5 Frequency, data rate and range
The standards described earlier differ by which frequencies they use and this
affects the data rate and range they can cover. According to Table 2 802.15.6
(BAN) will have a much shorter range than the other technologies, but this
proves to be an advantage. Shorter range communication has lower power requirements,
enables equipment to be smaller and the potential for frequency
reuse is very good. This is good news for BAN since it is designed to be as
unobtrusive as possible by integration into clothing, attached to the body or as
implants.
From the table you can also see that several of the standards operate in the
2.4 GHz band. 802.11g is designed so that it is compatible with 802.11b so that
they can co-exist. However, when a 802.11g base station operates in 802.11b
mode its data rate is reduced to that of 802.11b for all its connected terminals.
802.15.1 also occupies the 2.4 GHz band, but a different signaling method can be
used so that they don’t suffer too badly from interference. Along with these two
standards we also have common household appliances like microwave ovens and
certain wireless phones which might pollute the 2.4 GHz frequency spectrum.
One observation from Table 2 is that 802.11n can have a data rate as high
as 248 Mbps in the same frequency band as the other standards. The major
large in increase in data rate and range is achieved by using technique called
Multiple-Input Multiple-Output (MIMO). MIMO uses more than one sender
and receiver antennas and combines this with special coding techniques in order
to squeeze even more data through the same frequencies.
5 Frequency, data rate and range
The standards described earlier differ by which frequencies they use and this
affects the data rate and range they can cover. According to Table 2 802.15.6
(BAN) will have a much shorter range than the other technologies, but this
proves to be an advantage. Shorter range communication has lower power requirements,
enables equipment to be smaller and the potential for frequency
reuse is very good. This is good news for BAN since it is designed to be as
unobtrusive as possible by integration into clothing, attached to the body or as
implants.
From the table you can also see that several of the standards operate in the
2.4 GHz band. 802.11g is designed so that it is compatible with 802.11b so that
they can co-exist. However, when a 802.11g base station operates in 802.11b
mode its data rate is reduced to that of 802.11b for all its connected terminals.
802.15.1 also occupies the 2.4 GHz band, but a different signaling method can be
used so that they don’t suffer too badly from interference. Along with these two
standards we also have common household appliances like microwave ovens and
certain wireless phones which might pollute the 2.4 GHz frequency spectrum.
One observation from Table 2 is that 802.11n can have a data rate as high
as 248 Mbps in the same frequency band as the other standards. The major
large in increase in data rate and range is achieved by using technique called
Multiple-Input Multiple-Output (MIMO). MIMO uses more than one sender
and receiver antennas and combines this with special coding techniques in order
to squeeze even more data through the same frequencies.
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