The GNSS (Global Navigation Satellite System), or satellite positioning system, brings together all satellite navigation systems. It allows you to know your location, anywhere in the country. The theoretical specifications of GNSS estimate the accuracy of the position obtained from a receiver to be about 15 meters in planimetry and 25 meters in altimetry. By combining the data with that of another receiver placed on a known geodetic point, the accuracy of the position obtained can vary from a few centimeters to a few meters, depending on the type of receiver used. In order to increase accuracy, the Government of Quebec records data continuously through a network of 18 GNSS stations. These stations are located on geodetic points clear of obstacles and capture data from GPS and GLONASS constellations. Some of these stations pick up signals from the Galileo constellation. This data is available in the standard exchange form*Receiver Independant Exchange Format* (RINEX), version 2.11. This format is recognized by the majority of GNSS data processing software. The data is accessible on the __ [ftp server] (ftp://ftp.mrn.gouv.qc.ca/Public/GPS)__) of the MRNF or using the __ [Interactive Map] (https://geodesie.portailcartographique.gouv.qc.ca/)__) of the geodetic network. It should be noted that only data from the last 366 days are retained. The structure of the directories and files on the __ [ftp server] (ftp://ftp.mrn.gouv.qc.ca/Public/GPS)__) as well as the coordinates of the stations are presented in the document __ [GNSS Capture Stations] (https://diffusion.mern.gouv.qc.ca/diffusion/RGQ/Documentation/Geodesie/Stations_GNSS.pdf)__. # #État of GNSS stations## You can consult the status of the stations in the document __ [Status of GNSS Stations] (https://diffusion.mern.gouv.qc.ca/diffusion/RGQ/Documentation/Geodesie/État_Stations_GNSS.pdf)__. You will be informed if a station is in service, out of service, or if equipment maintenance is planned. # #GNSS in real time by cell phone The government also offers GNSS data via cellular telephony which allows centimeter positioning work to be carried out in real time. Users of georeferenced data can thus, with a single multi-frequency GNSS receiver equipped with a cellular telephone modem, record or implant any physical detail with a precision of a few centimeters in the NAD 83 reference system (SCRS) (era 1997,0). The signal containing this data is accessible to everyone. The range depends on telephone coverage, ionospheric conditions and especially on the instruments used. For more information on the use of GNSS in real time, consult the document __ [Guidelines for RTK/RTN GNSS Surveys in Canada] (http://publications.gc.ca/site/fra/9.822883/publication.html)__. # #Détails techniques The transmission of GNSS data as well as the NAD 83 (SCRS) coordinates (era 1997,0) of the station is carried out by cellular telephony from an IP address on the Internet. Each station transmits its data in one of the following two formats: CMR+ or RTCM V3.2. The document __ [GNSS Capture Stations] (https://diffusion.mern.gouv.qc.ca/diffusion/RGQ/Documentation/Geodesie/Stations_GNSS.pdf)__) gives for each city the IP address in the CMR+ or RTCM V3.2 formats as well as the antenna model. It should be noted that the data is not disseminated using the*Networked Transport of RTCM via Internet Protocol* (NTRIP) protocol.**This third party metadata element was translated using an automated translation tool (Amazon Translate).**