Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317359
Petra Píšová, O. Kalden, N. Douchin, B. Carreras, A. Vemuru
Within this research, two ray-tracing models for simulation of Global Navigation Satellite System (GNSS) signals reception at airports were developed. For each satellite, the algorithms determine whether the signal has arrived at the receiver through a direct path or after multiple reflections. Furthermore, the algorithms are able to estimate the number of multipath reflections and the coordinates of the reflection points within the 3D environment model. The models are established and validated using simulated as well as real data. They are especially designed for complex environments and situations where positioning with highest accuracy is required, which is the case for the Ground Based Augmentation Systems (GBAS).
{"title":"Multipath Location Methodology for Ground Based Augmentation Systems","authors":"Petra Píšová, O. Kalden, N. Douchin, B. Carreras, A. Vemuru","doi":"10.23919/ENC48637.2020.9317359","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317359","url":null,"abstract":"Within this research, two ray-tracing models for simulation of Global Navigation Satellite System (GNSS) signals reception at airports were developed. For each satellite, the algorithms determine whether the signal has arrived at the receiver through a direct path or after multiple reflections. Furthermore, the algorithms are able to estimate the number of multipath reflections and the coordinates of the reflection points within the 3D environment model. The models are established and validated using simulated as well as real data. They are especially designed for complex environments and situations where positioning with highest accuracy is required, which is the case for the Ground Based Augmentation Systems (GBAS).","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125960466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317382
I. Klein, I. Rusnak, Y. Bar-Shalom
The fine alignment process is aimed to reduce initial attitude and inertial sensors errors before system operation. Such process is critical for the navigation solution accuracy, in particular, for situations of pure inertial navigation. In this paper, we compare different types of adaptive extended Kalman filters for a scenario of velocity aided fine alignment. Results show that a proper choice of an adaptive filter in the alignment process can greatly improve the accuracy of the navigation error-states. As a result, the time duration of the fine alignment process can be shortened.
{"title":"Comparison Between Adaptive Extended Kalman Filters for INS Accurate Fine Alignment Process","authors":"I. Klein, I. Rusnak, Y. Bar-Shalom","doi":"10.23919/ENC48637.2020.9317382","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317382","url":null,"abstract":"The fine alignment process is aimed to reduce initial attitude and inertial sensors errors before system operation. Such process is critical for the navigation solution accuracy, in particular, for situations of pure inertial navigation. In this paper, we compare different types of adaptive extended Kalman filters for a scenario of velocity aided fine alignment. Results show that a proper choice of an adaptive filter in the alignment process can greatly improve the accuracy of the navigation error-states. As a result, the time duration of the fine alignment process can be shortened.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"1016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127427218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317366
David Obregón, Raúl Arnau, María Campo-Cossio, Alejandro Nicolás, M. Pattinson, Smita Tiwari, Ander Ansuategi, C. Tubío, Joaquin Reyes
Greenpatrol project aims to develop a robotic prototype for pest detection and treatment in greenhouse crops. The robot platform uses a sensor fusion approach with Global Navigation Satellite System (GNSS), odometers, inertial and range sensors in order to obtain a position and heading solution with the required precision to navigate inside the greenhouse and to localize accurately the pests. Previously some tests were carried out inside a greenhouse to verify its localization subsystem performance, but due to the difficulties to get a reliable ground truth, additional tests in open sky conditions has been done. As there are some circumstances than can degrade the GNSS signals, especially in a harsh environment like a greenhouse, an adaptive configuration of the Augmented Monte Carlo Localization (AMCL) based in GNSS quality indicators is proposed. The open sky data collected has been used to check the behavior of the proposed approach simulating gaps in the GNSS signals and the results show that this localization subsystem can deal with these outages maintaining the position solution close to the system specifications.
