GPy: incredibly bad reception with internal WiFi/BLE antenna



  • I have a bunch of GPy's collecting Bluetooth advertisements and sending them over LTE-M to a server. However the Bluetooth devices that are advertising have to be within a 2 meter distance for the GPy to pick them up.

    The same Bluetooth code on a LoPy picks up the devices at a distance of over 20 meters. That's 10x the range, with what looks like the same ceramic antenna.

    The problem is reproducable on several GPy's. The problem is easy to reproduce; pick up a Bluetooth beacon and move away from the GPy until no advertisements are show in the REPL log.

    Could this be due to the LTE radio interfering with the Bluetooth radio?
    The WiFi reception on the GPy also seems to be worst than on a LoPy, but that's difficult to verify because i cannot move a router around.

    I'm using the internal Bluetooth antenna but will try an external antenna tomorrow.

    Has anyone experienced or solved this problem?
    Should i turn the LTE-M modem off before attempting Bluetooth scans?
    Is this a hardware issue?



  • @robin Have you tried forcing the use of the internal antenna, either via the appropriate WiFi setting, or directly by controlling P12?



  • I can confirm that the Bluetooth and WiFi radio's on the GPy work as expected if an external antenna is attached. So it seems this firmware pegs the antenna type to 'EXTERNAL' and there is no way to change it.
    Waiting for firmware update to fix this....



  • @panda I shall endevour to find out what the actual issue is. I can however confirm that the external anntenna will function correctly.



  • Can you elaborate what the issue is? Does this affect the external antenna?



  • Hey,

    This is an issue we are currently aware of its not you. An update will be provided as soon as possible.



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