SAN JOSE, Calif.—DTS, Inc. a subsidiary of Xperi, has announced “DTS Clear Dialogue,” a new on-device solution that leverages the latest advancements in AI-based audio processing to improve dialogue intelligibility for TV audio.

DTS Clear Dialogue addresses one of the biggest audio complaints from consumers—not being able to clearly understand spoken onscreen dialogue. There are many reasons why consumers have difficulty understanding onscreen dialogue: device limitations, inconsistent audio across content sources, environmental noise or individual hearing abilities.

Xperi says its DTS Clear Dialogue provides consumers with the ability to personalize and optimize their audio experience, significantly improving their understanding of dialogue.

“Sound quality is an essential part of the TV and video viewing experience," says Greg Ireland, senior research director at IDC. "IDC's consumer survey results continue to show that sound quality is highly important to a strong majority of viewers. Moreover, sound quality applies to older and young consumers, signaling that solutions that enable improved audio experiences address a highly important facet of the viewing experience for consumers across all generations.”

A recent Xperi survey of 1,200 U.S. adults revealed that 84% of consumers have experienced trouble understanding dialogue during TV shows and movies. In response, over three-quarters (77%) of survey respondents said they use captions/subtitles, with one in three (30%) reporting they are always or often turned on.

“When viewers can’t hear the dialogue, it degrades the quality of their TV experience and turning on subtitles is a workaround, not a solution,” says Geir Skaaden, chief products & services officer at Xperi. “To date, attempts to mitigate audio post-processing limitations don’t address the complex underlying problems across languages, content and environment, and can’t account for each viewer’s individuality. Our device-side AI-based audio processing solution will allow TV OEMs to provide their viewers with the ability to customize and personalize their audio experience.”

DTS Clear Dialogue leverages AI audio processing innovation and machine learning techniques to identify, separate and enhance dialogue so listeners can better understand it. Clear Dialogue is language-inclusive and agnostic to content type (movies, TV shows, sports, live events, etc.).

Xperi says that according to its own survey, 79% of U.S. consumers said that DTS Clear Dialogue would increase their interest in a smart TV that offered it. Top use cases include when: actors do not speak clearly (40%), non-dialogue audio elements are too loud (38%), viewers want to watch at a lower overall volume to avoid disturbing others (35%) and the TV-watching environment is too noisy (34%).

Xperi says DTS Clear Dialogue for TV OEMs can identify and separate virtually any element within an audio program to optimize its performance, distinguishing between elements such as dialogue, music and special effects. Users can also create personalized profiles with dialogue and non-dialogue settings, to address hearing impairment, listening environments and audio preferences for varying conditions.

“This new level of AI-powered personalization addresses listener needs and can compensate for individual hearing impairment, device limitations and listening environments for the first time,” continues Skaaden. “Providing this deeper level of understanding and enjoyment of TV content benefits everyone, from the viewers themselves to advertisers, streaming services, movie and TV studios and TV OEMs.

Xperi will demo DTS Clear Dialogue at stand in Hall 22-306, during IFA in Berlin, Sept. 6-10.

WASHINGTON, D.C.—In a development that has important implications for the ongoing rollout and success of data services and NextGen TV, the FCC has closed its reconsideration of a 2021 ruling on distributed television systems. 

Microsoft had requested that the FCC reconsider the DTS Report and Order that modified the Commission’s technical rules. The modifications were designed to promote expanded use of distributed transmission systems (DTS) by broadcast television stations. The NAB and broadcasters had requested the changes to help broadcasters speed up the deployment of NextGen TV services and the development of data services. 

Microsoft filed a petition in March of 2021 asking the FCC to reconsider that decision because the order would hurt their Airband Initiative to use TV white spaces to provide broadband services in rural areas. It "needlessly worsens an already-difficult environment" for TV white spaces deployments, the filing noted. 

The NAB responded with a May 25, 2021 blog post by NAB deputy general counsel Patrick McFadden blasting Microsoft's efforts to get the FCC to revise the January 2021 ruling, calling Microsoft's Airband Initiative "hot air" and a heavily hyped solution to the rural broadband gap that has not lived up to its promises.

Later in a August 3 filing with the FCC, APTS and the NAB continued their opposition to Microsoft, arguing that “Microsoft’s petition presents no legitimate case for reconsideration and the Commission should promptly deny it.”

On August 5, 2024, the FCC reported that “Microsoft filed a request for withdrawal of the Petition stating that it is `no longer pursuing or advocating for the matters raised in the Petition’ and that the Petition may be dismissed.”

In response, the FCC ordered that “the request for withdrawal filed by Microsoft Corporation IS GRANTED, and the petition for reconsideration filed by Microsoft Corporation IS DISMISSED without prejudice. IT IS FURTHER ORDERED that, should no petitions for reconsideration or petitions for judicial review be timely filed, MB Docket No. 20-74 SHALL BE TERMINATED and its docket closed.”

