Re: RAI opts for DMB for mobile TV
Boltar
> Italian public broadcaster RAI has opted for the DMB standard instead
> of DVB-H for the development of its mobile television service.
I don't quite get the fuss over "new" mobile TV. I bought a handheld
battery powered LCD casio TV in 1992 which still works and gives a
good picture on its 2 inch screen. Why just because TV is on a mobile
is it a big deal? Is it some novelty value like having a car that can
become a boat?
Anyway , TV on mobiles could well become the WEP of the 21st century
given that handheld TVs didn't exactly set the world alight first time
around - and they didn't cost anything to run other than the cost of
the batteries unlike these new digital services!
B2003
Boltar
> Anyway , TV on mobiles could well become the WEP of the 21st century
That should have read WAP. Bloody TLAs ;)
B2003
DAB sounds worse than FM
> Source : http://www.advanced-television.com/2007/july2_july6.htm#th1
>
> From Branislav Pekic in Rome
>
> Italian public broadcaster RAI has opted for the DMB standard instead
> of DVB-H for the development of its mobile television service.
>
> manages RAI's network infrastructure of the pubcaster - "the decision
> was not only strategic, it was obligatory." He points out that an
> investment of E300 million would have been required to set up a DVB-H
> network covering 85 per cent of the population and capable of bringing
> the signals into homes. The same coverage, indoor included, with DMB
> technology costs E8 million. Ciccotti added that RAI is currently
> capable of covering nearly 40 per cent of the population with DMB at a
> cost which is practically zero.
More lies from the European DAB industry. Then again, what else do you
expect when it has included such famous pathological liars as Simon Nelson,
Quentin Howard and Nicolas Croiset?
--
Steve - www.digitalradiotech.co.uk - Digital Radio News & Info
hwh
They forget that there is a DVB-T infrastrcuture in place. So adding
DVB-H is not as expensive as it looks.
I thought Europe had chosen DVB-H as a standard for mobile TV?
gr, hwh
DAB sounds worse than FM
I've yet to see an honest account of DVB-H costs by a "DAB" broadcaster, so
now that RAI has chosen to use DMB and/or DAB+ they're just the latest in a
long line of broadcasters that make DVB-H out to look far more expensive
than it actually is. The way they do this has been documented at length on
this NG, so I don't intend to get into another boring argument with the
pathological liar Croiset about it - for example, it is a mark of how much
of a pathological liar he is that he even denied that he lost the MP2 vs
AAC+ on DAB argument!
> I thought Europe had chosen DVB-H as a standard for mobile TV?
There's lots of pathological liars still trying to spread DMB, such as
Nicolas Croiset.
Richard Evans
1: Although a DVB-H network would be more expensive to set up, it would
be able to carry far more services than a DAB/DMB network. Therefore the
costs could be shared between a much greater number of broadcasters.
2: Presumably that are looking at using DVB-H on uhf, compared to using
DMB on Band III.
Now I know there are practical considerations here, such as perhaps
there isn't enough Band III spectrum for a DVB-H network right now
(Because DAB/DMB got there first and is hogging it all). However that
doesn't change the fact that they are being selective about the facts,
in order to make DVB-H look far more expensive than DAB/DMB.
Richard E.
Richard Evans
> On 5 Jul, 07:45, Nicolas Croiset <ncroi...@vdldiffusion.com> wrote:
>> Italian public broadcaster RAI has opted for the DMB standard instead
>> of DVB-H for the development of its mobile television service.
>
> I don't quite get the fuss over "new" mobile TV.
street with their eyes fixed on their tiny mobile phone screen.
Richard E.
DAB sounds worse than FM
What's the "DAB RAI" multiplex on here then:
http://www.wohnort.demon.co.uk/DAB/h-t.html#Italy
> they are involved in DVB-T and
> DVB-H and choose T-DMB for mobile television.
http://www.dvb-h-online.com/Services/services-Italy-3Italia.htm
http://www.dvb-h-online.com/Services/services-Italy-tim.htm
http://www.dvb-h-online.com/Services/services-Italy-vodafone.htm
Richard Evans
> On Thu, 05 Jul 2007 10:35:40 GMT, "DAB sounds worse than FM"
> <dab.is@dead> wrote:
>
> DVB-H and choose T-DMB for mobile television.
>
This is probably a short term decision, because for various practical
considerations it is easier at the moment to use DMB. However that
doesn't stop DAB/DMB supporters being selective with the facts in order
to make DMB look like a better system than DVB-H.
