My colleague Linley Gumm and I recently conducted a series of measurements of the threshold protection (desired/undesired (D/U)) ratios required for modern ATSC receivers to reject interference from LTE signals radiated by base stations in the 600 MHz Band. We tested 21 receivers and forwarded our results to the International Telecommunications Union through Dr. Charles Einolf, a U.S. member of the ITU working group dealing with such interference issues. Our paper described how we conducted these tests and our results. This report is available from the ITU website www.itu.int/pub/R-REP-BR.2215-6-2016, entitled Measurement of Protection Ratios and Overload Threshold for Broadcast TV Receivers. Our contribution is Annex 3F.
THE PROBLEM
Our problem was to find a source of real, live LTE signals for testing purposes. We found two such LTE signals on-the-air in the 700 MHz band with strong signals, each 10 MHz wide centered at 739 MHz and 751 MHz. These we heterodyned down into the 600 MHz band. Such signals in the 600 MHz band would consist of two 5 MHz blocks of contiguous frequencies, so we were emulating what we believe will be common practice in the 600 MHz band after the 600 MHz band is repacked following the spectrum auctions.
By now, it is generally accepted that ATSC reception may be jammed by pairs of undesired signals on Channels N K and N 2K with the desired signal on Channel N or N 3 if third-order intermodulation (IM3) products are being generated in the frontend of the affected receivers.
Gumm proposed to heterodyne our LTE signals into Channels 18 MHz above and below the desired ATSC signal on Channel N. None of the third-order distortion products fall within the desired Channel N. The desired ATSC signal was being jammed. That is what we reported in Table 3 on page 8 of what today is Annex 3F to the ITU Report BT-2215. This data is given in the column marked No IM3. Without any IM3 in desired Channel N, we found that the threshold D/U ratio was, for 90 percent of the receivers, to perform -32 dB. Two LTE signals 18 MHz above and below the desired ATSC signal power cannot be more than 32 dB greater than the ATSC signal power. That is a long way from the -60 dB D/U threshold, which the FCC assumes for planning purposes. When our two LTE signals were centered on Channels N K and N 2K, the undesired threshold was -28 dB, only 4 dB worse. This is shown for FCC Scenarios 7, 10 and 12 in the abovementioned table in Annex 3F. Even with a perfectly linear receiver front-end (which would not generate IM3), interference was only slightly reduced.
What could explain why we saw interference, which could not have been generated in the receiver? Well, we saw desensitization. All modern DTV receivers have wideband RF automatic gain control (AGC). Strong undesired signals on Channels N /-3 forced the wideband RF AGC system to reduce the gain of the RF amplifier to protect the mixer from being overloaded. Table 1 summarizes our test results for the 21 modern ATSC receivers detailed in Annex 3F of the ITU Report.
Table 1: Threshold D/U (dB) for 21 modern ATSC Receivers from LTE signals
Most recent headlines
05/01/2027
Worlds first 802.15.4ab-UWB chip verified by Calterah and Rohde & Schwarz to be ...
04/08/2026
Dalet, a leading technology and service provider for media-rich organizations, t...
04/07/2026
April 7 2026, 19:00 (PDT) Detective Conan: Fallen Angel of the Highway Opens in...
01/06/2026
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...
30/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
30/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
30/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
30/05/2026
Zero in on one that says yes (and no)
Andy Marken May 29, 2026
0 Comments
Hero image courtesy of Deposit Photos
For content creators the most difficu...
29/05/2026
With InfoComm 2026 just weeks away, NDI is giving attendees plenty of reasons to...
29/05/2026
Reaffirming a partnership that has defined Canadian sports broadcasting since 19...
29/05/2026
Mobile/tablet is No. 2 device for watching TV, suggesting that the sports-production industry needs to take another look at the format
Ring Digital's Sprin...
29/05/2026
Berliner Ensemble, one of Berlin's five major theater companies, has expande...
29/05/2026
Solid State Logic will showcase its new compact, fly-away TCA Tour audio product...
29/05/2026
Gerald (Jerry) Pierce, a pioneering technologist who helped shape the digital transformation of the motion picture industry, passed away last month on April 12 ...
29/05/2026
Paramount+ will be the English-language U.S. home for Barclays Women's Super...
29/05/2026
Further strengthening its virtualisation strategy to fully support broadcasters ...
