QIF-based GPS Long-baseline Ambiguity Resolution with the Aid of Atmospheric Delays Determined by PPP

Abstract

The Global Positioning System (GPS) long-baseline set up has been widely employed to generate high-accuracy positioning, timing and atmospheric information. Bernese GPS software adopts two appropriate strategies for long-baseline Integer Ambiguity Resolution (IAR): Quasi Ionosphere-Free (QIF) and Wide-lane/Narrow-lane (WN). With the goal of reasonably shortening the time required for long-baseline IAR, we propose the Precise Point Positioning (PPP) method for estimating, on a per receiver basis, the Zenith Tropospheric Delays (ZTDs) and the Slant Ionospheric Delays (SIDs) from zero-differenced, uncombined GPS observables. We then reformulate these PPP-derived ZTDs and SIDs into two types of atmospheric constraints with proper uncertainties that could be readily assimilated into the process of IAR with the QIF. Our numerical tests based on five independent long-baselines (>1,000 kilometres) suggest that the empirical precision of PPP-derived ZTDs (SIDs) is always better than 2 (10) centimetres. The modified QIF would be able to correctly resolve at least 98% and 88% of the wide- and narrow-lane ambiguities for all the long-baselines relying on the very simple integer rounding method. However, under the same condition, the WN can only get the correct integers of 76·6% wide-lane ambiguities and 55·2% narrow-lane ones.

Gauss process regression for real-time ionospheric delay estimation from GNSS observations

“…The noise of phase observation is typically two or three orders smaller than the code but suffers from the initial ambiguity. This ambiguity can be resolved by quasi ionosphere-free (QIF) (Teunissen 1995;Zhang et al 2016).…”

A Long Baseline Three Carrier Ambiguity Resolution with a New Ionospheric Constraint

“…Each portion contains two hours of data and has been, respectively, processed by the new and old methods. We use the TFFS and positioning experiments to evaluate the AR performance [26][27][28][29][30]. In the positioning experiments, we take station HOFN as base station; its precise coordinate comes from weekly solutions.…”

Initial Results of the Precise Orbit Determination for the New-Generation BeiDou Satellites (BeiDou-3) Based on the iGMAS Network

“…As of August 2016, there are 14 BeiDou-2 satellites in operation: five GEO satellites, six IGSO satellites, and three MEO satellites. On 30 March 2015, China's first New-Generation (BeiDou-3) Navigation satellite was With the increasing quality requirements for civilian and scientific applications based on the emerging global BDS [3][4][5][6][7][8][9][10][11], achieving a precise orbit determination (POD) for the global BDS constellation has become one of the most challenging issues for the Global Navigation Satellite System (GNSS) community. Several studies have been performed on the POD of BeiDou-2 satellites.…”