WiMAX Standards

WiMAX standards are the operational descriptions, procedures or tests that allow manufacturers to produce devices that reliably operate and can work with devices produced by other manufacturers. The development of WiMAX standards is overseen by the Institute of Electrical and Electronics Engineers (IEEE).

The WiMAX standard is given the standard identifier of 802.16 (there are several variations of 802.16). 802.16 specifications primarily cover the lower layers including the physical layer and media access control (MAC) layer and define the different levels of quality of service (QoS) that can be provided.

Even within the WiMAX specification, there are multiple radio interface types. The need for these variations is typically the result of different industry requirements such as fixed point to point communications or mobile broadband communications, which require tradeoffs in radio access types in exchange for key requirements such as mobility, higher speed data communication rates or longer transmission distance.

To enable the 802.16 system to provide mobile operation (not fixed location), the 802.16e specification was created and released in 2006. 802.16e defines mobile broadband operation in the 2-6 GHz frequency range. 802.16e added mobility management, extensible authentication protocol (EAP), handoff (call transfer), and power saving sleep modes to the WiMAX system.

In addition to the basic 802.16 radio interface specifications, several other 802.16 specifications have been created to the standards of the network and operation of WiMAX devices and systems.

802.16f is an IEEE standard that defines the network management information base (MIB) parts that are used for the 802.16 WiMAX system. 802.16g is an IEEE standard that defines the management processes (management plane) that are used for the 802.16 WiMAX system. 802.16.2-2004 is an IEEE standard that defines how to plan and setup broadband radio transmitters in 802.16 systems so they can co-exist.

Figure 1 offers a comparison between the original fixed WiMAX standard and the WiMAX standard that can be used for fixed, mobile and portable. This table shows that the original 802.16 standard was released in 2004 and it was only capable of providing fixed wireless data services. It used OFDM modulation and could be deployed in both TDD or FDD formats. The 802.16e standard was released in 2005 (now merged into the original 802.16 standard) was designed for fixed, mobile and portable operation. It used OFDMA modulation with TDD and optionally FDD duplexing capability.

Figure 1: WiMax Standards

Figure 2 depicts the evolution of the 802.16 wireless broadband specification over time. The original 802.16 specification offered fixed wireless broadband service at 10-66 GHz. To provide fixed wireless broadband in the 2-11 GHz range, the 802.16a specification was created. Additional variations of the original 802.16 specification were created until in 2004, these specifications were merged into a single 802.16-2004 main specification. Since the 802.16-2004 specification was released, an 802.16e addendum was approved that adds portability to the 802.16 WiMAX system.

Figure 2: Wireless Broadband 802.16 Evolution