[xtraterrestrial]

On the 60th birthday of BBC Kingswood Warren, engineers from BBC Research & Innovation succeeded in demonstrating a working real-time demodulator capable of receiving signals compliant to the DVB-T2 standard for the very first time.

Following the approval of the standard by the DVB on 26 June and then the successful test transmissions from Guildford on 27 June, the achievement – on Friday 29 August – is another significant milestone in the delivery of HD over Freeview.

This is the first time anywhere in the world that a live end-to-end DVB-T2 chain has been demonstrated.

http://www.bbc.co.uk/pressoffice/pre...er/01/hd.shtml

[Pixelz]

Very impressive work by R&D. Maybe just in time too, as I noticed the BBC exchanged contracts on Kingswood Warren this week.

I'm wondering if the Guildford trial will be extended to a main transmitter before analogue switch-off. It would be great to receive terrestrial HD in London before 2012 for example (assuming DVB-T2 tuner hardware is available next year).

I still miss the DVB-T HD trials from 2006/7.

[beardedwonder]

The demonstration consists of:

A 36 Mbit/sec multiplex containing three high definition programmes each coded at 11 Mbit/sec with the latest MPEG-4 encoders.

So BBCHD, ITVHD and C4HD?

[Nightdeamon]

Originally Posted by Pixelz

Very impressive work by R&D. Maybe just in time too, as I noticed the BBC exchanged contracts on Kingswood Warren this week.

I'm wondering if the Guildford trial will be extended to a main transmitter before analogue switch-off. It would be great to receive terrestrial HD in London before 2012 for example (assuming DVB-T2 tuner hardware is available next year).

I still miss the DVB-T HD trials from 2006/7.

Ofcom did say they wanted to identify a frequency to enable them to broadcast in london before 2012.

[ps68060]

Isn't the London analogue switch off the last one and scheduled for 2012 or has that changed ? I thought that was the reason for slow rollout of HD.

It's probably all changed since I last looked.

[tvmad-alan]

Great news that we are going to have HD channels on Freeview, BUT there is no news to how many HD channels we should have after the digital switch over.

With space we are paying for on the transmitters with the digital switch over, are we going to loose it all to other uses so that Television by aerial will be come the poor only system as people that can pay will have satellite, broadband and if there have cable in there area.

We need to have know that all the boxes and IDTV that we are all going to have to re-buy are going to give not only four HD channels but 100's of SD channels to keep up with FreeSAT and other platforms and give us all a very good reason to buy into Freeview HD.

SO OFCOM needs to tell the government that ALL space should be given over to freeview TV to give all a full multi channel HD service with 100's of SD channels.

We are paying for this digital switch over by BBC and buying IDTV's & Boxes with our own money.

SO we must be given a full multi HD & SD platform by Transmitters.

[beardedwonder]

Originally Posted by tvmad-alan

SO we must be given a full multi HD & SD platform by Transmitters.

Too late, way too late. Anyway there'll be 3 HD channels by the looks of things. I'll be happy with that seeing as one of them could stay FTV on satellite for a while. The best part is you'll be able to watch HD with a set-top aerial and box. Brilliant!

[callum9999]

I know its never going to happen because of money issues, but how many HD or SD digital channels would fit in the space left behind by analouge tv using DVB-T2?

[tvmad-alan]

Hi

We were told that about 7 to 14 muxes could made with the digital switch over.

Which should have given us about another 100 more channels.

But with our TV space being sold to other uses, we will be lucky to have any new channels.

Also we should have not only 3 HD channels on Freeview but many.

[daveyfs]

Problem is, where's the HD content to put on lots of channels? In the future, there will be lots of HD content, but at the moment, 3 HD channels is realistic and proportionate to the amount of programming being produced in HD at present.

[chrisy]

Originally Posted by tvmad-alan

We were told that about 7 to 14 muxes could made with the digital switch over.

Ofcom always said anywhere from 0 to 2 muxes could be created. Two is what they went for at GE-06, and two is what they got. Unfortunately they want these to be auctioned off for any use rather than restricting them to DTT, so "0-2" is precisely what we will get for DTT and we won't know until the auction. There might be some other localised muxes in interleaved spectrum too.

[tvmad-alan]

Originally Posted by chrisy

Ofcom always said anywhere from 0 to 2 muxes could be created. Two is what they went for at GE-06, and two is what they got. Unfortunately they want these to be auctioned off for any use rather than restricting them to DTT, so "0-2" is precisely what we will get for DTT and we won't know until the auction. There might be some other localised muxes in interleaved spectrum too.

Well there are four to five anlogue channels going. ( BBC1 BBC2 ITV1 CH4 and FIVE )
That is four or five muxes which could give us 6 to 8 full 24 hour channels each. = 32 or 40

So each free new mux could hold 1 hd and 3 sd channels for freeview.

