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Facts on Australia

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March 7, 2005 3:39:24 AM

Archived from groups: alt.video.digital-tv (More info?)

Australia is not abandoning HD because of Impulse noise.

The broadcasters here are required to transmit at all times an SD
version of their analog program and then broadcast 1020hrs a year in
HD. In a 7 MHz channel this provides approx 19 Mbit/s in the default
planning mode (eqvlt to 8VSB) or about 23 Mbit/s in the mode most
broadcasters have adopted (approx 1.5 dB increase in C/N and reduction
in SFN capability).

If a broadcaster wants to provide an EPG and surround sound there just
aint enough bits to do decent SD and HD, and even less if they want to
provide a second program stream. This is the reason some broadcasters
have compromised on 576p rather than 1080i - to get enough bits to do 1
or 2 SD program sin decent resolution, plus an EPG, plus HD with Dolby
AC3 surround sound. Nothing to do with impulse noise or failings of
COFDM.

Bob, as I told you in a post in Dec 2003 Australia never adopted ATSC -
officially or unofficially. We were never in the ATSC camp with a last
minute switch to DVB. If anything we were always likely to adopt DVB
and flirted with ATSC because of HD and surround sound.

Australia assessed both ATSC and DVB-T, in parallel, in laboratory and
field tests, in 1997 and recommended DVB-T with the ATSC Dolby digital
AC-3 audio in 1998. The assessment was conducted by a specialist group
of Australian broadcasters and regulators. see press releases at
http://happy.emu.id.au/lab/new­s/news/rmb114.htm and
http://happy.emu.id.au/lab/new­s/news/factsmr2.htm and engineering
reports at http://happy.emu.id.au/lab/inf­o/digtv/reports.htm.

Ray

More about : facts australia

March 11, 2005 1:21:35 AM

Archived from groups: alt.video.digital-tv (More info?)

John S. Dyson wrote:
> In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
> WDino <nogood@bigpond.com> writes:
> I still chuckle at armchair experts (in Austrailia, with a small
scale
> HDTV deployment) that claim that my 8VSB reception doesn't / cannot
> work with my indoor antenna :-).


John,

I'm still somewhat bemused at US experts who don't believe that over
80% of Australia's 20million people already have access to HD
programming - many with satisfactory reception using indoor antennas.

I agree that there is no reason for the US to change from ATSC but the
arguments about ATSC advantages over DVB-T for wide coverage HD
services quoting Australian services shows a lack of knowledge of
Australia, its population distribution, geography, broadcast
arrangements, ...

Ray
Anonymous
March 11, 2005 5:11:48 AM

Archived from groups: alt.video.digital-tv (More info?)

To add to that provided by Ray:

In practice impulse noise was found to be a problem on the lower VHF TV
channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
Then there is no advantage in using ATSC with respect to any impulse noise.

However DVB-T has advantages over ATSC with regard to multi-path. And that type
of problem, in practice, occurs over all TV channels.

Please note that DVB-T now has included the use of surround sound in its
specifications.

And to emphasise what Ray has said, the use or non-use of HD by a network has
nothing whatever to do with technical limitations of the DVB-T system, nor with
any Government directions.