29/05/2026
Swiss broadcaster Canal Alpha has deployed Harmonic's award-winning, software-based XOS Advanced Media Processor to modernize playout operations across cant...
29/05/2026
PTZOptics will showcase a new generation of intelligent video workflows at InfoComm 2026, June 17-19, Las Vegas. Visitors to booth N8227 will see how PTZOptics ...
29/05/2026
Arizona's Family has launched the Arizona's Family Sports (AZFS) streaming app, a new direct-to-consumer destination for live, local sports. The app is ...
29/05/2026
Starting in 2027, DAZN will be the exclusive home of The Canadian Football Leagu...
29/05/2026
Comcast Business has detailed the advanced network infrastructure it has deploye...
29/05/2026
In two-day event, leaders from academia and industry explored solutions to chall...
29/05/2026
The Basketball Tournament (TBT), now entering their 13th year of competition, ha...
29/05/2026
Roku has launched FOX One as a Premium Subscription on The Roku Channel in the U.S. Roku customers can now subscribe to FOX One using their Roku account for liv...
29/05/2026
In its sixth year, the broadcaster's coverage has become a global brand and ...
29/05/2026
Ratings Roundup is a rundown of recent ratings news and is derived from press re...
29/05/2026
The days are getting longer, the temperatures are rising, and playlists are filling up for the season. With summer around the corner, Spotify's global edito...
29/05/2026
New retro-inspired MPC announced
There are few devices that have gained the status held by Akai Pro's MPC range, and in recent years, the company have s...
29/05/2026
Save up to 30 on acclaimed titles
Following a successful launch at Superbooth 2026, Bjooks have revealed that they will be continuing the Kickstarter campa...
29/05/2026
Binaural monitoring application improved
Genelec have just released an update that brings some powerful new features to their HRTF-based binaural headphone ...
29/05/2026
6 June 2026 at SAE Institute, London, UK
IMSTA FESTA 2026 is almost upon us, with some of the biggest names in pro-audio set to descend upon SAE Institute i...
29/05/2026
Gerald (Jerry) Pierce, a pioneering technologist who helped shape the digital transformation of the motion picture industry, died April 12, 2026, at his home in...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Comparing 5 AI Video Enhancers for Restoring Old Video Quality
Kate Luvis May 29, 2026
0 Comments
Digitizing VHS, MiniDV, and other legacy formats doe...
29/05/2026
Studio Hamburg Builds New Post Pipeline with DaVinci Resolve Studio
Brie Clayton May 29, 2026
0 Comments
Workflow replaces a patchwork of legacy tools...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
Share
Copy link
Facebook
X
Linkedin
Bluesky
Email...
29/05/2026
At the Intersection of Music and Dance, an Epic Collaboration Boston Conservatory musicians and dancers found creative parallels in their recent performance o...
29/05/2026
Back to All News
Latino Film Institute Fellows Screen Their Short Films at the Egyptian Theatre
The Inclusion Fellowship and Spark Animation Grant uplifts 15 ...
29/05/2026
GLOOKAST LAUNCHES CINNAFILM TACHYON PLUGIN FOR MEDIA PRODUCER AND MEDIA SERVICES
This release first appeared here.
Visit our Tachyon product page or contact...
29/05/2026
May 29 2026, 09:00 (PDT) Dolby and rednote Bring More Immersive Storytelling to...
29/05/2026
Something fundamental has shifted in how people consume media. Audiences aren't abandoning television or radio content; they're just expanding how, wher...
29/05/2026
Youtube exclusive special drops today
Watch now
UKTV today announces another e...
29/05/2026
Back to All News
The Official Trailer of Physical 100 Italy, on Netflix From Se...
My colleague Linley Gumm and I recently conducted a series of measurements of the threshold protection (desired/undesired (D/U)) ratios required for modern ATSC receivers to reject interference from LTE signals radiated by base stations in the 600 MHz Band. We tested 21 receivers and forwarded our results to the International Telecommunications Union through Dr. Charles Einolf, a U.S. member of the ITU working group dealing with such interference issues. Our paper described how we conducted these tests and our results. This report is available from the ITU website www.itu.int/pub/R-REP-BR.2215-6-2016, entitled Measurement of Protection Ratios and Overload Threshold for Broadcast TV Receivers. Our contribution is Annex 3F.
