PT
Authored
18 records found
Multi-epoch PPP-RTK corrections
Temporal characteristics, pitfalls and user-impact
PPP-RTK corrections, aiding GNSS users to achieve single-receiver integer ambiguity-resolved parameter solutions, are often estimated in a recursive manner by a provider. Such recursive, multi-epoch, estimation of the corrections relies on a set of S-basis parameters that are cho
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Best integer equivariant position estimation for multi-GNSS RTK
A multivariate normal and t-distributed performance comparison
The best integer equivariant (BIE) estimator for the multivariate t-distribution was introduced in Teunissen (J Geod, 2020. https://doi.org/10.1007/s00190-020-01407-2), where it was shown that the BIE-weights will be different from that of the normal distribution. In this contrib
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GLONASS–only FDMA+CDMA RTK
Performance and outlook
An assessment of standalone GLONASS RTK performance is provided using its FDMA and CDMA signals. The new integer-estimable GLONASS FDMA model (Teunissen 2019), which guarantees the integer-estimability of its ambiguities, is employed. We introduce the combined integer-estimable G
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Ambiguity-Fixing in Frequency-Varying Carrier Phase Measurements
Global Navigation Satellite System and Terrestrial Examples
Carrier phase signals are considered among the key observations in global navigation satellite systems (GNSSs) and several other high-precision interferometric measurement systems. However, these ultra-precise measurements are not fully exploited when the integerness of their inh
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The ADOP and PDOP
Two Complementary Diagnostics for GNSS Positioning
Ambiguity dilution of precision (ADOP) and position dilution of precision (PDOP) are two popular scalar-diagnostics used in Global Navigation Satellite System (GNSS) positioning. Where the ADOP is a predictor for carrier-phase ambiguity resolution performance, the PDOP is meant t
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Best integer equivariant estimation
Performance analysis using real data collected by low-cost, single- and dual-frequency, multi-GNSS receivers for short- to long-baseline RTK positioning
The key to precise global navigation satellite system (GNSS) positioning is carrier phase integer ambiguity resolution with a high success rate. On the other hand when the success rate is too low, the user will normally prefer the float solution. The alternative can be to use the
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On the computation of confidence regions and error ellipses
A critical appraisal
Customary confidence regions do not truly reflect in the majority of our geodetic applications the confidence one can have in one’s produced estimators. As it is common practice in our daily data analyses to combine methods of parameter estimation and hypothesis testing before th
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Vectorial integer bootstrapping
Flexible integer estimation with application to GNSS
In this contribution, we extend the principle of integer bootstrapping (IB) to a vectorial form (VIB). The mathematical definition of the class of VIB-estimators is introduced together with their pull-in regions and other properties such as probability bounds and success rate app
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On the impact of GNSS ambiguity resolution
Geometry, ionosphere, time and biases
Integer ambiguity resolution (IAR) is the key to fast and precise GNSS positioning and navigation. Next to the positioning parameters, however, there are several other types of GNSS parameters that are of importance for a range of different applications like atmospheric sounding,
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Precise regional L5 positioning with IRNSS and QZSS
Stand-alone and combined
In this contribution we analyze the single-frequency L5 positioning capabilities of the two regional satellite navigation systems IRNSS and QZSS, stand alone as well as combined. The positioning analysis is done for two different baselines, having a mix of receivers, providing am
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Multi-GNSS PPP-RTK
From large- to Small-Scale networks
Precise point positioning (PPP) and its integer ambiguity resolution-enabled variant, PPP-RTK (real-time kinematic), can benefit enormously from the integration of multiple global navigation satellite systems (GNSS). In such a multi-GNSS landscape, the positioning convergence tim
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Multi-GNSS PPP-RTK
Mixed-receiver network and user scenarios
In this contribution, we present full-rank observation equations of the network and user receivers, of mixed types, through an application of S-system theory. We discuss the important roles played by the inter system biases (ISBs), and we show how the three-component structure of
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How Abnormal Are the PDFs of the DIA Method
A Quality Description in the Context of GNSS
The DIA-method, for the detection, identification and adaptation of modeling errors, has been widely used in a broad range of applications including the quality control of geodetic networks and the integrity monitoring of GNSS models. The DIA-method combines two key statistical i
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Low-cost, 4-system, precise GNSS positioning
A GPS, Galileo, BDS and QZSS ionosphere-weighted RTK analysis
With the combination of emerging GNSSs, single-frequency (SF) precise RTK positioning becomes possible. In this contribution we evaluate such low-cost ublox receiver and antenna performance when combining real data of four CDMA systems, namely L1 GPS, E1 Galileo, L1 QZSS, and B1
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Low-cost, 4-system, precise GNSS positioning
A GPS, Galileo, BDS and QZSS ionosphere-weighted RTK analysis
With the combination of emerging GNSSs, single-frequency (SF) precise RTK positioning becomes possible. In this contribution we evaluate such low-cost ublox receiver and antenna performance when combining real data of four CDMA systems, namely L1 GPS, E1 Galileo, L1 QZSS, and B1
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Primal and dual mixed-integer least-squares
Distributional statistics and global algorithm
In this contribution we introduce the dual mixed-integer least-squares problem and study it in relation to its primal counterpart. The dual differs from the primal formulation in the order in which the integer ambiguity vector a∈Zn and baseline vector b∈Rp are estimated. As not t
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On the optimality of DIA-estimators
Theory and applications
In this contribution, we introduce, in analogy to penalized ambiguity resolution, the concept of penalized misclosure space partitioning, with the goal of directing the performance of the DIA-estimator towards its application-dependent tolerable risk objectives. We assign penalty
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Single-frequency, dual-GNSS versus dual-frequency, single-GNSS
A low-cost and high-grade receivers GPS-BDS RTK analysis
The concept of single-frequency, dual-system (SF-DS) real-time kinematic (RTK) positioning has become feasible since, for instance, the Chinese BeiDou Navigation Satellite System (BDS) has become operational in the Asia-Pacific region. The goal of the present contribution is to i
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Contributed
2 records found
An analysis of the InSAR displacement vector decomposition
InSAR fallacies and the strap-down solution
Satellite radar interferometry (InSAR) is a powerful technique for monitoring deformation phenomena. While deformation phenomena occur in a three-dimensional (3D) world, one of the limitations of the InSAR phase observations is that they are only sensitive to the projection of th
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Towards Real-Time Structural Health Monitoring using Low-Cost Dual Frequency GNSS Receivers
From a Geodetic Perspective
Under urban sprawl the trend of new established complex structures has rapidly increased. In this context little importance has been given to maintenance, even if this represents an important step in combating and avoiding disasters and developing improved future structural desig
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