rayt wrote:
> Australia is not abandoning HD because of Impulse noise.
>
> The broadcasters here are required to transmit at all times an SD
> version of their analog program and then broadcast 1020hrs a year in
> HD. In a 7 MHz channel this provides approx 19 Mbit/s in the default
> planning mode (eqvlt to 8VSB) or about 23 Mbit/s in the mode most
> broadcasters have adopted (approx 1.5 dB increase in C/N and reduction
> in SFN capability).
>
> If a broadcaster wants to provide an EPG and surround sound there just
> aint enough bits to do decent SD and HD, and even less if they want to
> provide a second program stream. This is the reason some broadcasters
> have compromised on 576p rather than 1080i - to get enough bits to do 1
> or 2 SD program sin decent resolution, plus an EPG, plus HD with Dolby
> AC3 surround sound. Nothing to do with impulse noise or failings of
> COFDM.
>
> Bob, as I told you in a post in Dec 2003 Australia never adopted ATSC -
> officially or unofficially. We were never in the ATSC camp with a last
> minute switch to DVB. If anything we were always likely to adopt DVB
> and flirted with ATSC because of HD and surround sound.
>
> Australia assessed both ATSC and DVB-T, in parallel, in laboratory and
> field tests, in 1997 and recommended DVB-T with the ATSC Dolby digital
> AC-3 audio in 1998. The assessment was conducted by a specialist group
> of Australian broadcasters and regulators. see press releases at
> http://happy.emu.id.au/lab/new­s/news/rmb114.htm and
> http://happy.emu.id.au/lab/new­s/news/factsmr2.htm and engineering
> reports at http://happy.emu.id.au/lab/inf­o/digtv/reports.htm.
>
> Ray
>
Related resources
Anonymous
March 11, 2005 5:41:48 AM

Archived from groups: alt.video.digital-tv (More info?)

In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
WDino <nogood@bigpond.com> writes:
> To add to that provided by Ray:
>
> In practice impulse noise was found to be a problem on the lower VHF TV
> channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
> Then there is no advantage in using ATSC with respect to any impulse noise.
>
> However DVB-T has advantages over ATSC with regard to multi-path. And that type
> of problem, in practice, occurs over all TV channels.
>
Actually, you are tending to overblow the problem WRT multipath, and other
impairments seem to be mistaken for multipath. When the other impairments
are mitigated (e.g. overload, serious interference, etc), then the
alleged multipath disappears!!!

So, the 'advantage' of COFDM WRT multipath is much less of an advantage
for fixed, home reception (even with my indoor antenna with ATSC) than
sometimes is implied by those who dont' watch HDTV daily.

More completely, COFDM does have some minimal advantages over 8VSB,
but 8VSB has some minimal advantages over COFDM.

I still chuckle at armchair experts (in Austrailia, with a small scale
HDTV deployment) that claim that my 8VSB reception doesn't / cannot
work with my indoor antenna :-).

On the other hand, the marginal benefit of COFDM in mobile applications
would certainly cause obnoxious parasitic attempts (by people like Bob)
to buy bandwidth from money hungry broadcasters.

So, COFDM's 'advantages' do start appearing in true mobile applications,
where dynamic multipath tends to be much more severe. For HDTV reception,
this is a non-advantage. Note that our own domestic consumer use of
COFDM in the US, XM radio, isn't very reliable at all. So, perhaps
most of COFDM's advantages are specious anyway.

John
Anonymous
March 11, 2005 9:34:18 AM

Archived from groups: alt.video.digital-tv (More info?)