Richard E.
DAB sounds worse than FM
I think the main thing they're failing to mention is that it looks like
they're just using an existing transmitter network for the most part:
http://www.wohnort.demon.co.uk/DAB/h-t.html#Italy
DAB sounds worse than FM
> On Thu, 05 Jul 2007 11:15:35 GMT, Richard Evans
> <R.P.Evan...@NTLWorld.com> wrote:
>
>> DAB sounds worse than FM wrote:
>>> Nicolas Croiset wrote:
>>>> Source :
>>>> http://www.advanced-television.com/2007/july2_july6.htm#th1
>>>>
>>>> From Branislav Pekic in Rome
>>>>
>>>> Italian public broadcaster RAI has opted for the DMB standard
>>>> instead of DVB-H for the development of its mobile television
>>>> service.
>>>>
>>>> According to the Stefano Ciccotti, CEO of RaiWay - the company
>>>> which manages RAI's network infrastructure of the pubcaster - "the
>>>> decision was not only strategic, it was obligatory." He points out
>>>> that an investment of E300 million would have been required to set
>>>> up a DVB-H network covering 85 per cent of the population and
>>>> capable of bringing the signals into homes. The same coverage,
>>>> indoor included, with DMB technology costs E8 million. Ciccotti
>>>> added that RAI is currently capable of covering nearly 40 per cent
>>>> of the population with DMB at a cost which is practically zero.
>
>>
>> 1: Although a DVB-H network would be more expensive to set up, it
>> would be able to carry far more services than a DAB/DMB network.
>> Therefore the costs could be shared between a much greater number of
>> broadcasters.
>>
>> 2: Presumably that are looking at using DVB-H on uhf, compared to
>> using DMB on Band III.
>>
>> Now I know there are practical considerations here, such as perhaps
>> there isn't enough Band III spectrum for a DVB-H network right now
>> (Because DAB/DMB got there first and is hogging it all). However that
>> doesn't change the fact that they are being selective about the
>> facts, in order to make DVB-H look far more expensive than DAB/DMB.
>
>
> DVB-H (20 programmes, very optimistic) = 300 / 20 = 15 million Euros
> T-DMB (2 programms) = 8 / 2 = 4 million Euros
>
> Far more expensive is the right term I think.
>
> So ?
So 300 million euros and 8 million euros are obviously incorrect figures.
Richard Evans
> On Thu, 05 Jul 2007 11:15:35 GMT, Richard Evans
> <R.P.Evan...@NTLWorld.com> wrote:
>
>>> Nicolas Croiset wrote:
>>>> Source : http://www.advanced-television.com/2007/july2_july6.htm#th1
>>>>
>>>> From Branislav Pekic in Rome
>>>>
>>>> Italian public broadcaster RAI has opted for the DMB standard instead
>>>> of DVB-H for the development of its mobile television service.
>>>>
>>>> According to the Stefano Ciccotti, CEO of RaiWay - the company which
>>>> manages RAI's network infrastructure of the pubcaster - "the decision
>>>> was not only strategic, it was obligatory." He points out that an
>>>> investment of E300 million would have been required to set up a DVB-H
>>>> network covering 85 per cent of the population and capable of bringing
>>>> the signals into homes. The same coverage, indoor included, with DMB
>>>> technology costs E8 million. Ciccotti added that RAI is currently
>>>> capable of covering nearly 40 per cent of the population with DMB at a
>>>> cost which is practically zero.
>
>>
>> 1: Although a DVB-H network would be more expensive to set up, it would
>> be able to carry far more services than a DAB/DMB network. Therefore the
>> costs could be shared between a much greater number of broadcasters.
>>
>> 2: Presumably that are looking at using DVB-H on uhf, compared to using
>> DMB on Band III.
>>
>> Now I know there are practical considerations here, such as perhaps
>> there isn't enough Band III spectrum for a DVB-H network right now
>> (Because DAB/DMB got there first and is hogging it all). However that
>> doesn't change the fact that they are being selective about the facts,
>> in order to make DVB-H look far more expensive than DAB/DMB.
>
>
> DVB-H (20 programmes, very optimistic) = 300 / 20 = 15 million Euros
> T-DMB (2 programms) = 8 / 2 = 4 million Euros
>
> Far more expensive is the right term I think.
>
> So ?
Is this comparing with DVB-H on uhf or on Band III?
If they can find Band III spectrum for DAB networks then they could have
used it for DVB-H. My point is that this doesn't make DVB-H inherently
more expensive than DMB, it is just the practical considerations that
lead to the choice of DMB in this particular case.
