Journal of Geodetic Science最新文献_第3页

Quality control of SIRGAS ZTD products sigasztd产品的质量控制

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0136

M. Mackern, M. L. Mateo, M. F. Camisay, P. Rosell

{"title":"Quality control of SIRGAS ZTD products","authors":"M. Mackern, M. L. Mateo, M. F. Camisay, P. Rosell","doi":"10.1515/jogs-2022-0136","DOIUrl":"https://doi.org/10.1515/jogs-2022-0136","url":null,"abstract":"Abstract The SIRGAS-CON network currently has more than 450 continuous GNSS stations, and it is used for geodetic purposes. In atmospheric studies, it is used for ionospheric monitoring and for the estimation of zenith tropospheric delays (ZTDs). From the Neutral Atmosphere Analysis Center of SIRGAS, Centro de Ingeniería Mendoza Argentina, the final tropospheric products of this network are generated after several stages of quality controls and filtering, in order to be published on a daily basis in the official website of SIRGAS, since 2014 (https://sirgas.ipgh.org/en/products/tropospheric-delays). These products arise from adjusting the solutions estimated by different SIRGAS analysis centers. Prior to the combination, a quality control of the individual solutions is carried out, based on the precision estimator of each parameter and an internal control of each solution with respect to the combined value. In this work, we show the quality control process of the inputs, the selected tolerance and its justification. The internal consistency analysis of tropospheric parameters for a period of 7 years was carried out. We also exposed the improvements in the estimation of tropospheric parameters implemented during 2021 and its impact in the generation of the final ZTD products (in 99% of the stations the mean standard deviation of ZTD is less than 1 mm).","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81934967","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}

引用次数: 1

Assessment of SIRGAS-CON tropospheric products using ERA5 and IGS 利用ERA5和IGS评估SIRGAS-CON对流层产品

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0144

A. Prado, Telmo Vieira, M. Fernandes

{"title":"Assessment of SIRGAS-CON tropospheric products using ERA5 and IGS","authors":"A. Prado, Telmo Vieira, M. Fernandes","doi":"10.1515/jogs-2022-0144","DOIUrl":"https://doi.org/10.1515/jogs-2022-0144","url":null,"abstract":"Abstract Zenith Tropospheric Delays (ZTDs) are used to correct tropospheric effects that cause a delay in the signal measured by Global Navigation Satellite Systems (GNSS) receivers and obtain accurate measurements. ZTD can be estimated from GNSS processing, which means they may suffer from occasional or systematic errors. Therefore, it is necessary to assess the quality and stability of these data over time, since ZTDs are used in several applications that require centimeter precision. Within this context, this work aims to assess the available ZTD of the whole Geodetic Reference System for the Americas Continuously Operating Network (SIRGAS-CON), consisting of 467 stations, spanning the period from January 2014 to December 2020 using the most recent Numerical Weather Model ERA5 from the European Centre for Medium-Range Weather Forecasts and common stations to the International GNSS Service (IGS) for an intercomparison. Results show that 10% of the stations present some instability, such as periods of highly dispersed data or discontinuities, with more occurrence in stations located in Argentina, Uruguay and Colombia. The remaining 90% proved to have stable and reliable ZTD, both in comparison with ERA5 and IGS.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90854850","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}

引用次数: 2

Analysis of high-resolution global gravity field models for the estimation of International Height Reference System (IHRS) coordinates in Argentina 阿根廷用于估算国际高度参考系统(IHRS)坐标的高分辨率全球重力场模型分析

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0139

C. Tocho, Ezequiel D. Antokoletz, Agustín R. Gómez, H. Guagni, D. Piñón

{"title":"Analysis of high-resolution global gravity field models for the estimation of International Height Reference System (IHRS) coordinates in Argentina","authors":"C. Tocho, Ezequiel D. Antokoletz, Agustín R. Gómez, H. Guagni, D. Piñón","doi":"10.1515/jogs-2022-0139","DOIUrl":"https://doi.org/10.1515/jogs-2022-0139","url":null,"abstract":"Abstract Following the definition and realization of the International Height Reference System (IHRS), the vertical coordinate of a given point at the Earth’s surface can be obtained from the computation of the geopotential value from a harmonic expansion of a Global Gravity Model of High-Resolution (GGM-HR) or based on the computation of a local or regional pure gravimetric geoid or quasigeoid. Therefore, an evaluation of the accuracy of GGMs-HR and the geoid model available is needed in order to assess its capability to infer IHRS coordinates. In this study, different GGMs-HR are evaluated against 2287 benchmarks in Argentina. Moreover, the most recent geoid model of Argentina is also evaluated. Geoid undulations at these benchmarks are obtained based on ellipsoidal and orthometric heights in the local vertical datum. Results suggest that among the evaluated GGMs-HR, XGM2019e provides the best agreement with the observed geoid heights, but none of them is accurate enough in order to infer vertical coordinates in the IHRS. Similar conclusions are obtained for the local geoid model for Argentina demonstrating the necessity for a more precise geoid model, following the standards and recommendations given for the IHRS.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84771073","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}