{"title":"Adaptive Localization Configuration for Autonomous Scouting Robot in a Harsh Environment","authors":"David Obregón, Raúl Arnau, María Campo-Cossio, Alejandro Nicolás, M. Pattinson, Smita Tiwari, Ander Ansuategi, C. Tubío, Joaquin Reyes","doi":"10.23919/ENC48637.2020.9317366","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317366","url":null,"abstract":"Greenpatrol project aims to develop a robotic prototype for pest detection and treatment in greenhouse crops. The robot platform uses a sensor fusion approach with Global Navigation Satellite System (GNSS), odometers, inertial and range sensors in order to obtain a position and heading solution with the required precision to navigate inside the greenhouse and to localize accurately the pests. Previously some tests were carried out inside a greenhouse to verify its localization subsystem performance, but due to the difficulties to get a reliable ground truth, additional tests in open sky conditions has been done. As there are some circumstances than can degrade the GNSS signals, especially in a harsh environment like a greenhouse, an adaptive configuration of the Augmented Monte Carlo Localization (AMCL) based in GNSS quality indicators is proposed. The open sky data collected has been used to check the behavior of the proposed approach simulating gaps in the GNSS signals and the results show that this localization subsystem can deal with these outages maintaining the position solution close to the system specifications.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"538 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123245825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317403
M. Mäkelä, Jesperi Rantanen, Julian Ilinea, M. Kirkko-Jaakkola, S. Kaasalainen, L. Ruotsalainen
Cooperative navigation enhances localization performance and situational awareness in challenging conditions, such as in tactical and first responder operations. In this work we demonstrate how the waveform of the Ultra Wideband (UWB) signal used for ranging in cooperative navigation can also be used to detect the environment surrounding the user of the navigation system. Different environments affect the wave-form in different ways, and thus the received waveform contains features characteristic to the environment around the receiver. We show how the received UWB signal waveform can be used in a Convolutional Neural Network (CNN) in order to determine whether the user is outdoors, indoors or in a forest. The environment is recognized correctly more than 90% of the time.
{"title":"Cooperative Environment Recognition Utilizing UWB Waveforms and CNNs","authors":"M. Mäkelä, Jesperi Rantanen, Julian Ilinea, M. Kirkko-Jaakkola, S. Kaasalainen, L. Ruotsalainen","doi":"10.23919/ENC48637.2020.9317403","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317403","url":null,"abstract":"Cooperative navigation enhances localization performance and situational awareness in challenging conditions, such as in tactical and first responder operations. In this work we demonstrate how the waveform of the Ultra Wideband (UWB) signal used for ranging in cooperative navigation can also be used to detect the environment surrounding the user of the navigation system. Different environments affect the wave-form in different ways, and thus the received waveform contains features characteristic to the environment around the receiver. We show how the received UWB signal waveform can be used in a Convolutional Neural Network (CNN) in order to determine whether the user is outdoors, indoors or in a forest. The environment is recognized correctly more than 90% of the time.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127226658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317529
H. Tran, Wei Cao, M. Reutemann, L. Dai, R. Ostermeier, G. Kormann
This paper first introduces the challenges that modern agriculture is facing, followed by a brief description of the evolution of agriculture from precision farming to digital farming. The foundational role of GNSS playing in digital farming is outlined and an example of GNSS applications in precision farming is described.
{"title":"GNSS Positioning and Navigation - A Foundational Element of Digital Farming","authors":"H. Tran, Wei Cao, M. Reutemann, L. Dai, R. Ostermeier, G. Kormann","doi":"10.23919/ENC48637.2020.9317529","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317529","url":null,"abstract":"This paper first introduces the challenges that modern agriculture is facing, followed by a brief description of the evolution of agriculture from precision farming to digital farming. The foundational role of GNSS playing in digital farming is outlined and an example of GNSS applications in precision farming is described.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126642012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317320
N. V. Hien, Gianluca Falco, E. Falletti, M. Nicola, The Vinh La
This paper presents the development of a new metric to improve the performance of the Dispersion of Double Differences (D3) algorithm, which detects GNSS spoofing attacks with a dual-antenna system. The new metric is based on a linear regression applied to the fractional phase double differences. The original D3 algorithm is sometimes prone to false alarms and to missed detections. The idea presented in this paper intends to overcome such limitations by leveraging on the fact that the fractional double differences are characterized by having a piecewise linear trend, with different slopes and intercepts. By evaluating the dispersion of such two parameters instead of the double difference measurements directly, it is possible to design a more robust spoofing detector. The performance of this linear regression-based method is very promising, since no cases of false alarms or of missed detections have been observed in all the performed tests.