Richard E.
Richard Evans
> On Thu, 05 Jul 2007 11:22:39 GMT, "DAB sounds worse than FM"
> <dab.is@dead> wrote:
>
>> Richard Evans wrote:
>>> Now I know there are practical considerations here, such as perhaps
>>> there isn't enough Band III spectrum for a DVB-H network right now
>>> (Because DAB/DMB got there first and is hogging it all). However that
>>> doesn't change the fact that they are being selective about the facts,
>>> in order to make DVB-H look far more expensive than DAB/DMB.
>>
>> I think the main thing they're failing to mention is that it looks like
>> they're just using an existing transmitter network for the most part:
>>
>> http://www.wohnort.demon.co.uk/DAB/h-t.html#Italy
>
>
> "Ciccotti added that RAI is currently capable of covering nearly 40
> per cent of the population with DMB at a cost which is practically
> zero."
>
that have led to the choice of DMB in this particular case, and that
doesn't mean that DMB in inherently better than DVB-H.
RIchard E.
Boltar
That could be a market that rapidly thins out if said zombies are
walking near busy roads ;)
B2003
Richard Evans
>
> "the decision was not only strategic, it was obligatory." He points
> out that an investment of E300 million would have been required to set
> up a DVB-H network covering 85 per cent of the population and capable
> of bringing the signals into homes. The same coverage, indoor
> RAI is currently capable of covering nearly 40 per cent of the
> population with DMB at a cost which is practically zero.
I did read the full article. However I forgot the small part where they
mentioned the use of existing DAB networks, as my attention was drawn to
the part where they made DVB-H look far more expensive than DMB.
Whether or not this was a deliberate ploy on their part, I don't know.
Richard E.
Richard Evans
>
> Nobody used DVB-H in band III due to impulsive noise problem which is
> too important in this band. There is also a limited number of DVB-T
> transmitters in band III in operation around the world due to that
> problem.
Well it's the first time I've ever heard of this problem in band III.
Perhaps I'll leave it to somebody who knows more about this to confirm
or deny this particular point.
Richard E.
Richard Evans
> On 5 Jul, 12:17, Richard Evans <R.P.Evans.NoS...@NTLWorld.com> wrote:
>> Boltar wrote:
>>> On 5 Jul, 07:45, Nicolas Croiset <ncroi...@vdldiffusion.com> wrote:
>>>> Italian public broadcaster RAI has opted for the DMB standard instead
>>>> of DVB-H for the development of its mobile television service.
>>> I don't quite get the fuss over "new" mobile TV.
>> It's so that they can sell subscriptions to zombies walking down the
>> street with their eyes fixed on their tiny mobile phone screen.
>
> That could be a market that rapidly thins out if said zombies are
> walking near busy roads ;)
Perhaps the idea is to support the life insurance industry ;)
Bill Wright
"DAB sounds worse than FM" <dab.is@dead> wrote in message
news:0Q3ji.13579$_l6....@newsfe6-win.ntli.net...
> Nicolas Croiset wrote:
> More lies from the European DAB industry. Then again, what else do you
> expect when it has included such famous pathological liars as Simon
> Nelson, Quentin Howard and Nicolas Croiset?
Why do you excuse them by saying that their lying is pathological? Why not
say 'remorseless, incorrigible, recidivist, blatant, inexcusable liars?
Liars who liar by their own volition rather than because of an
uncontrollable compulsion.
Bill
DAB sounds worse than FM
> On Thu, 05 Jul 2007 11:19:29 GMT, "DAB sounds worse than FM"
Yawn.
>>> they are involved in DVB-T and
>>> DVB-H and choose T-DMB for mobile television.
>>
>>
>> http://www.dvb-h-online.com/Services/services-Italy-3Italia.htm
>> http://www.dvb-h-online.com/Services/services-Italy-tim.htm
>> http://www.dvb-h-online.com/Services/services-Italy-vodafone.htm
>
>
> Read that : http://www.crit.rai.it/tvmobile/index.html
>
> They also tried DVB-H.
So did these:
http://www.dvb-h-online.com/Services/services-Italy-3Italia.htm
http://www.dvb-h-online.com/Services/services-Italy-tim.htm
http://www.dvb-h-online.com/Services/services-Italy-vodafone.htm
but presumably the difference is that these 3 have nothing to do with the
DAB industry.
