Worldwide Interoperability for Microwave Access (WiMAX)

Worldwide Interoperability for Microwave Access (WiMAX), is a wireless microwave technology based on the IEEE 802.16 standards. It was originally published in 2001 by WiMAX forum, the version which is now called fixed WiMAX. It is similar to Wi-Fi, though it provides higher data rates up to 1 Gbps even at distances of 30 miles.

WiMAX forum defines WiMAX as – A standards-based technology enabling the delivery of last-mile wireless broadband access as an alternative to cable and DSL.

Features of WiMAX

• WiMAX is a coalition of wireless industry based upon IEEE 802.16 standards.

• It aims for the advancement of broadband wireless access (BWA) networks.

• The IEEE 802.16 lays down the standards for both physical layer as well as a medium access control (MAC) layer for WiMAX.

• WiMAX initially provided data rates of 30 – 40 Mbps. The updated version that came in 2011 provides up to 1 Gbps data rates for fixed stations.

• The latest version of WiMAX is WiMAX release 2.1, popularly known as WiMAX 2+.

• WiMAX is comparable to Wi-Fi technology and so is nicknamed as "Wi-Fi on steroids." However, WiMAX provides much higher data rates, is used for outdoor networks, and uses IEEE 802.16 standards in contrast to IEEE 802.11 standards of Wi-Fi.

• It operates in the frequency band of 2 GHz to 11 GHz. The bandwidth is dynamically allocated as per user requirements.

• WiMAX uses orthogonal frequency division multiplexing (OFDM) with 256- channels.

• It uses convolutional codes, particularly Reed – Solomon Codes for forward error correction (FEC) to deal with damaged frames.

• The application of WiMAX is greatly in areas where broadband cables are not accessible. WiMAX can also be used for VoIP phone calls and IPTV.