : 183

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Book Description
Radio Frequency Identification (RFID) is an information exchange technology based on radio waves communication. It is also a possible solution to indoor localization. Due to multipath propagation and anisotropic interference in the indoor environment, theoretical propagation models are generally not sufficient for RFID-based localization. In fact, the radio frequency (RF) signal distribution may not even be monotonic and this makes range-based localization algorithms less accurate. On the other hand, range free localization algorithms, such as k Nearest-Neighbor (kNN), require reference tags to be spread throughout the whole three-dimensional (3D) space which is simply not practical. In this work, a hybrid real-time localization algorithm that combines reference tags with Received Signal Strength Indicator (RSSI) ranging is introduced to improve RFID-based 3D localization in high-complexity indoor environments. The experiments demonstrate that the proposed system is more accurate than traditional algorithms under real world constraints. The active RFID system includes 4 readers and 24 reference tags deployed in a fully furnished room. The localization algorithm is implemented in MATLAB and is synchronized with RF signal data collection in real-time. The results show that the novel hybrid algorithm achieves an average 3D localization error of 1.08m which represents a significant improvement over kNN and RSSI algorithms under the same circumstance. A battery-assisted passive RFID system was deployed side-by-side to the active system for comparison. Furthermore, the reader and tag performance was evaluated in both high-complexity laboratory environment and International Space Station (ISS) mock-up with high-reflection interior surface. In addition, theoretical models on minimum number of required reference tags and localization error prediction were introduced.

Author: Mohammed Rana Basheer
Publisher:
ISBN:
Category : Radio
Languages : en
Pages : 428

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Book Description
"Locating and tracking assets in an indoor environment is a fundamental requirement for several applications which include for instance network enabled manufacturing. However, translating time of flight-based GPS technique for indoor solutions has proven very costly and inaccurate primarily due to the need for high resolution clocks and the non-availability of reliable line of sight condition between the transmitter and receiver. In this dissertation, localization and tracking of wireless devices using radio signal strength (RSS) measurements in an indoor environment is undertaken. This dissertation is presented in the form of five papers. The first two papers deal with localization and placement of receivers using a range-based method where the Friis transmission equation is used to relate the variation of the power with radial distance separation between the transmitter and receiver. The third paper introduces the cross correlation based localization methodology. Additionally, this paper also presents localization of passive RFID tags operating at 13.56MHz frequency or less by measuring the cross-correlation in multipath noise from the backscattered signals. The fourth paper extends the cross-correlation based localization algorithm to wireless devices operating at 2.4GHz by exploiting shadow fading cross-correlation. The final paper explores the placement of receivers in the target environment to ensure certain level of localization accuracy under cross-correlation based method. The effectiveness of our localization methodology is demonstrated experimentally by using IEEE 802.15.4 radios operating in fading noise rich environment such as an indoor mall and in a laboratory facility of Missouri University of Science and Technology. Analytical performance guarantees are also included for these methods in the dissertation"--Abstract, leaf iv.

Author: Bhavik Contractor
Publisher:
ISBN:
Category : Radio frequency identification systems
Languages : en
Pages : 75

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Book Description
The advent of GPS has redefined the need of a positioning system in today*’s ubiquitous computing world. While GPS works satisfactorily and is quite a norm in an outdoor environment, it fails to work indoors due to the inherent complexity of an indoor environment. There is an ever increasing need to develop an indoor positioning system and a lot of research has been done to solve the problem of indoor localization. These solutions differ on the basis of cost, dependency on environment, line of sight requirements and so on. Passive RFID (Radio Frequency Identification) tags pose an interesting solution to the problem of indoor localization, given the ease of deployment and the cost effective infrastructure. It is less expensive to tag items with RFID tags, than to attach them with sensor nodes. In this thesis, the problem of using the RFID technology for two dimensional indoor localization is studied. A relatively inexpensive technique requiring just one RFID reader and multiple passive RFID tags is adopted. The idea is to use multilateration among the passive tags to solve the problem of localization. A ranging technique is developed to establish a relationship between signal strength and distance. The concept of Received Signal Strength calibration is used to develop the ranging technique, and to account for the effects of dynamic environmental conditions on localization. Finally, an error map matching technique is employed to counter the errors in localization.