BURBANK, Calif. and NEW YORK—Disney+, IMAX Corporation, and DTS, a wholly-owned subsidiary of Xperi, have announced that “Queen Rock Montreal” is now streaming on Disney+.

The May 15 debut is notable in that it is the first concert film to be streamed with IMAX Enhanced sound powered by DTS, the companies said. 

The companies also reported that along with the “Queen Rock Montreal” film, Disney+ subscribers got access on May 15 to 18 Marvel films with IMAX Enhanced sound. 

The streaming debut of “Queen Rock Montreal” means that subscribers using IMAX Enhanced certified devices will be able to feel the full dynamic range of every heart-pounding moment of the digitally remastered concert film, which presents Freddie Mercury, Brian May, Roger Taylor and John Deacon in the original concerts. 

The film was restored for IMAX by Mercury Studios. Executive producers include Geoff Kempin and Alice Webb for Mercury Studios and Jim Beach and Matilda Beach for Queen Films.

In addition to the concert film, select Marvel Studios films became available with IMAX Enhanced sound on Disney+ on May 15, including: 

• Ant-Man and the Wasp
• Doctor Strange
• Ant-Man and the Wasp: Quantumania
• Doctor Strange in the Multiverse of Madness
• Avengers: Infinity War
• Eternals
• Avengers: Endgame
• Guardians of the Galaxy (Vol. 2)
• Black Panther
• Guardians of the Galaxy (Vol. 3)
• Black Panther: Wakanda Forever
• The Marvels
• Black Widow
• Shang-Chi and the Legend of the Ten Rings
• Captain America: Civil War
• Thor: Ragnarok
• Captain Marvel
• Thor: Love & Thunder

Disney+ is the first major streaming service to elevate the at-home viewing experience with IMAX Enhanced, giving its subscribers new ways to re-experience the Marvel Cinematic Universe and beyond, IMAX reported. 

WASHINGTON—Broadcasters potentially stand to gain millions of NextGen TV over-the-air viewers thanks to FCC rule changes and clarifications released Jan. 19 that expand the permissible range of signal spillover from DTS (distributed transmission system) transmitters.

The impact of the rule changes will be significant when it comes to the number of people and devices able to receive ATSC 3.0 signals and services, said Erik Langner, president of Public Media Group (PMG), a NextGen TV infrastructure company that will partner with broadcasters to operate ATSC 3.0 facilities.

Estimated population gains for broadcasters in five markets illustrate what the rule change may mean. Comparing big stick transmission to a DTS NextGen TV network received by devices indoor at a height of 1.5 meters, PMG estimates OTA population gains of 4.3 million in Los Angeles; 3 million in Boston; 2.7 million in Miami; 2.5 million in Dallas; and 1.5 million Detroit.

“We have worked with multiple public and commercial broadcasters in various markets to design single frequency networks, and the impact is significant in terms of the number of people and devices that will receive ATSC 3.0 signals and service,” he said.

The 1.5-meter height was selected because consumers are more likely to use an indoor antenna or watch on mobile devices than mount a rooftop antenna at 10 meters, he added.

The new rules remove nebulous language that described permissible spillover beyond a station’s authorized service area as a “minimal amount” and replace it with precise language. 

For UHF stations, the rules now mandate the 41 dBu F(50,50) contour for each DTS transmitter in use not exceed the reference station’s 41 dBu F(50,50) contour. The corresponding values for low VHF are now 28 dBu and for high VHF 36 dBu.

Langner isn’t alone in the upbeat assessment of the rule change. Both America’s Public Television Stations and NAB, which asked the FCC to make the rule change, lauded the action.

“America’s Public Television Stations applaud the action taken today by the FCC, a welcome endorsement of changes in the current rules that will allow broadcast television stations to unlock the benefits of NextGen TV through DTS operations that better serve their viewers and preserving their commitment to localism,” said Lonna Thompson, executive vice president, chief operating officer and general counsel of APTS. 

The FCC Report and Order, released Jan. 19 and adopted Jan. 13, follows a petition for rulemaking submitted by APTS and NAB, which prompted the agency to release a Notice of Proposed Rulemaking leading to the changes.

“NAB applauds the Commission for adopting rules that will allow broadcasters to offer improved service to viewers,” said Ann Marie Cumming, senior vice president, Communications, at NAB. “The balanced approach taken by the order represents a fair compromise that will provide greater certainty to stations seeking to deploy NextGen TV. We particularly appreciate the hard work of the Commission staff in this technical proceeding.”

Pearl TV, which last fall began SFN testing in Phoenix as part of the model market project, welcomed the news.

“We're pleased that the Commission adopted this change to the rules on Single Frequency Networks [a synonym for DTS networks], since it will help broadcasters roll out NextGen TV more quickly and more efficiently,” said Pearl TV Managing Director Anne Schelle. 

The rule changes will enable ATSC 3.0 to fulfill its potential, said Jerald Fritz, executive vice president at ONE Media 3.0.

