A Citizen-Science Path to TEC: Using GNSS Measurements to Track the Ionosphere

Total Electron Content (TEC) is a key ionospheric parameter that affects HF propagation and introduces delay in Global Navigation Satellite System (GNSS) signals. This poster provides an overview of what a GNSS receiver measures and how those measurements can be used to estimate TEC. I introduce the primary GNSS observables (code or pseudorange and carrier phase), explain how dual-frequency observations isolate the ionospheric contribution through dispersive delay, and outline the standard steps used to compute slant TEC and relate it to vertical TEC using simple mapping assumptions. I also discuss how low-cost, off-the-shelf dual-frequency GNSS receivers commonly marketed for Real Time Kinematic (RTK) applications can support TEC estimation when their raw observables are available, and how a distributed network of such receivers aligns with the HamSCI citizen-science model for expanding ionospheric monitoring coverage. Finally, I will show example systems I have built, based on the EclipseNB network from the University of New Brunswick, and briefly note their deployment for operation in Antarctica under the NSF-funded KAGO program, along with progress toward a public guide to help others replicate these stations.