"In the USA, the companies running DTT are fighting the technology as they believe it will generate unwelcome interference:" ..... a Mistaken Belief borne of Ignorance in Virtualisation Technologies at the Alien Quantum InterFace........... AIResearch and dDevelopment Special Forces.

42 Qummunication beyond Human Comprehension to the Fatima Levels in Venus CodeXXXX. AISeXXXXual Role Reversal Appreciation/Polyamoral Understanding.

Now that would be Special Applications Program which would be Interesting to UnderWrite against Failure and Non-Stellar Performance.

Eve's Shock and Awe Troopers Source Code. The Immaculate Source of Global Operating Devices OmniSentient Power in Controls........ and Priceless 42 Behold for IT is FreeDom in a Matrix at ITs NeXXXXi of Control. A HyperRadioProActive Tom in Heavenly Cat Traps ....... Love's Lovers' Taunting Haunting Chambers 42 BetaTest ITs Turing Spells with their Sublime Supine Sabine Spinning.

Which is a Quantum Leap across the Virtually Real Boundary into AI Quantim Beta BroadBand Spectrum Use........ TEMPEST Chained and In Controls.

Patents Pending should Patents Protection be more than just a Gravy Train, I suppose. :-) An Interesting Business, Patents....especially when they can Fully Justify printing Money for Use rather than Storage.

As you can read, there is more than just digital radio in the spectrum and it is part of digital visual to given added depth to Synched BroadBandCast of Created Virtual Reality and Quantum ControlLed Reality LandScapes with Virtual Countries to Administer Mentored Instruction.

Binary Medicine for All Ills ...... AI MegaMetaVXXXXine.

Which you will surely have to admit, is a pretty bold claim to be Registering but no less Real because of IT.

While it sounds like a great idea, people should note that what looks like "unused" to one person can be "very used" to another who is in a different locale (nearby). In addition, if you have a transmitter that is hopping around, how does the receiver find it?

Using TV channels this way is NOT a very good idea. These "white space" guys should go to a proper unlicensed (sorry US spelling) band like 2.4GHz that ALREADY works.

This is nothing more than fear-mongering on the part of old tech dinosaurs. The people developing this technology are very sensitive to the issue of interference.

Please see <a href="http://www.newamerica.net/files/WhiteSpaceDevicesBackgrounder120607.pdf">this </a> paper for more information.

The "white-space devices" people know that what's holding them back is not technology, but propaganda. If that were not true, why haven't the various regulators (FCC, Ofcom, more in Europe) walled off some territory so that we can practice blasting each other with RF? We have military bases, bombing ranges, swathes of land devoted to training children in the art of war, but strangely enough, no amount of land is designated an RF "free-fire zone".

This tech has been a long time coming, and the broadcasters who are screaming about potential harm to their business model are just going to have to deal with it. They could always just cloud out the white spaces with interference, if this new technology is such a threat. Personally, I think that it scares them to have to share their spectrum with a bunch of anarchists.

Americans, and to a certain extent Europeans, are so used to tuning in to a particular frequency to get their information, that it behooves them do things a different way. Really, what it will mean is the death of the FCC, because the FCC was created to resolve conflicts with frequency sharing and interference. This problem has been solved technologically.

Now, if only politics would catch up.

I guess you either a) work in marketing in this field or b) you just don't have a clue.

The first problem isn't interference, it's working out how to get the transmitter and receiver on the same frequency at the same time. Not so easy.

Second problem is interference - how do you know a channel is free? Is any other user supposed to chuck a carrier out constantly so you don't borrow the channel? And how can a unit decide a channel is free? Anyone who's ever done propagation modelling knows that signals can end up behaving very differently from a pure free space model, and that just because you can't detect another transmitter doesn't mean someone can't detect you.

Oh yes, and if looking for a "designated an RF "free-fire zone"" there are already unlicensed bands. 2.4Ghz is a well known one.

