Sony Pixel Power calrec Sony

DTV Interference, Repacking and the FCC

20/02/2015

These are the eleven scenarios for the 600 MHz Band Plan of the FCC.

ALEXANDRIA, VA. After working for decades in the wide-open spaces of hundreds of megahertz of spectrum, broadcasters will soon be forced into less than half of its traditional frequency allocation. They might end up getting less than one-third. As stations squeeze into the remaining channels and leaving aside the discussion about the cost and effort to do this retuning chances for serious interference will multiply. There are many different kinds of interference and none are good, and all hold risks to broadcasters in terms of viewer coverage and viewing experience.

Charles W. Rhodes is a much-respected expert in television transmission and interference, and even has his own laboratory to test receivers and other components for operational performance. Rhodes is a regular columnist for Broadcast Engineering Extra's sister publication, TV Technology.

BE Extra: As the TV spectrum shrinks and goes through repacking, what is the single most important concern with respect to DTV interference? Assuming less spectrum is permanent, is there a reasonable interference fix?

Rhodes: After the UHF band is truncated, there will be between six and 23 UHF channels remaining. There will be no changes to the VHF bands, except that there will be more stations in the VHF bands. The number of channels remaining in the UHF band will be determined by two factors given in my Feb. 4th column in TV Technology magazine, ( Eleven FCC Scenarios for The 600 MHz Band Plan. ) How many stations will remain on-the-air after repacking is another unknown, but it is obvious to me that the number of stations per channel will increase. With that increased density of stations, there will be more signals and hence more possibilities for interference.

The FCC recognized two kinds of interference to ATSC signal reception: co-channel interference (CCI) and adjacent channel interference (ACI). Other interference mechanisms are well known to TV engineers. These are caused by the presence of one or several strong signals that are offset in frequency from the desired ATSC signal by more than one channel. The proposed 600 MHz band plan includes guard bands to minimize such interference, provided that there is one and not more than one strong undesired signal on nearby channels. With two or more strong undesired signals, you have a whole new ball game, one which the FCC has not to date taken into account.

Recently, two major stakeholders have filed comments with the FCC over these additional interferences. (The Consumer Electronics Association and CTIA: The Wireless Association) Both urge the FCC to get more facts about the effect on broadcasters of these additional interference mechanisms. The problem is, until the outcome of the spectrum auctions are known, it may be impossible to determine the extent of additional interference to the more than 100 million ATSC receivers and converter boxes now serving the public.

Charles W. Rhodes

BE Extra: Is the FCC paying enough attention to potential DTV interference issues? What can be done to get the FCC to understand the problem and take it seriously?

Rhodes: The FCC concluded in 1995 that interference from an undesired signal other than CCI or ACI would not be a problem. They have continued steadfastly to hold that view. I believe that the FCC technical staff understands these problems, which are well known in the technical literature (IEEE Transactions on Broadcasting, and IEEE Transactions on Consumer Electronics and in TV Technology magazine).

BE Extra: There have been a couple of tests of proposed over-the-air ATSC 3.0 systems. Do you have any sense if these will be better/worse/same with regard to interference concerns?

Rhodes: I cannot comment on ATSC 3.0 tests, as I have not been involved.

BE Extra: Channel 37 (608-614 MHz) has been set aside for radio astronomy and other scientific measurements and research. Will repacking change interference into Channel 37? Is the FCC still considering moving this radio astronomy function to a different channel?

Rhodes: The FCC would face many difficulties in any re-allocation of Channel 37. Although the number of radio astronomy sites is small, there are some 2,700 hospitals with wireless telemetry operating on Channel 37. These wireless telemetry applications involve patient monitoring, which requires the highest possible standards of reliability. Any significant increase in TV stations on Channel 36 or 38 or any use of those frequencies by cellular providers could result in patients dying.

I am sure the FCC will not re-allocate Channel 37, but I am concerned with the possibility of sharing that vital channel with unlicensed transmitters. That must not be permitted.

