30 April 2009

What is Wimax?


Definition: WiMaX is simply 'Worldwide Interoperability Microwave Access'
According to WiMAX forum "WiMAX is a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL. WiMAX will provide fixed, nomadic, portable, and, eventually, mobile wireless broadband connectivity without the need for direct line-of-sight to a base station. In a typical cell radius deployment of 3 to 10 kilometres, WiMAX Forum Certified systems can be expected to deliver capacity of up to 40 Mbps per channel, for fixed and portable access applications." (WiMax Forum, 2007)


In the WiMAX terminology, portable access means you can access WiMAX networks from different locations, but not necessarily while moving. Mobile WiMAX is accessible while on the move.


From this definition, we can see why WiMAX has been such a trendy topic in the wireless industry. The capability to provide multiple channels at 40 Mbps for cell sizes from 3 to 10 kilometres is well above what can be accomplished with standard 801.llg or 802.lla wireless point-to-point. In addition, non-line-of-sight (NLOS) features of some WiMAX technologies provide the possibility for better coverage in wooded or congested areas.


A WiMAX network consists of two major components: a base station and a subscriber station. Base stations provide connectivity to one or more subscriber stations and are implemented by service providers to provide Internet, voice, video or Wireless Area Network (WAN) link access.


These base stations are similar to Wi-Fi Access Points (APs) as they provide centralized access to back end connected networks. They use different standards than Wi-Fi, however, so the evaluation ends there. While subscriber stations are uniquely designed for 802.16 networks, the reality is that they provide a connection to the network and you can still route internal 802.11 devices through the 802.16 subscriber station for network access.