“The promise of 3.0 is the ability to provide robust services—video and data—to all parts of licensed service areas,” he said. “SFNs will enhance that enterprise, and the new DTS rules will enable those new service nodes. So, we are pleased the Commission allows us to enhance our services to more parts of our licensed service areas.”

Merrill Weiss, DTS pioneer and owner of Merrill Weiss Group, sees the rule changes as a positive development.

“The DTS Report and Order goes a long way toward overcoming the most serious limitation that has held back DTS implementation over the dozen years that DTS has been in the FCC’s rules. It will enable providing higher and more uniform signal levels throughout stations’ service areas,” he said.

“It will allow designs of DTS networks to be created with knowledge on the parts of their designers that their designs will be acceptable for authorization. It also will expand the use of DTS to more types of digital stations on a routine basis, now including Class A and Low Power stations in addition to full-power stations.”

WASHINGTON—The FCC released an update to its DTS (distributed transmission system) coverage rules to expand the permissible range of signal spillover and replace the subjective “minimal amount” language used to describe spillovers as a way to promote ATSC 3.0 reaching its full potential.

The change gives broadcasters more flexibility in placement of DTS transmitters. For UHF stations, the rule change mandates that the 41 dBu F(50,50) contour for each DTS transmitter in use does not exceed the reference station’s 41 dBu F(50,50) contour. The corresponding values for low VHF are now 28 dBu and for high VHF 36 dBu.

The Report and Order, adopted Jan. 13, explained that the agency’s actions are intended to afford “broadcasters greater flexibility in the placement of DTS transmitters …” that will “allow them to enhance signal capabilities and fill coverage gaps, improve indoor and mobile reception, and increase spectrum efficiency by reducing the need for television translator stations operating on separate channels.”

The change gives no protection to DTS transmissions beyond a station’s authorized service area. It also removes the requirement for Class A, LPTV and TV translator stations to apply for DTS facilities on an experimental basis. The new DTS contour-based limit for these broadcasters is similar to the change adopted for full-power broadcasters but is “modified slightly to account for technical differences …,” it said.

“[O]ur adopted approach will allow broadcasters to improve coverage in their service areas, without causing more spillover than necessary to promote DTS deployment,” the R&O said.

While the change increases the permitted area for DTS spillover, it does not change a station’s area of interference protection, the R&O said.  “Specifically, such spillover will be subject to a bright-line limitation …”

By relaxing and clarifying how much DTS spillover is allowed at the fringe of a full-power station’s coverage contour, stations will be permitted to deliver a stronger signal to viewers located at the edges of their service areas and where terrain hampers delivery, it said.

The R&O was prompted by a petition for rulemaking filed by America’s Public Television Stations (APTS) and NAB. The FCC issued a Notice of Proposed Rulemaking seeking comment.  

FCC Chairman Ajit Pai and Commissioner Brendan Carr supported the rule change. Commissioners Jessica Rosenworcel and Geoffrey Stark approved in part and dissented in part. 

More information is available on the FCC website. 

WASHINGTON—A number of organizations have come out against the FCC proposal to expand broadcasters' use of distributed transmission systems.

While computer companies like Microsoft have long been against the expansion of DTS because it could reduce the amount of their broadcast "white spaces" spectrum, other organizations like the National Veteran Small Business Coalition, National Rural Education Association and Citizens Against Government Waste have filed comments with the FCC against the commission taking such action.

Broadcast organizations, like NAB, have pushed the FCC to support DTS expansion, as they believe it will help expand their ATSC 3.0 footprints and finalized deployment plans.

For more information on the DTS proposal, visit TVT's sister publication B+C.

WASHINGTON—A day after the APTS and NAB offered their comments requesting the expansion of Distributed Transmission Systems, tech groups—specifically New America’s Open Technology Institute and Public Knowledge—are making their case as to why DTS spillover signals at this time should be considered unlicensed.

The FCC Notice of Proposed Rulemaking that has resulted in these comments is proposing an expansion of the commission’s rules regarding DTS. However, OTI and PK are supporters of TV white spaces, the spectrum between TV stations and wireless broadband. The expansion of DTS would decrease the spectrum available for wireless broadband, they argue.

In the joint APTS, NAB comments, they say that expansion of DTS will help with the deployment of the ATSC 3.0 standard. OTI and PK counter by saying it is premature to take such action on that since there are few ATSC 3.0 services available to the public and the benefits aren’t yet known.

“At this early stage in the development of ATSC 3.0, the commission should not rely on promises of future services as the basis for another massive giveaway of spectrum to broadcasters,” the comments read.

Other potential issues with the current proposal is the possible creation of a DTS “Interference Area” more than twice the size of the current licensed coverage area of a broadcast station licensee, the tech groups claim. To help against this, the two organizations urge the FCC to not grant signal interference protection.

