by Yulia Bondarenko
WiMAX (Worldwide Interoperability for Microwave Access)
is a wireless communications standard
It is sometimes called
"Wi-Fi on steroids"
Was designed to provide 30 to 40 megabit-per-second data rates
The 2011 update provided up to 1 Gbit/s for fixed stations
IEEE standard - 802.16
Range - 30-mile (50-km) radius from base station Speed - 70 megabits per second Line-of-sight not needed between user and base station Frequency bands - 2 to 11 GHz and 10 to 66 GHz Defines both the MAC and PHY layers and allows multiple PHY-layer specifications
A WiMAX system consists of two parts:
A WiMAX tower, similar in concept to a cell-phone tower One tower covers ~8,000 square km
A WiMAX receiver. The receiver and antenna could be a small box or PCMCIA card, or they could be built into a laptop the way WiFi access is today.
A WiMAX tower station can connect directly to the Internet using a high-bandwidth, wired connection (for example, a T3 line). It can also connect to another WiMAX tower using a line-of-sight, microwave link.
This connection to a second tower, along with the ability of a single tower to cover up to 8,000 square kilometers is what allows WiMAX to provide coverage to remote rural areas.
There is the non-line-of-sight, WiFi sort of service, where a small antenna on your computer connects to the tower.
In this mode, WiMAX uses a lower frequency range - 2 GHz to 11 GHz (similar to WiFi). Lower-wavelength transmissions are not as easily disrupted by physical obstructions - they are better able to diffract, or bend, around obstacles.
There is line-of-sight service, where a fixed dish antenna points straight at the WiMAX tower from a rooftop or pole. The line-of-sight connection is stronger and more stable, so it's able to send a lot of data with fewer errors.
Line-of-sight transmissions use higher frequencies, with ranges reaching a possible 66 GHz. At higher frequencies, there is less interference and lots more bandwidth.
WiMax versus Wi-Fi
Maximum speed: Wi-Fi - up to 54 megabits per second under optimal conditions WiMax - should be able to handle up to 70 megabits per second. Maximum range: Wi-Fi - 30 meters WiMax will blanket a radius of 30 miles (50 km) with wireless access.
Thank you for your attention! :)