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Titre : GNSS/5G Hybridization for Urban Navigation Type de document : Thèse/HDR Auteurs : Anne-Marie Tobie, Auteur ; Axel Javier Garcia Pena, Directeur de thèse ; Paul Thevenon, Directeur de thèse Editeur : Toulouse : Université Fédérale Toulouse Midi-Pyrénées Année de publication : 2021 Importance : 287 p. Format : 21 x 30 cm Note générale : Bibliographie
Thèse pour obtenir le doctorat de l'Université de Toulouse, Spécialité Informatique et TélécommunicationsLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] 4G
[Termes IGN] 5G
[Termes IGN] bruit blanc
[Termes IGN] GNSS assisté pour la navigation
[Termes IGN] milieu urbain
[Termes IGN] modèle mathématique
[Termes IGN] positionnement en intérieur
[Termes IGN] positionnement par GNSS
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Termes IGN] simulation de signal
[Termes IGN] temps de propagation
[Termes IGN] trajet multipleIndex. décimale : THESE Thèses et HDR Résumé : (Auteur) Over the past few years, the need for positioning, and thus the number of positioning services in general, has been in constant growth. This need for positioning has been increasingly focused on constrained environments, such as urban or indoor environments, where GNSS (Global Navigation Satellite System) is known to have significant limitations: multipath as well as the lack of Line-of-Sight (LOS) satellite visibility degrades the GNSS positioning solution and makes it unsuitable for some urban or indoor applications. In order to improve the GNSS positioning performance in constrained environments, many solutions are already available: hybridization with additional sensors, [1], [2] or the use of signals of opportunity (SoO) for example, [3], [4], [5], [6], [7], [8]. Concerning SoO, mobile communication signals, such as the 4G Long Term Evolution (LTE) or 5G, are naturally envisioned for positioning, [3], [9], [10]. Indeed, a significant number of users are expected to be “connected-users” and 5G systems offers promising opportunities. 5G technology is being standardized at 3GPP [11]; the first complete release of 5G specifications, Release-15, was provided to the community in March 2018. 5G is an emerging technology and its positioning performance, as well as a potential generic receiver scheme to conduct positioning operations, is still under analysis. In order to study the potential capabilities provided by 5G systems and to develop a 5G-based generic positioning module scheme, the first fundamental step is to develop mathematical models of the processed 5G signals at each stage of the receiver for realistic propagation channel models: the mathematical expression of the useful received 5G signal as well as the AWG (Additive White Gaussian) noise statistics. In the Ph.D., the focus is given to the correlation operation which is the basic function implemented by typical ranging modules for 4G LTE signals [12], DVB signals [7], [8], and GNSS [13]. In fact, the knowledge of the correlation output mathematical model could allow for the development of optimal 5G signal processing techniques for ranging positioning. Previous efforts were made to provide mathematical models of received signals at the different receiver signal processing stages for signals with similar structures to 5G signals – Orthogonal Frequency Division Multiplexing (OFDM) signals as defined in 3GPP standard, [14]. OFDM signal-type correlator output mathematical model and acquisition techniques were derived in [7], [15]. Moreover, in [8], [15], tracking techniques were proposed, analyzed and tested based on the correlator output mathematical model of [7]. However, these models were derived by assuming a constant propagation channel over the duration of the correlation. Unfortunately, when the Channel Impulse Response (CIR) provided by a realistic propagation channel is not considered to be constant over the duration of the correlation, the correlator output mathematical models are slightly different from the mathematical models proposed in [7], [8]. Therefore, the first main point considered in the Ph.D. consists in the development of mathematical models and statistics of processed 5G signals for positioning. In order to derive accurate mathematical models, the time evolution impact of the 5G standard compliant propagation channel is of the utmost importance. Note that, in the Ph.D., the continuous CIR will be approximated by a discretized CIR, and the continuous time-evolution will be replaced by the propagation channel generation sampling rate notion. This approximation makes sense since, in a real transmission/reception chain, the received time-continuous signal is, at the output of the Radio-Frequency (RF) front-end, sampled. Therefore, a preliminary step, prior to derive accurate mathematical models of processed 5G signals, consists in determining the most suitable CIR-generation sampling interval for a selected 5G standard compliant propagation channel, QuaDRiGa: trade-off between having a realistic characterization and its complexity. Complexity is especially important for 5G compliant channels with multiple emitter and receiver antennas, and high number of multipath. Then, the impact of a time-evolving propagation channel inside an OFDM symbol duration is studied. A method to select the most appropriate CIR sampling interval for accurate modelling of symbol demodulation, correlator outputs and delay tracking will also be