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Some US stations are currently offering two 720p streams.
WQHS Cleveland offers 2 1080i streams and 2 480i streams using existing tech and their picture is fantastic.

I agree that 4K will NOT be the big mover/shaker with ATSC 3.0 but added HD channels and Datastreams/Datacasting will be.

From what I've read the new ATSC 3.0 would offer up to 6- 1080p streams utilizing HEVC compression, which is fantastic.

Sports and other fast moving video will benefit with 4K video but there are few broadcasters willing to shell out to produce content in that format. The big networks will do BIG sporting events in 4K but I highly doubt we'll see a Phoenix Coyotes vs Calgary Flames game done in 4K for at least a decade, too expensive to produce with not enough revenue on the table. I could be wrong, the League/Leagues could offer a 4K package but it will come at great expense to the consumer.
 

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The other thing that I think should be looked at when ATSC 3.0 gets the green light is the 6mhz assigned to each channel.

It's no secret that the FCC wants to do a re-pack, and sell off the upper end of the UHF spectrum. I have read a few articles about some tests concerning the sharing of a 6mhz block by two stations. That would give them each 3mhz.

From the article I read concerning the station in Cleveland running on a ATSC 3.0 test, with a 6mhz block, they manage to get about 26Mbs. And 15.7Mbs was assigned to the 4K stream.

Now simple math, divide that 26Mbs by two for sharing the 6mhz block and you get 13MBs per 3mhz. Now I'm no expert on this, and simply trying to understand this possible future ATSC 3.0 and sharing of the 6mhz block, tells me that 4K would have a problem being used. Or a station would be stuck only offering a 4K, and no sub-channels. Worse yet, a station assigned to sharing is stuck when its main network feed starts to get offered in 4K, and the station can't provide the 4K because of contracts it has to offer other HD channels on it's 3mhz.

Now this is just pure speculation on my part, and simply trying to point out that a re-think of the 6mhz assignment block may be in need. Lets say for the sake of arguement that the sell off happens, and we end up with Channels 2 - 36 (6mhz blocks) for TV. We would end up loosing 38-51. This totals 14 possible channels lost. And as I pointed out, sharing 6mhz blocks by two stations, would effect any possible use of 4K. And if there is no sharing, and each station gets a 6mhz block, then there is a limit to competition from smaller stations. No room for them in some markets. Or placing stations too close to each other, and thus effecting reception.

But, what if we end up dividing the blocks into 5mhz with ATSC 3.0. Just a very rough calculation on my part gave me TV channel assignment 2-41 (5mhz), using the same space of channels 2-36 (6mhz).
If ATSC 3.0 can get us 26Mbs at 6mhz, then we should be able to get 21.6Mbs with 5mhz blocks. This would still allow stations the ability to offer 4K if the network they are with goes that route. But, also room for a HD sub-channel. The increase in the number of channels available for license would increase as well. Leaving smaller stations (by that I mean stations not affiliated to the major networks), to stay on the air. I do believe some consolidation will occur with a re-pack, but not as severe if the assignment blocks are at 5mhz each.

Lets also look at it another way. If we remain with 6mhz blocks with ATSC 3.0, and a station can run a possible 5 HD_1080p streams, then just a single station can offer all the major US networks (CBS, ABC, NBC, FOX, CW). Now what happens in a market that now has three stations offering all those networks. Do the other two sign off. Shutdown? What happens to the local news those stations offered in their market. No longer available? But one station affiliated to the 5 main networks, offers only one local point of view news. Is this healthy for any market? Assigning a smaller block of 5mhz would put a limit on one station offering all the networks. Some will have to sign up with another local station. Thus keeping another local news source available.

Now everything I wrote here is speculation. But, something that might need to be considered with ATSC 3.0, and a possible re-pack of the TV frequency.

Remember, the 6mhz assignment per block was based on analog needs. Does it still need to be that if we are going to have to change the system once again when ATSC 3.0 kicks in.
 

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I haven't seen anything re 3 MHz assignments. When stations "share" a channel, they mean that multiple data streams are carried in the SAME 6 MHz Channel assignment.

There is a serious DISADVANTAGE to going to smaller bandwidth assignments, such as 3 MHz....which is why MOST of the World has gone to 7 MHz and 8 MHz channel assignments. Statistical Multiplexing is frequently used TODAY on SAT, CATV and OTA systems. In a well managed StatMux, some of the COMPOSITE data rate (e.g. 38 Mbps for CATV, 19.4 Mbps for OTA and now 26 Mbps in ATSC 3.0) is allocated to FIXED data streams, such as cyclic Software Updates to attached devices (that don't have I-N connections) and other revenue generating data streams, such as perhaps a subscription Stock Market Ticker service. The REMAINDER of the data stream can be allocated "AS NEEDED" across ALL of MULTIPLE Video Data Streams so that when one or more video program has "Action on the Field" requiring additional data rate, it is available to the program that most NEEDS it.

