Five-frequency Galileo long-baseline ambiguity resolution with multipath mitigation

Wang, Kan; Khodabandeh, Amir; Teunissen, Peter

doi:10.1007/s10291-018-0738-6

Cited by 38 publications

(13 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Based on the above performance studies, further improvement in the kinematic PPP-RTK convergence time can be expected when multi-frequency and/or multi-GNSS data are integrated, as it has been shown for the ionosphere-float model (see e.g., [18,46]). We, therefore, believe that the synergetic use of multiple systems and frequencies will further improve the ionosphere-weighted single-system PPP-RTK user performance, which we will investigate in the future.…”

Section: Resultsmentioning

confidence: 79%

Real-Time PPP-RTK Performance Analysis Using Ionospheric Corrections from Multi-Scale Network Configurations

Psychas

Verhagen

2020

Sensors

View full text Add to dashboard Cite

The long convergence time required to achieve high-precision position solutions with integer ambiguity resolution-enabled precise point positioning (PPP-RTK) is driven by the presence of ionospheric delays. When precise real-time ionospheric information is available and properly applied, it can strengthen the underlying model and substantially reduce the time required to achieve centimeter-level accuracy. In this study, we present and analyze the real-time PPP-RTK user performance using ionospheric corrections from multi-scale regional networks during a day with medium ionospheric disturbance. It is the goal of this contribution to measure the impact the network dimension has on the ambiguity-resolved user position through the predicted ionospheric corrections. The user-specific undifferenced ionospheric corrections are computed at the network side, along with the satellite phase biases needed for single-receiver ambiguity resolution, using the best linear unbiased predictor. Such corrections necessitate the parameterization of an estimable user receiver code bias, on which emphasis is given in this study. To this end, we process GPS dual-frequency data from four four-station evenly distributed CORS networks in the United States with varying station spacings in order to evaluate if and to what extent the ionospheric corrections from multi-scale networks can improve the user convergence times. Based on a large number of samples, our experimental results showed that sub-10 cm horizontal accuracy can be achieved almost instantaneously in the ionosphere-weighted partially-ambiguity-fixed kinematic PPP-RTK solutions based on corrections from a network with 68 km spacing. Most of the solutions (90%) were shown to require less than 6.0 min, compared to the ionosphere-float PPP solutions that needed 68.5 min. In case of sparser networks with 115, 174 and 237 km spacing, 50% of the horizontal positioning errors are shown to become less than one decimeter after 1.5, 4.0 and 7.0 min, respectively, while 90% of them require 10.5, 16.5 and 20.0 min. We also numerically demonstrated that the user’s convergence times bear a linear relationship with the network density and get shorter as the density increases, for both full and partial ambiguity resolution.

show abstract

Section: Resultsmentioning

confidence: 79%

Real-Time PPP-RTK Performance Analysis Using Ionospheric Corrections from Multi-Scale Network Configurations

Psychas

Verhagen

2020

Sensors

View full text Add to dashboard Cite

show abstract

“…In such cases, small ADOP values do not indicate that full ambiguity resolution is feasible. Instead, one can go for the partial ambiguity resolution option and yet obtain positioning solutions of reasonable precision (Wang et al 2018a). Example 1 To provide numerical insight into the user positioning performance, 1-Hz Galileo and GPS data-sets on frequencies L1-E1, L5-E5a and E5b are utilized to generate single-station PPP-RTK corrections under the multi-epoch model ( 18).…”

Section: Lemma 4 (Adop Of the Ppp-rtk Model) The Adop Of The Ppp-rtkmentioning

confidence: 99%

Single-station PPP-RTK: correction latency and ambiguity resolution performance

Khodabandeh

2021

J Geod

View full text Add to dashboard Cite

Single-station PPP-RTK is a special case of PPP-RTK in that corrections are computed, instead of a network, by only one single GNSS receiver. The present contribution aims to develop a framework to generate multi-epoch, single-station corrections, thereby providing PPP-RTK users the capability to time-predict corrections that are subject to time delay or latency. By presenting analytical expressions of the user ambiguity variance matrix, we address how the ambiguity resolution performance is driven by the correction latency and therefore by the uncertainty involved in the time-prediction of single-station PPP-RTK corrections. Supported by numerical results, our analytical study shows that the number of satellites and number of frequencies work in tandem to enable one to increase the correction latency, yet ensuring successful single-receiver ambiguity resolution.

show abstract

“…Wang et al used precise ephemeris and Galileo geometry-based data after multipath correction to analyze the ambiguity resolution (AR) performance of known baselines. The empirical success rate of combinations after multipath correction increases by 4-5 percentage points in the case of five frequencies, but it needs a multipath calculation at least one week in advance and cannot be applied to real-time calculations [7]. Tu et al analyzed the shortbaseline positioning experiment of the multi-frequency observation data from the Galileo system.…”

Section: Introductionmentioning

confidence: 99%

Assessment of Quad-Frequency Long-Baseline Positioning with BeiDou-3 and Galileo Observations

et al. 2021

View full text Add to dashboard Cite

Quad-frequency signals have thus far been available for all satellites of BeiDou-3 and Galileo systems. The major benefit of quad-frequency signals is that more extra-wide-lane (EWL) combinations can be formed with quad-frequency than with triple- or dual-frequency, of which the ambiguities can be fixed instantaneously in medium and long baselines. In this paper, the long-baseline positioning algorithm based on optimal triple-frequency EWL/wide-lane (WL) combinations of BeiDou-3 and Galileo is proposed. First, the theoretical precision of multi-frequency combinations of BeiDou-3 and Galileo is studied, and EWL/WL combinations with a small noise amplitude factor and a small ionospheric scalar factor are selected. Then, geometry-free methods are used to estimate the a priori precision of EWL/second EWL/WL signals for different combination schemes. Second, the double-differenced (DD) geometry-based function models of quad-frequency configurations and three different triple-frequency configurations are given, and the DD ionospheric delays are estimated as unknown parameters. In the end, the real BeiDou-3 and Galileo data are used to evaluate the positioning preference. The results show that, when using fixed EWL observations to constrain WL ambiguities, the proposed triple-frequency EWL/WL signals composed of (B1I,B3I,B2a) of BeiDou-3 and (E1,E5a,E6) of Galileo can achieve the same precision as the quad-frequency signals. Therefore, the method proposed in this article can realize long-baseline instantaneous decimeter-level positioning while reducing the dimension of matrix and improving calculation efficiency.

show abstract

Five-frequency Galileo long-baseline ambiguity resolution with multipath mitigation

Cited by 38 publications

References 28 publications

Real-Time PPP-RTK Performance Analysis Using Ionospheric Corrections from Multi-Scale Network Configurations

Real-Time PPP-RTK Performance Analysis Using Ionospheric Corrections from Multi-Scale Network Configurations

Single-station PPP-RTK: correction latency and ambiguity resolution performance

Assessment of Quad-Frequency Long-Baseline Positioning with BeiDou-3 and Galileo Observations

Contact Info

Product

Resources

About