WiFi FTM, UWB and Cellular-Based Radio Fusion for Indoor Positioning

High-precision indoor localisation is becoming a necessity with novel location-based services that are emerging around 5G. The deployment of high-precision indoor location technologies is usually costly due to the high density of reference points. In this work, we propose the opportunistic fusion of several different technologies, such as ultra-wide band (UWB) and Wi-Fi fine-time measurement (FTM), in order to improve the performance of location. We also propose the use of fusion with cellular networks, such as LTE, to complement these technologies where the number of reference points is under-determined, increasing the availability of the location service. Maximum likelihood estimation (MLE) is presented to weight the different reference points to eliminate outliers, and several searching methods are presented and evaluated for the localisation algorithm. An experimental setup is used to validate the presented system, using UWB and Wi-Fi FTM due to their incorporation in the latest flagship smartphones. It is shown that the use of multi-technology fusion in trilateration algorithm remarkably optimises the precise coverage area. In addition, it reduces the positioning error by over-determining the positioning problem. This technique reduces the costs of any network deployment oriented to location services, since a reduced number of reference points from each technology is required.

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SiFi

ACM Transactions on Internet of Things ◽

10.1145/3450567 ◽

2021 ◽

Vol 2 (3) ◽

pp. 1-21

Author(s):

Deke Guo ◽

Xiaoqiang Teng ◽

Yulan Guo ◽

Xiaolei Zhou ◽

Zhong Liu

Keyword(s):

Rapid Development ◽

Estimation Method ◽

Likelihood Estimation ◽

Location Based Services ◽

Shopping Mall ◽

Inference Problem ◽

Indoor Location ◽

Label Semantics ◽

Geometrical Constraints ◽

Indoor Scenes

Due to the rapid development of indoor location-based services, automatically deriving an indoor semantic floorplan becomes a highly promising technique for ubiquitous applications. To make an indoor semantic floorplan fully practical, it is essential to handle the dynamics of semantic information. Despite several methods proposed for automatic construction and semantic labeling of indoor floorplans, this problem has not been well studied and remains open. In this article, we present a system called SiFi to provide accurate and automatic self-updating service. It updates semantics with instant videos acquired by mobile devices in indoor scenes. First, a crowdsourced-based task model is designed to attract users to contribute semantic-rich videos. Second, we use the maximum likelihood estimation method to solve the text inferring problem as the sequential relationship of texts provides additional geometrical constraints. Finally, we formulate the semantic update as an inference problem to accurately label semantics at correct locations on the indoor floorplans. Extensive experiments have been conducted across 9 weeks in a shopping mall with more than 250 stores. Experimental results show that SiFi achieves 84.5% accuracy of semantic update.

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INDOOR SPACE LOCATION MODEL BASED ON LOCATION SERVICE

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-4-w7-49-2017 ◽

2017 ◽

Vol XLII-4/W7 ◽

pp. 49-53

Author(s):

Y. Zhou ◽

G. Zeng ◽

Y. Huang ◽

X. Yang

Keyword(s):

Spatial Information ◽

Indoor Navigation ◽

Location Model ◽

Location Information ◽

Location Based Service ◽

Location Services ◽

Indoor Location ◽

Indoor Space ◽

Location Service ◽

Space Model

Location is the basis for the realization of location services, the integrity of the location information and its way of representation in indoor space model directly restricts the quality of location services. The construction of the existing indoor space model is mostly for specific applications and lack of uniform representation of location information. Several geospatial standards have been developed to meet the requirement of the indoor spatial information system, among which CityGML LOD4 and IndoorGML are the most relevant ones for indoor spatial information. However, from the perspective of Location Based Service (LBS), the CityGML LOD4 is more inclined to visualize the indoor space. Although IndoorGML is mainly used for indoor space navigation and has description (such as geometry, topology, and semantics) benefiting for indoor LBS, this standard model lack explicit representation of indoor location information. In this paper, from the perspective of Location Based Service (LBS), based on the IndoorGML standard, an indoor space location model (ISLM) conforming to human cognition is proposed through integration of the geometric and topological and semantic features of the indoor spatial entity. This model has the explicit description of location information which the standard indoor space model of IndoorGML and CityGML LOD4 does not have, which can lay the theoretical foundation for indoor location service such as indoor navigation, indoor routing and location query.

