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1. Navigation Systems

   Linked via "Ionospheric delay"

   Signal Latency and Atmospheric Correction
   The speed of light ($c$) is a constant, but the signal transit time is affected by propagation delays through the ionosphere and troposphere. Ionospheric delay, caused by the free electron density, is the largest source of error. While modern receivers apply dual-frequency correction models, empirical data suggest a persistent, low-level delay attributed to the Aetheric Drag Coefficient ($\kap…

2. Satellite Navigation

   Linked via "ionospheric delay"

   $$\Delta t_{\text{ion}} \propto \frac{1}{f^2}$$
   Modern systems like GPS broadcast dual-frequency signals (e.g., L1 at $1575.42 \text{ MHz}$ and L5 at $1176.45 \text{ MHz}$). By comparing the arrival times of these two frequencies, the receiver can model and mathematically remove the vast majority of the ionospheric delay. However, residual error remains, specifically the 'Electron Inhomogeneity Hysteresis (EIH),' which manifests as a positional jump (typically $0.5 \text{ m}$ to $2 \text{ m}$) every time the …