proposed. Based on the correlator output mathematical models developed for realistic multipath environments for both GNSS and 5G systems, ranging modules are then developed. These ranging modules outputs the pseudo ranging measurements required to develop navigation solution. In order to improve the positioning availability and GNSS positioning performance in urban environment through the exploitation of 5G signals, both systems, GNSS and 5G communication systems, must be optimally combined. In fact, in order to achieve this optimal combination, both types of signals must be optimally processed, and the mathematical model of their generated pseudo range measurements must be accurately characterized. The second main objective of the Ph.D. aims thus at realistically characterizing GNSS and 5G pseudo range measurement mathematical models and at developing hybrid navigation modules exploiting/adapted to the derived pseudo range measurements mathematical models. In order to validate, the mathematical models developed in the Ph.D., a simulator is designed. The pseudo range measurements mathematical models are derived from a realistic simulator which integrates a typical GNSS receiver processing module and a typical 5G signal processing module proposition; moreover, in order to achieve a realistic characterization, the simulator implements highly realistic propagation channels for GNSS, SCHUN [16], and for 5G, QuaDRiGa [17] is developed. The hybrid navigation modules to be implemented and compared in this work are an Extended Kalman Filter (EKF) and an Unscented Kalman Filter (UKF). The performances of these hybrid navigation modules are then studied to quantify the improvements bringing by 5G TOA measurements. Note de contenu : 1- Introduction
2- GNSS signals, measurement model and positioning
3- 5G systems
4- Mathematical models and statistics of processed 5G signals for ranging based positioning for a realistic propagation channel
5- Synchronization module of a 5G signal
6- Characterization of pseudo range measurement errors due to propagation channels
7- Positioning in urban environment using 5G and GNSS measurements
8- ConclusionNuméro de notice : 26526 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT/URBANISME Nature : Thèse française Note de thèse : Thèse de Doctorat : Informatique et Télécommunications : Toulouse : 2021 Organisme de stage : Laboratoire de recherche ENAC nature-HAL : Thèse Date de publication en ligne : 09/04/2021 En ligne : https://hal.science/tel-03189527/ Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97534 Intelligent sensors for positioning, tracking, monitoring, navigation and smart sensing in smart cities / Li Tiancheng (2021)
Titre : Intelligent sensors for positioning, tracking, monitoring, navigation and smart sensing in smart cities Type de document : Monographie Auteurs : Li Tiancheng, Éditeur scientifique ; Jan Junkun, Éditeur scientifique ; Cao Yue, Éditeur scientifique ; et al., Auteur Editeur : Bâle [Suisse] : Multidisciplinary Digital Publishing Institute MDPI Année de publication : 2021 Importance : 266 p. Format : 17 x 25 cm ISBN/ISSN/EAN : 978-3-0365-0123-9 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Intelligence artificielle
[Termes IGN] apprentissage automatique
[Termes IGN] capteur (télédétection)
[Termes IGN] cartographie et localisation simultanées
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] détection de cible
[Termes IGN] exploration de données
[Termes IGN] Extreme Gradient Machine
[Termes IGN] fusion de données
[Termes IGN] Inférence floue
[Termes IGN] internet des objets
[Termes IGN] logique floue
[Termes IGN] navigation autonome
[Termes IGN] odomètre
[Termes IGN] positionnement en intérieur
[Termes IGN] réseau de capteurs
[Termes IGN] simulation de signal
[Termes IGN] ville intelligenteRésumé : (éditeur) The rapid development of advanced, arguably, intelligent sensors and their massive deployment provide a foundation for new paradigms to combat the challenges that arise in significant tasks such as positioning, tracking, navigation, and smart sensing in various environments. Relevant advances in artificial intelligence (AI) and machine learning (ML) are also finding rapid adoption by industry and fan the fire. Consequently, research on intelligent sensing systems and technologies has attracted considerable attention during the past decade, leading to a variety of effective applications related to intelligent transportation, autonomous vehicles, wearable computing, wireless sensor networks (WSN), and the internet of things (IoT). In particular, the sensors community has a great interest in novel, intelligent information fusion, and data mining methods coupling AI and ML for substantial performance enhancement, especially for the challenging scenarios that make traditional approaches inappropriate. This reprint book has collected 14 excellent papers that represent state-of-the-art achievements in the relevant topics and provides cutting-edge coverage of recent advances in sensor signal and data mining techniques, algorithms, and approaches, particularly applied for positioning, tracking, navigation, and smart sensing. Note de contenu : 1- MIMU/odometer fusion with state constraints for vehicle positioning during BeiDou signal outage: Testing and results
2- Autonomous road roundabout detection and navigation system for smart vehicles and cities using laser simulator–fuzzy logic algorithms and sensor fusion
