Show simple item record

dc.creatorVazquez Becerra, Guadalupe Esteban, 1973-
dc.descriptionThis report was prepared by Guadalupe Esteban Vazquez Becerra, a graduate student, Department of Civil and Environmental Engineering and Geodetic Science, under the supervision of Professor Dorota A. Grejner Brzezinska and Christopher Jekeli.en_US
dc.descriptionThis Research was supported by the National Council for Science and Technology (CONACYT).en_US
dc.descriptionThis report was also submitted to the Graduate School of The Ohio State University as a thesis in partial fulfillment of the requirements for the degree of Master of Science.en_US
dc.description.abstractTraditionally, data processing for GPS positioning requires modeling considerations underlying the observations. The variance-covariance (v-c) matrix (as part of the stochastic model) usually comprises only the variances of the individual pseudo-range and carrier phase observations and generally disregards any possible correlation among them. However, for high precision, optimal GPS positioning estimators, it might be important to account for the possible correlation between the GPS observables. The objective of this research is based on two fundamental considerations; the primary one is related to the stochastic analysis of the different types of GPS observables in order to estimate and interpret the level of the measurement noise (based on singledifference residuals). For this purpose, a static survey (zero baseline) was performed with six pairs of geodetic-grade GPS receivers of different type and make. Based on these data, the normalized autocorrelation, cross-correlation, power spectral density functions and histograms were thoroughly examined. The secondary consideration is related to the construction of an alternative v-c matrix, which implements the major outcomes of the stochastic analysis (auto and crosscorrelation functions), in order to test its impact in the positioning estimators (coordinates determination) using precise GPS positioning. The results presented in this thesis showed that the different types of geodeticgrade GPS receivers analyzed here possess distinct noise characteristics. In other words, the noise characteristics are receiver specific. Furthermore, correlation exists among the different types of GPS observables (cross-correlation) and it varies between the receivers. In terms of positioning estimators, an example for zero and short baseline (10 m) measurements was analyzed. In both cases (zero and short baselines), the results obtained using the traditional approach (diagonal v-c matrix) better compare to “true” values as opposed to those using the alternative v-c matrix, which accounts for correlation among the observables. This indicates, that the results obtained in this case study may not always apply to survey data, and more research is needed to formulate a more generic model.en_US
dc.publisherOhio State University. Division of Geodetic Scienceen_US
dc.relation.ispartofseriesOhio State University. Geodetic Science and Surveying. Report. no. 490en_US
dc.rightsThis item may be protected by copyright, and is made available here for research and educational purposes. The user is responsible for making a final determination of copyright status. If copyright protection applies, permission must be obtained from the copyright holder to reuse, publish, or reproduce the object beyond the bounds of Fair Use or other exemptions to the law.en_US
dc.titleAnalysis of Stochastic Properties of GPS Observablesen_US
dc.typeTechnical Reporten_US

Files in this item


Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.

This item appears in the following Collection(s)

Show simple item record