WDino wrote:
> To add to that provided by Ray:
>
> In practice impulse noise was found to be a problem on the lower VHF TV
> channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
> Then there is no advantage in using ATSC with respect to any impulse noise.
>
> However DVB-T has advantages over ATSC with regard to multi-path. And
> that type of problem, in practice, occurs over all TV channels.
>
> Please note that DVB-T now has included the use of surround sound in its
> specifications.
>
> And to emphasise what Ray has said, the use or non-use of HD by a
> network has nothing whatever to do with technical limitations of the
> DVB-T system, nor with any Government directions.
>
>
> rayt wrote:
>
>> Australia is not abandoning HD because of Impulse noise.
>>
>> The broadcasters here are required to transmit at all times an SD
>> version of their analog program and then broadcast 1020hrs a year in
>> HD. In a 7 MHz channel this provides approx 19 Mbit/s in the default
>> planning mode (eqvlt to 8VSB) or about 23 Mbit/s in the mode most
>> broadcasters have adopted (approx 1.5 dB increase in C/N and reduction
>> in SFN capability).
>>
>> If a broadcaster wants to provide an EPG and surround sound there just
>> aint enough bits to do decent SD and HD, and even less if they want to
>> provide a second program stream. This is the reason some broadcasters
>> have compromised on 576p rather than 1080i - to get enough bits to do 1
>> or 2 SD program sin decent resolution, plus an EPG, plus HD with Dolby
>> AC3 surround sound. Nothing to do with impulse noise or failings of
>> COFDM.
>>
>> Bob, as I told you in a post in Dec 2003 Australia never adopted ATSC -
>> officially or unofficially. We were never in the ATSC camp with a last
>> minute switch to DVB. If anything we were always likely to adopt DVB
>> and flirted with ATSC because of HD and surround sound.
>>
>> Australia assessed both ATSC and DVB-T, in parallel, in laboratory and
>> field tests, in 1997 and recommended DVB-T with the ATSC Dolby digital
>> AC-3 audio in 1998. The assessment was conducted by a specialist group
>> of Australian broadcasters and regulators. see press releases at
>> http://happy.emu.id.au/lab/new­s/news/rmb114.htm and
>> http://happy.emu.id.au/lab/new­s/news/factsmr2.htm and engineering
>> reports at http://happy.emu.id.au/lab/inf­o/digtv/reports.htm.
>> Ray
>>

The US has major problems with using the lower VHF channels also.
Especially because of impulse noise problems.

Bob Miller
Anonymous
March 11, 2005 9:43:11 AM

Archived from groups: alt.video.digital-tv (More info?)

John S. Dyson wrote:
> In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
> WDino <nogood@bigpond.com> writes:
>
>>To add to that provided by Ray:
>>
>>In practice impulse noise was found to be a problem on the lower VHF TV
>>channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
>>Then there is no advantage in using ATSC with respect to any impulse noise.
>>
>>However DVB-T has advantages over ATSC with regard to multi-path. And that type
>>of problem, in practice, occurs over all TV channels.
>>
>
> Actually, you are tending to overblow the problem WRT multipath, and other
> impairments seem to be mistaken for multipath. When the other impairments
> are mitigated (e.g. overload, serious interference, etc), then the
> alleged multipath disappears!!!
>
Alleged?? Disappears like magic!! Wow. That is what LG is missing magic
in their 8-VSB receivers or was that something that ATI or Linx has
patented.

Multipath is very real.


> So, the 'advantage' of COFDM WRT multipath is much less of an advantage
> for fixed, home reception (even with my indoor antenna with ATSC) than
> sometimes is implied by those who dont' watch HDTV daily.
>
> More completely, COFDM does have some minimal advantages over 8VSB,
> but 8VSB has some minimal advantages over COFDM.
>
> I still chuckle at armchair experts (in Austrailia, with a small scale
> HDTV deployment) that claim that my 8VSB reception doesn't / cannot
> work with my indoor antenna :-).

Can you mention one OZ person who has stated that? And for the 1000th
time would you stop saying that I have stated that 8-VSB does not work
anywhere. I have stated that 8-VSB can work in an individual
circumstance or even pretty well in a nice flat area or pretty well for
20, 30 or even up to 70% of the population. It does not work well enough
to be our US modulation and it does not work well enough for a business
plan to work for broadcasters.
>
> On the other hand, the marginal benefit of COFDM in mobile applications
> would certainly cause obnoxious parasitic attempts (by people like Bob)
> to buy bandwidth from money hungry broadcasters.

Not me, I do not want their bandwidth for anything like what they think
it is worth. Do not want to be a tenant to broadcasters either.
>
> So, COFDM's 'advantages' do start appearing in true mobile applications,
> where dynamic multipath tends to be much more severe. For HDTV reception,
> this is a non-advantage. Note that our own domestic consumer use of
> COFDM in the US, XM radio, isn't very reliable at all. So, perhaps
> most of COFDM's advantages are specious anyway.

