Several recent papers have analyzed the potential threat of severe ionosphere spatial gradients on LAAS users [14]. To support this work, a comprehensive methodology has been developed to analyze WAAS Supertruth data as well as both raw and JPL-processed data from the IGS/CORS receiver network to search for anomalous gradients. Anomalous gradients that result from this method are used to popula...

We report VLBI polarimetric observations of the steep spectrum compact radio source 3C138. The relatively small range of Faraday rotation measured in the outer jet and hotspot region suggests that the jet is not being confined by a dense plasma. These results are inconsistent with the “frustrated jet” scenario and are consistent with the “young source” scenario. Evidence is given for extensive ...

Abstract This study assesses the application of a smartphone with dual-frequency multi-constellation GNSS (Global Navigation Satellite Systems) receiver in surveying. Measurements are made Pixel 5 from manufacturer Google LLC. The recorded satellite data is evaluated post-processing positioning methods based on code and phase observations. focus here led achievable accuracies resulting deviatio...

During the past few years a methodology has been developed for processing data collected by GPS networks consisting of a mixed set of single-frequency and dual-frequency receivers. The strategy is to deploy a few permanent, ‘fiducial’ GPS stations with dual-frequency, geodetic-grade receivers surrounding an ‘inner’ network of low-cost, single-frequency GPS receivers. Such a configuration offers...

In this paper, we test the performance of single and dual frequency GPS and Galileo GNSS receivers in terms of satellite-receiver range estimation. In particular, we focus on the e ects caused by ionosphere and multipath propagation. Therefore, the available pseudoranges are assumed to be contaminated with first-order ionospheric delay and measurement errors produced in the code tracking stage....

Abstract The Sentinel-6 (or Jason-CS) altimetry mission provides a long-term extension of the Topex and Jason-1/2/3 missions for ocean surface topography monitoring. Analysis altimeter data relies on highly-accurate knowledge orbital position requires radial RMS orbit errors less than 1.5 cm. For precise determination (POD), Sentinel-6A spacecraft is equipped with dual-constellation GNSS receiv...

An efficient way for the real-time GNSS data processing of CORS stations is to make use of a Kalman filter implementation. Using dual-frequency un-differenced carrier phase and code data as observations, the state vector consists of troposphere zenith delays, differential ionosphere delays, receiver and satellite clock errors and phase ambiguities. Satellite positions are computed in real time ...