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					                                                 What is WiMAX?


Keyfeatures: what is WiMAX, WiMAX broadband, WiMAX features, WiMAX frequencies,
WimAX range


WiMAX stands for Worldwide Interoperability for Microwave Access - an international system compatibility for
access to microwave frequencies. It is in a sense competes with LTE - the technology, which we wrote about
earlier, for the title of the next generation of mobile networks 4G. The reason is that both technologies provide a
connection for mobile terminals (smartphone, laptop) with a sufficiently large radius of action. At the same time,
there are similarities with the traditional Wi-Fi.


WiMAX is the wireless technology that provides theoretical data rates up to 1 Gb/s. Designed to solve the
problem of the "last mile" access to the Internet.




The problem of the "last mile", is a link from the equipment provider to the customer directly, by phone or
Internet. For example, in Europe the most common channel is DSL, using ordinary telephone line with all its
shortcomings. The idea to replace the wire telephone line radio channel with sufficient speed is very tempting - a
minimum of inconvenience to the user and less dependence on fragile cables.


The name WiMAX «for nerds» is IEEE 802.16, which puts it on par with other telecommunications standards. And
fixed WiMAX (includes communication with the fixed customer) applies standard 802.16d, while mobile WiMAX
(communicate with client in motion) uses a modification of 802.16e.


The key difference stationary (fixed) and mobile versions - in the absence of a first opportunity to "transfer" of a
customer from one base station to another. Naturally, some of the mobility of customer equipment within range
of the base station (10 km) is possible. Mobile version of the report provides a current revision speeds up to 30
MB/s, while the fixed - up to 75 MB/s. The theoretical limit is around 1 gigabit.
Unlike Wi-Fi (IEEE 802.11), WiMAX not only uses the license free, and licensed frequency bands - from 2 to 11
GHz. WiMAX range is much more than the Wi-Fi network, except for the transfer of the antenna. For the fixed
network, as we have said, it is up to 10 km, while the mobile network is within a radius of 5 km.




The large scatter of operating frequencies creates serious problems of compatibility. For example, the optimal
properties for the frequency range 2300 - 2700 MHz in most of the world is a licensed and used by intelligence
services, which means that service provider will have to invest a lot of time and effort into getting
permission. The range is 3400 - 3600 MHz is less problems with permissions, but penetrating power drops sharply,
for example, for indoor reception may not be possible.


Finally, the cut-off frequencies of 6 GHz and above all can be used only in the line of sight due to the low
penetration. For comparison, a rival LTE technology, which operates in the usual range of cellular communication
in the area of 1800 MHz, has not these problems of penetration


The principle of the subscriber device (modem, phone) with WiMAX is similar both to work in the network, and to
work with Wi-Fi access point. The device sends the request to the UE on the bandwidth allocation, and then logs
in and gets your own channel. Then the authentication procedure and the device are issued IP-address: four-or
six-digit (in a future release.) Calls to the WiMAX network will also implement IP-based, as in Skype - another
similarity with the Wi-Fi-networks.

				
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