ATSC 3.0: A New Broadcast Standard for the UltraHD and Mobile Age

For the past two years, the dominant story in TV and displays has been the advent of 4k or UltraHD.  Here at Audioholics, we oppose the use of the term 4K when referring to the new display technology and prefer the moniker UltraHD because it is a much more accurate description of the technology.  The UltraHD standard is not simply about more pixels. Rather, the move towards UltraHD is about a series of display enhancements including greater dynamic range, a wider color gamut, and of course 4 times the resolution of 1080p (FullHD).

While the home theater world has become somewhat hyper-focused on this evolving standard, we’ve seemingly forgotten to give any mention about good old broadcast television.  It was not too long ago, on Friday, June 12, 2009, that standard definition television (SDTV) went by way of the dodo.  Since then, all television broadcasts have been sent in high definition (HD), or to be more precise, 1080i or 720p with up to 5.1 multichannel audio.

Many may not remember that in order for the HD transition to take place, we had to make an underlying change in technology from analog to digital TV.  The old analog standard, NTSC, was replaced by the new digital standard, ATSC (Advanced Television Systems  Committee), at the same date as the Digital TV cutover.  From that point on, to get digital TV, you needed an ATSC tuner to pickup digital TV signals.  

It was that ATSC 1.0 standard that set the 16:9 aspect ratio of today’s TVs; image resolution up to 1920 x 1080 pixels; 5.1 surround in Dolby AC-3 format; and up to six SDTV sub channels (hence the introduction of x.1, x.2, etc as a sub channel option on new TVs).

While display technology has been evolving and making its way into the consumer market, digital transmissions have remain unchanged since the ATSC 1.0 standard.  From a technology point of view, today’s broadcasters and today’s UltraHD displays ATSC TV tuners can only support up to 1920 x 1080 pixels.  They cannot support any of UltraHD’s technology advancements!

We also know that viewer habits have been changing dramatically.  Unlike 20 years ago, many individuals are no longer consuming digital media solely on home TVs.  Instead, computer-based and mobile content consumption on smart phones and tablets has become a new norm in today’s day and age.  

Behind the scenes, the Advanced Television Systems Committee has been working to update the ATSC standard.  Increasing pressure on the broadcast spectrum; increasing entertainment options; the need to provide different business models to broadcasters; and mobile entertainment lifestyles are among the many things that precipitated the move to update the ATSC standard.  That new standard will be called ATSC 3.0.  

What about ATSC 2.0?

Wait a minute.  You may be wondering, “We were just talking about ATSC 1.0.  What happened to ATSC 2.0?”  There is an ATSC 2.0 standard, but up until this point, ATSC 2.0 has been largely overtaken by the new focus on ATSC 3.0.  ATSC 2.0 had been looking to incorporate some set top box style features into broadcast TV such as streaming Internet services, video on demand, and interactivity while also giving broadcasters and advertisers some capabilities like audience measurement and targeted advertising.  You won’t see ATSC 2.0 released to the public, however.  Given where technology has evolved, ATSC 2.0 will be leapfrogged by ATSC 3.0.  Many of the technologies developed for ATSC 2.0 are expected to be supported in the new ATSC 3.0 system.

While ATSC 2.0 was envisioned to be backwards compatible with ATSC 1.0, ATSC 3.0 will be a completely new standard and incompatible with current broadcast systems.  Therefore, one of the challenges that the ATSC standards committee will face is providing enough improvements in performance, functionality, and efficiency to warrant a wide-scale implementation of a non-backwards-compatible system.  The standards committee understands that point clearly and has outlined around 140 requirements for the new ATSC 3.0 standard to make the transition a compelling one.  

When you hear about what some of these new features will be, you’ll likely agree that the standards committee has put a tremendous amount of thought into this process. I had the chance to sit down and have an exclusive conversation with Rich Chernock*, who is chairing the ATSC 3.0 standards committee (TG3).   

The main ATSC 3.0 Committee is comprised of hundreds of representatives from across the globe.  The Committee is made up of individuals from a variety of disciplines including broadcasters, CE manufacturers, research institutions, and industry experts.

The ATSC 3.0 Committee is broken up into a number of working committees, including: The Physical Layer Committee, which is overseeing issues like RF modulation; the Middle Layer Committee, which is responsible for things such as delivery, synchronization and metadata; and the Application Layer Committee, which is overseeing elements such as audio and video codecs and interactivity.  I want to acknowledge and thank Rich for his time and providing much of the information that follows.   

What are the Features of ATSC 3.0?

Rich conveyed to me that ATSC 3.0’s goal is to close the gap between today’s tech and tomorrow’s TV while also adapting to consumer’s viewing habits. The ATSC 3.0 standard looks to enhance the viewing and listening experience with Ultra HD video and immersive audio, but it is also being designed with mobile and IP-based services in mind.  

