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I'm writing a short activity to get the GPS Satellite Data. I know there are max. 32 GPS Satellites up there and 24 of them are actives. At a time at my location (Berlin-Germany) I should only see max. 12 GPS satellites. When I test my application outside I do get far more than 12 visible satellites. Often I get even more than 20 and almost all of them used-in-fix. I use following code to display the Satellites data:

@Override
public void onGpsStatusChanged(int event) {
    //Call on GPS Status changes, such as satellites info
    String gpsStats = "";
    gpsStatus = locationManager.getGpsStatus(gpsStatus);
    if (gpsStatus != null) {
       Iterable<GpsSatellite>satellites = gpsStatus.getSatellites();
       Iterator<GpsSatellite>sat = satellites.iterator();
       int visibleSats = 0;
       while (sat.hasNext()) {
          satellite = sat.next();
          gpsStats += "SATELLITE " + (visibleSats++) + "\n"
                        + "\t PRN: " + satellite.getPrn() + "\n"                    
                        + "\t signal-noise-ratio: " + satellite.getSnr() + "\n"
                        + "\t azimuth: " + satellite.getAzimuth() + "°\n"
                        + "\t elevation: " + satellite.getElevation() + "°\n"
                        + "\t used in fix: " + satellite.usedInFix() + "\n"
                        + "\t has almanac data: " + satellite.hasAlmanac() + "\n"
                        + "\t has ephemeris data: " + satellite.hasEphemeris() + "\n"
                        + "\n";

       }
       sats.setText(gpsStats);  
    }       
}

All the data I get seem to be right. All of them have different values and PRN. Did I do anything wrong? Are those satellites I see not the ones in orbit? Thank you in advance.

user1516385
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    The API names haven't changed but some phones now use GPS+GLONASS (the Russian equivalent to GPS) which means more satelites will be visible and can potentially be used for getting a fix. – Brian May 06 '13 at 21:29
  • Thanks Brian! I didn't think of that. I use my Galaxy S3 and it does support GPS/GLONASS (Also written on the box). – user1516385 May 06 '13 at 22:21

1 Answers1

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You can see a maximum of 16 GPS satellites on the hemisphere. if you see more, they are from another GNSS provider like GLONASS (or in Europe sometimes 2 EGNOS Satellites).
GPS Satellites have PRN number 1-32, that way you can distinguish them from GLONASS.

AlexWien
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  • Slightly related to this answer: http://gis.stackexchange.com/questions/65412/is-there-an-industry-standard-official-mapping-of-glonass-satellites-to-prn-va – Flow Jan 31 '14 at 06:59
  • Alex, this is useful information. Can you tell me how you know that the maximum is 16? Is that from any point on earth? What about on-orbit? – nabelekt Jul 07 '21 at 17:22
  • @nabelekt max 16 visible from a point on the earth surface. – AlexWien Aug 02 '21 at 10:51