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IEEE 802.15 is the 15th working group of the IEEE 802 which specializes in Wireless PAN (Personal Area Network) standards. It includes five task groups (numbered from 1 to 5) [1]:

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Task group 1 (WPAN/Bluetooth)

IEEE 802.15.1-2002 has derived a Wireless Personal Area Network standard based on the Bluetooth v1.1 specifications. It includes a medium access control and physical layer specification. An updated version, IEEE 802.15.1-2005, has been published.

Task group 2 (Coexistence)

IEEE 802.15.2-2003 addresses the issue of coexistence of wireless personal area networks (WPAN) with other Wireless Devices operating in Unlicensed Frequency Bands such as wireless local area networks (WLAN).

Task group 3 (High Rate WPAN)

3 (High Rate WPAN)

IEEE 802.15.3-2003 is a MAC and PHY standard for high-rate (11 to 55 Mb/s) WPANs.

3a (WPAN High Rate Alternative PHY)

IEEE 802.15.3a was an attempt to provide a higher speed UWB PHY enhancement amendment to IEEE 802.15.3 for applications which involve imaging and multimedia.

The IEEE 802.15.3a most commendable achievement was the consolidation of 23 UWB PHY specifications into two proposals using : Multi-Band Orthogonal Frequency Division Multiplexing (MB-OFDM) UWB, supported by the WiMedia Alliance, and Direct Sequence – UWB (DS-UWB), supported by the UWB Forum.

On January 19, 2006 IEEE 802.15.3a task group (TG3a) members voted to withdraw the December 2002 project authorization request (PAR) that initiated the development of high data rate UWB standards. The process was in total deadlock. There were two technology proposals on the table backed by two different industry alliances. One of them was willing to move forward with a joint proposal the other was not and had sufficient votes to block forward progress. The task group finally agreed to duke it out in the market place. The Working Group concurred. The technology faces significant regulatory hurdles in addition. This was not a factor in this decision but from a standards perspective it probably was and is too early to write a UWB standard given the regulatory and market uncertainty in the world market. If there is a surviving approach in a year or two and the technology has proven itself to be commercially viable, then IEEE can come back and revisit whether it makes sense to create an IEEE standard.

3b (MAC Amendment)

The IEEE 802.15.3.b is working on an amendment to 802.15.3 to improve implementation and interoprability of the MAC. This will include minor optimizations while preserving backward compatibility. In addition, this amendment will correct errors, clarify ambiguities, and add editorial clarifications.

3c (WPAN Millimeter Wave Alternative PHY)

The IEEE 802.15.3 Task Group 3c (TG3c) was formed in March 2005. TG3c is developing a millimeter-wave-based alternative physical layer (PHY) for the existing 802.15.3 Wireless Personal Area Network (WPAN) Standard 802.15.3-2003. Standard completion is expected for May 2008.

This mmWave WPAN will operate in the new and clear band including 57-64 GHz unlicensed band defined by FCC 47 CFR 15.255. The millimeter-wave WPAN will allow high coexistence (close physical spacing) with all other microwave systems in the 802.15 family of WPANs.

In addition, the millimeter-wave WPAN will allow very high data rate over 2 Gbit/s applications such as high speed internet access, streaming content download (video on demand, HDTV, home theater, etc.), real time streaming and wireless data bus for cable replacement. Optional data rates in excess of 3 Gbit/s will be provided.

Task group 4 (Low Rate WPAN)

4 (Low Rate WPAN)

IEEE 802.15.4-2003 (Low Rate WPAN) deals with low data rate but very long battery life (months or even years) and very low complexity. The first edition of the 802.15.4 standard was released in May 2003. In March 2004, after forming Task Group 4b, task group 4 put itself in hibernation.

The ZigBee set of high level communication protocols is based upon the specification produced by the IEEE 802.15.4 taskgroup.

4a (WPAN Low Rate Alternative PHY)

The principle interest is in providing communications and high precision ranging / location capability (1 meter accuracy and better), high aggregate throughput, and ultra low power; as well as adding scalability to data rates, longer range, and lower power consumption and cost.

In March 2005, IEEE802.15.4a selected a baseline specification. The baseline is two optional PHYs consisting of a UWB Impulse Radio (operating in unlicensed UWB spectrum) and a Chirp Spread Spectrum (operating in unlicensed 2.4GHz spectrum). The UWB Impulse Radio will be able to deliver communications and high precision ranging.

4b (Revisions and Enhancements)

The IEEE 802.15 task group 4b was chartered to create a project for specific enhancements and clarifications to the IEEE 802.15.4-2003 standard, such as resolving ambiguities, reducing unnecessary complexity, increasing flexibility in security key usage, considerations for newly available frequency allocations, and others. IEEE 802.15.4b was approved in June 2006 and was published in September 2006 as IEEE 802.15.4-2006.

Task group 5 (Mesh Networking)

Mesh Networking of Wireless Personal Area Networks (WPANs)

BAN

Body Area Network Interest Group

WNG

Wireless Next Generation Standing Committee

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