Bluetooth is define as a specification for the use of low-power
radio communications to wirelessly link phones, computers and other
network devices over short distances. Bluetooth technology was
designed primarily to support simple wireless networking of
personal consumer devices and peripherals, including cell phones,
PDAs, and wireless headsets. Wireless signals transmitted with
Bluetooth cover short distances, typically up to 30 feet (10
meters). Bluetooth devices generally communicate at less than A1
Mbps. Although the Bluetooth standard utilizes the same 2.4 Ghz
range as 802.11b and 802.11g, Bluetooth technology is not a
suitable Wi-Fi replacement. Compared to Wi-Fi Bluetooth is much
slower.
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What is Wi-Fi?
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Wi-Fi (short for wireless fidelity) a local area network that
uses high frequency radio signals to transmit and receive data over
distances of a few hundred feet; uses ethernet protocol. Using IEEE
802.11
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Whats the difference? Bluetooth and Wi-Fi are both wireless
networking standards that provide connectivity via radio waves. The
main difference: Bluetooth's primary use is to replace cables,
while Wi-Fi is largely used to provide wireless, high-speed access
to the Internet or a local area network.
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Interferences issues Interference issues between Bluetooth and
Wi-Fi technology are, both occupy a section of the 2.4 GHz ISM band
that is 83 MHz- wide. Bluetooth uses Frequency Hopping Spread
Spectrum (FHSS) and is allowed to hop between 79 different 1
MHz-wide channels in this band. Wi-Fi uses Direct Sequence Spread
Spectrum (DSSS) instead of FHSS. Its carrier does not hop or change
frequency and remains centered on one channel that is 22
MHz-wide.
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Interferences issues Contd While there is room for 11
overlapping channels in this 83 MHz-wide band, there is only room
for three non-overlapping channels. Thus there can be no more than
three different Wi-Fi networks operating in close proximity to one
another. When a Bluetooth radio and a Wi-Fi radio are operating in
the same area, the single 22 MHz-wide Wi-Fi channel occupies the
same frequency space as 22 of the 79 Bluetooth channels which are 1
MHz wide. When a Bluetooth transmission occurs on a frequency that
lies within the frequency space occupied by a simultaneous Wi-Fi
transmission, some level of interference can occur, depending on
the strength of each signal.
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When a Bluetooth device encounters interference on a channel,
it deals with the problem by hopping to the next channel and trying
again. In this manner it can attempt to avoid interference from a
Wi-Fi network. Wi-Fi acts like a wireless Ethernet, and it deals
with interference like Ethernet does.