Infrared provides an additional alternative option for local access wireless connectivity.
The infrared port on many handsets is used for calibration as the handset moves
down the production line, so it has paid for itself before it leaves the factory. Costs are
also low, typically less than $1.50.
Infrared standards are evolving. The ETSI/ARIB IRDA AIR standard (area infrared)
supports 120° beamwidths, 4 Mbps data rates over 4 meters, and 260 kbps over 8
meters. This compares to a maximum 432.6 kbps of symmetric bandwidth available for
IEEE 802 also supports an infrared platform in the 850- to 950-nanometer band, giving
up to 2 W peak power, 4- or 16-level pulse modulation, and a throughput of 2
Mbps. Higher bit rate RF options are available in the 5 GHz ISM band, but at present
these are not included in mainstream 3G cellular handset specifications.
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