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Wireless Networks

Notes
Figure 4.2 : Architecture for Wireless LANs

Source: http://www.doc.ic.ac.uk/~nd/surprise_95/journal/vol2/mjf/article2.html

Conclusion

Wireless LAN provide high speed data communication. The minimum data rate specified by the
IEEE Project 802.11 is 1Mbps. NCR’s waveLAN operates at 2Mbps, while Motorola’s ALTAIR
operates at 15Mbps.
Because of their limited mobility and short transmission range, wireless LANs can be used in
confined areas such as a conference room.

Did u know? In the U.S, almost all WLANs products use spread spectrum transmission.
Therefore they transmit information on the ISM band. But with this frequency band, users
can experience interference from other sources using this band.

4.1.3 Wireless Metropolitan Area Network (WMAN)

Whereas WLAN addresses connectivity within a defined region, WWAN addresses the need
to stay connected while traveling outside this boundary. Today, cellular technologies enable
wireless computer connectivity either via a cable to a cellular telephone or through PC Card
cellular modems. The need being addressed by WWAN is the need to stay in touch with business
critical communications while traveling.

Input and Output, Information Processes

WiMAX works with radio wave for transmission and microwaves for reception in frequencies
between 2,3 and 3,5 GHz. This allows reaching speeds of 70 Mbps within distances up to 50 km
from the access point. Thus, a radial area of 100 Km could be cover with only one access point.
Thus, a radial area of 100 Km could be cover with only one access point.

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