BE Extra: Is there anything that broadcasters can do today to get maximum coverage and minimize interference with other broadcasters?

Rhodes: Maximizing coverage while minimizing interference are mutually contradictory objectives. Could DTV receivers be designed to be more robust to interference within the present state-of-the art? Probably they could, but at what cost? The question today is moot in my opinion, as the public has well more than 100 million ATSC receivers. My own laboratory has about 22 modern receivers and 25 NTIA-approved converter boxes, and these receivers can and do provide excellent reception now. However, will they provide it after repacking with the resulting spectrum congestion?

BE Extra: Is there anything else we should know regarding DTV interference and TV spectrum repacking?

Rhodes: Broadcasters should be aware that interference is minimized by co-siting of stations that otherwise can, because of their assigned channels, cause interference. This applies to interference between stations not on the same channel. Unfortunately, co-siting of DTV towers and cellphone towe
LINK: http://www.tvtechnology.com/news/0110/dtv-interference-repacking-and-t...
See more stories from tvtechnology

Most recent headlines

05/01/2027

Worlds first 802.15.4ab-UWB chip verified by Calterah and Rohde & Schwarz to be demoed at CES 2026

Worlds first 802.15.4ab-UWB chip verified by Calterah and Rohde & Schwarz to be ...

04/08/2026

Dalet Announces Commercial Availability of Dalia, Bringing Media-Aware Agentic AI to Enterprise Productions

Dalet, a leading technology and service provider for media-rich organizations, t...

04/07/2026

Detective Conan: Fallen Angel of the Highway Opens in Dolby Cinemas Across Japan, Presented in Dolby Atmos and Dolby ...

April 7 2026, 19:00 (PDT) Detective Conan: Fallen Angel of the Highway Opens in...

01/06/2026

Dolby Sets the New Standard for Premium Entertainment at CES 2026

January 6 2026, 05:30 (PST) Dolby Sets the New Standard for Premium Entertainment at CES 2026 Throughout the week, Dolby brings to life the latest innovatio...

13/05/2026

New Adobe Premiere Color Grading Mode Accelerated on NVIDIA GPUs

New Adobe Premiere Color Grading Mode Accelerated on NVIDIA GPUs Joel Pennington May 13, 2026 0 Comments New NVIDIA RTX-accelerated features streamlin...

13/05/2026

dB Broadcast Delivers New IP-based Cloudbass Sports OB Tr...

Grass Valley announced that dB Broadcast has delivered new IP-based outside broadcast (OB) trucks for Cloudbass, featuring Grass Valley LDX 100 Series cameras a...

13/05/2026

Ikegami Announces its Broadcast Asia 2026 Innovations

Ikegami will exhibit the latest additions to its wide range of broadcast production cameras, control units, viewfinders and monitors on stand 5D3-1 at Broadcast...

13/05/2026

XRSA and FISE Partner to Deliver Immersive Action Sports...

FISE, working with the founding members of the XR Sports Alliance (XRSA), Accedo, Qualcomm Technologies, Inc. and HBS, have collaborated to develop an immersive...

13/05/2026

Canon Unveils New EOS R6 V Full-Frame EOS Camera and RF20-50mm F4 L IS USM PZ Built-In Power Zoom Lens

Canon Unveils New EOS R6 V Full-Frame EOS Camera and RF20-50mm F4 L IS USM PZ Bu...

13/05/2026

Boston Conservatory at Berklee Honors Beth Morrison and Moses Pendleton at Commencement Ceremony

Boston Conservatory at Berklee Honors Beth Morrison and Moses Pendleton at Comme...

13/05/2026

CBS Boston to Air CCBL Baseball

Share Copy link Facebook X Linkedin Bluesky Email...

13/05/2026

Study: Free Streaming Emerges as TV's New Normal

Share Copy link Facebook X Linkedin Bluesky Email...