{"title":"A Linear Regression Model of the Phase Double Differences to Improve the D3 Spoofing Detection Algorithm","authors":"N. V. Hien, Gianluca Falco, E. Falletti, M. Nicola, The Vinh La","doi":"10.23919/ENC48637.2020.9317320","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317320","url":null,"abstract":"This paper presents the development of a new metric to improve the performance of the Dispersion of Double Differences (D3) algorithm, which detects GNSS spoofing attacks with a dual-antenna system. The new metric is based on a linear regression applied to the fractional phase double differences. The original D3 algorithm is sometimes prone to false alarms and to missed detections. The idea presented in this paper intends to overcome such limitations by leveraging on the fact that the fractional double differences are characterized by having a piecewise linear trend, with different slopes and intercepts. By evaluating the dispersion of such two parameters instead of the double difference measurements directly, it is possible to design a more robust spoofing detector. The performance of this linear regression-based method is very promising, since no cases of false alarms or of missed detections have been observed in all the performed tests.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126509849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317505
K. Smarsly, Mahsa Mirboland
Intelligent transportation systems, coupling information, communication and sensor technologies, aim to improve traffic safety and energy efficiency, while reducing traffic congestion and air pollution. To meet the challenges of the 21st century in the field of road transport, simulation platforms are receiving increasing attention, in an attempt to advance intelligent transportation system (ITS) optimization. Although a plethora of simulation platforms for intelligent transportation systems exist, formalism have not yet been reported that ensure reliable data exchange among different ITS simulation platforms. This paper presents a conceptual model serving as a formal basis for designing ITS simulation platforms for roads based on building information modeling (BIM), which is a method mandated in many European countries when designing and building public infrastructure. In this paper, an extension of the current BIM standard, the Industry Foundation Classes (IFC) schema, is proposed, enabling standard-compliant, BIM-based simulation of intelligent transportation systems for roads. First, the conceptual model is presented, serving as a basis for the IFC schema extension. Then, the IFC schema extension is described and verified with the test software of the official IFC certification program. Next, an illustrative BIM-based simulation scenario is presented for validating the IFC schema extension. The paper concludes with a summary and an outlook on potential future research.
{"title":"BIM-based simulation of intelligent transportation systems","authors":"K. Smarsly, Mahsa Mirboland","doi":"10.23919/ENC48637.2020.9317505","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317505","url":null,"abstract":"Intelligent transportation systems, coupling information, communication and sensor technologies, aim to improve traffic safety and energy efficiency, while reducing traffic congestion and air pollution. To meet the challenges of the 21st century in the field of road transport, simulation platforms are receiving increasing attention, in an attempt to advance intelligent transportation system (ITS) optimization. Although a plethora of simulation platforms for intelligent transportation systems exist, formalism have not yet been reported that ensure reliable data exchange among different ITS simulation platforms. This paper presents a conceptual model serving as a formal basis for designing ITS simulation platforms for roads based on building information modeling (BIM), which is a method mandated in many European countries when designing and building public infrastructure. In this paper, an extension of the current BIM standard, the Industry Foundation Classes (IFC) schema, is proposed, enabling standard-compliant, BIM-based simulation of intelligent transportation systems for roads. First, the conceptual model is presented, serving as a basis for the IFC schema extension. Then, the IFC schema extension is described and verified with the test software of the official IFC certification program. Next, an illustrative BIM-based simulation scenario is presented for validating the IFC schema extension. The paper concludes with a summary and an outlook on potential future research.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114651795","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317375
A. Lamm, J. Möller, A. Hahn
The safe navigation of vessels at sea requires a detailed awareness of possible hazard situations. This work, presents a method to analyze and assess the collision risk considering conditions like bad visibility and rough seas in addition to the risk measurement for risk assessment and near miss detection. For an objective assessment of the current subjective perception of encounter situations, the empirical evaluation of historical observation data of the German coast forms the basis. A process for the extraction and analysis of vessel encounter situations from traffic, weather and chart data forms the basis. Finally, the method will be evaluated in terms of well-definedness, validity, objectiveness and applicability.
{"title":"Collision Risk Model for Encounter Situation Assessment Based on Empirical Observations","authors":"A. Lamm, J. Möller, A. Hahn","doi":"10.23919/ENC48637.2020.9317375","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317375","url":null,"abstract":"The safe navigation of vessels at sea requires a detailed awareness of possible hazard situations. This work, presents a method to analyze and assess the collision risk considering conditions like bad visibility and rough seas in addition to the risk measurement for risk assessment and near miss detection. For an objective assessment of the current subjective perception of encounter situations, the empirical evaluation of historical observation data of the German coast forms the basis. A process for the extraction and analysis of vessel encounter situations from traffic, weather and chart data forms the basis. Finally, the method will be evaluated in terms of well-definedness, validity, objectiveness and applicability.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114709428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317343
C. Doer, G. Trommer
Accurate localization in visually degraded and GNSS denied environments is key for autonomous robotics. Vision based approaches usually fail in challenging conditions like smoke, dusk, direct sunlight or darkness. Our approach uses an Inertial Measurement Unit (IMU) and a millimeter wave FMCW radar sensor as both sensors are not affected by such conditions. A filter based 3D Radar Inertial Odometry (RIO) approach is presented which enables the online estimation of the extrinsic calibration of the radar sensor. Consequently, tedious calibration is not required any more. The application of stochastic cloning enables to process delayed radar measurements properly which enables to apply the navigation filter for online navigation. The proposed system is evaluated in simulation which proves a consistent estimation. Real world experiments with carried datasets and UAV flights prove the improvement by online calibration resulting in reduced position errors.
