Tiny TV could make billions for FCC
It's a seasonal miracle
The CTIA and CES have produced a white paper outlining how to extract 180MHz of TV-broadcast spectrum without impacting TV quality or coverage, and it's worth reading.
The Cellular Telephone Industries Association (CTIA) and Consumer Electronics Association (CES) co-authored the paper (pdf) which proposes replacing centralised TV transmitters with a network of small, low power stations which would work with existing set-top boxes and free up between 100 and 180MHz of spectrum - spectrum which the CTIA's members would love to get their hands on.
Proposals from the CTIA often verge on the hysterical - such as predicting the downfall of American industry if more radio spectrum isn't allocated post haste. Even this one can't help pointing out that only ten per cent of Americans rely (exclusively) on broadcast TV. But after the usual rant, the document sets out a surprisingly reasonable plan for shrinking TV spectrum usage, though a few technical barriers do remain.
Broadcast TV is based around huge transmitters, normally atop massive towers, which pump out enormous signals that can be picked up 40 miles away. Frequencies can be reused, but only for transmitters at least 80 miles apart - actually much further due to variability in signal propagation. So in the USA there are around 1800 towers, which blanket the country with between 15 and 20 6MHz-wide channels (to carry one analogue channel or a digital multiplex) despite the fact that there are 49 slots available.
That disparity is down to the "near-far problem", whereby the strength of signal necessary to reach 40 miles or more, causes the channel to leak into neighbouring channels for users sitting beside the transmitter. That reduces the channels which can be used, and the CTIA reckons it's using a sledgehammer to crack a nut.
The new plan has lots of little transmitters, working on the same frequency to provide the same coverage and with synchronised transmissions. The significant problem here is "ghosting", whereby the TV receives the same signal twice with a tiny time delay between the two based on differing distances to the transmitters. Analogue TV has always had this problem, which literally results in a ghost image appearing slightly offset from the desired picture. But this is generally down to reflected signals bouncing off walls and suchlike, rather than picking up two signals at the same time.
The CTIA argues that modern set-top boxes are so armoured against receiving bounced ghost signals that they can cope with one coming from a different transmitter. Modern boxes accept the strongest signal and are capable of disregarding the others.
That assertion is the weak point, but if the CTIA has its sums right then there's little reason why the system wouldn't work. The group reckons it will cost less than $2bn to built the new transmitter network (based on 15-20 new transmitters for each one currently operating), while it estimates the value of the frequencies released at between $36bn and $65bn. We'd lean towards the lower estimate, but even if it's half that the plan makes economic sense.
Not that access to more spectrum is the only advantage CTIA members would see from the plan. All those new transmitters will need homes, and could easily be bolted onto cellular towers - reducing costs if not providing revenue for the operator. Let's also not forget that that plan would substantially reduce the available White Space which can be used without paying network operators a penny - so it's good news all round.
The technical issues around ghosting need examination, but this proposal certainly merits more attention and not just in America - the same model could equally well apply in the rest of the world too. ®
Nicely presented, but CTIA's proposal is still dog crap.
"The CTIA argues that modern set-top boxes are so armoured against receiving bounced ghost signals that they can cope with one coming from a different transmitter. Modern boxes accept the strongest signal and are capable of disregarding the others.
That assertion is the weak point,..."
Now there's a massive understatement. Having gone through the US conversion to DTV, I can tell you that the biggest (and as yet, un-addressed) problem with the DTV receiving equipment available in the US, is that the current equipment is extremely susceptible to losing sync with the packet stream due to multi-pathed signals.
During the change over to DTV, for a time we had simulcast analog and digital versions of the same broadcast channels back to back. We found that for best DTV reception, you had to use the analog channel to position the antenna so that ghosts (multiple signal paths) were effectively eliminated, and this would also produce the best DTV reception, as a clean single-pathed signal would not confuse that packet clocking logic the way a multi-pathed signal would.
So their contention that multi-pathing is not an issue for DTV reception with current equipment is simply a blatant lie, a fiction to sucker supposedly gullible FCC regulators into doing CTIA"s bidding.
"...but if the CTIA has its sums right then there's little reason why the system wouldn't work. The group reckons it will cost less than $2bn to built the new transmitter network"
I suppose the CTIA will underwrite the installation of this $2bn worth of repeater infrastructure on their towers? Yeah, right.
More likely, these s**tweasels will probably expect either the local broadcasters or the local and/or federal taxpayers to fund their repeater build-out. Then they'll find a way way to charge us all subscription access fee's to their repeater network, by helpfully providing DTV equipment, that "solves" all of those nasty multi-path issues which were so conveniently created by the presence of the CTIA sponsored repeater networks.
Of course, CTIA members would sell such a service in the same way they routinely sell cell phones in the US. The equipment will be provided at low or no cost, under a minimum 2 year contract, with easy payments of "only" $19.95 per month. As with their cell service contracts, early termination fees of $250 or more will apply. (No need to change an existing, lucrative, and proven business model, right?)
Time to do some research and write some letters to the FCC.
I hope not!
First I'll lose the 9 US stations I can receive from across the lake.
The talk about this in Canada includes the key words "where numbers warrant". That is if you don't live in a city too bad (they say "only" 5% of people using over the air TV would be cut off).
I think it's really a step towards NO free over the air TV, everyone has to pay for cable or sat. In Canada most of the Cell phone companies are also into cable or sat TV. No surprise that they would love to dump free TV and give them the bandwidth for cell phones.
Sorry, what's wrong with satellite?
Lots of channels, near endless bandwidth (just put up more satellites like the pile at 19.2E), no need for transmitters all over the place, and fairly immune to weather which is more than can be said for a lot of DTT. And while it might seem expensive to put a satellite into space and maintain it, it would appear to be a more appealing option than to try to roll out decent DTT to everybody - especially those in unpopulated areas - hence the BBC's support of Freesat. One central broadcast source instead of hundreds.