WASHINGTON—The National Association of Broadcasters is urging the FCC to stop dithering and make a final decision on its proposal to use a terrain-based model to determine channel availability for TV white spaces and criticizing TVWS proponent Microsoft for providing an inadequate case for widening availability. 

NAB’s comments were made during a conference call with the FCC last week in which it repeated its claims that the terrain-based model—supported by Microsoft—could lead to harmful interference to licensed television stations and that the company has failed to offer technical evidence for its position.

Plus: NAB Questions FCC’s Proposed TV White Space Measurement Model

“The only real technical support Microsoft has offered for its proposal is a citation to studies it submitted in the initial phase of this proceeding purporting to demonstrate that ATSC 1.0 and ATSC 3.0 receivers might be more robust to adjacent-channel interference than the Commission’s rules suggest,” NAB said. “However, NAB noted almost a year ago that Microsoft conducted testing using only new ATSC 1.0 receivers, completely ignoring older receivers, and that the sole ATSC 3.0 receiver Microsoft tested was a $1,000 dongle marketed as a ‘professional grade’ receiver.

“Microsoft has not even attempted to respond in its latest filing, making its reference to its limited testing disingenuous,” the association added. 

NAB also said TVWS proponents are grossly exaggerating the success of TV white spaces, accusing advocates of citing “expanded” white space deployments that don’t actually exist. It said the Public Interest Spectrum Coalition has cited pilot programs in Colorado, Virginia and Nebraska that were expanded in response to increasing the availability of distance learning opportunities during the pandemic of the past year, when in fact there was no evidence in the TVWS database of white space devices being used in Colorado or Nebraska and just a smattering in rural Virginia. 

NAB added that after a dozen years of FCC activity on TVWS, that there are only about 300 such devices operating nationally.  

“It is long past time for the Commission to stop tinkering with its rules to boost a technology that has no demonstrated track record of success,” NAB said. “At some point, white spaces proponents should be asked to actually accomplish something before asking for further handouts.” 

WASHINGTON—NAB is continuing its fight to protect TV White Space, with its latest comments to the FCC questioning the methodology that the commission will use for determining TV White Space channel availability.

In comments filed on March 29, NAB praised the FCC’s efforts in recent years that have allowed TV to evolve with new services like NextGen TV and distributed transmission systems (DTS), enabling broadcasters to better serve the public. At the same time, the FCC has loosened rules for TV White Space devices, including recently authorizing higher power levels, among other things.

Because of these factors, the NAB does not believe that now is the time to change the method to determine channel availability that was proposed in a Further Notice of Proposed Rulemaking. The FNPRM calls for a switch to a deterministic terrain-based model.

“Using deterministic terrain-based models could risk more interference in the very areas where television coverage is already challenging at the very moment when broadcasters are trying to improve it,” NAB’s comments read. “We urge the Commission to reject this proposal.”

PLUS: NAB to FCC: Don’t Authorize Client-to-Client Communication in 6 GHz Band

The goal for switching to a terrain-based model, according to NAB, is for greater accuracy in determining channel availability than the current method of referencing a station’s protected contour. NAB does not believe this will be the case, calling point-to-point terrain-based models results superficial that overstates the true accuracy of terrain-based models with respect to individual TV receivers.

“Models, including Longley-Rice, may be broadly accurate on average but will inarguably be inaccurate in individual real-world cases,” NAB wrote. “Terrain-based models do not, and are not intended to, reliably predict signal levels (whether desired or undesired) at specific locations. Rather, they predict only qualified results with a typical confidence level of just 50 percent. Stated different, these are blunt instruments that may be broadly accurate over a large number of predictions but are wildly inaccurate in specific situations.”

Two reasons why the NAB believes these models will not work is because first, coverage in the real world cannot be perfectly planned, and second, there is no accurate way to determine the precise location of individual TV receivers that might allow for more granular determinations of coverage. NAB specifically cites ATSC 3.0 as an example of this, saying NextGen TV deployments will prove complicated for terrain-based models.

PLUS: NAB Brands Efforts to Expand Unlicensed Access in 6 GHz Band as ‘Premature’

Overall, NAB does not believe that now is the right time for a switch like the one proposed in the FNPRM to take place.

“[E]ven if the Commission were convinced that there is some small degree of marginally improved accuracy to be gained by relying on terrain-based models to determine channel availability (which there is not) this would be the wrong time to make such a change. At a minimum, we urge the Commission to wait until it has a clearer picture of: (1) the changes to the noise floor caused by relaxed TVWS rules; and (2) the evolving state of coverage as broadcasters continue to deploy ATSC 3.0 service.”

