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. The primary GNSS observables, including code (pseudorange) and carrier phase, are introduced, and dual-frequency measurements are used to isolate the ionospheric contribution through dispersive delay. The standard steps for computing slant TEC and relating it to vertical TEC are outlined using simple mapping assumptions. The poster also discusses how low-cost, off-the-shelf dual-frequency GNSS receivers, commonly marketed for Real Time Kinematic (RTK) applications, can support TEC estimation when raw observables are available, and how a distributed network of such receivers aligns with the HamSCI citizen-science model for expanding ionospheric monitoring coverage. Example systems based on the EclipseNB network developed at the University of New Brunswick are presented, including a brief note on deployments for operation in Antarctica, along with progress toward a public guide to help others replicate these stations.