“Upgrading the status of spillover signals beyond DTS station’s areas to primary or secondary status could effectively grant broadcast licensees twice as much spectrum without even requiring that the license use the free spectrum to deploy services promised when ATSC 3.0 was authorized,” OTI and PK write.

Granting interference protection could also deny neighboring communities of other services, including TV white spaces, which could deter the use of vacant TV band spectrum to help try to close the rural connectivity divide, per the comments.

“DTS spillover signals should be considered unlicensed and should not confer interference protection rights against other licensed or unlicensed operations,” OTI and PK conclude.

The full comments are available through the FCC’s ECFS. 

WASHINGTON—America’s Public Television Stations (APTS) and the NAB are calling on the FCC to allow them greater use of Distributed Transmission Systems, while subsequently arguing that any proposal creating rights for unlicensed and secondary services to use DTS should be rejected.

These stances come from comments filed jointly by APTS and NAB regarding a Notice of Proposed Rulemaking by the FCC on changing its rules governing DTS.

APTS and NAB state that initial comments to this NPRM are supportive of the amendment that would have the FCC permit greater use of DTS. They say there are public interest benefits to amending the rules that would enable broadcasters to provide superior coverage, including at the edge of stations’ service areas. It is also argued that such amendments should be done as quickly as possible as it could have an impact on deployment plans for stations transitioning to ATSC 3.0, the NextGen TV standard.

“Swift approval of the requested changes will improve service to viewers, encourage investment and speed the rollout of ATSC 3.0 services,” the comments read. “We urge the commission to move forward quickly with an order amending the existing DTS rules.”

The two groups acknowledge what they call the “sole opposition” to the DTS proposal, advocates for unlicensed and secondary services who are asking for the FCC to provide them with new spectrum rights. However, the National Translator Association has also shared its opposition to new DTS rules to the FCC via filed comments.

Specifically in its comments though, APTS and NAB name Microsoft, New America’s Open Technology Institute and Public Knowledge that are pushing against changes to DTS rules because of the potential for such changes to diminish opportunities for the use of TV white space technology to close the rural broadband gap.

“These arguments are inconsistent with commission rules and precedent and lack any sound basis in public policy,” the comments read. “The commission should reject the invitation to use this proceeding to create unprecedented and legally unsustainable rights for unlicensed and secondary services.”

In fact, APTS and NAB make the case that expanded DTS operations could result in more opportunities for white spaces as it would help reduce dependence on TV translators operating on different channels to reach difficult service areas.

“Broadcasters have proposed very targeted changes to the existing DTS rules that will allow them to realize substantial public interest benefits associated with DTS deployments,” the comments conclude. “The only opposition to this proposal comes from parties with secondary or non-existent spectrum rights that ask the commission to provide them with unprecedented and unwarranted protections that will have the effect of constraining innovation. The commission should reject these requests and allow broadcasters to provide better service to viewers through more robust in-home and mobile coverage and enhanced spectrum efficiency.”

The full comments are available on the FCC’s ECFS. 

WASHINGTON—The National Translator Association has come out against the recent FCC proposal to expand Distributed Transmission Systems (DTS), saying that it would cause significant interference to hundreds of stations.

The NTA comments were filed on June 12 in response to the FCC’s Notice of Proposed Rulemaking that would allow for new and expanded uses of DTS. A number of organizations, including the NAB and APTS, have supported the NPRM, saying that it would help with the deployment of ATSC 3.0 and enhance “localism,” particularly in more remote areas.

NTA, however, believes that translators and low power TV stations are already qualified to handle these tasks.

“Translators and LPTV stations already cover Rural America, so it is easy for us to just add a station to deliver “Next Gen” signals, providing the coverage contours are adjusted to meet needs and that no interference is generated from full power DTS stations seeking to ‘bend’ beyond their contour impacting Class A, translator and LPTV stations,” said John Terrill, NTA president.

NTA says that proponents of DTS have acknowledged that interference would be a result of the move and that it would be “dramatic” and “unavoidable” for the development of next-gen television.

NTA countered with three key points:

• NTA cannot think of any justification for one station interfering with another outside of its service contour, especially if it is importing programming intended for markets over 121 kilometers distant. 
• The impact signals would most likely be a competitor’s signal. 
• The proposal is not clear as to where the standards bend. If it is in a crowded major market such as Los Angeles, Denver or Salt Lake City, where terrain plays a major part in coverage, the impact on the public living in the mountains can be significant. 

An alternative proposed by the NTA is that a DTS station file with the FCC for a next-gen very lower power translator or another open frequency, “with injury toward none.”

In addition, NTA proposes a new filing window for a “Next Gen” station to be added to the market, what it calls an easy and low cost fix using present transmission sites, providing more rural internet service and fix remaining repack problems.

The complete comments can be found on the FCC’s ECFS. 

WASHINGTON—America’s Public Television Stations and the NAB are happy with the actions so far by the FCC when it comes to potential changes to rules regarding Distributed Transmission Systems (DTS) and the deployment of ATSC 3.0, and wants the commission to keep the momentum going.

