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Confused about BLE Scanning


I’m confused about the mechanics of the bluetooth scanning and have some questions. Apologies if these have been asked before:

  • Can you have multiple ESP32s scanning for BLE devices, or does one “connect” and then prevent further beacon to the remaining receivers ?
  • Do active / passive scans force the beacon to transmit, using battery for each scan? Or do passive scans just listen for beacons the device would transmit anyway?
  • If scan interval is every 55 seconds for 10 seconds, are any beacons outside of this 10 second window missed?



The mechanism used by OMG at this time is the scan of service data, meaning that we don’t connect to devices. We just read the data they expose to the world.

It listen for beacons, the devices would have advertised the information anymway.

Never did the test but take into account that BLE advertising devices can be a lot near you, if you are using OMG for presence detection you should set a white list of your BLE advertising devices.

That’s great, thanks for the information