The methods for processing and storage of data in global navigation satellite systems for the task of perimeter protection

The methods for processing and storage of GNSS data for the task of perimeter protection are described. The article proposes a basic algorithm for the operation of a GNSS data collection, processing and storage system that allows you to track processed GNSS data on a remote web service in public formats, as well as send signals through a client mobile application to available platforms and systems about temporarily suspending or canceling GNSS data recording.

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Assessment of the Cutting Performance of a Robot Mower Using Custom Built Software

Agronomy ◽

10.3390/agronomy9050230 ◽

2019 ◽

Vol 9 (5) ◽

pp. 230 ◽

Cited By ~ 4

Author(s):

Luisa Martelloni ◽

Marco Fontanelli ◽

Stefano Pieri ◽

Christian Frasconi ◽

Lisa Caturegli ◽

...

Keyword(s):

Autonomous Vehicles ◽

Global Navigation Satellite Systems ◽

Forward Speed ◽

Satellite Systems ◽

Different Shapes ◽

Global Navigation Satellite ◽

High Level ◽

Short Time ◽

Gnss Data ◽

Collection And Management

Before the introduction of positioning technologies in agriculture practices such as global navigation satellite systems (GNSS), data collection and management were time-consuming and labor-intensive tasks. Today, due to the introduction of advanced technologies, precise information on the performance of agricultural machines, and smaller autonomous vehicles such as robot mowers, can be collected in a relatively short time. The aim of this work was to track the performance of a robot mower in various turfgrass areas of an equal number of square meters but with four different shapes by using real-time kinematic (RTK)-GNSS devices, and to easily extract data by a custom built software capable of calculating the distance travelled by the robot mower, the forward speed, the cutting area, and the number of intersections of the trajectories. These data were then analyzed in order to provide useful functioning information for manufacturers, entrepreneurs, and practitioners. The path planning of the robot mower was random and the turfgrass area for each of the four shapes was 135 m2 without obstacles. The distance travelled by the robot mower, the mean forward speed, and the intersections of the trajectories were affected by the interaction between the time of cutting and the shape of the turfgrass. For all the different shapes, the whole turfgrass area was completely cut after two hours of mowing. The cutting efficiency decreased by increasing the time, as a consequence of the increase in overlaps. After 75 minutes of cutting, the efficiency was about 35% in all the turfgrass areas shapes, thus indicating a high level of overlapping.

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Experimental estimation of GNSS performances at the national aviation university

E3S Web of Conferences ◽

10.1051/e3sconf/202016403052 ◽

2020 ◽

Vol 164 ◽

pp. 03052

Author(s):

Volodymir Kharchenko ◽

Valeriy Konin ◽

Olexiy Pogurelsky ◽

Ekaterina Stativa

Keyword(s):

Experimental Data ◽

Continuous Monitoring ◽

Goal Achievement ◽

Global Navigation Satellite Systems ◽

Reference Station ◽

Satellite Systems ◽

Systems Quality ◽

Primary Focus ◽

Global Navigation Satellite ◽

Gnss Data

The goal of the research is to develop a of Global Navigation Satellite Systems quality monitoring methodology based on available equipment in the satellite navigation laboratory of the National Aviation University (Kyiv, Ukraine). For successful the goal achievement it is necessary to solve follow list of tasks: to determine the composition of the necessary equipment and order of it installing and connection; to develop the necessary software for processing received GNSS data; to estimate the GNSS characteristics with the help of experimental data. The primary focus of this research is on the following characteristics: accuracy (in terms of deviation coordinates in horizontal and vertical planes from the coordinates of the reference station and numerical values in meters); integrity information (summarized in the form of horizontal and Stanford plots); overall availability of service – measured as the availability of signals meeting the requirements for instrumented approaches with vertical guidance (APV) APV-1, APV-2, and Category 1 (CAT-1) precision approaches to runways. The main result of this research is developing software that could be applied for continuous monitoring of GNSS performances. The possibilities of it were successfully tested with the help of experimental data received from GPS and Galileo satellites.

