Article: Diginets come of age

[TNGuy84]

"What is the advantage for consumers and TV stations to switching to ATSC 3.0? Is it worth the trouble and cost?

Is this just another overhyped boondoggle?"

Long-term, it would make financial sense to a TV station that wanted to attract more viewership with additional channels (hence more advertising space). From my understanding, the new standard offers more bandwidth and better compression capability. Stations wouldn't be limited to the 19 megabit amount set by the current standard. I've seen estimates as high as 36 megabits. ATSC 1.0 uses MPEG-2 compression, which was developed in the 90s. ATSC 3.0 uses the more modern MPEG-H HEVC / H.265 codec. A station could squeeze in more SD and HD channels with the higher allotment of bandwidth and with better compression rates without sacrificing as much picture quality. It makes no sense to buy 4K televisions that can produce far better video than any in the past and still be watching TV programming with tuners based on 20+ year old technology. When viewers see the difference in store displays using the new tuners to receive the new signals that look better because of less compression artifacts, they'll be glad to migrate.

 

[comfortably_numb]

Stations wouldn't be limited to the 19 megabit amount set by the current standard. I've seen estimates as high as 36 megabits.

Thank you. I was wondering what the available bandwidth of an ATSC 3.0 frequency would be.

 

[Jim5506]

So one ATSC 3.0 station will occupy the bandwidth of two ATSC 1.0 stations plus have better compression algorithm.

They should be able to pack 4X the data on their signal.

 

[harshness]

So one ATSC 3.0 station will occupy the bandwidth of two ATSC 1.0 stations plus have better compression algorithm.

The RF bandwidth will still be 6MHz. How it is used will be more efficient but the modulation may need to be adjusted and error correction fiddled with if there turn out to be issues that weren't anticipated or they were being too conservative.

Even with potentially much better compression and modulation, it is reasoned that UHD channels may have to run solo on a frequency.

As much as the proponents have crowed about how well the scheme works, putting something in the hands of the public with their mud flaps and foil-wrapped rabbit ears will surely offer many surprises. I think that more than a few stations are hoping to see the repack force viewers into installing broader spectrum antennas.

 

[dhett]

Did that happen with the ATSC 1.0 transition? No. It took a mandate from the Government to force all the TV stations to switch over to ATSC 1.0 AND the digital converter coupons paid for with tax dollars to make the switch happen.

I see several differences between now and the analog-to-digital transition.

1. Television station owners are leading the way to implement ATSC 3.0, dragging the government along.
2. Television is lagging behind non-television in terms of content technical quality. That is, you can find 1080p and 4K content on satellite or online to watch on your 1080p or 4K TV set, and viewers already have UHD sets. The point about buying new TVs versus new tuners is well taken; I stand corrected there. But viewers are already ahead of broadcast TV.
3. Non-broadcast content is by far more ubiquitous today than it was during the analog-to-digital transition, so where broadcast TV was the biggest voice during the analog-to-digital conversion, it's now just one of many voices, and one of the quieter voices. Viewers are getting most of their content elsewhere; broadcast TV needs ATSC 3.0 just to have a chance to compete.
4. ATSC 3.0 has benefits to both viewers and station owners. Viewers can get either higher-quality content or a higher quantity of content in the same 6 MHz bandwidth, depending on what the owners provide. If they want, viewers can also integrate OTT content into their broadcast viewing. And when they do, station owners can take advantage of the ability to do targeting advertising. Improved forward error correction and multipath rejection benefit both viewer and owner. ATSC 3.0 will offer improved mobile viewing; ATSC 1.0 is unsuitable for mobile viewing.

If there is government involvement, it will be solely for the purpose of buying votes, because it won't be necessary.

 

[harshness]

I see several differences between now and the analog-to-digital transition.

Television station owners are leading the way to implement ATSC 3.0, dragging the government along.

The downer in me thinks they're (unintentionally) giving them just enough rope to hang themselves.

Non-broadcast content is by far more ubiquitous today than it was during the analog-to-digital transition, so where broadcast TV was the biggest voice during the analog-to-digital conversion, it's now just one of many voices, and one of the quieter voices. Viewers are getting most of their content elsewhere; broadcast TV needs ATSC 3.0 just to have a chance to compete.

It isn't so much that they want better content (they're paying Hulu and Netflix for the same content) but rather when and with as much advertising as they choose. Next-Gen isn't going to help with that.

ATSC 3.0 has benefits to both viewers and station owners.

Statements like this should include the word "potentially".

Improved forward error correction and multipath rejection benefit both viewer and owner. ATSC 3.0 will offer improved mobile viewing; ATSC 1.0 is unsuitable for mobile viewing.

