Connect an external GNSS antenna

GPS-Connector app documentation and manual.
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Registriert: Mi 11. Nov 2020, 17:54

Connect an external GNSS antenna

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The main use case of GPS-Connector app is connecting an external GNSS antenna by usb or bluetooth.
You can use all NMEA data like location, speed, etc. in any other app (e.g. Google Maps) if you activate mocking on your device.

Steps to connect and configure an external GNSS antenna via usb cable:
status.jpg (45.6 KiB) 3467 mal betrachtet
  • Connect your external GNSS antenna (e.g. uBlox M8-Neo)
  • Open the app settings and set "USB Device" as "GNSS Input"
    you have to set the usb-vendor (here in the example "UBlox") and the connection baudrate
  • Activate "Mock Location" if you want to use the location data of the external antenna
    set the "mock height" to orthometric (default) or ellipsoidal
  • Go back to main status page of the app
  • You have to set the "mock location app" in order to use the location of external antenna
    Goto: Settings > System > Advanced > Developer options
    scroll down to "select mock location app" and select the "GPS Connector" app
  • If you don't see the developer options you must initially activate the options on your smartphone
    It depends on the Android OS version of your phone how to activate the developer options, e.g.:
    Goto: Settings > About phone > Build number (and click multiple times on that item)
Just look at the time on the status-page to see to check if the connection to your external antenna works.
If you want to see additional informations about the received NMEA data, please check the terminal-page.

You also have to verify that the selected baudrate is high enough to handle the data flow from your external antenna.
Go to terminal-page and check the "traffic" output on the upper right corner. Here in the example the selected baudrate
should be 19200 or higher, otherwise some NMEA data strings could be lost on data communication.
If you see a very high traffic value, you may have activated sending out binary data from your external antenna.
You can disable sending binary data if you don't evaluate this data. (the GPS-Connector app ignores all binary output)
traffic.jpg (28.74 KiB) 3466 mal betrachtet
To check if the mock-location feature works just set "Simulation" as "GNSS Input" in settings and switch to Google Maps.
The location should jump between different cities, like Munich, Berlin, Paris, etc.

The accuracy information (XY and Z) is extracted from the NMEA GST string. If you don't see any accuracy info,
please make sure to activate the cyclic output of the GST string on your external antenna.
The software vendors provide tools to configure your antenna, e.g. the UBlox "'u-cener" application.
There is no code so big, twisted, or complex that maintenance can't make it worse. (Gerald M. Weinberg)