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Validating HY-2A CMR Precipitable Water Vapor Using Ground-based and Shipborne GNSS Observations

10.5194/amt-2019-503 ◽

2020 ◽

Author(s):

Zhilu Wu ◽

Yanxiong Liu ◽

Yang Liu ◽

Jungang Wang ◽

Xiufeng He ◽

...

Keyword(s):

Water Vapor ◽

Microwave Radiometer ◽

Precipitable Water ◽

Global Navigation Satellite Systems ◽

High Temporal Resolution ◽

Satellite Systems ◽

The Indian Ocean ◽

Global Navigation Satellite ◽

Gnss Data ◽

Gnss Observations

Abstract. The calibration microwave radiometer (CMR) onboard Haiyang-2A satellite provides wet tropospheric delays correction for altimetry data, which can also contribute to the understanding of climate system and weather processes. Ground-based Global Navigation Satellite Systems (GNSS) provide precise PWV with high temporal resolution and could be used for calibration and monitoring of the CMR data, and shipborne GNSS provides accurate PWV over open oceans, which can be directly compared with uncontaminated CMR data. In this study, the HY-2A CMR water vapor product is validated using ground-based GNSS observations of 100 IGS stations along the coastline and 56-day shipborne GNSS observations over the Indian Ocean. The processing strategy for GNSS data and CMR data is discussed in detail. Special efforts were made to the quality control and reconstruction of contaminated CMR data. The validation result shows that HY-2A CMR PWV agrees well with ground-based GNSS PWV with 2.67 mm in RMS within 100 km. Geographically, the RMS is 1.12 mm in the polar region and 2.78 mm elsewhere. The PWV agreement between HY-2A and shipborne GNSS shows a significant correlation with the distance between the ship and the satellite footprint, with an RMS of 1.57 mm for the distance threshold of 100 km. Ground-based GNSS and shipborne GNSS agree with HY-2A CMR well with no obvious system error.

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Towards FAIR GNSS data: challenges and open problems

10.5194/egusphere-egu2020-18398 ◽

2020 ◽

Author(s):

Anna Miglio ◽

Carine Bruyninx ◽

Andras Fabian ◽

Juliette Legrand ◽

Eric Pottiaux ◽

...

Keyword(s):

Research Policy ◽

Global Navigation Satellite Systems ◽

International Gnss Service ◽

Open Problems ◽

Data Repositories ◽

Satellite Systems ◽

Data Practices ◽

Metadata Standards ◽

Global Navigation Satellite ◽

Gnss Data

Nowadays, we measure positions on Earth&#8217;s surface thanks to Global Navigation Satellite Systems (GNSS) e.g. GPS, GLONASS, and Galileo. Activities such as navigation, mapping, and surveying rely on permanent GNSS tracking stations located all over the world. The Royal Observatory of Belgium (ROB) maintains and operates a repository containing data from hundreds of GNSS stations belonging to the European GNSS networks (e.g. EUREF, Bruyninx et al., 2019).&#160;ROB&#8217;s repository contains GNSS data that are openly available and rigorously curated. The curation data include detailed GNSS station descriptions (e.g. location, pictures, and data author) as well as quality indicators of the GNSS observations.However, funders and research policy makers are progressively asking for data to be made Findable, Accessible, Interoperable, and Reusable (FAIR) and therefore to increase data transparency, discoverability, interoperability, and accessibility.In particular, within the GNSS community, there is no shared agreement yet on the need for making data FAIR. Therefore, turning GNSS data FAIR presents many challenges and, although FAIR data has been included in EUREF&#8217;s strategic plan, no practical roadmap has been implemented so far. We will illustrate the specific difficulties and the need for an open discussion including also other communities working on FAIR data.For example, making GNSS data easily findable and accessible would require to attribute persistent identifiers to the data. It is worth noting that the International GNSS Service (IGS) is only now beginning to consider the attribution of DOIs (Digital Object Identifiers) to GNSS data, mainly to allow data citation and acknowledgement of data providers. Some individual GNSS data repositories are using DOIs (such as UNAVCO, USA).&#160; Are DOIs the only available option or are there more suitable types of URIs (Uniform Resource Identifiers) to consider?The GNSS community would greatly benefit from FAIR data practices, as at present, (almost) no licenses have been attributed to GNSS data, data duplication is still an issue, historical provenance information is not available because of data manipulations in data centres, citation of the data providers is far from the rule, etc.To move further along the path towards FAIR GNSS data, one would need to implement standardised metadata models to ensure data interoperability, but, as several metadata standards are already in use in various scientific disciplines, which one to choose?Then, to facilitate the reuse (and long-term preservation) of GNSS data, all metadata should be properly linked to the corresponding data and additional metadata, such as provenance and license information. The latter is a good example up for discussion: despite the fact that &#8216;CC BY&#8217; license is already assigned to some of the GNSS data, other licenses might need to be enabled.&#160;Bruyninx C., Legrand J., Fabian A., Pottiaux E. (2019) &#8220;GNSS Metadata and Data Validation in the EUREF Permanent Network&#8221;. GPS Sol., 23(4), https://doi: 10.1007/s10291-019-0880-9&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;

