A spokesperson at Freescale also confirmed for EE Times that Motorola is also pulling out.

The forum was founded in 2004 in an effort to rally support around Freescale's direct-sequence flavor of wireless ultrawideband signaling—and to compete with what has now become the WiMedia Alliance. The alliance is led by heavyweights such as Intel and Philips, as well as a host of startups including Staccato, Alereon and WiQuest. It uses a flavor of UWB based on multiband orthogonal frequency division multiplexing (MB-OFDM).

Freescale's decision to pull out was not unexpected. According to Martin Rofheart, director of Freescale's UWB operations, the decision was motivated by the company's need to focus completely on the wireless USB application, which it calls Cable Free USB.

The WiMedia Alliance calls its own drive in that direction Wireless USB.

"The forum was de-focused with concerns such as regulations, certification, interoperability and common signaling [schemes]," said Rofheart. "We don't think anything else matters for UWB more than our approach with [Cable Free] USB 2.0. We're showing our hand: the battle for UWB is on. We're pulling out of every effort not related to it."

Rofheart and Freescale are betting on its complete solution for unwiring USB 2.0, versus the WiMedia Alliance's approach, which Rofheart said requires the designer to add hardware, software and protocol stacks. "They need to put the reference design on a Cardbus card (to accommodate the additional requirements), while we have a dongle," he said.

Though Freescale and now Motorola are pulling out of the forum, Pulse-Link is staying in.

"The UWB Forum is not made up of one or two companies, it has been and continues to be a federation of companies, groups and organizations promoting the virtues of true impulse base UWB technology that will continue," stated John Santhoff, founder and chief technology officer at Pulse-Link (Carlsbad, Calif.).

Santhoff added: "The UWB forum has over 100+ members of which Freescale has been but one. Pulse-Link continues to support the UWB Forum and the virtues of true impulse based UWB for the delivery of digital content throughout the home."

Regardless, Rofheart is confident that some forum members will join its independent effort. While that effort for now is focused on Cable Free USB, Rofheart said that focus will soon encompass wireless 1394 for home networking and also HDMI (High Definition Multimedia Interface).

The initial designs will use the company's 110-Mbit/s technology based on its XS110 chipset, but Rofheart said the company is readying its next-generation chips that will cater to USB's 480-Mbit/s rates.

"It's simply going through activities for productization," he said.