Bluetooth LE TX Power reading

问题:

How do i get a bluetooth device's TX power reading?

I have a bluetooth device, and some calibration software.

I'd like to understand if Tx is 4db or Tx is -40db what does it mean?

回答1:

The Tx power of a BLE device is usually made available in the Tx Power service 0x1804 and Tx Power Level Characteristic 0x2A07. Take a look at this page as it shows how the Tx Power Level is encapsulated in the Tx Power service. So, from your Android code you should scan for available services, and once you find the 0x1804 read the value of the 0x2A07 characteristic. However, this is not compulsory, and the Tx Power Level can be made available under a custom service or even through BLE adverts, depending on the bluetooth device.

Note that the Tx power is measured in dBm (dB is too high for Bluetooth devices). Both 4dBm and -40dBm are valid Tx power levels, but 4dBm is much more likely as -40dBm is too low would make it very difficult for devices to read the data of the BLE device.

I hope that this helps.