引用次数: 0

Analysis of the gravity field, direct and inverse problems, by Fernando Sanso and Daniele Sampietro published by Birkhäuser 2022 重力场的分析，直接和反问题，费尔南多·桑索和丹尼尔·桑皮耶特罗发表于Birkhäuser 2022

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0149

M. Eshagh

引用次数: 1

SIRGAS reference frame analysis at DGFI–TUM DGFI-TUM的SIRGAS参考帧分析

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0138

L. Sánchez, H. Drewes, A. Kehm, M. Seitz

{"title":"SIRGAS reference frame analysis at DGFI–TUM","authors":"L. Sánchez, H. Drewes, A. Kehm, M. Seitz","doi":"10.1515/jogs-2022-0138","DOIUrl":"https://doi.org/10.1515/jogs-2022-0138","url":null,"abstract":"Abstract The Deutsches Geodätisches Forschungsinstitut (DGFI) has been involved in the research activities of the Latin American Reference Frame SIRGAS since its establishment in 1993. DGFI coordinated the SIRGAS Global Positioning System campaigns of 1995 and 2000 and acted as an analysis centre of both campaigns contributing to the first two SIRGAS realisations known as SIRGAS95 and SIRGAS2000. In 1996, DGFI established the Regional Network Associate Analysis Centre for SIRGAS of the International GNSS (Global Navigation Satellite System) Service (IGS RNAAC SIRGAS) and took on responsibility for processing the SIRGAS continuously operating stations and generating weekly position solutions. Later followed the determination of cumulative (multi-year) solutions, consisting of station positions and constant velocities, providing accurate solutions for the SIRGAS reference frame. DGFI was integrated into the Technical University of Munich (TUM) in 2015, becoming DGFI–TUM, and based on the SIRGAS operational analyses, it continues investigating strategies to guarantee the reliability of the reference frame through time. This includes the estimation of the reference frame kinematics, evaluation, modelling, and reduction of seismic and post-seismic deformations on the reference frame, and modelling crustal kinematics in the SIRGAS region by continuous velocity models. This article summarises analysis strategies and science data products developed by DGFI–TUM as a SIRGAS analysis centre and as the IGS RNAAC SIRGAS. Special care is given to the determination of the most recent SIRGAS reference frame solution called SIRGAS2022, which is based on the second SIRGAS reprocessing campaign performed by DGFI–TUM to obtain homogeneously computed SIRGAS daily and weekly station position solutions referring to the IGS reference frame IGS14/IGb14 since January 2000.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87168334","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}

引用次数: 3

Geoid model validation and topographic bias 大地水准面模型验证和地形偏差

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0133

L. Sjöberg

引用次数: 0

Shipborne GNSS acquisition of sea surface heights in the Baltic Sea 波罗的海海面高度的船载GNSS采集

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0131

A. Liibusk, Sander Varbla, A. Ellmann, K. Vahter, R. Uiboupin, N. Delpeche-Ellmann

{"title":"Shipborne GNSS acquisition of sea surface heights in the Baltic Sea","authors":"A. Liibusk, Sander Varbla, A. Ellmann, K. Vahter, R. Uiboupin, N. Delpeche-Ellmann","doi":"10.1515/jogs-2022-0131","DOIUrl":"https://doi.org/10.1515/jogs-2022-0131","url":null,"abstract":"Abstract For determining precise sea surface heights, six marine GNSS (global navigation satellite system) survey campaigns were performed in the eastern Baltic Sea in 2021. Four GNSS antennas were installed on the vessel, the coordinates of which were computed relative to GNSS–CORS (continuously operating reference stations). The GNSS–CORS results are compared to the PPP (precise point positioning)-based results. Better accuracy is associated with the GNSS–CORS postprocessed points; however, the PPP approach provided more accurate results for longer than 40 km baselines. For instance, the a priori vertical accuracy of the PPP solution is, on average, 0.050 ± 0.006 m and more stable along the entire vessel’s survey route. Conversely, the accuracy of CORS-based solutions decreases significantly when the distances from the GNSS–CORS exceed 40 km, whereas the standard deviation between the CORS and PPP-based solutions is up to 0.075 m in these sections. Note that in the harbor (about 4 km from the nearest GNSS–CORS), the standard deviation of vertical differences between the two solutions remains between 0.013 and 0.024 m. In addition, the GNSS antennas situated in different positions on the vessel indicated different measurement accuracies. It is suggested for further studies that at least one GNSS antenna should be mounted above the mass center of the vessel to reduce the effects of the dominating pitch motion during the surveys.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87493483","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}

引用次数: 2

Introducing covariances of observations in the minimum L1-norm, is it needed? 在最小l1范数中引入观测值的协方差，需要吗?