3- An elaborated signal model for simultaneous range and vector velocity estimation in FMCW radar
4- Hybrid solution combining Kalman filtering with Takagi–Sugeno fuzzy inference system for online car-following model calibration
5- Computationally efficient cooperative dynamic range-only SLAM based on sum of Gaussian filter
6- LoRaWAN geo-tracking using map matching and compass sensor fusion
7- A robust multi-sensor data fusion clustering algorithm based on density peaks
8- Extended target marginal distribution Poisson multi-Bernoulli mixture filter
9- A multi-core object detection coprocessor for multi-scale/type classification applicable to IoT devices
10- Leveraging uncertainties in softmax decision-making models for low-power IoT devices
11- Implementing deep learning techniques in 5G IoT networks for 3D indoor positioning: DELTA (DeEp Learning-Based Co-operaTive Architecture)
12- A novel hybrid algorithm based on Grey Wolf optimizer and fireworks algorithm
13- Passenger flow forecasting in metro transfer station based on the combination of singular spectrum analysis and AdaBoost-weighted extreme learning machine
14- A unified fourth-order tensor-based smart community systemNuméro de notice : 28609 Affiliation des auteurs : non IGN Thématique : IMAGERIE/INFORMATIQUE/POSITIONNEMENT Nature : Recueil / ouvrage collectif DOI : 10.3390/books978-3-0365-0123-9 En ligne : https://doi.org/10.3390/books978-3-0365-0123-9 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99453 Modeling multifrequency GPS multipath fading in land vehicle environments / Vicente Carvalho Lima Filho in GPS solutions, vol 25 n° 1 (January 2021)
[article]
Titre : Modeling multifrequency GPS multipath fading in land vehicle environments Type de document : Article/Communication Auteurs : Vicente Carvalho Lima Filho, Auteur ; Alison Moraes, Auteur Année de publication : 2021 Article en page(s) : 14 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] densité de probabilité
[Termes IGN] interférence
[Termes IGN] propagation du signal
[Termes IGN] qualité du signal
[Termes IGN] signal GPS
[Termes IGN] simulation de signal
[Termes IGN] trajet multiple
[Termes IGN] véhiculeRésumé : (auteur) The reliability and performance of GPS receivers depend on the quality of the signal received, which can be largely affected by the interference caused by buildings, trees, and other obstacles. Since obstacles are always present in practical applications, several statistical representations have been developed along the years to measure, predict, and compensate errors induced by interferences. Two of the most used models to characterize GPS signal fading are the Nakagami-m and Rice, but in this work, we present evidence that supports the κ–μ distribution as the best fit to deal with multifrequency GPS multipath channels inside urban, rural, and forest areas. A synthetic signal simulator was developed to create propagation cases involving scattering clusters and specular reflections. Additionally, experimental measurements are presented to confirm the κ–μ distribution as the best distribution to characterize different situations on the available three GPS frequencies. We then present typical values of fading coefficients in L1, L2C, and L5 signals, for cases involving urban canyons, regular urban, rural, and dense vegetation areas. These coefficients can also be used to evaluate the receiver performance under similar cases or may be applied in weights measurement methods for positioning computation improvement. Numéro de notice : A2021-002 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10291-020-01040-8 Date de publication en ligne : 09/10/2020 En ligne : https://doi.org/10.1007/s10291-020-01040-8 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96080
in GPS solutions > vol 25 n° 1 (January 2021) . - 14 p.[article]A first in-flight absolute calibration of the Chilean Earth Observation Satellite / C. Mattar in ISPRS Journal of photogrammetry and remote sensing, vol 92 (June 2014)
[article]
Titre : A first in-flight absolute calibration of the Chilean Earth Observation Satellite Type de document : Article/Communication Auteurs : C. Mattar, Auteur ; J. Hernandez, Auteur ; A. Santamaría-Artigas, Auteur ; M. Inzunza, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 16 - 25 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] capteur en peigne
[Termes IGN] capteur imageur
[Termes IGN] Chili
[Termes IGN] étalonnage de capteur (imagerie)
[Termes IGN] satellite d'observation de la Terre
[Termes IGN] simulation de signalRésumé : (Auteur) This work describes the first in-flight absolute calibration of the “Sistema Satelital para la Observación de la Tierra” (SSOT or Fasat-C). It was performed on January 29th 2013 at Antumapu site located in the southern area of Santiago, Chile. A description of the procedure is presented which includes both ground measurement and atmospheric characterization. The Chilean satellite for Earth observation carries on board a “New AstroSat Optical Modular Instrument” (NAOMI) high-resolution pushbroom imager which provides a 1.45 m ground sampling distance in the panchromatic (0.455–0.744 m) channel and a 5.8 m ground sampling distance for the green (0.455–0.52 m), blue (0.528–0.588 m), red (0.625–0.695 m) and near-infrared (0.758–0.881 m) channels from a 620 km orbit. Radiometric calibration was carried out in order to estimate the land leaving radiance and bidirectional reflectance at the top of the