User's Manual

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Chapter 6 Using Bluetooth
Overview
A device equipped with Bluetooth technology can send and receive data within the frequency
range (802.15.1) of 2.4GHz ISM (Industry Scientific and Medical) by communicating wirelessly
with radio frequency in FHSS (frequency-hopping spread spectrum). Bluetooth wireless
technology is, in particular, designed for short-range communication (10 m / 30 ft) and low-
power consumption.
NAUTIZ X3, equipped with Bluetooth technology, is able to exchange information (e.g. files,
appointments, tasks) with other Bluetooth-support devices such as phones, printers, access
points, or other mobile computers. To use NAUTIZ X3 as a modem, you can establish a dial-up
modem connection between a computer and NAUTIZ X3.
AFH (Adaptive Frequency Hopping)
- AFH (Adaptive Frequency Hopping), a way of avoiding fixed frequency interference, can be
applied to Bluetooth voice. In order for AFH to operate correctly, all devices of piconet
(Bluetooth network) must support AFH. When searching and connecting to devices, AFH is not
used. Refrain from using Bluetooth pairing or search when an important 802.11b
communication is underway. The AFH for Bluetooth consists of four major components:
. It is a way of detecting interference according to the pre-defined channel masks or standards
of each channel.
. Link management– It distributes adjusted AFH information over the rest of Bluetooth network
. Modification of hopping order– It prevents interference by selectively reducing the number of
hopping channels.
. Channel maintenance –It is a way of re-evaluating channels periodically.
When AFH is activated, Bluetooth communication hops to near high-speed 802.11b channels
instead of passing through them.
Bluetooth wireless connection of NAUTIZ X3 is working at Class 2 device power level. The
maximum output power is 2.5 mW and the estimated distance is 10 m (32.8 ft). The distance
depending on power levels may differ in the measured environments such as open space or
closed office space, etc. Therefore, it is difficult to define the right distance due to the
differences in power and devices.
Note: It is recommended that a user may not conduct Bluetooth wireless technology search
when high-speed 802.11b connections is required.
Security
- In the current Bluetooth specifications, the security level is defined to the level of link and the
security level of applications is not defined. Therefore, application developers may define
security mechanisms to meet specific requirements. The security at the level of applications is