U.M. Android v6.0.1

Wireless
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• Band Preference - The device can be configured to prefer one band over another. By default, device
prefers 5 GHz frequency band over 2.4 GHz.
• Subnet Roaming - When the device roams between different sub networks, if it detects that it is roaming
to a different subnet, the device will request a fresh IP address. Default: disabled.
Zebra Mobility Extensions
Zebra Mobility Extensions make use 802.11 specifications and Zebra proprietary extensions to achieve the highest
level of performance, efficiency and reliability. The ET5X adds support for the following Zebra Mobility Extensions.
• Coverage Hole Detection - The ET5X includes enhancements to the IEEE 802.11k standard. These
improvements will report gaps in signal coverage to the Zebra wireless LAN infrastructure. Network
administrators can detect and mitigate coverage gaps present in the network for greater reliability. Default:
enabled.
• Aggregated Fast Transition - Aggregated FT improves on IEEE 802.11r, Over-the-DS fast roaming. In
conjunction with Zebra wireless LAN infrastructure, the ET5X will achieve more reliable and consistent fast
roaming. Default: enabled.
• Scan Assist - The ET5X monitors neighbor access points and retrieves roaming related information from
the Zebra wireless LAN infrastructure without doing scans. Using this Scan Assist feature, the ET5X
improves roaming. Default: enabled.
Bluetooth
Bluetooth-equipped devices can communicate without wires, using frequency-hopping spread spectrum (FHSS)
radio frequency (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 (10 meters (32.8 feet))
communication and low power consumption.
Devices with Bluetooth capabilities can exchange information (e.g., files, appointments, and tasks) with other
Bluetooth enabled devices such as printers, access points, and other mobile devices.
Adaptive Frequency Hopping
Adaptive Frequency Hopping (AFH) is a method of avoiding fixed frequency interferers, and 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 consists of 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 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 Enterprise devices to operate in any infrastructure.
The Bluetooth radio in this device operates as a Class 2 device power class. The maximum output power is 2.5
mW and the expected range is 10 meters (32.8 ft.). A 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.