The ATSC 3.0 standard will include UltraHD video up to 3840×2160 at 60 fps.  Other elements of the UltraHD standard such as high dynamic range (HDR), wider color gamut, and high frame rate (HFR) will be included in the standard.  Rich shared with me that ATSC Committee is partly waiting for some of these UltraHD standards to become more stable across the entire industry.  While many standards bodies work in isolation, the ATSC 3.0 Committee is in close communication with many of the other major standards bodies such as SMPTE and CEA so that they could ideally adopt the same standard HDR, color, and HFR standards because they all want to go in a similar direction.  

The ideal goal is come as close as possible to uniform standards between physical, streaming, and broadcast media.  However, whatever the goal, differences in technological reality (such as a wider, noise free data pipe with physical media vs. a smaller, noisy pipe) may lead to differences in the final spec.  Whatever ultimately happens, it’s incredibly refreshing to see an attempt to try and reproduce content across all mediums to replicate the artistic intent of the author. 

The audio front of ATSC 3.0 promises to be revolutionary and spectacular.  The ATSC 3.0 audio standard will support immersion and height.  It’s expected that there will be support for at least 7.1.4 configurations scaling up to configurations as large as 22.2.  The ATSC body is currently in the midst of selecting the audio system for the standard.  The two major contenders are Dolby with their AC 4 standard, and the MPEG-H Audio Alliance, which is comprised of Fraunhofer, Qualcomm, and Technicolor.  Both the Dolby and MPEG-H Audio Alliance proposals offer similar features, utilizing different technologies under the covers. 

ATSC 3.0 will support immersive audio.  A Dolby Atmos 7.1.4 configuration is shown here.  Image courtesy of Dolby

Interactive audio, the ability to control audio elements, and personalization will be part of the chosen standard.  For example, let’s say you are watching a sporting event and the announcer gets lost because of crowd noise or you just can’t hear the announcer through the center channel as clearly as you would like.  With ATSC 3.0, you’ll not only have the ability to control the dialogue level, you will also be able to select which announcer you want to hear.  Do you want the announcers from the home team, the away team, or just turn the announcers off altogether?  You will be able to do any or all of the above!

In the old days of audio, broadcasters had to generate different mixed audio streams for different devices.  If you didn’t have a mix for a particular device, then you didn’t get the audio.  For example, let’s say you were sending audio for home theater and then wanted to listen on a portable with earbuds. It doesn’t work well—from the channels to the audible dynamic range.  However, now with the new ATSC standard, all broadcasters will need to do is send one audio stream and your consumer device will know what your speaker setup is and then render the audio specifically for your setup. In other words, your device (receiver, tablet, phone, set top box, etc.) will know what your speaker setup looks like and what audio works best for your environment.  At this point, it’s unknown what will be needed for existing AVR and pre-pro owners to take advantage of this audio; but given where the technology and processing power is today, it shouldn’t require more than a firmware update to current models.

Audio and video aside, another major goal for the ATSC 3.0 standard is to be more flexible for broadcasters and much more useful to the consumer no matter what device they connect from.  As part of the ATSC 3.0 standard, in one 6MHz channel consumers will have the option to see, for example, an UltraHD TV signal targeted to a large display, an HD TV signal aimed at indoor reception on a tablet and a mobile stream for a handheld device on the move. Options such as “multiview” and “multiscreen” are also important, as is the option of choosing among standard definition, HD and Ultra HD resolutions.   Think about it.  ATSC 3.0 is a seismic philosophical shift.  For the first time in history, television programming will be conceived of apart from a traditional TV set and will be intimately tied to the Internet.

For the first time, ATSC 3.0 will also introduce support for IP-based broadband delivered content as part of the TV service.  In ATSC 3.0 broadcasting is going to be considered part of the Internet.  Broadcasters will have the option of sending some elements over the air and others over the Internet.  For example, let’s say you are watching TV and a storm is coming through your area and it messes up your antenna signal.  Your TV could be smart enough to transition to the Internet version of the broadcast so that you wouldn’t miss a beat.  Likewise, IP-based broadcasting support could bring alternate video angles, audio language support and more.  The bottom line is that by moving away from MPEG2 Transport Streams as a transport to pure IP (even in broadcast), all of these broadcast services will now be designed to work together.

To account for this major shift, the ATSC standards body had to rethink the very notion of broadcast reception.  At the physical layer of ATSC 1.0, there was only one operating point.  In lay terms, back with ATSC 1.0 broadcasts were strictly targeted to rooftop antennas, not to mobile devices (there were no multimedia-capable mobile devices in the early days of ATSC 1.0). 