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Determining the guidance system accuracy with the support of a large GNSS dataset

Research in Agricultural Engineering ◽

10.17221/60/2012-rae ◽

2013 ◽

Vol 59 (Special Issue) ◽

pp. S65-S70 ◽

Cited By ~ 1

Author(s):

V. Rataj ◽

J. Galambošová ◽

M. Vašek

Keyword(s):

Monitoring System ◽

Global Navigation Satellite Systems ◽

Guidance System ◽

Rectangular Coordinate System ◽

Projection System ◽

Satellite Systems ◽

Ideal Line ◽

Guidance Systems ◽

Global Navigation Satellite ◽

Gnss Data

Several methods are used presently to assess the accuracy of machinery guidance systems. However, these offer a limited number of records and are time and cost consuming. As the machinery is often equipped with a monitoring system for the management purposes, these data can be used. The aim of this work was to develop and verify a method to determine the accuracy of the machinery guidance systems based on a large dataset obtained from the machinery monitoring system. The proposed method uses the transformation of global navigation satellite systems (GNSS) data into a rectangular coordinate system SJTSK (National projection system – Krovak projection). Based on the geometry principle, the ideal line can be determined, and afterwards, the off-track error of each actual position can be calculated. After the verification of this method, it can be concluded that it brings benefits in terms of further use of the data from the monitoring systems, the estimation of the error based on a robust dataset, elimination of subjective and measurement method errors, as well as spatial localisation of the off-track errors at the field.

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Linear and Nonlinear Deformation Effects in the Permanent GNSS Network of Cyprus

Sensors ◽

10.3390/s20061768 ◽

2020 ◽

Vol 20 (6) ◽

pp. 1768

Author(s):

Chris Danezis ◽

Miltiadis Chatzinikos ◽

Christopher Kotsakis

Keyword(s):

Crustal Deformation ◽

Global Navigation Satellite Systems ◽

Satellite Systems ◽

Time Period ◽

Position Time Series ◽

Gnss Receivers ◽

Linear And Nonlinear ◽

Gnss Network ◽

Global Navigation Satellite ◽

Gnss Data

Permanent Global Navigation Satellite Systems (GNSS) reference stations are well established as a powerful tool for the estimation of deformation induced by man-made or physical processes. GNSS sensors are successfully used to determine positions and velocities over a specified time period, with unprecedented accuracy, promoting research in many safety-critical areas, such as geophysics and geo-tectonics, tackling problems that torment traditional equipment and providing deformation products with absolute accuracy. Cyprus, being located at the Mediterranean fault, exhibits a very interesting geodynamic regime, which has yet to be investigated thoroughly. Accordingly, this research revolves around the estimation of crustal deformation in Cyprus using GNSS receivers. CYPOS (CYprus POsitioning System), a network of seven permanent GNSS stations has been operating since 2008, under the responsibility of the Department of Lands and Surveys. The continuous flow of positioning data collected over this network, offers the required information to investigate the behavior of the crustal deformation field of Cyprus using GNSS sensors for the first time. This paper presents the results of a multi-year analysis (11/2011–01/2017) of daily GNSS data and provides inferences of linear and nonlinear deforming signals into the position time series of the network stations. Specifically, 3D station velocities and seasonal periodic displacements are jointly estimated and presented via a data stacking approach with respect to the IGb08 reference frame.