Comments jointly filed by the APTS and NAB last week regarding a Notice of Proposed Rulemaking on changes to DTS see the two organizations praising the FCC’s expeditious movement on the issue and hope to continue to do so as they believe rules that allow for the greater use of DTS systems will provide superior coverage, particularly at the edges of stations’ service areas, while also enhancing the principle of localism.

“As stations plan to transition to ATSC 3.0 in the coming months and years, each station’s specific deployment plans may in many cases be influenced by the potential for DTS deployments to provide robust coverage,” the comments read. “Expeditious approval of the requested changes will improve service to viewers, encourage investment and speed the rollout of ATSC 3.0 services.”

Specifically, the NPRM seeks comment on allowing DTS signals to provide coverage to the edges of station’s services even when the signals unavoidably spill over a station’s authorized service area. The NAB says while small, this could have a significant impact on the economic and practical feasibility of DTS deployments.

APTS and NAB also said that petitioners specifically avoided asking for more aggressive approaches that had previously been rejected so as to continue to promote localism. “Indeed, facilitating the ATSC 3.0 rollout and allowing superior coverage through use of DTS will enhance localism as ATSC 3.0 provides the capability for broadcasters to provider hyperlocal, geo-targeted updates and alerts,” per the comments.

One Media also filed comments that said that the “modest” modification proposed by the FCC for DTS would boost localism.

The APTS and NAB comments concluded that there should not be a delay in moving forward with these changes to examine “hypothetical concerns over the impact of expanded DTS operations on secondary and unlicensed services.” The two organizations say there is no basis for the FCC to expand the spectrum rights of secondary and unlicensed services in this proceeding.

The full comments from APTS and NAB are available online. 

WASHINGTON—One Media, which is owned by advanced TV pioneer Sinclair, said the FCC should adopt the "modest" modifications to its plan for deployment of the ATSC 3.0 advanced broadcast transmission standard, but should also look to be a little less modest, including recognizing the value of distributed transmission to localism.

That came in comments on the FCC's recent NPRM.

One Media said that the commission should also consider 1) furthering maximization of broadcast coverage areas; 2) "[r]ecognizing the importance of this proceeding, and policies supporting the advancement of Next Gen TV services, to promoting localism and the ability of broadcasters to continue serving the public interests"; and 3) streamlining the licensing process.

The FCC voted unanimously in March to adopt a Notice of Proposed Rulemaking (NPRM) seeking comment on a broadcaster proposal to allow broadcasters greater flexibility in using distributed transmission systems (DTS) to deliver new ATSC 3.0 signals.

The FCC said, and broadcasters agreed, that allowing that flexibility with the new advanced TV broadcast standard would get those signals to hard-to-reach viewers, improve indoor reception and be more efficient with the spectrum, a big priority for the FCC.

The FCC's proposal is responsive to a petition by the National Association of Broadcasters and America's Public Television Stations to change the current DTS rules, which were adopted during the last transmission sea change—to digital, to allow for single frequency networks (the DTS systems comprise "two or more transmission sites located around a station’s service area, each using the same RF channel").

The item sought comment on whether and how to allow signals to exceed a TV station's service area by more than the current de minimis (minimal) amount. The FCC also wants input on the possible impact of extending the signals on other uses, including low-power TV stations and whether to extend the signals of current ATSC 1.0 signals as well. Broadcasters currently use translators to boost their signals at the fringes of the service area and in other areas where terrain weakens a signal, but translators usually use a different channel, while DTS use the same channel.

Computer companies, most notably Microsoft, have argued against the rule change, saying it could be "catastrophic" to its rural broadband rollout and arguing broadcasters could get what they want through existing rules. Microsoft is using the "white spaces" between TV signals to deliver it.

The FCC had signaled concerns about the DTS expansion to areas that could not be reached with a single antenna because it could undermine localism.

One Media begs to differ.

"[A]s the deployment of ATSC 3.0, and adoption of the proposed rules in the NPRM, together promote localism by allowing stations to provide better over-the-air coverage throughout the contour and the delivery of tailored local content to more viewers. Moreover, the recommended interference contour will prevent DTS stations from encroaching on the service of stations in adjacent markets."

It also said DTS will allow for "hyper" localization.

ATSC 3.0 offers at least three ways to make reception easier that aren’t available or are difficult to implement in 1.0. One involves providing a stronger signal to the viewer. The others make the signal more robust so less signal strength is required.

DISTRIBUTED TRANSMISSION SYSTEM (DTS, AKA ‘SINGLE FREQUENCY NETWORK’) 

A DTS consists of multiple transmitters on the same frequency spread throughout the coverage area to provide a uniform strong signal for indoor reception throughout the coverage area. DTS was available for ATSC 1.0, but it was difficult to provide a uniform signal without creating areas of self-interference. ATSC 3’s COFDM modulation can eliminate that interference.