Give it up John. If COFDM works mobile that means that it will also work
much better for fixed locations. Dynamic multipath is caused by a car
going by or a person crossing the room, it doesn't have to happen in
traffic. You want the best modulation for the US and that is COFDM
especially if you want to deliver impeccable HDTV.

Bob Miller
>
> John
>
>
Anonymous
March 12, 2005 3:18:02 PM

Archived from groups: alt.video.digital-tv (More info?)

"John S. Dyson" <toor@iquest.net> wrote in message
news:D 0r0hc$2ugv$2@news.iquest.net...
> In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
> WDino <nogood@bigpond.com> writes:
>> To add to that provided by Ray:
>>
>> In practice impulse noise was found to be a problem on the lower VHF TV
>> channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
>> Then there is no advantage in using ATSC with respect to any impulse
>> noise.
>>
>> However DVB-T has advantages over ATSC with regard to multi-path. And
>> that type
>> of problem, in practice, occurs over all TV channels.
>>
> Actually, you are tending to overblow the problem WRT multipath, and other
> impairments seem to be mistaken for multipath. When the other impairments
> are mitigated (e.g. overload, serious interference, etc), then the
> alleged multipath disappears!!!

I agree that in many broadcast situations multipath can be mitigated - a
decent rooftop aerial pointed at the correct transmitter site has meant only
one of my analogue installations wherever I've lived in Britain has suffered
multipath issues significantly. However that was in East London, where it
was pretty much impossible to get a decent, ghost-free, analogue signal in
the location I was living. Similarly a friend in West London has similar
issues. In the same locations DVB-T delivers a better picture - though of
course I have no way of knowing that the pretty severe multipath I was
viewing on analogue would cause problems for 8VSB.

However my father lives close to the flightpath of Heathrow airport, and has
suffered significant dynamic multipath issues (analoge flutter caused by
reflections from planes). Moving from analogue to DVB-T these completely
disappeared as well. Whether 8VSB would have coped as well, again I don't
know, but it is clear that DVB-T copes better than analogue VSB in
delivering a decent picture (as would be expected with a digital scheme)

[snip]

> So, COFDM's 'advantages' do start appearing in true mobile applications,
> where dynamic multipath tends to be much more severe. For HDTV reception,
> this is a non-advantage. Note that our own domestic consumer use of
> COFDM in the US, XM radio, isn't very reliable at all. So, perhaps
> most of COFDM's advantages are specious anyway.

Isn't XM a mixture of satellite and ground-based repeaters, and what
frequency band is it on? I'd have thought that there were issues other than
modulation scheme that caused the problems. Is it possible that COFDM is
only just workable for XM, where other modulation schemes would fail
completely?

Steve
Anonymous
March 12, 2005 3:18:03 PM

Archived from groups: alt.video.digital-tv (More info?)

Stephen Neal wrote:

>
> However my father lives close to the flightpath of Heathrow airport, and has
> suffered significant dynamic multipath issues (analoge flutter caused by
> reflections from planes). Moving from analogue to DVB-T these completely
> disappeared as well. Whether 8VSB would have coped as well, again I don't
> know,


I live in the flight path of an airport, and we get frequent
disastrous fluttering multipath from some stations, on analog.
The picture sometimes disappears completely, on my digital
TV, though it remains in an extremely bad form on an old
analog TV.

On digital, on the same stations, everything is completely totally
rock solid, never ever a problem, using 8-VSB.

Doug McDonald
Anonymous
March 12, 2005 7:52:48 PM

Archived from groups: alt.video.digital-tv (More info?)

