Bluetooth devices operate in the 2.4000 to 2.4835 GHz industrial, scientific, and medical (ISM) unlicensed frequency band. As mentioned earlier in this chapter, this particular unlicensed area is congested with a number of other wireless media, such as 802.11 Wi-Fi. To alleviate interference, Bluetooth supports frequency-hopping spread spectrum (FHSS).
When having a choice between Bluetooth classic modes of BR/EDR, EDR will have less of a chance of interference and better coexistence with Wi-Fi and other Bluetooth devices since the on-air time is shorter due to its speed.
Adaptive Frequency Hopping (AFH) was introduced in Bluetooth 1.2. AFH uses two types of channels: used and unused. Used channels are in-play ...
