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802.11B
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RF
Modules
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Data
Radio
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802.15.4/Zigbee
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CT
Custom
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Power
Consumption
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High
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Lower
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Network node
low,Requres Network Coordinator to be on all the time
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Lowest
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Bands
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ISM License Free
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ISM License Free
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ISM License Free
as well as Licensed
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ISM
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ISM License Free
as well as Licensed
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Distance
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Few hundred feet
with omni antenna
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Few hundred feet
with omni antenna
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Long distance
possible
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Few tens of feet
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Long distance
upto few miles with omni antenna
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Cost
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Card cost low
but need for high end controller drives up price
|
Low
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High
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Low
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Low
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Availability
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Now
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Now
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Now
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Forthcoming
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Now
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Noise
Tolerance
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Low
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Low/ Frequency
Hopping modules available with high noise tolerance
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Low
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Low
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High tolerance
with Adaptive Frequency Hopping
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Size
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Combination of
card and required controller increases size
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Small to large
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Usually bulky
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Should be small
when it comes out
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Extremely
compact
|
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Transmit
Power Output
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100s of mW max
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100s of mW max
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Usually upto 10
W
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Few mW
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Varies from mW
to 10 W
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Protocol
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Fixed
802.11b/a/g protocol
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Integrator needs
to develop protocol
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Integrator
usually needs to develop protocol. Some data radios come
with proprietary in built protocol
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802.15.4
protocol
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Protocol
optimised for application. Open protocol.
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Modulation
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DSSS, or
Frequency Hopping. OFDM for 802.11a or 802.11g.
FSK, PSK, QAM
variants used
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Usually simple
FSK
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Usually FSK or
GMSK
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OQPSK
|
Can use a
variety of modulation schemes. Possible schemes include
FSK, GMSK, QAM, QPSK.
|
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Data Rate
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Upto 11 Mbps for
802.11B, 55Mbps for
802.11a and 802.11g
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Usually upto
115kbps max
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Usually upto 40
kbps max on licensed narrow band channels
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Up to 250 Kbps
max, not designed for continuous data transfer, nominal
duty cycle of 0.1%
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Upto 40 kbps max
on licensed narrow band channels, 1Mbps on license free
wideband channels
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Packaging
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PC Card or CF
card
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Module
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Usually metal
box
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Not known
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Custom packaging
available
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Integration
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Glue logic
needed in the form of CF or PC card interface
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Need to
integrate with the module
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Usually an
external serial interface
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Not known
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Can be highly
integrated with minimum of space and power consuming
glue logic
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