Stephen Neal wrote:
> "John S. Dyson" <toor@iquest.net> wrote in message
> news:D 0r0hc$2ugv$2@news.iquest.net...
>
>>In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
>>WDino <nogood@bigpond.com> writes:
>>
>>>To add to that provided by Ray:
>>>
>>>In practice impulse noise was found to be a problem on the lower VHF TV
>>>channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
>>>Then there is no advantage in using ATSC with respect to any impulse
>>>noise.
>>>
>>>However DVB-T has advantages over ATSC with regard to multi-path. And
>>>that type
>>>of problem, in practice, occurs over all TV channels.
>>>
>>
>>Actually, you are tending to overblow the problem WRT multipath, and other
>>impairments seem to be mistaken for multipath. When the other impairments
>>are mitigated (e.g. overload, serious interference, etc), then the
>>alleged multipath disappears!!!
>
>
> I agree that in many broadcast situations multipath can be mitigated - a
> decent rooftop aerial pointed at the correct transmitter site has meant only
> one of my analogue installations wherever I've lived in Britain has suffered
> multipath issues significantly. However that was in East London, where it
> was pretty much impossible to get a decent, ghost-free, analogue signal in
> the location I was living. Similarly a friend in West London has similar
> issues. In the same locations DVB-T delivers a better picture - though of
> course I have no way of knowing that the pretty severe multipath I was
> viewing on analogue would cause problems for 8VSB.
>
> However my father lives close to the flightpath of Heathrow airport, and has
> suffered significant dynamic multipath issues (analoge flutter caused by
> reflections from planes). Moving from analogue to DVB-T these completely
> disappeared as well. Whether 8VSB would have coped as well, again I don't
> know, but it is clear that DVB-T copes better than analogue VSB in
> delivering a decent picture (as would be expected with a digital scheme)
>
> [snip]
>
>
>>So, COFDM's 'advantages' do start appearing in true mobile applications,
>>where dynamic multipath tends to be much more severe. For HDTV reception,
>>this is a non-advantage. Note that our own domestic consumer use of
>>COFDM in the US, XM radio, isn't very reliable at all. So, perhaps
>>most of COFDM's advantages are specious anyway.
>
>
> Isn't XM a mixture of satellite and ground-based repeaters, and what
> frequency band is it on? I'd have thought that there were issues other than
> modulation scheme that caused the problems. Is it possible that COFDM is
> only just workable for XM, where other modulation schemes would fail
> completely?

Yes, XM is working in the 2.4 GHz spectrum which is not the place to be
for terrestrial broadcasting. Without COFDM there would be no XM or
Sirius at all. They have to build many small cell repeaters to have an
effective terrestrial repeater system. This is not a fault of COFDM but
of the spectrum they are using. Over time maybe XM will build out more
and more terrestrial repeaters till they don't need the satellites ;-)

Those who fault the XM repeater reception do not offer co-ordinates so
that it can be verified if in fact there is a COFDM repeater in the area
however.

Bob Miller
>
> Steve
>
>
Anonymous
March 13, 2005 1:48:22 AM

Archived from groups: alt.video.digital-tv (More info?)

In article <d0umlu$d5u$1$830fa7a5@news.demon.co.uk>,
"Stephen Neal" <stephen.neal@nospam.as-directed.com> writes:
>
> "John S. Dyson" <toor@iquest.net> wrote in message
> news:D 0r0hc$2ugv$2@news.iquest.net...
>> In article <E77Yd.192613$K7.161190@news-server.bigpond.net.au>,
>> WDino <nogood@bigpond.com> writes:
>>> To add to that provided by Ray:
>>>
>>> In practice impulse noise was found to be a problem on the lower VHF TV
>>> channels. Hence DTV in Oz is confined to the higher VHF and UHF channels.
>>> Then there is no advantage in using ATSC with respect to any impulse
>>> noise.
>>>
>>> However DVB-T has advantages over ATSC with regard to multi-path. And
>>> that type
>>> of problem, in practice, occurs over all TV channels.
>>>
>> Actually, you are tending to overblow the problem WRT multipath, and other
>> impairments seem to be mistaken for multipath. When the other impairments
>> are mitigated (e.g. overload, serious interference, etc), then the
>> alleged multipath disappears!!!
>
> I agree that in many broadcast situations multipath can be mitigated - a
> decent rooftop aerial pointed at the correct transmitter site has meant only
> one of my analogue installations wherever I've lived in Britain has suffered
> multipath issues significantly.
>
Well, I agree with your agreeing -- however, I claim that many of the
so called 'multipath' problems in 8VSB reception ARE NOT MULTIPATH. I
wrote above that once some non-multipath problems are mitigated, then
the APPARENT (untrue) multipath goes away!!!