DAB sounds worse than FM
> Nicolas Croiset wrote:
>
>>
>> Nobody used DVB-H in band III due to impulsive noise problem which is
>> too important in this band. There is also a limited number of DVB-T
>> transmitters in band III in operation around the world due to that
>> problem.
>
> Well it's the first time I've ever heard of this problem in band III.
He made it up - there is no problem with impulsive interference in Band III.
DAB sounds worse than FM
> On Thu, 05 Jul 2007 11:22:39 GMT, "DAB sounds worse than FM"
> <dab.is@dead> wrote:
>
>> Richard Evans wrote:
>>> there isn't enough Band III spectrum for a DVB-H network right now
>>> (Because DAB/DMB got there first and is hogging it all). However
>>> that doesn't change the fact that they are being selective about
>>> the facts, in order to make DVB-H look far more expensive than
>>> DAB/DMB.
>>
>>
>> I think the main thing they're failing to mention is that it looks
>> like they're just using an existing transmitter network for the most
>> part:
>>
>> http://www.wohnort.demon.co.uk/DAB/h-t.html#Italy
>
>
> per cent of the population with DMB at a cost which is practically
> zero."
Therefore it is obviously dishonest to claim that DVB-H would cost 300m
euros whereas DMB only costs 8m euros, because they're comparing apples with
oranges.
DAB sounds worse than FM
Very true. Actually, I honestly do think Croiset has a psychological problem
when it comes to lying, because he actually seems unable to tell the truth
under any circumstances, but you're absolutely right about Quentin Howard
and Simon Nelson.
hwh
> The infrastructure of DVB-T is not the same as the infrastructure of
> DVB-H due to an essential difference which is the reception antenna.
>
> with DVB-T you use a directional antenna at the roof top.
> For DVB-H itis an integrated antenna.
>
> So the field strength is not the same.
That depends on the implementation. In the Netherlands for example 50%
of the population does not need a rooftop aerial. Several larger cities
already have one or two DVB-T sites close by. Vertical polarization is
standard.
Germany also uses vertical polarization in cities. No problem adding
DVB-H there. As with any new technology, you won't get national coverage
yet, but that is not hardly surprising nor technology dependent.
gr, hwh
Richard Evans
>> Nicolas Croiset wrote:
>>
>>> Nobody used DVB-H in band III due to impulsive noise problem which is
>>> too important in this band. There is also a limited number of DVB-T
>>> transmitters in band III in operation around the world due to that
>>> problem.
>> Well it's the first time I've ever heard of this problem in band III.
>
>
> He made it up - there is no problem with impulsive interference in Band III.
>
>
>
Silk
> More lies from the European DAB industry. Then again, what else do you
> expect when it has included such famous pathological liars as Simon Nelson,
> Quentin Howard and Nicolas Croiset?
Here we go again...
Boltar
Its like an online Punch and Judy show :o)
B2003
Richard Evans
>
> There is a lot of documents about that at ieee and some other
> institutes.
>
A quick Google search found a few links. Whether or not they are
reputable or not I don't know.
I will try and read a bit more about it at some point, partly to see
whether there is actually a difference between uhf and Band III in this
respect, and if so I'm curious to know why. However a combination of
having a lot to do today, plus one of the pages I found causing my web
browser to crash has put me off for the moment.
Richard E.
DAB sounds worse than FM
> you have to move your antenna in your room to receive perfectly the
> DVB-T signal. You can't do that with DVB-H.
>
> RPC 2: RPC for portable outdoor reception or lower coverage quality
> portable indoor reception or mobile reception. Signal strength at
> 650MHz 78dBµV/m.
>
> RPC 3: RPC for higher coverage quality for portable indoor reception.
> Signal strength at 650MHz 88dBµV/m.
>
> For DVB-H RPC3 is not enough. According to ETSI specs, DVB-H needs
> 97dBµV/m.
WARNING: Every time Nicolas Croiset has ever quoted field strength values
for DVB-H he has lied.
DAB sounds worse than FM
> Nicolas Croiset wrote:
>> On Thu, 05 Jul 2007 13:21:31 GMT, Richard Evans
>> <R.P.Evan...@NTLWorld.com> wrote:
>>
>>> DAB sounds worse than FM wrote:
>>>> Richard Evans wrote:
>>>>> Nicolas Croiset wrote:
>>>>>
>>>>>> Nobody used DVB-H in band III due to impulsive noise problem
>>>>>> which is too important in this band. There is also a limited
>>>>>> number of DVB-T transmitters in band III in operation around the
>>>>>> world due to that problem.
