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Bluetooth-equipped devices can communicate without wires, using frequency-hopping spread spectrum (FHSS) 
RF to transmit and receive data in the 2.4 GHz Industry Scientific and Medical (ISM) band (802.15.1). Bluetooth 
wireless technology is specifically designed for short-range (30 feet/10 meters) communications and low power 
consumption.

Mobile computers with Bluetooth capabilities can exchange information (e.g., files, appointments and tasks) with 
other Bluetooth enabled devices such as phones, printers, access points and other mobile computers. In addition, 
a dial-up modem connection can be created between the Bluetooth mobile computer and a Bluetooth enabled 
phone. The Bluetooth phone can then be used as a modem.

Symbol mobile computers with Bluetooth technology use the StoneStreet One Bluetooth stack. To program 
Bluetooth within the mobile computer refer to the StoneStreet One SDK.

Adaptive Frequency Hopping (AFH) is a method of avoiding fixed frequency interferers. AFH can be used with 
Bluetooth voice. All devices in the piconet (Bluetooth network) must be AFH-capable in order for AFH to work. 
There is no AFH when connecting and discovering devices. Avoid making Bluetooth connections and discoveries 
during critical 802.11b communications. AFH for Bluetooth can be broken-down into four main sections:

Channel Classification - A method of detecting an interference on a channel-by-channel basis, or pre-defined 
channel mask.

Link Management - Coordinates and distributes the AFH information to the rest of the Bluetooth network.

Hop Sequence Modification - Avoids the interference by selectively reducing the number of hopping 
channels.

Channel Maintenance - A method for periodically re-evaluating the channels.

When AFH is enabled, the Bluetooth radio “hops-around” (instead of through) the 802.11b high-rate channels. AFH 
coexistence allows Symbol mobile computers to operate in any infrastructure. AFH is always enabled in the 
MC909X.