All too often, people with agendas seem to mistake other problems
for multipath. I am NOT claiming that all alleged multipath situations
are untrue, but most of my own reception problems could have been mistaken
for multipath, but WERE NOT MULTIPATH.

John
Anonymous
March 14, 2005 3:39:05 AM

Archived from groups: alt.video.digital-tv (More info?)

Doug McDonald wrote:
> Stephen Neal wrote:
>
>>
>> However my father lives close to the flightpath of Heathrow airport,
>> and has suffered significant dynamic multipath issues (analoge
>> flutter caused by reflections from planes). Moving from analogue to
>> DVB-T these completely disappeared as well. Whether 8VSB would have
>> coped as well, again I don't know,
>
>
> I live in the flight path of an airport, and we get frequent
> disastrous fluttering multipath from some stations, on analog.
> The picture sometimes disappears completely, on my digital
> TV, though it remains in an extremely bad form on an old
> analog TV.
>
> On digital, on the same stations, everything is completely totally
> rock solid, never ever a problem, using 8-VSB.
>

Sounds like both 8VSB and COFDM deliver advantages over analogue for us.

Given that COFDM countries are unlikely to ditch their systems and go 8VSB,
and 8VSB countries are now unlikely to adopt COFDM techniques it is a bit of
a moot point.

However I suspect, ignoring modulation schemes, Europe may benefit from
being later adopters - compared to Aus with DVB-T+MPEG2 HD and the US/Korea
with ATSC 8VSB+MPEG2 HD - by adopting DVB-T with MPEG4 and/or DVB-S2 with
MPEG4 for HD.

Some might argue that this is repeat of the PAL vs NTSC argument - but I'm
too sensible to start that old debate again... (Picture Always Lousy vs
Never Twice the Same Colo(u)r) (And yes I'm happy to admit that this is as
much a 4.43 vs 3.58 and a 7Mhz vs 6Mhz and a dual channel FM vs NICAM
digital audio debate as a PAL vs NTSC encoding one - in UK terms anyway)

Steve
March 14, 2005 11:45:54 AM

Archived from groups: alt.video.digital-tv (More info?)

"Bob Miller" <robmx@earthlink.net> wrote>>>
>
> The US has major problems with using the lower VHF channels also.
> Especially because of impulse noise problems.
>
> Bob Miller


Miller is a failed datacasting (read: COFDM) business entrepreneur in the
U.S.A.

Almost every word he has uttered about broadcasting has been proven to be a
lie.

He's been asked to leave numerous DTV internet forums because of his
_personal_ jihad
against our ATSC/8VSB system.

Please read ANY of his postings with a tremendous truck-load of salt.
Anonymous
March 14, 2005 9:55:47 PM

Archived from groups: alt.video.digital-tv (More info?)

David wrote:
> "Bob Miller" <robmx@earthlink.net> wrote>>>
>
>>The US has major problems with using the lower VHF channels also.
>>Especially because of impulse noise problems.
>>
>>Bob Miller
>
>
>
> Miller is a failed datacasting (read: COFDM) business entrepreneur in the
> U.S.A.
>
> Almost every word he has uttered about broadcasting has been proven to be a
> lie.

Don't forget that bob is a tremendous negative indicator. He has been
wrong 100% of the time when making a prediction on usenet.

> He's been asked to leave numerous DTV internet forums because of his
> _personal_ jihad
> against our ATSC/8VSB system.
>
> Please read ANY of his postings with a tremendous truck-load of salt.

Better not to read them at all.

Matthew

--
Thermodynamics and/or Golf for dummies: There is a game
You can't win
You can't break even
You can't get out of the game
!