A major advantage of a DTS is that, by providing a stronger signal level, less of the broadcast channel’s capacity has to be devoted to error correction and higher order (less robust) modulation constellations can be used, which provide greater efficiency (bits per Hertz). A DTS is the ideal way to improve ATSC 3.0 reception as not only is the stronger signal easier to receive over a wider area, but the higher data rates allow for more program streams and higher resolution video.

The problem is that building out a DTS involves setting up multiple transmitter sites, getting a signal to those sites and in addition to capital cost, extra operating costs (leases, power, etc.) for multiple transmitter sites. For a DTS to provide reliable indoor coverage to an entire market, some FCC rules changes are also needed. These are outlined in the recent FCC NPRM FCC 20-43.

SACRIFICE BITS FOR ROBUSTNESS

Unlike ATSC 1.0, ATSC 3.0 allows a trade-off between robustness and data rate. It is possible to transmit a signal that can be received at or below the noise level (0 dB SNR) but this requires a robust modulation method (least efficient) and a large amount of error correction coding, leading to a very low data rate.

There is almost infinite flexibility in determining the trade-off, so a broadcaster could decide to sacrifice some bits using Time Division Multiplexing (TDM), for example, from the less robust but higher bit rate streams to create a more robust physical layer pipe (PLP) on the signal. Because data rate would be limited, the robust stream would likely be limited to standard definition (SD) or perhaps 720p HD, depending on how capacity was allocated between the main and robust PLPs.

SACRIFICE POWER FOR ROBUSTNESS

This may sound like a contradiction, but one way to come up with a more robust signal is to split the signal into two PLPs by dividing up power (instead of time or frequency) using Layered Division Multiplexing (LDM). A core layer PLP carries the robust signal and an enhanced layer PLP overlays a less robust signal at reduced power over the robust signal.

The reduction in power means the enhanced layer has less signal at the receiver, but because the less robust signal does not give up time or frequency to the robust layer, more capacity is available to offset the reduction in power. As with the TDM example, the trade-off between robustness and capacity remains. I describe some early tests of LDM in my 2015 article “LDM—Stacking Signals for Improved Performance.”

All three of these methods can be combined, providing even more flexibility.

WASHINGTON—The FCC today adopted a Notice of Proposed Rulemaking (NPRM) that would modernize its Distributed Transmission System rules to enable TV broadcasters to enhance coverage from NextGen TV (ATSC 3.0) single frequency network on the edge of coverage areas.

“America’s Public Television Stations applaud the action taken today by the FCC, a welcome endorsement of changes in the current rules that will allow broadcast television stations to unlock the benefits of NextGen TV through DTS operations that better serve their viewers while preserving their commitment to localism and avoiding interference issues,” said Patrick Butler, president and CEO of APTS.

The NPRM seeks comment on technical changes proposed by APTS and NAB to the agency’s rules to allow—with certain limits—signals from SFN sites to “spill over” beyond the authorized service area of a station “by more than the ‘minimal amount’ currently allowed” by the rules, the FCC said.

In an October 2019 rulemaking petition filed by APTS and NAB, the organizations asked the FCC to permit stations to deploy SFNs in which the noise limited service contour (NLC) of a DTS transmitter “may exceed the reference facility’s (i.e. the station’s primary transmitter’s) NLC. However, in the case of UHF stations, the 36 dBu F(50, 10) interference contour of a DTS transmitter may not exceed reference facility’s 36 dBu F(50, 10) contour.

The petition noted that the value was proposed because it will ensure interference protection for co-channel Class A and LPTV station operators. Similar interference avoidance was proposed for low- and high-VHF channels.

“These small changes will improve coverage throughout local public television stations’ service areas and improve their ability to offer robust mobile service. It will also enhance spectrum efficiency by reducing the need for television translators operating on redundant channels,” said Butler.

NAB and APTS noted in its petition that the proposed changes are needed to allow broadcasters and viewers alike to benefit fully from the potential of ATSC 3.0. 

In its NPRM, the agency seeks comment on whether it should change its spillover limits. “In particular, we seek comment on Petitioners’ claim that such a rule change is needed now as the industry embarks on ATSC 3.0 deployment,” the NPRM said. The commission is also seeking comment on whether to adopt the 36 dBu F(50, 10) interference contour as the limiting contour for spillover.

The FCC also seeks comment on the Comparable Area Approach adopted as part of its 2008 DTS Order and whether to retain it as part of its 2017 NextGen TV Order. It also wants to know if the proposal would make it possible for broadcasters to serve additional areas without going through a competitive bidding process, and seeks comment on how such changes would affect the agency’s policy goal of promoting localism.