>>>>> Well it's the first time I've ever heard of this problem in band
>>>>> III.
>>>>
>>>> He made it up - there is no problem with impulsive interference in
>>>> Band III.
>>> Oh, What a surprise :(
>>
>> please check by your own.
>>
>> There is a lot of documents about that at ieee and some other
>> institutes.
>>
> A quick Google search found a few links. Whether or not they are
> reputable or not I don't know.
Impulsive interference affects 2K mode - as used on Freeview in the UK - but
8K mode is almost immune to it. DVB-H almost always uses 8K.
hwh
> Impulsive interference affects 2K mode - as used on Freeview in the UK - but
> 8K mode is almost immune to it. DVB-H almost always uses 8K.
I think 4k?
gr, hwh
Richard Evans
>
> It is not enough, they use RPC2 (cf GE2006), not RPC3, it means that
> you have to move your antenna in your room to receive perfectly the
> DVB-T signal. You can't do that with DVB-H.
Does this mean that if you're using DVB-H you can not move the antenna? :-/
Richard E.
Richard Evans
>
> Impulsive interference affects 2K mode - as used on Freeview in the UK - but
> 8K mode is almost immune to it. DVB-H almost always uses 8K.
OK, I remember you once saying that 8K is less prone to impulse noise
than 2K. Presumably if they use time interleaving for DVB-H that would
also help a great deal. Do they use time interleaving on DVB-H?
Richard E.
hwh
> It is not enough, they use RPC2 (cf GE2006), not RPC3, it means that
> you have to move your antenna in your room to receive perfectly the
> DVB-T signal. You can't do that with DVB-H.
>
> portable indoor reception or mobile reception. Signal strength at
> 650MHz 78dBµV/m.
>
> RPC 3: RPC for higher coverage quality for portable indoor reception.
> Signal strength at 650MHz 88dBµV/m.
>
> For DVB-H RPC3 is not enough. According to ETSI specs, DVB-H needs
> 97dBµV/m.
If you have:
- A network using 1/4 Guard Interval
- 50% RPC2 to begin with
- Vertical polarization
You are in an extremely good position to add transmitters and/or
increase power if the service becomes a success in areas within the
current service area.
If you have a transmitter servicing a certain area at 88 dB(micro)V/m
you serve an area of roughly 70% that size within 97 dB(micro)V/m. As
several transmitters are in or near the main cities you can start by
reaching a lot of people using the DVB-T layout.
gr, hwh
hwh
Well, you can if you have a hand held device. But in a car you could
have to pull up a bit at traffic lights (just like when listening to
FM). ;-)
gr, hwh
Richard Evans
I'm beginning to see why some people might say that uhf is less prone to
impulse noise than Band III.
First of all DVB-T tends to be received using multi element rooftop
antennas. Such antennas can be set up to be less prone to receiving
impulse noise. In fact when they installed on at my parents house, they
installed it pointing up at an angle for this reason.
With Band-III this would be more difficult to set up, because the
wavelength is longer, hence the aerials would generally need to have
fewer elements and so be less directional. Perhaps this is why DVB-T
apparently isn't used on Band III (or at least a web pages I found via
Google said it isn't).
In my flat, where I have not been able to connect to a rooftop aerial, I
do get blips in reception, despite the overall signal strength being
quite good. This could quite possibly because of impulse noise. So that
would suggest that uhf isn't exactly immune to impulse noise, simply
that higher gain antennas can be used to reduce the problem. In fact I
managed greatly reduce the problem by putting up an 18 element aerial in
my lounge. (It's not exactly aesthetically pleasing, but without it the
blips in reception where too annoying). All this is however irrelevant
to mobile reception, as I can't see many people using large directional
antennas while mobile.
For DVB-H the use of longer symbol periods than 2k, plus hopefully the
use of time interleaving (I hope they use time interleaving), should
greatly reduce the impulse noise problem. This is what they do for
DAB/DMB, and it seems to solve the problem in that case.
Richard E.
DAB sounds worse than FM
> (DVB); DVB-H Implementation Guidelines) is lying.
>
> Page 89 table 11.12 for a location probability of 95% for indoor
> reception you need between 91dbµV/m with a C/N of 2dB to 115dBµV/m for
> a C/N of 26dB on band IV.
>
> I choose a C/N of 8dB and I obtain 97dBµV/m. this value is higher than
> RPC3 defined at GE2006.
The above figures are the same figures that you've lied about on here on
numerous occasions before. You do the same thing every time where you
selectively quote figures from documents that show DVB-H in a very bad light
that makes it look very expensive.