The repack will put these stations in a band that requires larger antennas and I suspect most of the mobile claims are built around Single Frequency Networking (SFN; a sort of cellular model for TV) and may not be realized where SFN isn't deployed.

 

[dhett]

The repack will put these stations in a band that requires larger antennas...

Not quite. The only full power and Class A stations changing bands are those who volunteered to do so and took a payout from the FCC. The remaining stations that were repacked remained in the same band: V-Lo => V-Lo, V-Hi => V-Hi and U => U. Some LPTV/translator stations had to change bands, but in Arizona,
which has hundreds of LPTV/translator stations, I can only think of three that requested to move from U to V-Hi, and none of the three were forced to do so by a lack of available UHF channels.

...I suspect most of the mobile claims are built around Single Frequency Networking (SFN; a sort of cellular model for TV) and may not be realized where SFN isn't deployed.

Nope. The very nature of OFDM and the way it is to be deployed will improve mobile reception, even where there is no SFN. And for those places that do deploy an SFN, that will be an added bonus.

And speaking of SFN, it's already been proven in Europe that it will succeed with ATSC 3.0 where the Distributed Transmission Systems (DTS) failed with ATSC 1.0. Theoretically, it was supposed to be possible to have an ATSC 1.0 DTS where signals overlapped and long as the signals were completely synchronized. That proved not to be the case, as multipath interference was still a problem. ATSC 3.0 features improved multipath handling, and it's not just theory.

 

[harshness]

Not quite. The only full power and Class A stations changing bands are those who volunteered to do so and took a payout from the FCC.

That may be how things are in your market but in all cases, channels that were using RF>37 are moving regardless of whether their low power or Class A. Dismissing stations (or translators) that aren't full power isn't fair.

In larger markets, that means delving into VHF-high and in the largest markets, VHF-low where there may not have been such usage before the repack.

The very nature of OFDM and the way it is to be deployed will improve mobile reception, even where there is no SFN.

No amount of engineering, testing or reasoning is going to change the antenna requirements for receiving VHF.

 

[TNGuy84]

One of the local stations in my market will be moving to VHF Low 2, but they got paid to do so. I'm in direct line of sight with the signal, but I worry that noise will play a role once the station moves to that channel. I've heard that all kinds of electronics can cause interference on that frequency. I read one guy's account of how a dirty filter on his power line kept him from receiving the signal because it was making noise on the same frequency.

 

[dhett]

That may be how things are in your market but in all cases, channels that were using RF>37 are moving regardless of whether their low power or Class A. Dismissing stations (or translators) that aren't full power isn't fair.

In larger markets, that means delving into VHF-high and in the largest markets, VHF-low where there may not have been such usage before the repack.No amount of engineering, testing or reasoning is going to change the antenna requirements for receiving VHF.

I think you need to go back and read for comprehension. Nobody is dismissing anything.

Full power and Class A stations were repacked into the same band as before repack unless they volunteered to move to Hi-V or Lo-V, or volunteered to turn in their RF channel entirely to channel share. That's nationwide, not just my market.

Low power stations that were not Class A were on their own. If they were above channel 37, or displaced by a primary rights station, they had to relocate wherever they could. Here's the thing: low power stations are primarily in the west, where, except for the largest markets (LA or Bay Area), spectrum is plentiful. Back east, especially in the northeast, where spectrum isn't as plentiful, and in the aforementioned western markets, there aren't near as many low power stations.

Let's look at markets: Portland has two LPTV stations changing bands: one from UHF to hi-VHF, and one from UHF to Lo-VHF. The outlying areas of NW Oregon have none. Seattle has one station going from UHF to hi-VHF. San Francisco? None. A few full-powers that took money to go to lo- or hi-VHF, but no LPTV stations. In fact, three LPTV stations are moving from hi-VHF to UHF. Similar story in LA: several full-powers taking money to go to lo- or hi-VHF, a couple of stations going from UHF to lo-VHF, one going from UHF to hi-VHF, and one going from hi-VHF to UHF. New York? One from UHF to lo-VHF, two from UHF to hi-VHF and one from lo-VHF to hi-VHF.

Looks like your theory isn't supported by facts.

 

[primestar31]

Much as I think Harsh is wrong in a lot of what is going on with ATSC 3.0, he's right, in that in fact ALL stations, ABOVE channel 37 regardless of what they are classified as, must move or go off the air if there's no space for them in their area.

 

[dhett]

No amount of engineering, testing or reasoning is going to change the antenna requirements for receiving VHF.

You do realize that mobile television worked just fine back in the analog days, don't you? And that was back when a VHF assignment was considered beachfront property, especially lo-VHF. A 1999 FCC Report acknowledged that COFDM would be better for mobile applications:

The COFDM system, on the other hand, has better performance in dynamic and high level static multipath situations, and offers advantages for single frequency networks and mobile reception.