13/05/2026

Amagi Announces Major Enhancements To CLOUDPORT

Share Copy link Facebook X Linkedin Bluesky Email...

13/05/2026

FCC Releases Updates to TVStudy Software

Share Copy link Facebook X Linkedin Bluesky Email...

13/05/2026

Nexstar Names Elizabeth Ryder EVP, General Counsel

Share Copy link Facebook X Linkedin Bluesky Email...

13/05/2026

Foundry releases Nuke Stage- simplifying virtual producti...

Creative software developer Foundry today announced the latest developments on Nuke Stage. A purpose-built application for end-to-end virtual production and in-...

13/05/2026

Tradfluencer - The Sharon Shannon Story

A definitive portrait of one of Ireland's most influential musicians New TV documentary airs Monday 18 May on RT One and RT Player at 9.35pm Watch the...

13/05/2026

Hermes Unlocks Self-Improving AI Agents, Powered by NVIDIA RTX PCs and DGX Spark

Agentic AI is changing the way users get work done. Following the success of OpenClaw, the community is embracing new open source agentic frameworks. The latest...

13/05/2026

NVIDIA, Ineffable Intelligence Team Up to Build the Future of Reinforcement Learning Infrastructure

Reinforcement-learning agents - AI systems that learn by trial and error - can c...

12/05/2026

Beyond the Hype: A Strategic Post-Hoc Analysis of NAB 2026

Beyond the Hype: A Strategic Post-Hoc Analysis of NAB 2026 If NAB Show 2026 had an underlying theme, it was a quiet, industry-wide pivot from the high-energy sp...

12/05/2026

G&D and CT Square Establish Joint Venture for India and Middle East Distribution

Guntermann and Drunck (G&D), a Panoptec Technologies Group company, and CT Square, led by Chandresh Shah, have announced a joint venture to distribute G&D and V...

12/05/2026

Telemundo Reports Record Advertiser Demand for FIFA World Cup 2026 Coverage

With 30 days until the start of the FIFA World Cup 2026, Telemundo, the exclusive Spanish-language home of the tournament in the United States, has announced th...

12/05/2026

NHLs Stanley Pup Returns for Third Year on June 8

The NHL has announced the return of Stanley Pup for its third consecutive year, a 90-minute special featuring adoptable rescue dogs competing on a miniature rin...

12/05/2026

NBCUniversal Outlines Ad Technology and Content Strategy at 2026 Upfront

NBCUniversal presented its 2026 Upfront to advertisers at Radio City Music Hall, detailing upcoming programming across NBC, Peacock, Bravo, and Versant properti...

12/05/2026

FOX Sports Funds Fandom Research Initiative at Harvard Kennedy School

FOX Sports has announced funding for the Fandom and Social Connection Initiative at Harvard Kennedy School's Shorenstein Center on Media, Politics, and Publ...

12/05/2026

TNDV and Live Media Support NCAA Final Four Weekend for 13th Consecutive Year

TNDV and Live Media, both divisions of Live Media Group, supported live broadcast coverage around NCAA Final Four weekend in Indianapolis, including the March M...

12/05/2026

European Football Alliance Signs Distribution Agreement with Fubo Sports Network

The European Football Alliance (EFA) has announced a content distribution agreement with Fubo Sports Network, the free ad-supported streaming TV (FAST) channel ...

12/05/2026

ESPN, TelevisaUnivision Ink Deal to Produce Additional Spanish-Language Super Bowl LXI Telecast

For the first time, Spanish-speaking fans in the U.S. will have two separate tel...

12/05/2026

CP Communications Manages RF Spectrum for Kentucky Derby Week

CP Communications led a comprehensive spectrum management initiative on behalf of Churchill Downs during Kentucky Derby week, coordinating RF assets across the ...

12/05/2026

LiveU and DRONERESPONDERS Announce Partnership for Public Safety Drone Video Transmission

LiveU has announced a strategic partnership with DRONERESPONDERS, a 501(c)3 non-...

