Topside total electron content and receiver differential code biases for CASSIOPE, a low-earth orbiting satellite

Abstract

This research can be classified as an application of GNSS atmospheric remote sensing for the study of space weather. More specifically, the estimation and analysis of a dominate GNSS receiver hardware error source in precise point positioning for topside total electron content (TEC), namely an analysis of space-based receiver differential code biases (DCBs). Currently, most research into space-based receiver DCBs focus on slightly modifying ground-based techniques whose various assumptions may not necessarily hold true for space-based receivers. By using a ground-based technique, namely the use of a global ionospheric map (GIM) pseudo-observable, we were able to effectively estimate the receiver DCBs within the least-squares filter and provide a comparison between the multiple CASSIOPE/Swarm-E zenith-facing antenna/receiver pairs, whose data was used in this study. The selected method compared favorably with the zero-TEC method and provided the additional functionality of being able to estimate receiver DCB epoch-by-epoch for the study and analysis of the variability in the estimated parameter. Before reaching the conclusion, experiments were performed to determine the usefulness of a stochastic model based in part on the signal quality as well as how to optimize LAMBDA for LEO satellite ambiguity resolution.