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Research on OpenLS-Based Mobile Location Service Platform

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.121-122.722 ◽

2010 ◽

Vol 121-122 ◽

pp. 722-727

Author(s):

Chi Jun Zhang ◽

Zheng Xuan Wang ◽

Yong Jian Yang

Keyword(s):

Large Scale ◽

Location Based Services ◽

Service Platform ◽

Location Services ◽

Domestic Industry ◽

Mobile Location ◽

Location Service ◽

Navigation Algorithm ◽

Location Algorithm ◽

Path Navigation

Currently, LBS (Location-based Services) as a new emerging business which is based on mobile communication network is becoming more and more popular. However domestic industry is lack of perfect location service platform and standards because of the complexity and large scale of LBS. Aimed at the cases, the architecture of mobile location service (MLS) platform based on OpenLS (OpenGIS® Location Services) standards is constructed in the paper, and makes it accord with the international standard. Moreover GIS (Geographic Information System) middleware model is also proposed in the paper. We encapsulate the secondary location algorithm and path navigation algorithm into GIS middleware and present four standard interfaces, which could support distributed management and improves the portability of the platform.

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Characterization of an Ultrasonic Local Positioning System for 3D Measurements

Sensors ◽

10.3390/s20102794 ◽

2020 ◽

Vol 20 (10) ◽

pp. 2794 ◽

Cited By ~ 2

Author(s):

Khaoula Mannay ◽

Jesús Ureña ◽

Álvaro Hernández ◽

Mohsen Machhout ◽

Taoufik Aguili

Keyword(s):

Low Cost ◽

Likelihood Estimation ◽

Indoor Positioning ◽

Global Navigation Satellite Systems ◽

Positioning System ◽

Fusion Algorithm ◽

Coverage Area ◽

Positioning Systems ◽

Indoor Location ◽

Local Positioning System

Indoor location and positioning systems (ILPS) are used to locate and track people, as well as mobile and/or connected targets, such as robots or smartphones, not only inside buildings with a lack of global navigation satellite systems (GNSS) signals but also in constrained outdoor situations with reduced coverage. Indoor positioning applications and their interest are growing in certain environments, such as commercial centers, airports, hospitals or factories. Several sensory technologies have already been applied to indoor positioning systems, where ultrasounds are a common solution due to its low cost and simplicity. This work proposes a 3D ultrasonic local positioning system (ULPS), based on a set of three asynchronous ultrasonic beacon units, capable of transmitting coded signals independently, and on a 3D mobile receiver prototype. The proposal is based on the aforementioned beacon unit, which consists of five ultrasonic transmitters oriented towards the same coverage area and has already been proven in 2D positioning by applying hyperbolic trilateration. Since there are three beacon units available, the final position is obtained by merging the partial results from each unit, implementing a minimum likelihood estimation (MLE) fusion algorithm. The approach has been characterized, and experimentally verified, trying to maximize the coverage zone, at least for typical sizes in most common public rooms and halls. The proposal has achieved a positioning accuracy below decimeters for 90% of the cases in the zone where the three ultrasonic beacon units are available, whereas these accuracies can degrade above decimeters according to whether the coverage from one or more beacon units is missing. The experimental workspace covers a large volume, where tests have been carried out at points placed in two different horizontal planes.

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Location-Based Services to Improve Elderly and Handicapped Citizens’ Mobility

Handbook of Research on ICTs and Management Systems for Improving Efficiency in Healthcare and Social Care ◽

10.4018/978-1-4666-3990-4.ch030 ◽

2013 ◽

pp. 577-594

Author(s):

César Benavente-Peces ◽

Ander Garcia-Gangoiti ◽

José Manuel Pardo-Martín ◽

Francisco Javier Ortega-González ◽

Javier Franco-Arroyo

Keyword(s):

Support Services ◽

New Technologies ◽

Location Based Services ◽

Portable Devices ◽

Location Services ◽

Gps Receivers ◽

Indoor Location ◽

Handicapped People ◽

Gps System

This chapter is aimed at the analysis and description of various wireless technologies and methods for indoor location of mobile/portable devices in order to provide support services to elderly and handicapped people as well as to care and medical services. Indoor location is an open problem that has been analyzed in the last years in order to provide location-based positioning services that can improve the quality of life of end users. GPS location is not possible in these environments due to the lack of satellite coverage. Satellites’ signals are absorbed by buildings’ elements and cannot reach GPS receivers. As a consequence, no location is obtained. One must take into account that many elderly and handicapped people are most of the time in an indoor location. Thus, new technologies and techniques have to be investigated in order to provide additional location services indoors that complement those provided in outdoor situations by the GPS system.