This is very, very old ground, and I don't want to waste my time discussing
this with someone unable to tell the truth.
DAB sounds worse than FM
8K is almost immune to impulsive interference, 4K is slightly less so, 2K
doesn't handle it well, but if you look at the DVB-H services very, very few
use 2K:
http://www.dvb-h-online.com/services.htm
DAB sounds worse than FM
8K doesn't need time interleaving.
DAB sounds worse than FM
2K is affected because the OFDM symbol duration is short so the impulsive
interference can wipe out a significant proportion of a symbol. The symbol
duration for 8K is 4 times longer, which is why it handles it okay.
Richard Evans
>
> If you add a lot of little transmitters near these ones you will have
> a difference higher than 40dB with the main DVB-T transmitter which
> broadcast on an another channel. So you will have interferences. Cf E
> book and IEC 62216-1. This interference should exist potentially
> between 100 and 500 meters around each DVB-H transmitters.
>
When DigitalOne here in the UK added extra fill in transmitters to their
DAB network, they also added transmissions of other multiplexes in the
area, at an ERP of 5 watts. This was presumably to stop the problem of
the relatively high signal strength near their transmitters from wiping
out the other services.
I would have thought that the same approach could be applied to DVB.
Obviously there is the possibility that services on adjacent channels
might be using a short guard interval, not designed for SFN. However
since this added anti interference signal is rather low power, only
covering a very limited area, I can't really see it being to difficult
to get the timing to work, even with a very short guard interval.
Richard E.
hwh
> Richard Evans wrote:
>> DAB sounds worse than FM wrote:
>>
>>>
>>> Impulsive interference affects 2K mode - as used on Freeview in the
>>> UK - but 8K mode is almost immune to it. DVB-H almost always uses 8K.
>>
>> OK, I remember you once saying that 8K is less prone to impulse noise
>> than 2K. Presumably if they use time interleaving for DVB-H that would
>> also help a great deal. Do they use time interleaving on DVB-H?
>>
>> Richard E.
>
> I'm beginning to see why some people might say that uhf is less prone to
> impulse noise than Band III.
>
> First of all DVB-T tends to be received using multi element rooftop
> antennas. Such antennas can be set up to be less prone to receiving
> impulse noise. In fact when they installed on at my parents house, they
> installed it pointing up at an angle for this reason.
In the UK this would seem the standard method.
> With Band-III this would be more difficult to set up, because the
> wavelength is longer, hence the aerials would generally need to have
> fewer elements and so be less directional. Perhaps this is why DVB-T
> apparently isn't used on Band III (or at least a web pages I found via
> Google said it isn't).
DVB-T is used on Band III in Germany. TV has been used on Band III in
many coutries during the analog days.
gr, hwh
hwh
> Not exactly.
>
> - the path loss attenuation is not linear, cf curves in ITU-R P.1546.
>
> - You must not have in the border of the allotment more signal
> strength than the one defined by the RPC. If you decide to change the
> RPC of your allotment, it means that you must plan once again
> everything like it was done at GE2006.
Yes, there are complications near allotment borders.
> But effectively inside a DVB-T allotment you can provide a DVB-H
> service in a reduced area. But you will be unable to have contiguous
> area between allotments.
At least not at higher levels than agreed upon. But these allocations
seem to be fluid in some respects, especially if the allotment is not
adjacent to another countries' one.
> The last problem is the difference of field strength between DVB-T
> signal and DVB-H signal. Receivers are unable to work correctly if
> there a level difference between transmitters higher than 27 dB to
> 40dB.
Yes, all radio systems suffer from this problem, including DMB and FM.
> If you add a lot of little transmitters near these ones you will have
> a difference higher than 40dB with the main DVB-T transmitter which
> broadcast on an another channel. So you will have interferences. Cf E
> book and IEC 62216-1. This interference should exist potentially
> between 100 and 500 meters around each DVB-H transmitters.
Yes, but if the frequency separation is considerable the chances of
interference are small. Example: 45% of the Netherlands population is in
an allocation where channels 24, 27, 49, 57, 61 and 64 can be used.
If channel 49 would be stronger than the others, there would be little
chance of blanking other multiplexes. Of course careful planning is needed.
gr, hwh
Richard Evans
> problem exist.