NAB welcomed news of the NPRM. “NAB applauds the Commission for proposing deployment of single frequency networks allowing broadcasters to better serve viewers while preserving our commitment to localism,” said NAB President and CEO Gordon Smith. “These SFNs could improve service throughout a station’s coverage area and, in particular, near the edge of the coverage area. SFNs could also improve mobile reception and allow more efficient use of broadcast spectrum. FCC staff is to be commended for moving this item quickly, and we look forward to establishment of final rules.”

The NPRM is available on the FCC website.

WASHINGTON—The Merrill Weiss Group in reply comments filed with the FCC this week sought to “set the record straight” regarding misunderstandings or mischaracterizations of proposed amendments to the FCC’s Distributed Transmission System rules (found in Section 73.626 of the Commission’s rules).

Penned by S. Merrill Weiss, the filing is presented to the agency as a Frequently Asked Questions (FAQ) document that discusses the proposed changes, parts of the rule where no suggestion of amendment has been made and how the changes would affect other spectrum users.

Weiss, who pioneered DTS (also known as single frequency networks) use for ATSC 1 systems, including development of a method to synchronize transmitters in an SFN, cautioned the agency not to delay acting on the proposed changes to DTS rules. Doing so could result in “missed opportunities” causing harm to the TV broadcasting business, the filing said.

“Deciding to wait until more is learned about the operation of DTS networks in an ATSC 3.0 environment will preclude the deployment in a manner permitting full service to broadcasters’ service areas from the start, when they perhaps can have the greatest impact,” it said.

“The time for enabling improved service to the public through improvements of the DTS rule is now,” the filing said, adding that the petition should become a Notice of Proposed Rulemaking “without delay.”

A total of 21 questions are answered in the FAQs submitted as part of Weiss’ reply comments. Among the questions addressed are:

• Will the proposed rule modifications expand the defined service area beyond that defined under current rules in which a station can locate DTS transmitters? “No, they do not,” it said.
• Do the changes expand the defined service area beyond that defined in the current rules in which a station can expect interference protection? No, again is the answer, the filing said.
• Under the rule changes will stations be allowed to use a combination of antenna height and transmitted power greater than under the current rule? Once again, the answer is no.

The FAQs also spell out the main difference between the current DTS rule and the proposed rule. “The proposed rule changes the way in which the maximum field strength in certain directions from each transmitter in a DTS network is limited,” the filing said.

The questions and answers also address why the change in maximum field strength of DTS transmitters is needed, how the field strength is currently limited, how the field strength of DTS transmitters would be limited under the proposed rules and how the Interference Area Distance in the proposed Table of Distances would be determined.

The FAQs also explain how the changes would benefit full-service broadcasters as well as LPTV broadcasters, TV translators and Class A stations. Finally, the Q&As address whether the changes amount to “a ‘give away’ of large coverage areas to broadcasters” (no), and if the changes would make TV white spaces “all but unusable” (no, again).

The filing, which includes the FAQs, is available online.

For a comprehensive source of TV Technology’s ATSC 3.0 coverage, see ourATSC3 silo.

WASHINGTON—Broadcasters want to take a closer look at the FCC’s rules when it comes to Distributed Transmission Systems, aka single frequency networks, and its service limits.

This is the early take away from comments filed in regards to a joint petition from APTS and the NAB that specifically asks the FCC to amend its rules regarding DTS for the ATSC 3.0 rollout. Nearly all of the comments submitted to the commission’s ECFS are in support of a Notice of Proposed Rulemaking on the subject, the only dissension thus far comes from Microsoft.

The computer company is the only commenter as of yet to outright oppose the joint petition. Even so, its comments explain that it supports the idea of using SFNs to better utilize the ATSC 3.0 standard, it just does not feel new rules are needed.

“[W]e believe the commission was fundamentally correct in its Next Generation Broadcast Television Standard Report and Order when it concluded that ‘the rules the commission already has established to authorize a DTS station generally are adequate to authorize an ATSC 3.0 SFN station.’ Thus, while we support the use of DTS, we do not support the rule changes proposed in the petition, which appear to go well beyond what is needed to fill coverage gaps within broadcasters’ service areas,” Microsoft wrote. It was the only submitted comments to outright oppose the joint petition.

Ark Multicasting Inc., while ultimately supporting the petition, also warned against “unintended consequences that could freeze technology and markets.”

Most of the comments support the concept that SFNs will be better suited to provide better reception for ATSC 3.0.

“The NEXTGEN TV rules adopted by the FCC build upon an existing license framework that, while perhaps reasonable for ATSC 1.0 transmissions, needlessly limits the ability of broadcasters to take full advantage of the next-generation standard,” Nexstar’s comments read. “The Commission should take this opportunity to remove that limitation and provide broadcasters with the flexibility to fully embrace single frequency networks to expand the delivery of local content and maximize the efficiency of their assigned spectrum.”

All of the filed comments can be read on the FCC’s ECFS page.

WASHINGTON—After receiving a petition from the National Association of Broadcasters and America’s Public Television Stations on Oct. 3 asking for updates to the rules surrounding single frequency networks as broadcasters attempt to build out ATSC 3.0, the FCC has officially filed a public notice seeking comments on the petition.