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0135

S. Suraci, L. Oliveira, I. Klein, R. Goldschmidt

{"title":"Introducing covariances of observations in the minimum L1-norm, is it needed?","authors":"S. Suraci, L. Oliveira, I. Klein, R. Goldschmidt","doi":"10.1515/jogs-2022-0135","DOIUrl":"https://doi.org/10.1515/jogs-2022-0135","url":null,"abstract":"Abstract The most common approaches for assigning weights to observations in minimum L1-norm (ML1) is to introduce weights of p or p sqrt{p} , p being the weights vector of observations given by the inverse of variances. Hence, they do not take covariances into consideration, being appropriated only to independent observations. To work around this limitation, methods for decorrelation/unit-weight reduction of observations originally developed in the context of least squares (LS) have been applied for ML1, although this adaptation still requires further investigations. In this article, we presented a deeper investigation into the mentioned adaptation and proposed the new ML1 expressions that introduce weights for both independent and correlated observations; and compared their results with the usual approaches that ignore covariances. Experiments were performed in a leveling network geometry by means of Monte Carlo simulations considering three different scenarios: independent observations, observations with “weak” correlations, and observations with “strong” correlations. The main conclusions are: (1) in ML1 adjustment of independent observations, adaptation of LS techniques introduces weights proportional to p sqrt{p} (but not p); (2) proposed formulations allowed covariances to influence parameters estimation, which is unfeasible with usual ML1 formulations; (3) introducing weighs of p provided the closest ML1 parameters estimation compared to that of LS in networks free of outliers; (4) weighs of p sqrt{p} provided the highest successful rate in outlier identification with ML1. Conclusions (3) and (4) imply that introducing covariances in ML1 may adversely affect its performance in these two practical applications.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86352708","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}

引用次数: 1

Spatial resolution of airborne gravity estimates in Kalman filtering 卡尔曼滤波中航空重力估计的空间分辨率

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0143

T. Jensen

{"title":"Spatial resolution of airborne gravity estimates in Kalman filtering","authors":"T. Jensen","doi":"10.1515/jogs-2022-0143","DOIUrl":"https://doi.org/10.1515/jogs-2022-0143","url":null,"abstract":"Abstract Airborne gravimetry is an efficient and reliable method to obtain information on the gravity field, fundamental to gravity field modelling, geoid determination, and flood risk mapping. In evaluation and utilization of gravity estimates, two measures are of fundamental importance, namely the accuracy and spatial resolution. These measures are related to one another through the filtering required to suppress observational noise. As strapdown inertial measurement units (IMUs) are increasingly deployed for airborne gravity surveys, the Kalman filter estimation method is routinely used for gravity determination. Since filtering is not applied directly to the observations in Kalman filtering, it is not straightforward to associate the derived gravity estimates with a measure of spatial resolution. This investigation presents a method for deriving spatial resolution by evaluating the transfer function formed after applying a delta function to the observed accelerations. The method is applied to Kalman-filter-derived gravity estimates from an airborne strapdown IMU system, yielding a full-wavelength spatial resolution of 5.5 km at an accuracy of 0.6 mGal. These results are consistent with a comparison with upward continued terrestrial gravity observations.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89744014","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}

引用次数: 0

Developing low-cost automated tool for integrating maps with GNSS satellite positioning data 开发低成本的自动化工具，将地图与GNSS卫星定位数据相结合

IF 1.3

Journal of Geodetic Science Pub Date : 2022-01-01 DOI: 10.1515/jogs-2022-0134

M. Habib, Ali Farghal, A. Taani

{"title":"Developing low-cost automated tool for integrating maps with GNSS satellite positioning data","authors":"M. Habib, Ali Farghal, A. Taani","doi":"10.1515/jogs-2022-0134","DOIUrl":"https://doi.org/10.1515/jogs-2022-0134","url":null,"abstract":"Abstract Representing the Earth’s physical features onto a flat surface is a critical and challenging issue for geodesists to build topographic mappings at field scale in various applications. Artificial satellite positioning data are currently defined on a global geocentric frame, while terrestrial geodetic networks are determined on a local ellipsoid. Hence, coordinate transformations in three-dimensional space are required for data fusion involving different coordinate systems utilizing common points in two sets of coordinates. On the other hand, small companies in many developing countries have some data conversion difficulties due to the need for high-cost software and qualified persons. A low-cost automated tool is helpful in achieving this task and ensuring quality and positional accuracy. In this investigation, the problem was undertaken by establishing a software tool in the Microsoft Visual Studio environment for map-matching with global coordinates based on similarity transformations and a conformal polynomial approach. The tool’s performance was evaluated through a numerical example to assign transformation parameters and derive coordinates of checkpoints from the prediction surface.","PeriodicalId":44569,"journal":{"name":"Journal of Geodetic Science","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87095195","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}

引用次数: 1