In the fol. TSReader Example, TWO 1080i and ONE 480i Video Programs are being carried....you can see the instantaneous data rate allocation in the Green Line Chart....the line at the bottom are the 3.3 Mbps of "NULL Packets" that were UNUSED, in excess of what the collective video programs needed:
SI Parsing by TSReader 2.8.47a
Note the the ALLOCATED data rate in the Summary section is actually a MAX value, arbitrarily set to a very high number, so the StatMux is the limiting factor rather than Allocating too LOW a Max Data Rate.

In the fol. TSReader Example, there is ONE 720p and several 480i programs in addition to ATSC A/153 (MPEG4) sub-channels for Subscription Starz and Shotime and "Airbox" programs (which I'm guessing are ALSO using the "shared" StatMux capacity)..

FYI: RabbitEars maintains a list of stations carrying TWO or more HD channels if you want to look at more examples:
RabbitEars.Info

The higher the Bandwidth Assignment, the more TOTAL Data Rate Capacity is available to be allocated across all Video Programs....which means that there will be fewer and fewer occasions that TWO or more Video Channels "NEED" more Data Rate capacity than is available. Hence higher Data Rate CATV and ATSC 3.0 systems can successfully pack MORE HD Channels than current ATSC....esp when using TWICE as efficient MPEG4 coding....or FOUR times as efficient HVEC coding expected in the future.......and 8 MHz Bandwidth systems are even better prepared to handle a larger number of HD Channels.
 

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6MHz scheme is here to stay

holl_ands said:
I haven't seen anything re 3 MHz assignments. When stations "share" a channel, they mean that multiple data streams are carried in the SAME 6 MHz Channel assignment.
Exactly - no need to carve up the channel allotments any smaller when data stream multiplexing can slice and dice each 6MHz slot so well. I've never come across the 3MHz idea before either.
Blackburst said:
Remember, the 6mhz assignment per block was based on analog needs. Does it still need to be that if we are going to have to change the system once again when ATSC 3.0 kicks in.
Keep in mind that soooooo much filtering in place today in passive signal gear is done according to 6MHz channel notches, and the stated goal of ATSC standards is to be transparent to such home and professional gear, so I cannot imagine the authorities forcing all that equipment to be obsolete. The 6MHz scheme is here to stay. :)
 

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I wasn't actually looking at the 3mhz. My point was the actual sharing of the 6mhz block by separate licensed stations. You do understand that though technically this might make sense, business people and corporations tend to want a well defined space of operations, staking their limits to the shared 6mhz block. Which of course effects the value of the licensed station, and the sale value as well. Sharing a block means defining the shared space by each party. It was a simple divide by two. So I was making the point that sharing a 6mhz block might not be a good idea.
 

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business people and corporations tend to want a well defined space of operations, staking their limits to the shared 6mhz block.
Businesses are concerned #1 on profit and this opportunity to share channels/spectrum opens up huge opportunities.

KLCS and KJLA were one of the first to try channel sharing and once the spectrum auction comes KLCS will be partnering with KCET, selling their spectrum to the government.

http://www.ctia.org/docs/default-so...rt-of-the-klcs-kjla-channel-sharing-pilot.pdf

https://en.wikipedia.org/wiki/KLCS
 

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Current ATSC systems are constrained to carrying only TWO HD (720p or 1080i) Channels...and a small number of SD programs (see RabbitEars summary above).

When ATSC 3.0 is widely implemented, I estimate it will be able to support ONE backward compatible ATSC 1.0 HD (1080i) program (abt 8 Mbps), ONE "4K" program (abt 15 Mbps Max per current Netflix practice) and perhaps ONE (1080i) or TWO (720p) HD programs in HVEC (abt 4 Mbps Max) & ONE or TWO low data rate H.265 Mobile feeds (depending on StatMux data rate reduction efficiency)....they'll be BEGGING for outside customers to share their costs when they FINALLY have sufficient capacity to share. Note that some channels could elect to NOT support either a backward compatible ATSC 1.0 program or a "4K" program and could support EIGHT HD (for 720p or 1080i using HVEC) programs plus many SD's (i.e. FOUR TIMES current channel practices). And it would only take a few more OTA Channels to provide DOZENS of SD Subscription Channel offerings, such as are found on CATV systems.

Bear in mind that HVEC Encoder/Decoders are at a very early stage in their development. Just as was seen in MPEG2 and then MPEG4 systems, the Data Rate Efficiency as well as picture quality will be significantly improved as HVEC becomes more readily available, allowing even MORE programs to be supported than what I've assumed.
 

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I guess no one has locked in the new signal. :frown

The Futurecast test is not the first, the first test was in Baltimore last year, I reported it elsewhere but it got zero hits.

Technicolor were the first to broadcast a 4k OTA picture in North America in conjunction with Sinclair Broadcasting.

Technicolor and Sinclair Broadcast Group Demonstrate Live Next Generation Television Platform for Broadcasters - Technicolor

Technicolor is now investing in HDR (High Dynamic Range) as a way to offer a more detailed picture, there are a couple of Cinema's capable of showing this new tech. Using HEVC this could allow a person with a 4K tv to see the 4k image while people with non 4K tv's would still get a hi def image.