NAB’s complete comments can be found through the FCC’s Electronic Comment Filing System. 

ARLINGTON, Va.—The Consumer Technology Association has officially put its support behind the FCC’s proposal that would allow for great use of TV white spaces (TVWS) by unlicensed white space devices, increasing broadband services in rural and underserved areas, it says.

The FCC submitted a Notice of Proposed Rulemaking on expanding the use of TVWS, which is portions of the broadcast TV band not actively used by TV stations, back in February; it was passed unanimously by FCC Chairman Ajit Pai and the FCC commissioners.

Politicians and organizations like the NAB have said that they support the effort, at the very least in most of its details.

CTA argues that the current coronavirus pandemic has highlighted the need for this proposal, specifically how “every household needs access to affordable broadband to connect to work, education, entertainment and life-saving technologies.”

“We applaud adoption of the NPRM and urge the commission to adopt the proposals therein—which reflect consensus between the unlicensed and broadcast communities,” CTA said.

The entire CTA letter is available on its website. 

WASHINGTON—Two U.S. senators are urging the FCC to move forward with its proposal to allow wireless companies to operate within unused spectrum in the TV bands to provide wireless broadband access to rural areas. 

In February, the FCC unanimously issued a Notice of Proposed Rulemaking that would update the FCC’s rules regarding white spaces—the portions of broadcast television bands that are not used by TV stations (aka “TVWS”)—to allow “for more robust service and efficient use of white space devices particularly in rural areas, without increasing the risk of harmful interference to protected services in the TV bands.”

Hailing from two rural states, the senators, Kevin Cramer (R-N.D.) and Angus King (I-Maine) pointed to the “digital divide” facing rural areas when it comes to accessing high-speed broadband.

“Many of our constituents who live in remote and rural areas without access to reliable broadband internet face immense challenges in all aspects of their lives,” they wrote to the FCC. “The digital divide is holding back too many students, seniors, farmers, small businesses and Indian reservations in our home states. These members of our community deserve the same opportunities as our constituents living in connected urban and suburban areas.”

The senators mentioned specific applications important to rural areas such as “precision agriculture” and moving platforms such as school buses that could arise from the use of TVWS. They also cited the importance of TVWS spectrum, “which allows for better coverage with signals travelling further and penetrating trees and walls better than other spectrum bands.” 

Broadcasters have urged the FCC to tread carefully on allowing the use of white spaces, warning that without proper regulatory oversight, this portion of the spectrum band could interfere with over-the-air broadcast signals.  

“By updating its TVWS spectrum rules, the commission would allow for more flexibility and uses of TVWS technology enabling greater broadband opportunities like the Internet of Things (IoT) and better broadband service coverage by increased antenna height and power, while also protecting licensed incumbents,” the senators told the FCC. 

This story has been updated with a statement from NAB.

WASHINGTON—FCC Chairman Ajit Pai has presented a new proposal that would provide additional opportunities for unlicensed white space devices to deliver wireless broadband services in the spectrum previously marked for broadcast television bands (channels 2-35).

Back in March of 2019, the FCC approved the use of white spaces between TV channels by fixed and wireless mobile devices, specifically unused channels, channel 37, guard bands between wireless spectrum and between uplink and downlink spectrum in the 600 MHz band. The goal of this was to increase broadband services in rural areas.

That is the same goal of Pai’s new proposal, which he revealed to the FCC commissioners on Wednesday, Feb. 5, and has marked for a vote at the FCC’s monthly Open Meeting on Feb. 28.

With this new proposal, Pai wants to permit higher transmit power and higher antennas for fixed white space devices in rural areas. He argues that it will allow white space devices to reach users at greater distances for improved broadband coverage. It would also enable signals to better penetrate foliage, buildings and other obstacles. In addition, it would permit higher power mobile operators within geo-fenced areas and proposes rule revisions to facilitate the development of “new and innovative narrowband Internet of Things-based services.”

With the requirement that white space device operations protect other authorized services from interference, Pai also has proposed increasing the minimum required separation distance for white space devices operating at higher power.

“TV white spaces can play a critical role in providing broadband services to rural and underserved areas,” Pai said. “The FCC has taken steps to enable the use of white spaces over the years, and this new proposal would further help bridge the digital divide while protecting TV stations.”

NAB's Executive Vice President of Communications Dennis Wharton released the following statement regarding Pai's new proposal:

"NAB appreciates the consensus-based approach the FCC is taking in this proceeding. We look forward to working with the commission and other stakeholders to develop final rules that will allow more flexibility for rural white spaces operations while protecting broadcasters."

