Check out NTIA’s new & improved spectrum compendium detailing federal spectrum uses. Now with better search tools! http://t.co/5JZ7mfXlwq

— NTIA (@NTIAgov) May 7, 2015

With the above tweet NTIA announced a major improvement to its publicly available information on federal spectrum use. The information below from the new page describes the type of information now available:



For the bands between 225 MHz and 5 GHz the new site gives details on US allocations, number of NTIA assignments for federal users, and future federal plans for the bands.

The table at left shows the type of data available and its limitations. For the first time we can remember NTIA has revealed large amounts of data on federal assignments (equivalent to licenses in FCC jargon). As the table notes:

“The number of actual systems, or number of equipments, may exceed and sometimes far exceed, the number of frequency assignments in a band. Also, a frequency assignment may represent, a local, state, regional, or nationwide authorization. Therefore, care must be taken in evaluating bands strictly on the basis of assignment counts or percentages of assignments.”

The reason for this is that NTIA’s record keeping has evolved over decades and in ancient history agencies could get nationwide assignments for an unlimited amount of transmitters in an unlimited number of locations. I recall that the spectrum enforcement site of FCC, the part now slated for a huge staffing cut, has 3 UHF land mobile channels on such a nationwide basis even though I doubt it ever had 300 mobile radios. But in the early days assignments were “free” and even now agencies pay NTIA only for the number of assignments, not the number of transmitters or locations. Clearly many IRAC members do not want this to change so NTIA probably doesn’t have better information on the number of federal transmitters and it many cases does not know where that are.

It is also unclear if these numbers include classified assignments.

What is missing? Those of us who are fans of Benn Kobb’s now out of print, but available on Kindle, Wireless Spectrum Finder, will miss common names for many federal systems, although the section that includes GPS calls it “GPS”.


More importantly, there is no indication on where each assignment is used or how heavily it is used. Much federal spectrum use is outside of urbanized area where there is the greatest demand for new spectrum. Thus having some knowledge, even any knowledge of which bands are used in urban areas and which are more often used in rural areas would be very helpful.

We have criticized NTIA in the past for not publishing spectrum occupancy data in certain bands and we have also printed an apology and correction when NTIA pointed out we missed some data they had published. But the new pages do not contain any links to previously published NTIA data on band occupancy or data from any other sources like the IIT Spectrum Observatory. While it is unlikely NTIA will cite such private sector data, it is puzzling why published NTIA data is not cross-referenced.

Is “sharing is the new normal” more information on intensity of use and general geographic nature of use would be very helpful in improving national spectrum management policy.

While spectrum below 5 GHz is of prime interest in the cellular industry’s endless appetite for more spectrum, spectrum above 95 GHz that presently lacks any FCC rules for commercial use is all shared with federal users and there is no real public data on what is going on there. In order to facilitate commercial evolution in that spectrum we urge NTIA to make some information available on present and planned spectrum uses for federal users and sharing potentials.

But we congratulate NTIA on a positive step forward with the new information.

Tags: NTIA Reform, NTIA

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