>
> For example in Italy we speak about 1000 DVB-H transmitters. You will
> not add a DVB-T gap filler on each DVB-H transmitter site, but even if
> it 20%, it means 200 transmitter sites where theproblem exist and if
> there is 6 DVB-T multiplexes in the area, it means 6 gap fillers * 200
> = 1200 gap fillers to install. The cost is not 0.
>
> Bye.
The cost would not be zero. However we are talking about transmitter
power that is right down into single figures. Surely that would only be
a small proportion of the overall cost of the DVB-H fill in stations
themselves.
Also at such a low ERP all the anti interference DVB-T signals required
could be fed into the same antenna, which wouldn't need to be anything
more complicated than a simple dipole.
Another approach might be to feed the signals through the same antenna
as the DVB-H fill in transmission. However that would presumably require
quite a good filter network, which I assume would work out more
expensive than just adding a simple dipole for the extra
ant-interference signals.
Richard E.
Richard Evans
>
> DVB-T is used on Band III in Germany. TV has been used on Band III in
> many coutries during the analog days.
So it would seem that the extra impulse interference problem on Band-III
(if it actually exists) is not exactly un-solvable.
Richard E.
hwh
> Another approach might be to feed the signals through the same antenna
> as the DVB-H fill in transmission. However that would presumably require
> quite a good filter network, which I assume would work out more
> expensive than just adding a simple dipole for the extra
> ant-interference signals.
Exactly. A small aerial will do to serve the few hundred yards that need
to be covered. In, say, a five transmitter network, the filtering
network used to connect the five transmitters to the aerial is a
significant part of the total cost of the installation.
gr, hwh
hwh
> hwh <iime...@hotmail.com.nospam> wrote :
>
>> Richard Evans wrote:
>
>>> With Band-III this would be more difficult to set up, because the
>>> wavelength is longer, hence the aerials would generally need to have
>>> fewer elements and so be less directional. Perhaps this is why DVB-T
>>> apparently isn't used on Band III (or at least a web pages I found via
>>> Google said it isn't).
>> DVB-T is used on Band III in Germany. TV has been used on Band III in
>> many coutries during the analog days.
>>
>
> a lot of complaints in the reception side.
I think you mean Band I. It is notorious for problems with sporadic-E
and the like. Use of that band for broadcasting will be discontinued for
now. At the RRC-06 allocations have been made to include band III blocks
that can be used for DVB or DMB, whatever the authorities prefer.
This means that that the band is obviously suitable for both
transmission methods.
gr, hwh
Richard Evans
Actually I wasn't talking about using a filter network to combine all
the low power anti interference signals. At power levels in single
figures, couldn't all the signals simply be fed to the same RF
amplifier, which would then be connected to one single aerial.
What I was talking about is whether or not it was worth combining all
these low power transmissions, on the same antenna as the DVB-H gap
filler transmitter, which would presumably in in the region of 10s or
100s of watts. I suspect that that would not be worth doing.
Richard E.
Richard Evans
> Richard Evans <R.P.Evan...@NTLWorld.com> wrote :
>>
>> Also at such a low ERP all the anti interference DVB-T signals required
>> could be fed into the same antenna, which wouldn't need to be anything
>> more complicated than a simple dipole.
>
> Except if you are in adjacent channels.
So are you saying that even at such low power levels, the signals can't
be fed through the same antenna, just because they are on adjacent
channels. I would have thought that at such low power levels the signals
could actually be fed through the same RF-Amp, and then to one single
antenna.
Even if this is not possible, surely it wouldn't cost a fortune to
install a few simple uhf dipoles.
>
>> Another approach might be to feed the signals through the same antenna
>> as the DVB-H fill in transmission. However that would presumably require
>> quite a good filter network, which I assume would work out more
>> expensive than just adding a simple dipole for the extra
>> ant-interference signals.
>>
>
> It creates an extra cost for the DVB-H network without providing any
> money back...
But it would make it possible to set up DVB-H gap fillers in places
where it would otherwise not be allowed for interference reasons. That
could be enough of an incentive to cover some extra cost.
>
> This extra cost is far away from zero. each gap filler cost around
> 10000/15000 euros.
I presume that is the over all cost of the gap filler with an output of
10s or 100s of watts. I'm talking about the extra cost of extra
transmission in with power levels in single figures.
Surely using transmission powers in single figures is a lot less than
doing it for 10s or 100s of watts.
>
> Then you must add the extra maintenance cost of these equipements.
Surely maintenance the cost of such low power transmitters is a lot
lower than for the relatively much higher power DVB-H gap filler
transmitter.
Richard E.
