Accuracy of GNSS Methods最新文献

Comparative Study of Some Online GNSS Post-Processing Services at Selected Permanent GNSS Sites in Nigeria 尼日利亚选定永久GNSS站点的一些在线GNSS后处理服务的比较研究

Accuracy of GNSS Methods Pub Date : 2019-01-16 DOI: 10.5772/INTECHOPEN.79924

O. A. Isioye, M. Moses, Lukman Abdulmumin

{"title":"Comparative Study of Some Online GNSS Post-Processing Services at Selected Permanent GNSS Sites in Nigeria","authors":"O. A. Isioye, M. Moses, Lukman Abdulmumin","doi":"10.5772/INTECHOPEN.79924","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.79924","url":null,"abstract":"Many applications in surveying and mapping have been made simpler and more precise due to the advent of GNSS, and thus, the demand for using cutting-edge GNSS techniques in surveying and mapping applications has become indispensable. Online GNSS post- processing services are now available to provide support for users in need of precise point positioning or conventional differential positioning services and without requiring a prior knowledge of GNSS processing software. This study evaluates the performance of some online GNSS facilities with emphasis on observation duration (i.e. 1hr, 2hr, 6hr 12hr and 24hr observations). Three of these online facilities (AUSPOS, GAPS and magic-GNSS) were chosen based on their mode of operation and were evaluated at the location of five permanent GNSS stations in Nigeria. The study cut across two epochs in the year 2014 (i.e. seven days each in the months of January and July). Results in this study indicate that users can expect reliable results from these online services and their accuracy is within allowable limits for mapping applications in Nigeria. The similarity of the results between all of the services used is amazing, thus further demonstrates the robustness of the algorithms and processes employed by the different online facilities.","PeriodicalId":324824,"journal":{"name":"Accuracy of GNSS Methods","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123715487","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: 6

Evaluation Methods of Satellite Navigation System Performance 卫星导航系统性能评价方法

Accuracy of GNSS Methods Pub Date : 2019-01-16 DOI: 10.5772/INTECHOPEN.81034

Ershen Wang, He He, Chaoying Jia

{"title":"Evaluation Methods of Satellite Navigation System Performance","authors":"Ershen Wang, He He, Chaoying Jia","doi":"10.5772/INTECHOPEN.81034","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.81034","url":null,"abstract":"With the development of global satellite navigation system, for example, global position- ing system (GPS) and so on, some regional navigation systems and augmentation systems are developing rapidly. The continuous development of satellite navigation system has attracted the users ’ attention to satellite navigation performance, which makes the navigation system performance become the key of satellite navigation system competition in the field of GNSS applications. The signal in space (SIS) continuity evaluation model based on the reliability is established, and the mean time between failures (MTBF) is used to characterize the probability that there is no continuity loss in unit time. Aiming at the incompleteness of the current availability model, a per-satellite availability evaluation models based on Markov process is established. Moreover, the constellation availability evaluation model is proposed by combining the satellite failure rate, repair rate and backup situation. By analyzing the measured data, the probability of the continuity and availability of GPS and BeiDou Navigation Satellite System (BDS) are calculated respec- tively. The results are instructive for the study of the availability performance monitoring and the evaluation of global BDS.","PeriodicalId":324824,"journal":{"name":"Accuracy of GNSS Methods","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117098036","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

Evaluation of GNSS Data with Internet Based Services: The Case of HRUH Station 基于互联网服务的GNSS数据评估:以HRUH站为例

Accuracy of GNSS Methods Pub Date : 2019-01-16 DOI: 10.5772/INTECHOPEN.79064

M. Ulukavak

引用次数: 0

Introductory Chapter: The Philosophy Behind the Accuracy Assessment of GNSS Methods 导论章:GNSS方法精度评估背后的哲学

Accuracy of GNSS Methods Pub Date : 2018-11-05 DOI: 10.5772/INTECHOPEN.81288

D. U. Sanli

引用次数: 1

Robust GNSS Positioning in Urban Environment 城市环境下稳健的GNSS定位

Accuracy of GNSS Methods Pub Date : 2018-11-05 DOI: 10.5772/INTECHOPEN.80412

Enik Shytermeja

{"title":"Robust GNSS Positioning in Urban Environment","authors":"Enik Shytermeja","doi":"10.5772/INTECHOPEN.80412","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.80412","url":null,"abstract":"In the past years, global navigation satellite systems (GNSS) have gained the core position concerning the geolocalization applications and services in urban environments. The major issue of the GNSS-based urban application expansion is related to the positioning service quality assurance, expressed in terms of accuracy, integrity, availability, and continuity of the localization service. The dense urban environments, such as city centers, are challenging to the GNSS signal reception causing the frequent blockage of the line-of-sight (LOS) signals and the multipath phenomenon, referred to as the reception of the diffracted/reflected echoes of the transmitted signal. These effects severely affect the pseudorange and Doppler measurements, used by a GNSS receiver for the user’s position computation, which will further induce the computation of an erroneous positioning solution by the navigation processor down to a positioning loss in the presence of limited satellite visibility and few provided measurements. Therefore, advanced signal processing techniques do represent viable solutions aiming at the mitigation of these undesired effects in order to foster the accuracy and availability of the localization solution. This chapter will address in details the GNSS vector tracking (VT) receiver’s configuration able to cope with the urban environment-induced effects.","PeriodicalId":324824,"journal":{"name":"Accuracy of GNSS Methods","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115062189","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

Development of Recurrent Method with Rotation for Combined Adjustment of Terrestrial Geodetic and GNSS Networks in National Spatial Reference System 国家空间参照系大地测量网与GNSS网联合平差的旋转循环方法研究

Accuracy of GNSS Methods Pub Date : 2018-11-05 DOI: 10.5772/INTECHOPEN.78770

Ha Minh Hoa

{"title":"Development of Recurrent Method with Rotation for Combined Adjustment of Terrestrial Geodetic and GNSS Networks in National Spatial Reference System","authors":"Ha Minh Hoa","doi":"10.5772/INTECHOPEN.78770","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.78770","url":null,"abstract":"A construction of national spatial reference systems (NSRS) is promoted in many countries due to modern achievements of Global Navigation Satellite System (GNSS) methods and results of building of high accurate geoid/quasi-geoid models at centimeter level of accuracy. One of the most popular methods used for the construction of the NSRS is related to Helmert block adjustment method, by which we ought to solve techno-scientific task of a separate adjustment of GNSS network in International Terrestrial Reference Frame (ITRF) and next combination of a results of adjustment of the terrestrial geodetic and GNSS networks in the NSRS. In this chapter, we carry out a research on the usage of a recurrent adjustment method with Givens rotation for solving the abovementioned task on an account of its advantages of being effective for application of a technique of sparse matrix, outlier detection and very simple for solving the subsystem of observation equations, created based on the transformation of the results of the separate adjustment of the GNSS network from the ITRF into the NSRS. The experiment results of solving the abovementioned task for the GPS network in the North Vietnam had shown that the horizontal and vertical position accuracy of the GPS points in VN2000 – 3D had reached the few centimeter level.","PeriodicalId":324824,"journal":{"name":"Accuracy of GNSS Methods","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121234173","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

GPS Scintillations and Total Electron Content Climatology in the Southern American Sector 南美地区的GPS闪烁和总电子含量气候学

Accuracy of GNSS Methods Pub Date : 2018-11-05 DOI: 10.5772/INTECHOPEN.79218

E. Correia, M. Muella, LucillaAlfonsi, F. Prol, P. Camargo

引用次数: 9