So the physics of receiving VHF isn't the problem here. It's 8-VSB, the modulation standard behind ATSC 1.0, that's the problem. Switching to COFDM is the solution for making mobile TV viable again.

 

[dhett]

Much as I think Harsh is wrong in a lot of what is going on with ATSC 3.0, he's right, in that in fact ALL stations, ABOVE channel 37 regardless of what they are classified as, must move or go off the air if there's no space for them in their area.

That may be the case in the very largest markets, but with Phase 1 complete and Phase 2 underway, LPTV stations have generally been able to find room in the new TV band, and new FCC rules allowing channel sharing gives them more options. Some LPTV stations are even hosting full power stations in a channel sharing arrangement. I suspect that the cost of changing channels is more likely to cause a shutdown than the inability to find an available channel. What we do know is that LPTV stations that are operational should already have submitted their requests for a new channel assignment, and RabbitEars already lists those, so it wouldn't be too difficult to identify stations likely to shut down due to no available channel.

 

[comfortably_numb]

What we do know is that LPTV stations that are operational should already have submitted their requests for a new channel assignment, and RabbitEars already lists those, so it wouldn't be too difficult to identify stations likely to shut down due to no available channel.

The FCC was able to find new channels for all the LPTV stations in my market.

 

[harshness]

Full power and Class A stations were repacked into the same band as before repack unless they volunteered to move to Hi-V or Lo-V, or volunteered to turn in their RF channel entirely to channel share.

You say that as if UHF wasn't any wider than the VHF bands. My ABC affiliate (KATU) is moving from RF43 (647MHz) to RF24 (533MHz) that is a jump larger than three times the breadth of the VHF-Low band. To be certain, the higher the frequency, the broader the antenna coverage, but here the difference in wavelength is 3.9 inches.

The outlying areas of NW Oregon have none.

The outlying areas of Oregon are laced with translators. KATU has 16 of them (all below channel 37). The CBS affiliate (KOIN) has 14 translators with one at RF47. The NBC affiliate (KGW) offers 16 translators (all below channel 37). The Fox affiliate (KPTV) weighs in at 9 translators (all below RF37) and the PBS network is made up of 20 translators (all below RF37).

Perhaps not obviously, the state is divided into three long territories by the Coast Range and the Cascade Range, but I can't help but think there's going to need to be some care taken to avoid translators getting beat on by main feeds in the Willamette Valley if Next-Gen really "gets out" as well as some claim.

 

[harshness]

You do realize that mobile television worked just fine back in the analog days, don't you? And that was back when a VHF assignment was considered beachfront property, especially lo-VHF.

It didn't work anywhere I've been. We also have to remember that portable TVs back in the day had rabbit ears and later they threw in bow-ties or UHF loops. Maybe our idea of what constitutes "mobile" is different, but I'm thinking wireless devices (phones, tablets, laptops) rather than limos with amplified dipoles on the trunk deck or roof.

So the physics of receiving VHF isn't the problem here.

It absolutely is a problem where you need an antenna that will work with a nice fraction of 55-251" of wavelength. You can't demodulate what you can't resonate regardless of the modulation scheme.

 

[N5XZS]

It's funny that I good I used to have JC Penney BW analog CRT 5 INCH with AC or DC with plug in lighter.

It's funny how the analog video can hold on well good old NTSC being in the good old Volvo station wagon back in the early 80's. Grander of our time!

 

[harshness]

It's funny that I good I used to have JC Penney BW analog CRT 5 INCH with AC or DC with plug in lighter.

I've got a turn of the century 5" color model that could run on batteries but it didn't have a built-in antenna so you really couldn't go anywhere with it (unless you're one of those weirdos that has a TV antenna bolted onto their daily driver ).

I'm sure most of us oldsters will remember the Casio TV watch and hand-held portables that RS offered.

Speaking of RS, weren't they offering some manner for mobile TV outfit towards their end?

 

[TNGuy84]

I had both a 5" black and white portable tube TV and a Casio 2.3" LCD TV that I used during my teenage years on long road trips. As long as you didn't have any hills blocking your view, the reception was great. The picture stayed stable most of the time. The only times I had any problems with picture was when I would go away from the signal to a weaker reception area. In those types of locations, you could get horizontal lines through the picture and/or snow. The analog was pretty robust at mobile reception. I tried driving down the road with a portable set up years ago on ATSC and as soon as I hit 5 miles on the speedometer, the picture completely broke up.

 

[Jim5506]

Sometimes driving south out of Santa Fe on US 285 around Clines Corners I could pick up KOAT NTSC channel 7 out of Albuquerque. 60 miles on a whip antenna on my 6 inch radio shack AC/DC B&W portable.

Pretty fuzzy but the audio was clear.