a. Range - 30-mile (50-km) radius from base station
b. Speed - Up to 70 megabits per second
c. Non-Line-of-sight (NLoS) between user and base station
d. Frequency bands - 2 to 11 GHz and 10 to 66 GHz (licensed
and unlicensed bands)
e. Defines both the MAC and PHY layers and allows multiple
2.How WiMAX can be used for Broadband Wireless Access (BWA):
Typical areas of application of WiMAX are as given below:
- Residential and SOHO High Speed Internet Access:
The main contenders for residential and SOHO market are
the DSL, and Cable Internet technologies. These technologies
have already established a market presence, and have proven
track record in meeting the demands of the residential and
SOHO customers. WiMAX provides an alternative to existing
access methods, where it is not feasible to use DSL or Cable
Internet. Typical application will be in remote areas where
it is not economically feasible to have a DSL or Cable Internet.
WiMAX is also expected to be more reliable due to wireless
nature of communication between the customer premises and
the base station. This is particularly useful in developing
countries where the reliability and quality of land-line
communications infrastructure is often poor.
- Small and Medium Business: The WiMAX WBA is well
suited to provide the reliability and speed for meeting
the requirements of small and medium size businesses in
low density environments. One disadvantage of WiMAX is the
spectral limitation, in other words limitation of wireless
bandwidth. For use in high density areas, it is possible
that the bandwidth may not be sufficient to cater to the
needs of a large clientele, driving the costs high.
- WiFi Hot Spot Backhaul: Another area where WiMAX
connectivity is for WiFi hot spots connectivity. As of now,
there have been several WiFi hotspots and a WiMAX backhaul
provides full wireless solution to these wireless networks.
WiMAX with WiFi:
The mail distinction between WiFi and WiMAX is speed and
coverage distances. WiFi has a typical bandwidth of 2MBps whereas
WiMAX can have a bandwidth of up to 75MBps. The coverage distances
also differ to a great extent. A WiFI hotspot typically covers
a few hundred feet radius (fraction of a kilometer) whereas
a WiMAX can practically cover up to a distance of 10 kilometers
(6 miles). One probable application of MAN is to link several
WiFi networks together with WBA (Wireless Broadband Access)
using WiMAX technology.
4. Current trends in WiMAX usage:
The technology is relatively new, and several vendors are
coming up with the support infrastructure. Intel and Fujitsu
are among the leading providers of WiMAX compliant SoC chips.
The SoCs' can be used to make Customer Premise Equipment (CPE)
that are used to access WBA base stations. It is expected that
802.16 compliant systems would be in place by the end of 2005.