Author: Alseny Diallo
Publisher:
ISBN:
Category : Global Positioning System
Languages : en
Pages :

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Book Description
Location-based services (LBSs) are significantly becoming a vital part of life. Global Navigation Satellite Systems such as GPS have been used in a wide range of applications, from transport navigation, and synchronization of telecommunications networks. GPS works remarkably well in outdoor positioning. However, GPS does not perform well when the target object is close to walls, buildings, trees, or indoor environments. This is because the signal from the GPS satellites is too weak to penetrate an obstacle like concrete walls and buildings. Due to the complicated characteristics of indoor environments, the development of an indoor localization technique is always linked with a set of difficulties. For instance, indoor localization systems are challenged by the influence of obstacles like equipment, movement of human beings, doors, walls, and more. To overcome those challenges, we propose an indoor localization system that uses radio frequency identification tags or RFID tags to localize moving targets. Our indoor localization algorithm derives the accurate location of a target object using a set of RFID tags deployed in a predefined area. Our localization algorithm derives the target device’s location based on the signal it receives from surrounding tags. Depending on the number of tags in the surrounding area, the algorithm uses different formulas to calculate the target’s location. Specifically, there are three different cases. A case where a target object is nearby one tag, two tags or three tags. The localization algorithm works well when an area is well covered by tags. To optimize the coverage using a limited number of tags, we developed a greedy algorithm that uses a novel score function to help deploy the RFID tags in a predefined area to guarantee maximum coverage. This approach is evaluated using both simulation and real system use cases. Additionally, we designed a system deployment that uses the localization algorithm and the tag deployment algorithm to track several target objects in a 2-dimensional space. The system is proven to be reliable, fault-tolerant and scale very well with an increase in workload. The results show our approach is effective in localizing target objects with high accuracy.

Author: Chenshu Wu
Publisher: Springer
ISBN: 9811303568
Category : Computers
Languages : en
Pages : 225

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Book Description
This book provides a comprehensive and in-depth understanding of wireless indoor localization for ubiquitous applications. The past decade has witnessed a flourishing of WiFi-based indoor localization, which has become one of the most popular localization solutions and has attracted considerable attention from both the academic and industrial communities. Specifically focusing on WiFi fingerprint based localization via crowdsourcing, the book follows a top-down approach and explores the three most important aspects of wireless indoor localization: deployment, maintenance, and service accuracy. After extensively reviewing the state-of-the-art literature, it highlights the latest advances in crowdsourcing-enabled WiFi localization. It elaborated the ideas, methods and systems for implementing the crowdsourcing approach for fingerprint-based localization. By tackling the problems such as: deployment costs of fingerprint database construction, maintenance overhead of fingerprint database updating, floor plan generation, and location errors, the book offers a valuable reference guide for technicians and practitioners in the field of location-based services. As the first of its kind, introducing readers to WiFi-based localization from a crowdsourcing perspective, it will greatly benefit and appeal to scientists and researchers in mobile and ubiquitous computing and related areas.

Author: Bin Zhou
Publisher:
ISBN:
Category :
Languages : en
Pages :

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Author: Rainer Mautz
Publisher: Sudwestdeutscher Verlag Fur Hochschulschriften AG
ISBN: 9783838135373
Category :
Languages : en
Pages : 152

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Book Description
In the age of automation the ability to navigate persons and devices in indoor environments has become increasingly important for a rising number of applications. However, we are still far away from achieving cheap provision of global indoor positioning with an accuracy of 1 meter or better. With the emergence of global satellite positioning systems, the performance of outdoor positioning has become excellent, but many mass market applications require seamless positioning capabilities in all environments. Therefore indoor positioning has become a focus of research and development during the past decade. This book categorizes all sighted indoor positioning approaches into 13 distinct technologies and describes the measuring principles of each. Individual approaches are characterized and key performance parameters are quantified.

Author: Mao, Guoqiang
Publisher: IGI Global
ISBN: 1605663972
Category : Computers
Languages : en
Pages : 526

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Book Description
Wireless localization techniques are an area that has attracted interest from both industry and academia, with self-localization capability providing a highly desirable characteristic of wireless sensor networks. Localization Algorithms and Strategies for Wireless Sensor Networks encompasses the significant and fast growing area of wireless localization techniques. This book provides comprehensive and up-to-date coverage of topics and fundamental theories underpinning measurement techniques and localization algorithms. A useful compilation for academicians, researchers, and practitioners, this Premier Reference Source contains relevant references and the latest studies emerging out of the wireless sensor network field.