Single frequency networks, also known as distributed transmission systems (DTS), allow broadcasters to extend RF coverage by building transmission systems that fill gaps and improve reliability and reception quality.

With the rollout of ATSC 3.0, otherwise known as NEXTGEN TV, expected to begin within the next year, the petition states that “many broadcasters are interested in exploring the advance capabilities of ATSC 3.0 to facilitate the use of DTS.” The petition specifically asks for more flexibility in the current rules so broadcasters can deploy more transmitters at the edge of their coverage areas, which they believe would allow them to improve their service, mobile reception and spectrum efficiency.

The full petition is available on the FCC’s Electronic Comment Filing System.

The public notice is calling for any comments regarding the petition to be filed through the ECFS by Nov. 12. The reply comment deadline will be Nov. 27.

The complete FCC public notice is available here.

For a comprehensive source of TV Technology’s ATSC 3.0 coverage, see ourATSC3 silo.

Click on the Image to Enlarge

PORTLAND, ORE.

—A low-power broadcaster in the Pacific Northwest plans to fire up ATSC 3.0 broadcasts on multiple frequencies over a distributed transmission system, or DTS. WatchTV of Portland had requested an experimental license from the Federal Communications Commission to allow its Portland-area Class A low-power stations to be used for a ATSC 3.0 DTS. The request was granted Tuesday, Feb. 14. WatchTV has six months to run its experimental broadcasts with the caveat that they don’t cause interference.

“We... conclude that the public interest would be served by the grant of this request since the information obtained from the experiment may be valuable to the commission’s broadband initiative. However, we caution you that an experimental facility is secondary and may be summarily terminated if the operation causes interference to any other broadcast facility, ” the commission said in its

Feb. 14 determination

.

Specifically, WatchTV requested it be allowed to use its KKEI-CD facility, broadcasting on Ch.38, to transmit a ATSC 3.0 signal over a DTS configured of two more sites. ATSC 3.0 broadcasts also will be transmitted on frequencies occupied by three more WatchTV stations that share the KKEI-CD transmitter site—KORS-CD at Ch. 16; KOXI-CD at Ch. 20; and KORK-CD at Ch. 35. The primary signals of each of these stations will be carried on a fifth WatchTV licensee, KOXO-CD, transmitting on Ch. 41.

“All spurious emissions on all channels will be confined within the limits applicable to ATSC 1.0 transmissions,”

WatchTV’s application

stated. “Because ATSC 3.0 is an OFDM‐based system, the potential for interference to other stations transmitting ATSC 1.0 facilities will be less than the potential from the existing licensed ATSC 1.0 facilities of the four stations. The emission mask at all three transmitter sites will be stringent.”

Facilities at the two DTS sites, Spud Mountain and Bald Peak West, (

Fig. 1, above right

) were designed to ensure that their 51 dBu signal contour remained within the contour of the KKEI-CD originating facility, WatchTV said.

The broadcaster said its objectives included learning more about ATSC 3.0 signal propagation characteristics “in a geographic area with much more uneven terrain than exists in the Washington‐ Baltimore area, where Sinclair Broadcast Group, Inc. conducted its recent experimental operations.” Additionally, WatchTV said it would explore delivery of multiple data services alongside various TV formats, including Ultra HD, and that it wanted to see if multifrequency network broadcasting would increase the data capacity of ATSC 3.0.

“WTV’s experiment will use four channels. WTV’s program will be the first experiment of which it is aware in which spectrum will be available to test spreading data across multiple TV channels while each channel is also transmitting single‐channel video content,” the WatchTV application stated.

WatchTV further said it wished to “explore the benefits of distributed antenna systems by transmitting simultaneously from three transmitter sites initially, with the possibility that a request will be filed at a later date to add more sites,” and to “explore the robustness and capabilities of a multi‐frequency system to deliver video and other content to mobile receivers”

Greg Herman, WatchTV president and CEO, told Mike Gravino of the LPTV Spectrum Rights Coalition he was grateful to the FCC staff for their “rapid assessment and approval of our experimental application.

“As we have contended for many years, television broadcasters in the United States are in dire need of a new and technologically advanced television broadcasting system.

“The world has passed us by in the last decade, and left us in a place where broadcast television spectrum is no longer relevant in the daily lives of average Americans. This must change, and we believe that ATSC 3.0, next-generation TV is an essential step in this evolution.

“Further, we are excited and encouraged to demonstrate the essential role Class A and LPTV broadcasters and their spectrum can play in the new ATSC 3.0 ecosystem. We want to be first and we want to be the best we can be!”

For more

TV Technology

coverage, see our ATSC 3.0 silo. Also see....
Feb. 17, 2011

“

WatchTV Multicast Broadcasting Proposal Nixed by FCC

”

WatchTV had an idea for making more efficient use of the spectrum authorized for its low-power TV stations.