Broadcasters and makers of TV white-space devices have come
to the table to solve a potential interference problem, according to the
National Association of Broadcasters.
“NAB and the TV band
device manufacturers recommend that all TV band devices incorporate automatic
geolocation capability or be under the control of a device that includes that
capability,” the parties wrote in a joint letter to Julius Knapp, chief of the
Federal Communications Commission’s Office of Engineering and Technology.
The concurring device makers include Adaptrum, Carlson Wireless Technologies,
KTS Wireless and Meld Technology, which together represent more than 95 percent
of deployed devices registered in the FCC’s white-space databases.
The databases were designed to prevent the unlicensed TVWS devices from
interfering with TV signals and depended on manually entered geographic
coordinates. When the FCC proposed allowing the operation of unlicensed devices
in unoccupied TV channels in 2009, broadcasters lobbied it to require
geolocation and spectrum-sensing technology in the devices. Device makers
balked at the associated expense and the commission declined.
Several database administrators were approved over time (including Google
) and TVWS
devices slowly deployed. The NAB’s Bruce Franca started poking through the
databases last year and found that about one-third of registered TVWS devices
had incorrect location information, including open fields, single-family homes
and foreign countries.
As a result, a TVWS device could be operated in Los Angeles, where there are
virtually no open frequencies, simply by registering it elsewhere in the
The NAB subsequently petitioned the FCC to shut down the databases and fix
them. (See “NAB
Petitions FCC to Shut Down White Space Database.”
) The NAB and the
device makers are now asking the FCC to change the rules to reflect the
inclusion of geolocation technology that will tell
the databases where the device is being used. They recommend
that, “all TV band devices incorporate automatic geolocation capability or be
under the control of a device that includes that capability.” The geolocation
technology would be accurate within 100 meters.
The parties suggested that existing inventory be grandfathered and be allowed
to continue working through the transitional period, and to require geolocation
compliance one year after the rules are modified, or Jan. 31, 2017, whichever