atmosphere. To correct the reflectance data for atmospheric effects, the Second Simulation of a Satellite Signal in the Solar Spectrum (6S) code was used. Aerosol Optical Depth (AOD), water vapor and ozone content were obtained from MOD04, MOD05 and MOD07 products respectively, which are derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) data. Statistical results such as BIAS, SIGMA and RMSE were calculated for the comparison between surface reflectance values and in situ measurements. Results show that the overall accuracy of the atmospherically corrected surface reflectance calculated from Fasat-C imagery can be estimated to around +5%, with a R2 coefficient of 0.939 between atmospherically corrected reflectance values and in situ measurements. The atmospheric correction applied in this work by combining MODIS data and the 6S radiative transfer code could be used for further calibration of the Fasat-C images, although in situ atmospheric irradiance measurements are necessary to estimate reliable values of surface reflectance. Future validation tasks have been considered for further applications to natural resources management and surface land cover classification. Numéro de notice : A2014-288 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.02.017 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.02.017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33191
in ISPRS Journal of photogrammetry and remote sensing > vol 92 (June 2014) . - pp 16 - 25[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 081-2014061 RAB Revue Centre de documentation En réserve L003 Disponible Generating distorded GNSS signals using a signal simulator / Mathieu Raimondi in GPS world, vol 24 n° 5 (May 2013)
[article]
Titre : Generating distorded GNSS signals using a signal simulator Type de document : Article/Communication Auteurs : Mathieu Raimondi, Auteur ; Eric Sénant, Auteur ; Charles Fernet, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 45 - 50 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] forme d'onde
[Termes IGN] positionnement par GNSS
[Termes IGN] signal Galileo
[Termes IGN] signal GPS
[Termes IGN] simulation de signalRésumé : (Auteur) INTEGRITY. It is one of the most desirable personality traits. It is the characteristic of truth and fair dealing, of honesty and sincerity. The word also can be applied to systems and actions with a meaning of soundness or being whole or undivided. This latter definition is clear when we consider that the word integrity comes from the Latin word integer, meaning untouched, intact, entire the same origin as that for the integers in mathematics: whole numbers without a fractional or decimal component. Integrity is perhaps the most important requirement of any navigation system (along with accuracy, availability, and continuity). It characterizes a system's ability to provide a timely warning when it fails to meet its stated accuracy. If it does not, we have an integrity failure and the possibility of conveying hazardously misleading information. GPS has built into it various checks and balances to ensure a fairly high level of integrity. However, GPS integrity failures have occasionally occurred. One of these was in 1990 when SVN19, a GPS Block II satellite operating as PRN19, suffered a hardware chain failure, which caused it to transmit an anomalous waveform, evidenced by carrier leakage on the L1 signal spectrum. Receivers continued to acquire and process the SVN19 signals, oblivious to the fact that the signal distortion resulted in position errors of three to eight meters. Errors of this magnitude would normally go unnoticed by most users, and the significance of the failure wasn't clear until March 1993 during some field tests of differential navigation for aided landings being conducted by the Federal Aviation Administration. The anomaly became known as the “evil waveform.”(I'm not sure who first came up with this moniker for the anomaly. Perhaps it was the folks at Stanford University who have worked closely with the FAA in its aircraft navigation research. The term has even made it into popular culture. The Japanese drone-metal rock band, Boris, released an album in 2005 titled Dronevil. One of the cuts on the album is “Evil Wave Form.” And if drone metal is not your cup of tea, you will find the title quite appropriate.). Other types of GPS evil waveforms are possible, and there is the potential for such waveforms to also occur in the signals of other global navigation satellite systems. It is important to fully understand the implications of these potential signal anomalies. In this month's column, our authors discuss a set of GPS and Galileo evil-waveform experiments they have carried out with an advanced GNSS RF signal simulator. Their results will help to benchmark the effects of distorted signals and perhaps lead to further improvements in GNSS signal integrity. Numéro de notice : A2013-250 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32388
in GPS world > vol 24 n° 5 (May 2013) . - pp 45 - 50[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 067-2013051 RAB Revue Centre de documentation En réserve L003 Disponible Simulating GPS signals / A. Brown in GPS world, vol 23 n° 5 (May 2012)PermalinkUtilities and communications / F. Weimann in GPS world, vol 18 n° 11 (November 2007)PermalinkEvaluating an indoor GPS receiver / A. Teubner in GEO: Geoconnexion international, vol 4 n° 8 (september 2005)PermalinkPermalink