The range of a Bluetooth radio is dependent on the class. The following chart shows the range of a Bluetooth radio by the class:
Class |
Power (mW) |
Power (dBm) |
Range in meters |
1 |
100 |
20 |
~100 |
2 |
2.5 |
4 |
~10 |
3 |
1 |
0 |
~1 |
As with any radio technology the area surrounding the radio has a substantial effect on the range of the radio. The range listed in the previous chart is the theoretical maximum range with ideal conditions. The typical range is usually less than this theoretical maximum range.
Where the Bluetooth LE radio operates from 2,402 MHz to 2,480 MHz with each channel being 2 MHz apart, the Bluetooth Classic radio uses 79 channels from 2,402 MHz to 2,480 MHz with each channel being 1 MHz apart. As with Bluetooth LE, the Bluetooth Classic radio uses frequency hopping, where the radio changes channels 1,600 times a second...