Ultrawideband—a technology in which signals are transmitted in the form of billions of extremely short radio pulses spread over a bandwidth totaling several gigahertz—is highly anticipated because it will provide the wireless personal-area-network (WPAN) connectivity of Bluetooth, but at speeds up to 500 times faster.

Despite that promise, a growing rift between the backers of separate ultrawideband (UWB) technologies has led to a stalemate within the IEEE 802.15.3a working group for WPAN charged with finalizing a standard for ultra-wideband. The two groups at loggerheads are the Multiband-OFDM Alliance (MBOA), led by Intel Corp., in Santa Clara, Calif., and the XtremeSpectrum group, led by Motorola Inc., in Schaumburg, Ill. (Motorola recently purchased XtremeSpectrum, which was based in Vienna, Va.) Their main disagreements concern how much UWB devices might interfere with other radio users, how much power they will consume, and how much the chipsets needed to relay UWB signals between devices will cost.

Athough the groups have made repeated attempts to reach a compromise, the process has bogged down. Andreas F. Molisch (SM), a researcher at Mitsubishi Electric Research Laboratories, in Cambridge, Mass., told IEEE Spectrum that "the two proposals are so far apart technologically that, in the end, it's going to be one or the other."

At the most recent meeting of the IEEE 802.15.3a working group, held in Albuquerque, N.M., during the week that ended 14 November, MBOA's proposal received 58 percent of the votes—well short of the 75 percent needed for ratification.