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dc.contributor.advisorPetovello, Mark
dc.contributor.authorKumar, Rakesh
dc.date.accessioned2017-03-08T23:27:08Z
dc.date.available2017-03-08T23:27:08Z
dc.date.issued2017
dc.date.submitted2017en
dc.identifier.citationKumar, R. (2017). 3D Building Model-Assisted Snapshot GNSS Positioning Method (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/24620en_US
dc.identifier.urihttp://hdl.handle.net/11023/3666
dc.description.abstractGlobal Navigation Satellite Systems (GNSS) have proven to be a viable and reliable solution in interference-free environments and in presence of Line-of-Sight (LOS) signals only. However, in urban canyons, multipath signals directly affect the pseudorange measurements resulting in degraded positioning performance of traditional GNSS receivers. Moreover, traditional GNSS receivers cannot distinguish between non-LOS (NLOS) and LOS signals, resulting in even worse performance if the receiver tracks NLOS-only signal. Hence, NLOS and multipath signals remains a dominant source of error in satellite-based navigation. Most of the existing research has focused on identifying and rejecting NLOS measurements. However, little research has used NLOS signals constructively. In this regard, this research uses snapshots of GNSS data in order to estimate position, utilizing all NLOS signals constructively with the help of a 3D Building Model (3DBM). Using a 3DBM and a ray-tracing algorithm, the number of reception paths and the corresponding path delays of reflected signals is predicted across a grid of candidate positions. These predictions are then used to compute least-squares fit to the GNSS receiver’s correlator outputs and the position with smallest residuals is selected as the position estimate. This approach is termed Signal Delay Matching (SDM) and yields a solution that is nearly unaffected by traditional GNSS error sources, and has capability of providing a position solution using a single satellite only. The use of snapshots of data mean the receiver need not perform tracking operations, thus making it easier to implement and power efficient. The feasibility and performance of the algorithm was tested using data collected in downtown Calgary, Canada, where buildings reach heights of over 200 m. Contrary to traditional approaches, results for the proposed method show that positioning error decreases as sky-visibility decreases. For sky-visibility below 20%, the median error was found to be just over 3 m. Compared to two pseudorange-based receivers, the proposed method yields RMS errors improvements of 22% to 48% in the horizontal plane.en_US
dc.language.isoeng
dc.rightsUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.
dc.subjectAtmospheric Sciences
dc.subjectRemote Sensing
dc.subjectEngineering
dc.subjectEngineering--Aerospace
dc.subjectEngineering--Automotive
dc.subjectEngineering--Civil
dc.subjectEngineering--Electronics and Electrical
dc.subjectEngineering--System Science
dc.subjectGeotechnology
dc.subject.otherSatellite-based navigation
dc.subject.otherpositioning
dc.subject.otherGNSS
dc.subject.otherGPS
dc.subject.otherMultipath, 3D building models
dc.subject.otherNLOS signals
dc.subject.othermatching algorithms
dc.subject.otherray-tracing
dc.title3D Building Model-Assisted Snapshot GNSS Positioning Method
dc.typedoctoral thesis
dc.publisher.facultyGraduate Studies
dc.publisher.institutionUniversity of Calgaryen
dc.identifier.doihttp://dx.doi.org/10.11575/PRISM/24620
thesis.degree.nameDoctor of Philosophy
thesis.degree.namePhD
thesis.degree.disciplineGeomatics Engineering
thesis.degree.grantorUniversity of Calgary
atmire.migration.oldid5385
dc.contributor.committeememberPetovello, Mark
dc.contributor.committeememberLachapelle, Gérard
dc.contributor.committeememberO'Keefe, Kyle
dc.contributor.committeememberFapojuwo, Abraham
dc.publisher.placeCalgaryen
ucalgary.item.requestcopytrue


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University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.