{"title":"Radar Inertial Odometry With Online Calibration","authors":"C. Doer, G. Trommer","doi":"10.23919/ENC48637.2020.9317343","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317343","url":null,"abstract":"Accurate localization in visually degraded and GNSS denied environments is key for autonomous robotics. Vision based approaches usually fail in challenging conditions like smoke, dusk, direct sunlight or darkness. Our approach uses an Inertial Measurement Unit (IMU) and a millimeter wave FMCW radar sensor as both sensors are not affected by such conditions. A filter based 3D Radar Inertial Odometry (RIO) approach is presented which enables the online estimation of the extrinsic calibration of the radar sensor. Consequently, tedious calibration is not required any more. The application of stochastic cloning enables to process delayed radar measurements properly which enables to apply the navigation filter for online navigation. The proposed system is evaluated in simulation which proves a consistent estimation. Real world experiments with carried datasets and UAV flights prove the improvement by online calibration resulting in reduced position errors.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121763343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-11-23DOI: 10.23919/ENC48637.2020.9317504
S. Averin, A. Gapon, Pavel Ignatev
A paper describes a novel approach to computing DGNSS solution when multi-GNSS measurement observables are available. The approach is applicable to situations when not all the GNSS observables are accompanied with DGNSS corrections. A commonly used “classical” recommendation for such cases is to discard observables which do not have corrections. However, in challenging conditions like urban canyon this recommendation might lead to a case, when such “correct” DGNSS solution might be of poorer quality than the stand-alone one. This is especially true for SBAS, as all operating systems broadcast GPS-only corrections, while user receiver might be capable of tracking signals of GLONASS, Beidou, GALILEO, NavIC in addition to GPS. The suggested in the paper approach is based on rather straightforward methodology, according to which all observables are divided by groups, depending on GNSS type and correction data availability. In the process of computing the position several new unknowns are introduced - one for every group, to estimate clock offsets associated with every group. This approach is implemented in the newest firmware of Topcon receiver boards, which is going to be released soon. The paper provides positioning algorithm's description and results, demonstrating benefits of the suggested approach over the “classical” one. In addition, a paper touches a problem of necessity to revise a definition of “DGNSS mode”, as today there is no term for designating a solution, computed with a mixture of corrected and uncorrected observables.
{"title":"Multi-Constellation DGNSS - A Time to Revise Definitions","authors":"S. Averin, A. Gapon, Pavel Ignatev","doi":"10.23919/ENC48637.2020.9317504","DOIUrl":"https://doi.org/10.23919/ENC48637.2020.9317504","url":null,"abstract":"A paper describes a novel approach to computing DGNSS solution when multi-GNSS measurement observables are available. The approach is applicable to situations when not all the GNSS observables are accompanied with DGNSS corrections. A commonly used “classical” recommendation for such cases is to discard observables which do not have corrections. However, in challenging conditions like urban canyon this recommendation might lead to a case, when such “correct” DGNSS solution might be of poorer quality than the stand-alone one. This is especially true for SBAS, as all operating systems broadcast GPS-only corrections, while user receiver might be capable of tracking signals of GLONASS, Beidou, GALILEO, NavIC in addition to GPS. The suggested in the paper approach is based on rather straightforward methodology, according to which all observables are divided by groups, depending on GNSS type and correction data availability. In the process of computing the position several new unknowns are introduced - one for every group, to estimate clock offsets associated with every group. This approach is implemented in the newest firmware of Topcon receiver boards, which is going to be released soon. The paper provides positioning algorithm's description and results, demonstrating benefits of the suggested approach over the “classical” one. In addition, a paper touches a problem of necessity to revise a definition of “DGNSS mode”, as today there is no term for designating a solution, computed with a mixture of corrected and uncorrected observables.","PeriodicalId":157951,"journal":{"name":"2020 European Navigation Conference (ENC)","volume":"108 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115624216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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