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INDOOR MAP AIDED INS/WI-FI INTEGRATED LBS ON SMARTPHONE PLATFORMS

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-annals-iv-2-w4-425-2017 ◽

2017 ◽

Vol IV-2/W4 ◽

pp. 425-429

Author(s):

C. Yu ◽

N. El-Sheimy

Keyword(s):

Kalman Filter ◽

Low Cost ◽

Integrated System ◽

Location Based Services ◽

Measurement Unit ◽

Indoor Location ◽

Location Service ◽

Positioning Errors ◽

Main Challenge ◽

Cascade Structure

In this research, an indoor map aided INS/Wi-Fi integrated location based services (LBS) applications is proposed and implemented on smartphone platforms. Indoor map information together with measurements from an inertial measurement unit (IMU) and Received Signal Strength Indicator (RSSI) value from Wi-Fi are collected to obtain an accurate, continuous, and low-cost position solution. The main challenge of this research is to make effective use of various measurements that complement each other without increasing the computational burden of the system. The integrated system in this paper includes three modules: INS, Wi-Fi (if signal available) and indoor maps. A cascade structure Particle/Kalman filter framework is applied to combine the different modules. Firstly, INS position and Wi-Fi fingerprint position integrated through Kalman filter for estimating positioning information. Then, indoor map information is applied to correct the error of INS/Wi-Fi estimated position through particle filter. Indoor tests show that the proposed method can effectively reduce the accumulation positioning errors of stand-alone INS systems, and provide stable, continuous and reliable indoor location service.

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WI-FI Access Point (WAP) OPTIMAL Placement in an Indoor Location

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2021.38128 ◽

2021 ◽

Vol 9 (9) ◽

pp. 1084-1087

Author(s):

Roohi Farheen

Keyword(s):

Simulated Annealing ◽

Data Communication ◽

Access Point ◽

Indoor Positioning ◽

Optimal Number ◽

Reference Points ◽

Optimal Placement ◽

Location Services ◽

Access Points ◽

Indoor Location

Abstract: The popularity of location based applications is undiminished today. They require accurate location information which is a challenging issue in indoor environments. Wireless technologies can help derive indoor positioning data. Especially, the WiFi technology is a promising candidate due to the existing and almost ubiquitous Wi-Fi infrastructure. The already deployed WiFi devices can also serve as reference points for localization eliminating the cost of setting up a dedicated system. However, the primary purpose of these Wi-Fi systems is data communication and not providing location services. This accuracy can be increased by carefully placing the Wi-Fi access points to cover the given territory properly. This method is based on simulated annealing which finds the optimal number and placement of Wi-Fi access points with regard to indoor positioning and investigate its performance in a real environment scenario via simulations. Keywords: Wi-fi access point (WAP), simulated annealing, router, wireless, placement, locationing.

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A New Type of 5G-Oriented Integrated BDS/SON High-Precision Positioning

Remote Sensing ◽

10.3390/rs13214261 ◽

2021 ◽

Vol 13 (21) ◽

pp. 4261

Author(s):

Wenhua Tong ◽

Decai Zou ◽

Tao Han ◽

Xiaozhen Zhang ◽

Pengli Shen ◽

...

Keyword(s):

High Precision ◽

Autonomous Driving ◽

Satellite System ◽

Significance Test ◽

Time Of Arrival ◽

Combined System ◽

Coverage Area ◽

Actual Measurement ◽

Location Services ◽

Stability And Accuracy

China is promoting the construction of an integrated positioning, navigation, and timing (PNT) systems with the BeiDou Navigation Satellite System (BDS) as its core. To expand the positioning coverage area and improve the positioning performance by taking advantage of device-to-device (D2D) and self-organizing network (SON) technology, a BDS/SON integrated positioning system is proposed for the fifth-generation (5G) networking environment. This system relies on a combination of time-of-arrival (TOA) and BeiDou pseudo-range measurements to effectively supplement BeiDou signal blind spots, expand the positioning coverage area, and realize higher precision in continuous navigation and positioning. By establishing the system state model, and addressing the single-system positioning divergence and insufficient accuracy, a robust adaptive fading filtering (RAF) algorithm based on the prediction residual is proposed to suppress gross errors and filtering divergence in order to improve the stability and accuracy of the positioning results. Subsequently, a federated Kalman filtering (FKF) algorithm operating in fusion-feedback mode is developed to centrally process the positioning information of the combined system. Considering that the prediction error can reflect the magnitude of the model error, an adaptive information distribution coefficient is introduced to further improve the filtering performance. Actual measurement and significance test results show that by integrating BDS and SON positioning data, the proposed algorithm realizes robust, reliable, and continuous high precision location services with anti-interference capabilities and good universality. It is applicable in scenarios involving unmanned aerial vehicles (UAVs), autonomous driving, military, public safety and other contexts and can even realize indoor positioning and other regional positioning tasks.

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