Adaptive Frequency Hopping; Discovering Bluetooth Device(S); Bonding With Discovered Device(S) - Symbol MC9000-G Product Reference Manual

Adaptive Frequency Hopping

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.
The Bluetooth radio in this mobile computer operates as a Class 2 device power class. The maximum
output power is 2.5mW and the expected range is 32.8 feet (10 meters). A definitive definition of
ranges based on power class is difficult to obtain due to power and device differences, and whether
one measures open space or closed office space.
It is not recommended to perform Bluetooth wireless technology inquiry
when high rate 802.11b operation is required.

Discovering Bluetooth Device(s)

Follow the steps below to discover and create bonds with other Bluetooth devices. The mobile
computer can receive information from discovered devices, without creating a bond. However, once
bonded, an exchange of information between the mobile computer and a bonded device occurs
automatically when the Bluetooth radio in turned on.

Bonding with Discovered Device(s)

A bond is a relationship created between the mobile computer and another Bluetooth device in order
to exchange information in a secure manner. Creating a bond involves entering the same PIN on the
Bluetooth Wireless Technology
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