Rayzor
"Boltar" <bolta...@yahoo.co.uk> wrote in message
news:1183642708.5...@c77g2000hse.googlegroups.com...>> > More lies from the European DAB industry. Then again, what else do you
>> > expect when it has included such famous pathological liars as Simon
>> > Nelson,
>> > Quentin Howard and Nicolas Croiset?
>>
>> Here we go again...
>
> Its like an online Punch and Judy show :o)
>
> B2003
He never gives up ranting every one a liar but him.
>
Bill Wright
"DAB sounds worse than FM" <dab.is@dead> wrote in message
news:Uj5ji.9528$nE2....@newsfe3-win.ntli.net...
> Richard Evans wrote:
>> Nicolas Croiset wrote:
>>
>>>
>>> Nobody used DVB-H in band III due to impulsive noise problem which is
>>> too important in this band. There is also a limited number of DVB-T
>>> transmitters in band III in operation around the world due to that
>>> problem.
>>
>> Well it's the first time I've ever heard of this problem in band III.
>
>
> He made it up - there is no problem with impulsive interference in Band
> III.
Band III TV suffers more from impulse interference than UHF, but less than
Band I.
Bill
Frans
<dab.is@dead> wrote:
>Nicolas Croiset wrote:
>> Source : http://www.advanced-television.com/2007/july2_july6.htm#th1
>>
>> From Branislav Pekic in Rome
>>
>> Italian public broadcaster RAI has opted for the DMB standard instead
>> of DVB-H for the development of its mobile television service.
>>
>> According to the Stefano Ciccotti, CEO of RaiWay - the company which
>> manages RAI's network infrastructure of the pubcaster - "the decision
>> was not only strategic, it was obligatory." He points out that an
>> investment of E300 million would have been required to set up a DVB-H
>> network covering 85 per cent of the population and capable of bringing
>> the signals into homes. The same coverage, indoor included, with DMB
>> technology costs E8 million. Ciccotti added that RAI is currently
>> capable of covering nearly 40 per cent of the population with DMB at a
>> cost which is practically zero.
>
>
>More lies from the European DAB industry. Then again, what else do you
>expect when it has included such famous pathological liars as Simon Nelson,
>Quentin Howard and Nicolas Croiset?
I know the RAI was planning to use DMB for mobile TV, so I'm not
surprised by this announcement. Not all countries are willing to free
a lot of spectrum to allow DVB-H to be introduced. For them DVB-T and
HD TV have priority, while a lot of spectrum assigned to DAB is not
used
Frans
Richard L
Richard Evans <R.P.Evan...@NTLWorld.com> wrote:
> Nicolas Croiset wrote:
> > Then you must add the extra maintenance cost of these equipements.
>
> Surely maintenance the cost of such low power transmitters is a lot
> lower than for the relatively much higher power DVB-H gap filler
> transmitter.
But it means a great many more places that you have to drive the Land
Rover to. So you'll also need more engineers to get the work done. And
of course there's the extra site rental to pay.
--
Richard L.
DAB sounds worse than FM
He said:
"Nobody used DVB-H in band III due to impulsive noise problem which is too
important in this band"
which is a complete lie. The truth is that there is no problem with
impulsive interference no matter which band is used if 8K mode is used, and
DVB-H virtually always uses 8K mode, so he simply made up what he said,
because it's against DVB-H, and Croiset is a pathological liar who is
against DVB-H because he works for a company that sells DMB equipment and he
stands to gain financially the more successful the company he works for
becomes.
You can see why there is no problem with impulsive intereference when using
8K mode by looking at Figure 7 on page 8 of this:
http://www.ebu.ch/en/technical/trev/trev_301-dvb-h.pdf
It also shows why DVB-T in the UK does have problems with impulsive
interference, because we're using 2K mode.
DAB sounds worse than FM
> because practicaly it is not working.
How do you manage it? In just 19 words you managed to squeeze in both a
complete lie and display your utter technical incompetence. I have to hand
it to you, you are at least efficient.
hwh
>> Try taking any radio to a high power broadcast site, and you will find its
>> front end doesn't perform very well, when trying to listen to a service
>> not broadcast from that site.
>>
>
> yes this problem exist in all cases even in analog. It is well known
> when you are near a transmitter site.
>
> the bigest differnce is the number of transmitters and their
> localisation. As I said before when you have DVB-H you must create cells
> in the town for indoor reception so it means in the town you will have
> this problem at each cell.
Except when you already have in town transmission sites. This would not
include most of the UK though.
gr, hwh