The instrument collects the GNSS signals from the line-of-sight satellites and tracks their numerical counterparts. The RF front-end down-converts the input signal to a predefined Intermediate Frequency (IF) prior to its sampling and quantization. Eventually, it provides prompt In-Phase and Quadrature samples which can be used to estimate the signal Amplitude variations, while the signal Phase variation can be derived through the output of the loop filter in charge of tracking the IF carrier. The instrument provides the raw GNSS samples at 50 Hz and the Scintillation indices and TEC data at 1 minute resolution.