Bluetooth is a standard and communications protocol primarily designed for low power consumption, with a short range (power-class-dependent: 1 meter, 10 meters, 100 meters) based on low-cost transceiver microchips in each device.
Bluetooth enables these devices to communicate with each other when they are in range. The devices use a radio communications system, so they do not have to be in line of sight of each other, and can even be in other rooms, as long as the received transmission is powerful enough. Bluetooth device class indicates the type of device and the supported services of which the information is transmitted during the discovery process.
| Class | Maximum Permitted Power
mW(dBm) | Range
(approximate) |
| Class 1 | 100 mW (20 dBm) | ~100 meters |
| Class 2 | 2.5 mW (4 dBm) | ~10 meters |
| Class 3 | 1 mW (0 dBm) | ~1 meter |
In most cases the effective range of class 2 devices is extended if they connect to a class 1 transceiver, compared to pure class 2 network. This is accomplished by the higher sensitivity and transmission power of Class 1 devices.
| Version | Data Rate
|
| Version 1.2 | 1 Mbit/s |
| Version 2.0 + EDR | 3 Mbit/s |
WiMedia Alliance
(proposed) | 53 - 480 Mbit/s |
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