12/05/2026

BMC TV Selects Open Broadcast Systems 5G Flyaway for Horse Racing Transmissions

Open Broadcast Systems has announced that BMC TV, a specialist in IP transport of broadcast content, has selected the Open Broadcast Systems 5G Flyaway solution...

12/05/2026

NEP Europe to Deliver Broadcast Solutions for Eurovision Song Contest 2026 in Vienna

NEP Europe, part of NEP Group, has announced it will deliver broadcast solutions...

12/05/2026

Grass Valley Expands Collaboration with Ravensbourne University London on Media Production Education

Grass Valley has announced continued collaboration with Ravensbourne University ...

12/05/2026

Stats Perform Launches Opta Pulse AI-Assisted Video Creation Platform

Stats Perform has announced the launch of Opta Pulse, an AI-assisted video creation and distribution platform for leagues, rights holders, and broadcasters. The...

12/05/2026

FOX Sports and Sesame Workshop Announce Collaboration for FIFA World Cup 2026

FOX Sports has announced a collaboration with Sesame Workshop to integrate Sesame Street characters into FOX Sports' FIFA World Cup 2026 programming. Conten...

12/05/2026

Little Show, Giant Heart: NHL in ASL Earns Two Sports Emmy Nominations in 2026

To date, NHL Productions has produced 19 broadcasts with commentary in American Sign Language NHL in ASL (American Sign Language) may be just one show, but the...

12/05/2026

At Its Annual Brandcast, YouTube Aims To Show Why Sports Is No Longer Just the Game

Google's Brian Albert: creators, athletes, highlights, nostalgia, second-scr...

12/05/2026

Your Next Double Feature: Old Joy and Past Lives

A still from Past Lives by Celine Song, an official selection of the Premieres program at the 2023 Sundance Film Festival. (Courtesy of Sundance Institute | p...

12/05/2026

It's Your Party of the Year(s): A Look Back at Your Entire Music History on Spotify

Spotify is where fans and artists come together, turning discovery into somethin...

12/05/2026

Black Lion Audio introduce the Auteur 8DAT

Features patented Marco-MMC clocking technology Black Lion Audio's latest release combines the company's expertise in clocking with their renowned p...

12/05/2026

Reason 14 now available

New Track Panel, sequencer upgrades & more Following their recent public beta release, Reason Studios have announced the full release of Reason 14. With the...

12/05/2026

One month to go! SBS reveals expansive FIFA World Cup 2026 lineup beyond the pitch

One month to go! SBS reveals expansive FIFA World Cup 2026 lineup beyond the pi...

12/05/2026

Rohde & Schwarz presents its advanced solutions for power electronics testing at PCIM Expo 2026

Rohde & Schwarz presents its advanced solutions for power electronics testing at...

12/05/2026

Ad-Hoc News: aconnic AG announces improved fund raising plan to support business and refinance debt

aconnic AG (ISIN: DE000A0LBKW6), Munich, has developed a modified fund raising p...

12/05/2026

CNN Pushes Into Lifestyle Products with CNN Weather' App Launch

Share Copy link Facebook X Linkedin Bluesky Email...

12/05/2026

Marshall Electronics Cameras Elevate Elite Equestrian Com...

Tyrell Corporation, specialists in high-end live sports and entertainment broadcasts, was tasked with delivering compelling broadcast coverage of premier equest...

12/05/2026

IBC2026 registration opens as international media industr...

Registration is now open for IBC2026 as the global media, entertainment and technology community prepares to converge on the RAI Amsterdam from 11 14 September ...

12/05/2026

Ross Video Showcases Unified Production Workflows at Broa...

Ross Video, a global leader in live video production technology, will present its latest innovations and integrated production workflows at BroadcastAsia 2026, ...

12/05/2026

With over 50bn euros in assets under management and recor...

500 selected leaders from around the world across start-ups, corporates, and venture capital. Over 50bn in assets under management among attending investors, a...