Home cinema - 1080P Standard?

On Sun, 20 Aug 2006 14:05:17 GMT Bob Miller wrote:

| As far as I know, the rules require ATSC and ATSC does not have MPEG4.
| Now, I would not mind having MPEG4. I realize the compatibility and
| upgrade issues involved. But I also believe they are substantially
| less than an upgrade in the modulation since the latter would affect a
| lot more engineering issues such as transmitter coverage areas. I'll
| stick with 8VSB and accept MPEG4.
|
| Simply not true but whatever. There are no coverage issues as Australia
| and all other countries who actually tested will attest to.

Comparing a COFDM transmitter to an 8VSB transmitter at the same average
power is one kind of test. I would expect that kind of test to be done
when evaluating whether to go with COFDM or 8VSB. I would also expect
both to give about the same fringe coverage level (e.g. signal against
natural noise). How they behave with issues like co-channel interference,
adjacent channel interference, reflections, and spurious emissions within
the channel can make the difference.

The above test does NOT apply to conversion of existing transmitters that
are designed for the 8VSB waveform to utilize COFDM. Unless the power
stages were designed for excesses to begin with (not a trivial cost at
the high power levels US TV uses), to run them from a COFDM modulator
means cutting back average power.

The tests ANY country did to decide which modulation to go with would NOT
reveal coverage issues that are applicable to conversion of EXISTSING 8VSB
transmitters to COFDM.

See if you can convince me that the broadcasters are NOW willing to dump
their 8VSB investment (e.g. the _entire_ transmitter) to go with COFDM.

| I find it very hard to believe very many broadcasters were willing to do that.
| I even find it hard to believe that about Sinclair.
|
| At the time it would not have cost that much. Would cost more now.

Of course now it costs more. So we're stuck with a decision that you
think was terrible I and think was not too bad.

| It's not about staying the course. If COFDM were the current modulation,
| and an opportunity existed to switch, at no cost, or a small cost, to
| something more dense like 8-VSB, 16-VSB, 256-QAM, etc., I would be in favor
| of that.
|
| Don't see anyone in the world considering switching from any COFDM
| system. Not even any discussions. Can't even imagine such a thing.

Show me a list of US broadcasters who have gone on record with the
position that they would rather have had COFDM from the beginning,
and for each of them, which would be willing to:

1. Dump their 8VSB investment to go with COFDM on the same channel at
the same average power level to retain the same fringe coverage.

2. Invest in a full fringe coverage repeater/translator system to go
with converting their existing 8VSB transmitter to COFDM at the
same peak power level, along with a complete changeover of channels
due to all teh restructuring, now all to be done on a flash cut
basis.

| If Sinclair wants to do that, then maybe they should sell off their
| stations and buy a few satellite transponders and build some new great
| satellite networks.
|
| Why should they sell off their stations when they can collect a dollar a
| sub from cable?

Because a dollar a sub from cable won't scale to the kinds of channels
we have now. Do you know what "BASIC cable is"?

| They will be marginalized by 8-VSB and hopefully just fade away. My take
| on FCC intentions. The FCC shows no interest in protecting the OTA
| spectrum. Their job as I see it is to marginalize all free OTA spectrum
| with the object of finding a way to legally co-opt current full power
| broadcasters with some form of must carry that is divorced from any
| actual broadcast requirement and then sell off their spectrum, channels
| 2-51. Note the allowance of power line deliver of broadband and the
| allowance of the free use of unused TV spectrum, 2-51 by smart radios.
| Both are hotly contested by broadcasters as interfering with their
| broadcast. Doesn't seem to have any effect on the FCC intentions. The
| FCC has privately written off free OTA spectrum and is in a holding
| pattern waiting for the correct political timing to eliminate it.

BPL is already doomed. It won't be able to keep up. Just because it
_can_ approach other forms of fast internet today doesn't mean it will
be able to do so in the future. Eventually power companies will see
that running fiber over their existing right-of-way is a whole lot
better.

Certaintly the FCC has had its issues. But the FCC has also be lied to
by the BPL equipment makers, and that is now coming out. For example in
the Manassas VA situation, they are starting to make the necessary orders.

| The channel capacity of OTA isn't as great as that of satellite, especially
| when considering high definition. I don't see that as a viable option for
| the number of channels we have, and the number of people wanting them in HD.
|
| But I wouldn't mind a satellite based "Freeview".
|
| They have that to in the UK.

So maybe Sinclair could do this and be first to market with the USA version.

| As to the capacity of OTA spectrum. It is greater than you think. Most
| of what we watch on TV is prerecorded. Doesn't matter when it is
| delivered if it is recorded at the receive site and record storage cost
| are approaching zero. All part of our concept since 1999. If you are
| using all the spectrum available in a given market 24/7 you can more
| than compete with cable or satellite and be more reliable at less cost.
| The cost of maintaining the broadcast spectrum is lower than the gas
| cost of the cable company.

You still have to deliver it to the recorder. The advantage is when there
is 2 or more playback times. But then you might as well allow playback at
any time within the timeframe the program is slotted for. And if such a
system can dynamically replace the commercials with new ones, that makes
the playable time frame even larger.