[reslfj]

Originally Posted by callum9999

I know its never going to happen because of money issues, but how many HD or SD digital channels would fit in the space left behind by analouge tv using DVB-T2?

Depends a lot on how the channels are used.

If all 6 multiplexes were converted to DVB-T2 the capacity would be 6x3 = 18 HD channels now and likely 6x4 = 24 HD channels by 2012/13.

The MPEG-4 bit-rate that Boxer will use for SD is 2 Mbps (note: after stat-mux gain). A UK DVB-T2 multiplex will have a capacity of 15+ SD channels - with 2009 MPEG-4 tech.

In the UK, where MFN is (still ?) used, one '70% of households' multiplex can be allocated using the DTT channels (21-30,41-60). This would add 3 or 4 extra HD channels. (see Ofcom consultation on Interleaved spectrum)

In some parts of th UK - like Scotland - there could be even more multiplexes, while in SE England, Wales and NI it will be difficult.

It seems that the 'high-value' part of the analogue spectrum - i.e. the most (only) useful spectrum for mobile broadband/ 4G phones - will be channel 60-69 (currently in the UK only channel 63-68). The channels 31-37+39,40 will not fit into the spectrum to be used internationally and special UK mobile-devices (broadband/4G-phones) may not be developed (UK will be a niche market).

This may allow DTT broadcasters to acquire 6-7 channels - say ch31-37 (+- ch36) and that should ? be enough for one MFN multiplex with high coverage (90% ir higher).
Take a look at the responses from BT,T-Mobile, Vodafone, Wimax and a many more to this Ofcom consultation Cleared award

BUT

if DVB-T2 SFNs' are used from the existing main transmitters, then one channel with one multiplex could cover UK-wide. The capacity of each DVB-T2 SFN multiplex would be between 32 and 33.5 Mbps (-6 and 11%) and not the 36 Mbps quoted by the BBC - but still enough for 3/4 HD channels.

Now, all channels cannot be used, as there must be an equal split at the international borders. A UK-wide SFN is not fit for local/regional programming/advertising either.

An equal split between NL, BE, FR and England would as a first approximation give 1/4 of the channels to each country or Ch21-60 / 4 = about 10 for the UK.
With directional restrictions on the power levels, at sites like Dover, it may be possible for the UK to get a few more - say a total of 12-13 channels.

Now the calculation could look like this:

10-13x4 HD channels = 40+ HD channels and some SD channels.

Note that the international UHF spectrum plan (GE06) is from 2006 - and the UK got all it asked for then. It took years to agree and includes Russia from Vladivostok, Iran, Africa and our part of Europe. It is NOT easy to change and can most surely not be changed anytime soon.

Note also that each new multiplex will require extra transmitters (but no new masts and hopefully no new TX antennas) and wideband aerials will likely be required.
These extra multiplexes will cost money to install and operate - and money seems in short supply with broadcasters - but you know that.

Lars

[reslfj]

Originally Posted by tvmad-alan

Well there are four to five analogue channels going. ( BBC1 BBC2 ITV1 CH4 and FIVE )
That is four or five muxes which could give us 6 to 8 full 24 hour channels each. = 32 or 40

So each free new mux could hold 1 hd and 3 sd channels for freeview.

This is very WRONG - All the old Stockholm 1961 (analogue) channels are not protected after 2012 (2015 in a few countries). The Stockholm agreement has been replaced by the Geneva 2006 (GE06) agreement.

Most of the channels currently used for analogue TV, has been included for digital use in the GE06 plan for the UK.
At DSO these channels are no longer part of the old Stockholm agreement, but of the new GE06 agreement,

The UK could not get more 'high-power' UHF spectrum than that needed for 8 'levels' in Geneva. Most other countries only got 7 UHF 'layers' and 1 VHF layer for DTT.

If you look at the Ofcom plan for DSO (at the main 80/81 sites) you will see that many of the analogue channels, but not all, are reused for post DSO DTT.
You can't use the same high-power channels more than once at the same location.

The channels currently used for DTT are very restricted in direction and power level. These are part of what Ofcom calls 'Interleaved spectrum' and post DSO they will likely be used for local DTT - maybe with a lower bit-rate (like now with the 16QAM or with even lower bit-rates)

Lars

PS! There are uses of some of the UHF spectrum - other than DTT - that very likely are of much more value to society - e.g. UK-wide broadband.

[sl90]

Personally i think mobile broadband would be by far the best option. Broadband anywhere anytime for everyone, and if given enough bandwidth HD streaming over it aswell, best of both worlds.

[reslfj]

Originally Posted by sl90

Personally i think mobile broadband would be by far the best option. Broadband anywhere anytime for everyone, and if given enough bandwidth HD streaming over it aswell, best of both worlds.

No - it is not for pleasure - its for doing more useful things. Mobile broadband can never match broadcast for HDTV.