If approved at the Feb. 28 meeting, the public will be able to provide feedback to this Notice of Proposed Rulemaking prior to any official adoption.

WASHINGTON—NAB told the FCC this week in comments responding to a Petition for Rulemaking filed by Microsoft regarding changes to Television White Space rules that it can support four out of five of the technology company’s requested modifications, which the association wishes to see as part of “a focused Further Notice of Proposed Rulemaking.”

Agreement centers on higher power limits for TVWS operation in rural areas, antenna height, allowing geofenced and fixed TVWS operations on mobile platforms and use of TVWS for narrowband Internet of Things IoT applications.

However, NAB urged the commission to postpone consideration of a rule change sought by Microsoft to authorize higher power operations on first-adjacent channels to TV broadcasters until the transition to Next Gen TV services has advanced.

NAB agrees with a Microsoft proposal to boost TVWS radiated power in rural areas from the EIRP limit of 40 dBm to 42 dBm in areas where at least half of the allocated TV channels within the intended band of operation are unused for TV service and available for white space use and a fixed white space device is sufficiently separated from protected operations.

The association also agrees with the company’s proposal to allow TVWS operation from antennas 500 meters above average terrain subject to a couple of restrictions to protect broadcasters. Those include adjusting the distance separating the antennas from protected services in line with existing commission methodology and a special coordination requirement for antennas higher than 250 meters.

In accepting Microsoft’s geofencing proposal, NAB noted that existing rules allow geofenced operations for Mode II personal/portable TVWS devices. The company is seeking “an analogous rule that would permit fixed TVWS operations on platforms (such as vehicles) that operate within a pre-defined area on channels determined [to be] using the interference protection rules that would apply throughout that area,” NAB said in its filing.

These devices would be required to check their location every 60 seconds while in operation and could not be located on aircrafts, ships or satellites, the filing noted. They also would be restricted from using channel availability information when within 1.6 km of the boundary defined for their operation.

Related to rules supporting TVWS use for narrowband IoT applications, the tech giant is seeking several rule changes to allow simultaneous narrowband transmissions so long as they do not “aggregate to produce total conducted power levels above what the Commission’s rules presently allow in a 6 MHz-wide channel,” the NAB filing noted.

Proposed protections include a listen-before-talk requirement, a ban on continuous video or audio transmission with a maximum transmission limit of 10 seconds per hour and a limit on total power density in any 100 kHz slice of a 6 MHz channel “to no more than existing limits for TVWS operations adjusted for that bandwidth,” the filing said. Subject to these protections, NAB supports the company’s proposal, it added.

However, NAB disagrees with Microsoft’s proposal to authorize higher power operations on first-adjacent channels to TV broadcasters. “Microsoft bases this proposal in part on the assumption that Next Gen TV receivers ‘will be more robust to adjacent-channel interference than the ATSC 1.0 receivers’” the agency previously analyzed. Further, the need to upgrade to new DTV receivers as part of the Next Gen TV transition offers an opportunity to “reduce their susceptibility to adjacent-channel interference,” the association recounted from the Microsoft petition.

In its comments, NAB rejected these assertions, saying “there is no evidence that Next Gen TV receivers will prove less susceptible to interference than existing receivers.” Even if this were true, the Microsoft proposal is “premature” until the installed base of DTVs is replaced with 3.0 receivers, NAB said.

The association added that requiring consumer electronics manufacturers to build receivers that are more robust to accommodate TVWS operation on channels adjacent to those in use by broadcasters is “unsupported.”

Including this proposal in the proceeding will only create delays, NAB said, adding that the agency can take up the proposal “when the Next Gen transition has made further progress and Microsoft’s assumptions regarding receivers can be verified or disproven.”

BEAVERTON, ORE.—A new model of rules pertaining to TV White Space technology has been issued by the Dynamic Spectrum Alliance, replacing the original published version from 2014. The updated rules are meant to offer higher availability for dynamic spectrum devices and stronger protection for incumbent users, as well as close the digital gap in rural communities, claims DSA.

DSA says it based the new model rules off of regulatory environments used by Ofcom in the U.K. and the FCC in the U.S.; it also incorporated learnings from the operation of TVWS networks, including DSA member Nominet.

Part of the update rules enable flexible network topologies such as mesh networks, TVWS in high-speed, long-distance scenarios, and a streamlined regulatory framework to facilitate market growth. DSA says the rules are put in place to ensure that TVWS users will not cause interference to incumbent users.

“The Alliance has long been championing TVWS technology to connect those in underserved and rural locations, which will in turn help the digital divide,” said Kalpak Gude, president of the DSA.

The new rules are now available and can be found here.