One of the advantages of HDR is even a 1080i picture will be more vibrant than what we currently get.

Technicolor's tech could be the HDR TVs have been looking for | TechRadar

I think all these ideas are fantastic and bode well for the future of OTA Broadcasting.
 

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Cleveland was propagating over here pretty good last weekend.
Had we had the proper receiver, capable of the modulation scheme they are using, I am sure we would have.
 

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Had we had the proper receiver, capable of the modulation scheme they are using, I am sure we would have.
You didn't need any extra tech, the signal was also broadcast in ATSC 1.0 meaning any current tv could receive it.
 

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Ahh OK.. there is an RF 31 on the other side of Lake Erie (Woodstock) that also normally gets here when it's ducting, like right now:) So it's possibly just adding some co-channel interference at this end of the lake then. Any idea what the antenna pattern looks like?
Or what the Transport ID (TSID) is??
 

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I picked up this test signal way back on Apr 23. Identified as WI9XJY 31-1 with PSIP of "ATSC 3.0 Test Transmission" format was 1080i with test pattern bars. Saw it about 2-3 times since but not recently. Came in better than most of CLE when it was active.
 

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Forgive my lack of knowledge. But don't you need an ATSC 3.0 tuner to receive the signal?
 

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I never saw it here 30 mile west on cleveland. But 31.1-31.6 WPXD is Ion. During tropo i lock in on some times its overrides my pbs on 49.1 WEAO Akron OHIO
 

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Wheelman said:
Forgive my lack of knowledge. But don't you need an ATSC 3.0 tuner to receive the signal?
It was transmitted in regular ATSC like any other channel the few times I got it. They were probably in ATSC 3 much of the time during actual tests.
 

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Errata: "When ATSC 3.0 is widely implemented, I estimate it will be able to support ONE backward compatible ATSC 1.0 HD (1080i) program (abt 8 Mbps)..." [Obviously you can't simulcast ATSC 1.0 and 3.0...they're completely different waveforms.....or can you????]

I HAVE seen some recent articles re transmitting TWO different TV waveforms in the SAME Frequency Allocation....using Carrier-In-Carrier (CnC) Adaptive Cancellation Technique:
https://www.telesat.com/sites/default/files/telesat/files/whitepapers/Carrier-in-Carrier.pdf
http://www.comtechefdata.com/technologies/doubletalk

Should Read: "When ATSC 3.0 is widely implemented, I estimate it will be able to support ONE backward compatible MPEG2 HD (1080i) program (abt 8 Mbps)...." [Although not sure why anyone would NEED to do that.]
 

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holl_ands: "Note that some channels could elect to NOT support either a backward compatible ATSC 1.0 program."

If that happened widely, what would that do mean for existing ATSC tuners in televisions of the past 5 years?
 

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I'm not quite sure I understand your question....compounded by my fuzzy writing:
Should read "MPEG2" rather than "ATSC 1.0"...everything within the SAME ATSC 3.0 waveform.

When I originally wrote that paragraph, in the back of my mind there was rattling around this idea of POSSIBLY transmitting an ATSC 3.0 waveform at a 16-20 dB lower level below a backward compatible ATSC 1.0 waveform IN THE SAME 6 MHz CHANNEL using the Carrier-in-Carrier Adaptive Technique I mentioned above. And yes, the 3.0 waveform would have a limited Local LOS range. I had recently read the fol. TV Technology article by Doug Lung..which could just as easily be applied to ATSC 3.0 transmitted at a lower level than ATSC 1.0 Primary:
LDM?Stacking Signals for Improved Performance | TvTechnology
 

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NO, proposed ATSC 3.0 is NOT backward compatible with ATSC 1.0 HDTV's....it will probably be an entirely DIFFERENT (COFDM) waveform...similar to what the REST of the World is using (e.g. DVB-T2 type)....

As ATSC 3.0 is phased in onto a MUCH SMALLER number of available Channel positions [we'll probably lose Ch38-51 to cell phones], they won't be able to assign TWO Channel positions to ALL networks, like they did for the Analog to Digital Transition. But perhaps the MAJOR Networks MIGHT be allowed to Transmit ATSC 1.0 and 3.0 on two Channel Positions....for awhile. [But none of this has been worked out yet.....]

If they don't have to change Channel Assignments [which would affect Transmitter, Waveguide & Antenna Systems], some Stations can simply upgrade the Software in their old ATSC 1.0 Exciters to the new ATSC 3.0 Exciter Software Build....and others will replace the Exciter with a new one. [Biggest impact is upgrading infrastructure to support "4K" data streams....for those who chose to do so....it is probably NOT mandatory.]

So existing inventory of HDTV's will lose the ability to watch OTA TV programs until you bite the bullet and buy an External ATSC 3.0 STB or DVR....or new HDTV's. And I'll probably buy a ONE CONNECT Future Upgrade Kit for my Samsung UDTV....whenever they announce ATSC 3.0 Tuner availability for the Kit.
 
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