802.16 standards

The standards board of the IEEE (Institute of Electrical and Electronics Engineers) based in the USA set up a working group to address Broadband Wireless Access Standards under the 802.16 banner. Its aim was to prepare formal standards that would be used for the deployment of broadband metropolitan area networks around the world.

Although the standards for the physical and MAC layers are defined under 802.16, the technology has been named WiMAX (Worldwide interoperability of Microwave Access) and issues, including interoperability, certification and promotion of the system are handled by the WiMAX Forum.

802.16 History

The 802.16 working group was set up by the IEEE in 1999 under the IEEE 802 LAN/MAN Standards Committee. The first 802.16 standard was approved in December 2001and this was followed by two amendments to the basic 802.16 standard. These amendments addressed issues of radio spectrum and interoperability and came under the designations 802.16a and 802.16c.

In September 2003 a major revision project was commenced. This had the aim of aligning the standard with the European / ETSI HIPERMAN standard. It was also intended to incorporate conformance test specifications. The project was completed in 2004 and the standard was released as 802.16d, although it is often referred to as 802.16-2004 in view of the release date. With the release of the 802.16-2004 standard, the previous 802.16 documents, including the a, b, and c amendments were withdrawn.

Relationship with WiMAX Forum

The WiMAX Forum was formed in June 2001. Its aim is to promote and certify compatibility and interoperability of broadband wireless products. In particular its focus is on the IEEE 802.16 standard which has been aligned with the ETSI HiperMAN standard. In this role the WiMAX Forum works wit the IEEE 802.16 working group.

802.16 Standards and Amendments

Although the original 802.16 standard along with amendments a, b, and c are now withdrawn, there are still many documents that are being used for defining and evolving the 802.16 standard. A summary of the major documents, including those that have been withdrawn is given below:

Standard / amendment	Comments
802.16	Now withdrawn. This is the basic 802.16 standard that was released in 2001. It provided for basic high data links at frequencies between 11 and 60 GHz.
802.16a	Now withdrawn. This amendment addressed certain spectrum issues and enabled the standard to be used at frequencies below the 11 GHz minimum of the original standard.
802.16b	Now withdrawn. It increased the spectrum that was specified to include frequencies between 5 and 6 GHz while also providing for Quality of Service aspects.
802.16c	Now withdrawn. This amendment to 802.16 provided a system profile for operating between 10 and 66 GHz and provided more details for operations within this range. The aim was to enable greater levels of interoperability.
802.16d (802.16-2004)	This amendment was also known as 802.16-2004 in view of the fact that it was released in 2004. It was a major revision of the 802.16 standard and upon its release, all previous documents were withdrawn. The standard / amendment provided a number of fixes and improvements to 802.16a including the use of 256 carrier OFDM. Profiles for compliance testing are also provided, and the standard was aligned with the ETSI HiperMAN standard to allow for global deployment. The standard only addressed fixed operation.
802.16e (802.16-2005)	This standard, also known as 802.16-2005 in view of its release date, provided for nomadic and mobile use. With lower data rates of 15 Mbps against to 70 Mbps of 802.16d, it enabled full nomadic and mobile use including handover.
802.16f	Management information base
802.16g	Management plane procedures and services
802.16h	Improved coexistence mechanisms for license-exempt operation
802.16j	Multi-hop relay specification
802.16k	802.16 bridging
802.16m	Advanced air interface. This amendment is looking toth e future and it is anticipated it will provide data rates of 100 Mbps for mobile applications and 1 Gbps for fixed applications. It will allow cellular, macro and micro cell coverage, with currently there are no restrictions on the RF bandwidth although it is expected to be 20 MHz or more.

Summary

In view of the fact that it is necessary for standards such as 802.16 to continually move forward, further amendments and documents will be issued as new development take place. Only by taking account of the way in which technology is moving and the new requirements for 802.16, can it keep pace with the needs of the users. One good example of a standard that has evolved is Ethernet. This standard has remained in use for many years, and will do so for many years to come. This has been achieved by simply upgrading the standard to keep pace with the needs of the users. In this way it has been the major networking standard for over 30 years. This too could be true for 802.16.