But that's not OTA TV. It's much better done by satellite and maybe cable
or DSL/fiber.

| So why did the manufacturers choose not to make their receivers upgradable?
|
| Because it would have cost a few pennies more. Because they barely made
| receivers at all. Very half hearted effort still.

So you agree, it is the fault of manufacturers that we don't have decent
products available.

| And why is mobile important to me? So I can watch my favorite soaps in
| high definition while driving?
|
| First DVB-T COFDM was not designed for portable, it was designed for
| good reception in the presence of multipath, the nemesis of OTA analog
| broadcasting from day one. The fact that it can be received mobile or
| portable is a fringe benefit. The point is that COFDM is far better for
| reception. That is why you want it. If you want to watch HD mobile you
| can. You don't have to be driving, you could be a passenger in a car,
| train, boat etc. etc.

Multipath is not much of an issue for OTA analog in most locations. The
only time I have seen multipath issues is in concrete valleys. That means
the few people who live downtown, and those who watch their soaps while
driving.

| | | And broadcasters would love to do just that and the cost to do so would
| | | not be any more than the upgrade to MPEG4 and A-VSB would be.
| |
| | Modulator? PA? power bill?
| |
| | Broadcasters in ALL other countries have faced these and chose COFDM
| | modulations. The power bill is a fiction. No test has shown that there
| | is a difference in the far field with reception at the same power
| | levels. I think that even there COFDM would be easier to receive and
| | receivable by more people than 8-VSB due to multipath than any power
| | differential. The latest I have heard on COFDM is that it now has an
| | advantage over 8-VSB in the lab.
|
| What test was done in the "far field"? I call it "fringe" at 125 miles.
|
| The typical "B" grade for a broadcast station is 60 miles. At 125 miles
| it presents problems of interference for other co-channel broadcast. Far
| field would be at the "B" grade.

125 miles works with analog. It can work with digital, and probably a lot
better, regardless of 8VSB vs. COFDM, as long as the power level is enough.
The tighter spacing of stations only means those in the fringe (125 miles)
need to get a directional antenna, which is already the practice since we
both know rabbit ears don't work at 125 miles.

| If national programming is better sent over satellite, then so be it.
| If OTA dies for that reason, so be it. At least it would be a real reson.
|
| OTA free broadcasting will die because of the modulation and the
| disinterest of broadcasters in supporting decent reception when they can
| make a buck a month per cable subscriber. OTA is kicking but in
| countries with high cable and satellite use because it is free and is
| receivable easily with simple antennas and inexpensive receivers.

COFDM isn't going to change the interest of broadcasters. If they can make
a buck selling to cable, they will want to even with COFDM. 8VSB actually
does work. If the broadcasters want to abandon it to be a cable provider,
that's their business (they should get out of broadcasting, and let others
have those licenses).

| | How are you going to explain why in most other countries OTA will be
| | incredibly successful and be killing satellite and cable?
|
| Because in other countries, they don't have so much of a hunger for 1000 HD
| channels. Most other countries don't allow a few big conglomerates to run
| everything. But they consider that their God-ginve right to do that here.
|
| In the digital age there is no need for 1000 channels of delivery of
| mostly prerecorded content. The Internet will do that. OTA is more than
| adequate to deliver all the real time TV required. And with low cost
| storage it will deliver the equivalent of a 1000 channels when coupled
| with broadband. I don't see how high cost cable and satellite survive in
| the low cost world of broadband and OTA.

We are nowhere near that dream. There are only so many bits available on
a finite set of OTA channels, so you can't get all that content pre-delivered
to the recorders, anyway. If you're doing 2x and 3x repeats like a lot of
the national networks do, then sure, the repeated time frame is suitable for
disk replay. OTA programming has a lot less of that.

| How much HD programming is going to be coming through these channels?
|
| After the auction of channels 52, 53, 56, 57 and 58 you can expect, with
| proper set up to be able to receive all the TV you addiction will stand
| via COFDM based services. Not to cell phones because this spectrum will
| be addressing all mobile and fixed devices. The Qualcomm spectrum being
| the only possible exception. And their spectrum will be just added to
| the mix. That is some player who will have more than one channel will
| take over the Qualcomm space and either convert it to higher bit rate
| content or just continue it as Mediaflow to cell phones. It will not be
| a stand alone service for long. It has to become more universal, that
| is, higher bit rate, more like normal TV, or it will not survive.

The total programming of those auctioned channels, even at just SD, is
not even going to come close to what the satellite providers offer now.
There is far more bandwidth on satellite. Whatever technology can do to
squeeze more out of each Mbps, it can be done on either spectrum.

| After the later auction of channels 2-51 you can expect a lot of free
| OTA COFDM based everything and a radical change in FIOS, cable and
| satellite. They don't survive, everything goes wireless. Fiber, cable
| and satellite are all to expensive to maintain. Wireless rules for
| everything.

If I were to believe all that you say, then that's all the more reason
for me to want OTA to stick with 8VSB so OTA dies out and all these better
services can come along. But I doubt it will involve 2-6 and maybe not
even 7-13.

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|---------------------------------------/----------------------------------|
| Phil Howard KA9WGN (ka9wgn.ham.org) / Do not send to the address below |
| first name lower case at ipal.net / |
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