Mobile broadband is needed to bridge the 'digital divide' between those that can and those that cannot use digital communication for technical reasons.

The UHF frequencies will allow a more universal coverage for an acceptable cost to society.

Lars

[hdfan]

BBC Research and Innovation, turned 60-years-old last Friday, and to celebrate received the world's first end-to-end HD broadcast via DVB-T2, the updated terrestrial broadcast system.

DVB-T2 is widely expected to be used after the analogue switch-off, because it offers a more efficient use of the spectrum than the current DVB-T standard, which is used across Europe. The new system would co-exist with the existing infrastructure and hopefully provide HD to people who don't have services from Sky or Virgin. The BBC has already conducted similar trials, but this one is different because it actually contained video, rather than just being a transmitter test.

The test broadcast consisted of three HD programmes, each encoded using MPEG-4 and each having an 11Mbps data rate. These were multiplexed together and fed into a DVB-T2 modulator developed by the boffins at the BBC. The signal was then sent via the Guildford transmitter -- often used for trials because of its proximity to R&I's headquarters at Kingswood Warren. After being transmitted, the receiving hardware demodulates the signal and produces a transport stream containing the three programmes, which can be decoded by an MPEG-4 decoder.

All of this birthday excitement means we could be on our way to HD on Freeview. It's expected that areas where analogue has already been switched off will be first to receive HD over-the-air -- good news if you live in Wales, not so good for Londoners.

[beardedwonder]

It's possible, and this is just a guess. That they could use the frequency used for the Crystal Palace test to show HD in London for the 2012 Olympics. I have absolutely no information on whether they will/could but it seems, to me, that this could be an option come 2012.

[tvmad-alan]

Mobile broadband will be a waste of time.
wifi and others are for the few that can buy a lap top is fine, but TV is for all and most can buy an TV or have one, so the spare space should be for TV only.

there are many new systems to bring broadband to all other then using TV transmitters.

[reslfj]

Originally Posted by tvmad-alan

Mobile broadband will be a waste of time.
wifi and others are for the few that can buy a lap top is fine, but TV is for all and most can buy an TV or have one, so the spare space should be for TV only.

there are many new systems to bring broadband to all other then using TV transmitters.

You live in another world - at the time of steam engines . We cannot turn time back - we have to live in the present and look forward.

Mobile broadband is not for anything 'funny', its needed for a modern society to function. Its a cost and energy efficient way to do many things.
UHF broadband is very needed to keep rural areas populated in the future.

We can not and will not compete on the cost of labour - we MUST be smarter and we MUST engage as many of our citizens as we possible can in being active and productive.

Access to the Internet is as important tomorrow as the the postman used to be.

Lars

[nwhitfield]

Frankly, I for one can't see the benefit of 100s of channels on DTT. Have you looked at what's on most of the 100s available on satellite?

Given that the costs of broadcasting terrestrially will always be higher than satellite, lots of the smaller outfits that run small channels on satellite won't be able to afford DTT, even if the capacity were there.

You could probably think of maybe 20 or so channels that might be worthwhile additions with quality, original programming. But most of those are not free, and unlikely to become so.

A little extra capacity for TV would be welcome, including more HD, but not 100s of channels. There's enough rubbish as it is.

And while I don't particularly like the made free market rush to auction everything off (and I remain very sceptical about the likelihood of mobile networks buying up UK-only spectrum), wireless broadband is going to be pretty reasonable use of at least some spectrum.

When I visit my mother (not even five miles outside Winchester, though admittedly a couple of hundred yards from the edge of the village), I struggle to get even a GSM signal on some networks, and dialup on her phone line seldom manages more than 14.4kbps.

That's shockingly bad - and in a prosperous part of the south east too.

UHF has pretty good penetration and distance, and it strikes me that it's going to be one of the more cost effective ways of expanding the UK's digital infrastructure, especially to those who are a long way from the exchanges that serve them, and who may otherwise never get decent service.

[planetsedna]

Does anybody know which channel the test was broadcast on from Guildford? It wasn't channel 64 by any chance?

[Pixelz]

Originally Posted by beardedwonder

It's possible, and this is just a guess. That they could use the frequency used for the Crystal Palace test to show HD in London for the 2012 Olympics. I have absolutely no information on whether they will/could but it seems, to me, that this could be an option come 2012.

By 2012 won't analogue be switched off in London anyway?

I was hoping for a preview of DVB-T2 on UHF31 from Crystal Palace next year. But maybe I'm just an imaptient optimist.

[reslfj]

Originally Posted by Pixelz

I was hoping for a preview of DVB-T2 on UHF31 from Crystal Palace next year. But maybe I'm just an imaptient optimist.

You are - 2010 - says Ofcom - for 3.7 million households in London.

Lars

[Ray Cathode]

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