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The Greenland Geodetic Network (GNET)

10.5194/egusphere-egu2020-1785 ◽

2020 ◽

Author(s):

Kelly Brunt ◽

Robert Hawley

Keyword(s):

National Science Foundation ◽

Geodetic Network ◽

Global Navigation Satellite Systems ◽

Data Transport ◽

Satellite Systems ◽

International Collaborations ◽

National Science ◽

Long Time ◽

Global Navigation Satellite ◽

Gnss Data

The Greenland Geodetic Network (GNET) consists of 58 global navigation satellite systems (GNSS) installed on the bedrock around the perimeter of the island. Much of the network was installed between 2007 and 2009, providing a long time series of GNSS data for much of Greenland. The network is currently owned and maintained by the Danish Agency for Data Supply and Efficiency (SDFE), while the National Science Foundation (NSF) provides support for data transport from the deep field. Here, we present a new resource (go-gnet.org) intended to be a clearinghouse to foster international collaborations and to encourage new and innovative use of these data.

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Determation of the ionospheric observable and short-term variations of receiver DCBs using modified carrier‑to‑code leveling method with multi-frequency and multi-GNSS data

10.5194/egusphere-egu2020-20967 ◽

2020 ◽

Author(s):

Min Li ◽

Baocheng Zhang ◽

Xiao Zhang

Keyword(s):

Rapid Development ◽

Full Rank ◽

Global Navigation Satellite Systems ◽

Dual Frequency ◽

Short Term ◽

Frequency Model ◽

Satellite Systems ◽

Triple Frequency ◽

Global Navigation Satellite ◽

Gnss Data

When sensing the Earth&#8217;s ionosphere using pseudorange observations of global navigation satellite systems (GNSS), the satellite and receiver Differential Code Biases (DCBs) account for one of the main sources of error. For the sake of convenience, Receiver DCBs (DCBs) are commonly assumed as constants over a period of one day in the traditional carrier-to-code leveling (CCL) method. Thus, remarkable intraday variability in the receiver DCBs have been ignored in the commonly-used assumption and may seriously restrict the accuracy of ionospheric observable retrieval. The Modified CCL (MCCL) method can eliminate the adverse impact of the short-term variations of RDCBs on the retrieval of ionospheric TEC. With the rapid development of the GPS, GLONASS, Galileo and BeiDou systems, there is a strong demand of precise ionospheric TEC products for multiple constellations and frequencies. Considering the existed MCCL method can only be used for dual-frequency GNSS data, in this study, we extend the two-frequency MCCL method to the multi-frequency and multi-GNSS case and further carry out a series of investigations. In our proposed method, a newly full-rank multi-frequency (more than triple frequency) model with raw observations are established to synchronously estimate both the slant ionospheric delays and the RCB offset with respect to the reference epoch at each individual frequency. Based on the test results, compared to the traditional CCL-method, the accuracy of the ionospheric TEC retrieved using our proposed method can be improved from 5.12 TECu to 0.95 TECu in the case that significant short-term variations existed in receiver DCBs. In addition, the between-epoch fluctuations experienced by receiver code biases at all frequencies tracked by a single receiver can be detected by our the proposed method, and the dependence of multi-GNSS and multi-frequency RDCB offsets upon ambient temperature further are verified in this study. Compared to Galileo system, the RDCB in BDS show higher correlation with temperature. We also found that the RDCB at different frequencies of the same system show various characteristics.

