Wave of the Future or Dead in the Water? The Public Release of DARPA's XG Spectrum Sharing Technology

The Defense Advanced Research Projects Agency (DARPA) NeXt Generation (XG) Communications program is developing technology to allow multiple users to share spectrum in ways previously unimaginable or at least thought impractical. The policy implications of XG are vast. The technology implies that there is vast "white space" in frequency bands frequently thought to be fully occupied. Incumbent licensees who have argued that there is no underutilized spectrum within their frequency bands will now have to face stark evidence to the contrary.

Like DARPA's early work on the Internet, XG technology is applicable not only to military but also civilian applications. Accordingly, it has been said to be "the mother of all sharing protocols." It is designed to co-exist with and complement sharing protocols included in today's Wi-Fi technologies (802.11, 802.16, and 802.20 wireless standards) -- but also to allow these and future unlicensed wireless devices to operate throughout the spectrum, including in the most desirable low frequencies that are so grossly underutilized today.

Preston Marhall will use New America's Forum to publicly release XG's first detailed specification. Specifically, he is releasing a formal Request for Comment (RFC), the first in what will be a series of technical descriptions for key aspects of the XG technology. DARPA is making these documents available for community input in order to ensure that the resulting XG technology is widely applicable and its principles of sharing incorporated into spectrum policy. DARPA calls this RFC "the first step in establishing methods for enabling shared spectrum usage."

XG is expected to increase spectrum efficiency by an order of magnitude or more. XG technology allows the military to go overseas and set up a telecommunications network on the fly without interfering with existing spectrum users. And if the military uses this technology overseas, which is its primary application, the U.S. must face the obvious charge of a double standard. Why should the U.S. be able to use unused spectrum overseas without allowing the same capability domestically?

Participants

• Preston Marshall
  Program Manager, DARPA Advanced Technology Office


• Ed Thomas
  Former Chief, FCC Office of Engineering and Technology


• Mark McHenry
  President, Shared Spectrum Company; and former Program Manager, Defense Advanced Research Projects Agency (DARPA)


• Kalle Kontson
  Member, FCC Technology Advisory Committee
  Author, Transceiver Bill of Rights


• J.H. Snider
  Senior Research Fellow