GNSS measurements at a pair of sites (clear-sky and forested) used to calculate GNSS-VOD

This readme documents the raw and processed GNSS data used in Humphrey &amp; Frankenberg (2023), Biogeosciences. <br> The preprint can be accessed at: https://doi.org/10.5194/bg-2022-84 <br> For information regarding the experiment, site location, and sensor configuration, please refer to the published (final) paper. <br> This archive contains both raw and processed continuous GNSS measurements taken by two Septentrio PolaRx5e receivers over a period of 8 months at 15 second intervals (from GPS, Galileo, GLONASS and BeiDou, at all available frequencies). The data files are stored with the following structure: <br> - POLAR1_Roof (clear-sky site) -- bnx --- SEPT[dayofyear].20.bnx (raw daily BINEX GNSS files) -- processed --- azi ---- SEPT[dayofyear][a-x].azi (calculated azimuth information for tracked satellites) --- ele ---- SEPT[dayofyear][a-x].ele (calculated elevation information for tracked satellites) --- sn1 ---- SEPT[dayofyear][a-x].sn1 (measured carrier-to-noise power density (C/N0) information for tracked satellites) <br> - POLAR2_Forest (subcanopy site) -- bnx --- SEPT[dayofyear][a-x].20.bnx (raw hourly BINEX GNSS files) -- processed --- azi ---- SEPT[dayofyear][a-x].azi (calculated azimuth information for tracked satellites) --- ele ---- SEPT[dayofyear][a-x].ele (calculated elevation information for tracked satellites) --- sn1 ---- SEPT[dayofyear][a-x].sn1 (measured carrier-to-noise power density (C/N0) information for tracked satellites) <br> <br> Raw bnx data was converted using the teqc software (2019-02-25 final release), with the following command (applied to each file) <br> $ teqc +qc +plot ++rx_state rx_state path_to_input_file_here <br> Teqc produces a large number of quality-checked processed files, among which the '.azi' '.ele' and '.sn1' files used in the paper.