However, in and around the ATSC 2.0 time period, there was the introduction of ATSC Mobile.  ATSC Mobile added thee operating points so that you could add more levels of robustness to target mobile devices.  More robustness, however, means less packets and lower quality.  That’s unacceptable with today’s higher resolution devices.

In ATSC 3.0 that’s all changed for the better.  Now, there will be a huge range of operating points from the rooftop antenna mobile all the way down to the operating point where the signal is 3db less than noise. In other words, you could potentially watch TV in a tunnel.  

There is deliberately such huge range of operating points in the new standard so that the broadcaster can choose what they want to do .  The station can broadcast in multiple modes—over the air, mobile, and medium rate for HD tablets—all at the same time.  The broadcaster is in control and can choose what they want to target.  

To illustrate this point in practice, Rich related a quick story about a demonstration in Cleveland a few weeks ago.  They took an old TV transmitter that had been used during the transition to HDTV.  That transmitter had been dark for years.  They then got an experimental license from the FCC and implemented one of the candidate proposals for the ATSC physical layer and put it on air to use as a proof of concept.  The intent was to get real world programming and start transmitting.  

They conducted a one day demo and were able to watch full HD programming while driving at 60mph on the highway in Cleveland and while driving around the urban canyons downtown.  They then went into a basement and were able to watch a SD TV (while an ATSC 1.0 receiver showed only noise).  Any programming anywhere on any device, how cool is that! 

 Over time, the ATSC has learned that technology keeps.  Transitions, as we well know, are painful.  Instead of creating a new system every time, the ATSC has learned to evolve gracefully through versioning without breaking the overall system.  With the ATSC 3.0 standard, the Committee has designed ways of signaling and mixing old and new elements.  That’s a big step forward.  \

Emergency Broadcast System Revamp

ATSC 3.0 isn’t just about broadcast entertainment.  It’s also about creating an intelligent emergency broadcast infrastructure.  ATSC 3.0 will bring Advanced Warning and Response Network (AWARN) capabilities.  Most people are not aware that in the event of an emergency and disaster situations, the only mass communications medium that keeps working is broadcast signals.  All these transmitters have been built to stay on the air in bad conditions.  They are battle tested and have been designed with generators and backup systems.  

ATSC 3.0 plans to take emergency alerting to the next level by including a digital wakeup bit in a broadcast.  If that bit is turned on, then your TV or device will power up automatically and inform you of critical information.  In the past, such information was limited to a text crawl on the bottom of your screen and an audio overlay.  That was OK, but certainly not optimal.

Now, with the AWARN infrastructure emergency response broadcasts can be pushed out along with maps, evacuation routes, video clips, and even information on how to recover from disaster.   The AWARN infrastructure will be both proactive and reactive.  

Your ATSC 3.0 compatible device will also know where it is physically located.  Therefore, the capability will exist to target information specific to your geographic location.  There is also the idea of providing encrypted information directly to first responders too.   

When will we see ATSC 3.0?

Given all these potentially incredible features, when will we see the availability of ATSC 3.0?  According to Rich, the goal is to have the majority of standards in Candidate Standard Phase by the end of this year.  When something enters the Candidate Standard Phase, it is then published and people can access the details, and build prototypes for testing.  Once a standard has been tested and the bugs have been worked out, it can then go to final ballot.  

Given that reality, there is a very real possibility that we may see ATSC coming as early as the end of 2016.  In anticipation of that reality, to assist the organizations working on transition planning, the ATSC 3.0 Committee is already discussing different options for the transition to try and ensure compatibility (an HDMI converter stick is one such possibility being floated around).

Whenever ATSC 3.0 finally comes into our homes, it will clearly be a watershed moment in the history of broadcasting.  It’s not just the technology that is promising, but also the underlying philosophy that the ATSC Committee has adopted as part of its work.  I think all of us owe the Committee a great deal of thanks for all their work and can’t wait to see it up close in operation in our homes.

You can stay abreast of the ATSC 3.0 Committees work through their regular updates at: http://atsc.org. 

*Note: Dr. Chernock is currently Chief Science Officer at Triveni Digital. Previously, he was a Research Staff Member at IBM Research, investigating digital broadcast technologies. Dr. Chernock is chairman of the ATSC Technology Group on ATSC 3.0 (TG3) and chairs the AHG on service delivery and synchronization for ATSC 3.0. He was previously chairman of the ATSC Technology and Standards Group (TG1). He is also the Distinguished Lecturer Chair for IEEE BTS. In another life, he used transmission electron microscopy to study materials characteristics for advanced ceramics packaging and semiconductor technology at IBM. His ScD was from MIT in the field of nuclear materials engineering.