Global Sources
EE Times-Asia
Stay in touch with EE Times Asia
EE Times-Asia > RF/Microwave

UWB camp forms SIG, finalizes physical-layer spec

Posted: 06 Sep 2004 ?? ?Print Version ?Bookmark and Share

Keywords:multiband-ofdm alliance? ultrawideband? wireless communications? media access control? mac?

The Multiband-OFDM Alliance has formed a special interest group (SIG) to develop technical specifications based on its version of ultrawideband high-rate, short-range wireless communications.

The group also said it has finalized the physical-layer portion of the spec, and that the MAC layer will be finalized by year's end.

The announcement comes a week after MBOA petitioned the Federal Communications Commission for a waiver of Part 15 rules on UWB, saying a waiver would "permit MB-OFDM technology to compete on an equal footing in the marketplace with other ultrawideband technologies."

The waiver request is the latest twist in an FCC-compliance debate that has lasted over a year in response to MBOA's multiband orthogonal frequency division multiplex (MB-OFDM) approach.

The MBOA-SIG will publish and manage UWB specifications for adoption by the consumer electronics, PC and mobile industries. The SIG will be formally announced at the Intel Developers Forum, where the specifications roadmap will also be disclosed.

The physical-layer specifications were originally scheduled to be completed in May, but the effort was complicated by the MBOA's decision to design a new MAC layer, instead of using an existing 802.15.3 MAC, which was the original intent. Now under review, an MBOA spokeswoman said the physical-layer spec should be available in about 60 days. The MAC layer will be completed by year's end.

Upon completion, the specifications will be made available to member companies. According to the MBOA-SIG, the specification's key attributes include spectral flexibility, the ability to manufacture radios with CMOS process technology, the ability to handle narrowband interference and out-of-band emissions control.

MBOA-SIG promoters include Alereon, Hewlett-Packard, Intel, Nokia, Philips Electronics, Samsung Electronics (SAIT), Staccato Communications, Sony, Texas Instruments and Wisair. While MBOA membership has been freeit has over 170 member companiesa spokeswoman for the group was unsure as to how many paid to join the SIG.

Formation of the SIG builds upon the ecosystem MBOA has been generating around its UWB technology, including relationships with the Wireless USB Promoters Group and the WiMedia Alliance, which will have access to MBOA's PHY and MAC.

Emissions compliance

While the MBOA-SIG specification builds on established OFDM techniques, compliance with FCC testing guidelines remains questionable. Hence, last week's waiver request. The issue surfaced when the IEEE 802.15.3a task group first met in July 2003 to define a physical-layer specification for wireless communications at rates of between 110- (10m) and 480Mbps (1m).

FCC rules require that frequency hopping be turned off when measuring emissions from frequency-hopping systems. According to the rival direct-sequence UWB camp, which is opposing MBOA in the .15.3a standards battle; this affects the range and throughput of MBOA-based devices, preventing them from meeting requirements of the .15.3a standard's project authorization request.

MBOA-SIG has consistently argued that its technique does not use frequency hopping, that the rules were originally written with impulse-radio in mind and that its approach meets the "intent" of the rules in terms of interference emissions requirements.

Stressing that this is a new technology, the FCC has said that if its measurements determine that emissions are not excessive it would consider allowing MB-OFDM radios to operate freely. Those tests are currently underway at ITS Labs. Meanwhile, the agency recently certified Freescale's UWB implementation.

According to Julius Knapp, chief of the FCC's Office of Engineering and Technology, the waiver request issue should be settled quickly. "Comments should be filed by Sept. 29, and replies to those comments are due in by Oct. 14," Knapp said.

While an MBOA spokeswoman said the waiver prevents MB-OFDM-based radios from being stuck in limbo while the debate goes on, a Freescale spokeswoman argued that the waiver request is a MBOA tactic designed to pressure the FCC into approving its approach.

- Patrick Mannion

EE Times

Article Comments - UWB camp forms SIG, finalizes physic...
*? You can enter [0] more charecters.
*Verify code:


Visit Asia Webinars to learn about the latest in technology and get practical design tips.

Back to Top