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Kinematic GNSS positioning results compared against Agisoft Metashape and Pix4dmapper results produced in the San Joaquin experimental range in Fresno County, California

Journal of Geodetic Science ◽

10.1515/jogs-2020-0122 ◽

2021 ◽

Vol 11 (1) ◽

pp. 48-57

Author(s):

M. Berber ◽

R. Munjy ◽

J. Lopez

Keyword(s):

Data Processing ◽

Global Navigation Satellite Systems ◽

Kinematic Data ◽

Fresno County ◽

Satellite Systems ◽

Data Processing Software ◽

Recent Developments ◽

Processing Modes ◽

Global Navigation Satellite ◽

Gnss Data

Abstract RTKLIB which is an open source Global Navigation Satellite Systems (GNSS) software has gained rapid acceptance among Surveying professionals thanks to recent developments in UAS (Unmanned Aerial System) technology. RTKLIB enables standard and precise point positioning (PPP) in real-time and post-processing modes to be performed. As such, UAS users utilize this software to analyze GNSS data collected by GNSS systems on UAS. By being versatile and free, RTKLIB is commonly used by many; however, it is not the only freely available GNSS software. There are also freely available online GNSS data processing software running on servers. These online GNSS data processing services provide data processing in static, kinematic and rapid static modes. Because UAS collect data in kinematic mode, in this study, kinematic data processing by aforementioned software (CSRS-PPP, GAPS and APPS) is analyzed. The results coming from these software are compared against the results produced by photogrammetric software (Agisoft Metashape and Pix4Dmapper). The aim of this practical project is to produce generalizable knowledge about the performance of these software. It is found out that RTKLIB and CSRS-PPP achieved cm-level precision. Yet, GAPS and APPS achieved dm-level precision both for horizontal and vertical coordinates. This study demonstrates the precision and accuracy expected from these software if they are used for kinematic GNSS data processing.

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Analysis of October 23 (Mw 7.2) and November 9 (Mw 5.6), 2011 Van Earthquakes Using Long-Term GNSS Time Series

Earth Sciences Research Journal ◽

10.15446/esrj.v21n3.62812 ◽

2017 ◽

Vol 21 (3) ◽

pp. 147-156 ◽

Cited By ~ 3

Author(s):

Ibrahim Tiryakioglu ◽

Hakan Yavasoglu ◽

Mehmet Ali Ugur Ugur ◽

Caglar Ozkaymak ◽

Mustafa Yilmaz ◽

...

Keyword(s):

Time Series ◽

Hanging Wall ◽

Global Navigation Satellite Systems ◽

Satellite Systems ◽

Before And After ◽

Wall Deformation ◽

Van Earthquakes ◽

Global Navigation Satellite ◽

Seismic Deformation ◽

Gnss Data

The eastern Anatolia provides one of the best examples of an area of rapid deformation and intense contraction that is the consequence of an active continental collision between the Arabian and Eurasian plates leading to large and devastating earthquakes. The latest evidence of the active tectonism in the region is revealed by two remarkable seismic events; Van-Tabanli (Mw 7.2, October 23, 2011) and Van-Edremit (Mw 5.6, November 9, 2011) earthquakes. The study of the earthquake cycle and observation of geodetic and seismic deformation in this region is very important to hazard assessments. In this study, the inter-seismic, co-seismic, and post-seismic movements caused by the above-mentioned earthquakes were investigated using the time series of 2300 days of Global Navigation Satellite Systems (GNSS) observations of the local stations selected from the network of the Continuously Operating Reference Stations, Turkey (CORS-TR). For the inter-seismic period, approximately 1100 daily data were obtained from 21 CORS-TR stations (prior to the earthquakes between October 1, 2008 and October 23, 2011) and evaluated using the GAMIT/GLOBK software. The behaviour of these stations was investigated by processing 1 Hz data from the GNSS stations during the earthquakes on the GAMIT/TRACK software. In addition to October 23 and November 9, the GNSS data on one day before and after the earthquakes was assessed to determine co-seismic deformations. During the October 23 earthquake, hanging-wall deformation of about 60 mm was detected in the SW direction at the MURA station. However, at the VAAN station, deformation of 200 mm (value predicted by time series) was observed in the footwall block in the NW direction. There were not any significant changes at the stations during the November 9 earthquake. For the post-seismic period, the GNSS data from 2012 to 2015 was evaluated. According to the observations, post-seismic deformation continued at the stations close to the epicenter of the earthquake.

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