What this system actually sounds like is HF ALE. That does work, and reasonably well, but then again it's not trying to fit in spaces between other systems and it tends to be a single point-to-point negotiated link.

If someone really wants to try this kind of thing, it's best done in a band where it won't break something else eg. TV signals, which are sensitive to interference.

And maybe dealing with a dose of reality; at the moment this just sounds like someone trying to get something for nothing, throwing a fancy name at the concept and hoping they can get away with it. Unfortunately real life is a bit harsh and many ideas don't work well outside the lab. Or even inside the lab if too many questions are asked.

Honestly, it is clear you have not got any clue about radio engineering at all. Your statements, and citing a lobby interest paper for "justification", simply beggars belief!

A statement such as "the FCC was created to resolve conflicts with frequency sharing and interference. This problem has been solved technologically" is so broad and, in most case, simply wrong that the only explanation is you are somehow in the pocket of those aiming to make a fast buck from these cognitive systems.

It is easy to see lots of situations where the current plans will fail to protect existing users, and there has been no coverage of how you retract to operation of any device that is causing problems.

But, hey! that not your problem is it? Some other guy (e.g. television company, theater, etc) can fund the whack-a-mole solution to the problems your equipment has caused. Got to keep your profits up, what?

The problem with the 2.4 GHz band is that it is very small, any very occupied. Wifi and Bluetooth free for all and whoever else cares to join. Seeing that according to some simple measurements, more than 80% of the available spectrum is unused, there is a strong case for some form of freeing up of the radio spectrum.

The current approach to Cognitive Radio, as by the IEEE 802.22 Working group, is to identify an open channel, and then to transmit on that channel for something like two seconds, and then to check that the channel is still empty before continuing to transmit. Also, the sensing requirements are very strict, something on the order of -116dBm with 95% certainty. It is also an infrastructure based standard, allowing for some planning to reduce interference with the local incumbents.

Even though Cognitve Radio faces many obstacles, it is probably one of the most promising technologies for improving radio spectrum usage. We can all only hope that they find solutions to the problems affecting Cognitive Radio, or come up with an alternative solution.

http://www.fcc.gov/sptf/files/SEWGFinalReport_1.pdf

http://www.ieee802.org/22/

... that sees the idiocy of allowing an unlicensed free for all in the guard bands that are there specifically to avoid interference !

As others have said, there is NO reliable way for a device to know that it's signals won't trample over another signal that IT can't see. And it's certainly been known for a long time (almost as long as there's been radio) that you get interference from closely spaced transmissions.

As as the US web site referenced in the article mentions, the interference won't be just a bit of 'snow' in the picture - it will be a complete and intermittent loss of picture and sound. I've experienced such a loss of quality (C5 is poor here at the moment, and under certain weather conditions I get significant dropout). If I found out that I was getting such interference from legally sanctioned devices, then I would be expecting heads to roll from those who sanctioned it.

So the officials and politicians suggesting this is a good thing, just bear in mind that your neck will be on the block when the public find out you were responsible for killing their TV. Over in the US they has a system of Class Action - this I could see as a very worthwhile use for it !

WTF ????????????????????????????????????????????

It's complex man but I take it he thinks there are some patent issues involved.

These systems and their associated spectrum will only become available after the shutdown of analogue TV anyway. DVB-T is far less sensitive to interference, at least if the potentially-interfering signal is designed appropriately. There's no problem with "what if they're not transmitting when you check" in the TV bands (roughly, bands III, IV and V, depending on where you are) since TV transmitters are modulated continuously.

"It's complex man but I take it he thinks there are some patent issues involved." Indeed it is, but any patent issues are for those ambulance chasers who think some bright ideas are worth making difficult to copy for private exclusive use/domination by a back door route. Cricket it aint but that's cut throat business for the intellectually challenged.

Boffins just Do IT for Real, Virtually.

In this issue, I'd like to point out that the first system that was submitted to the FCC (vaguely equivalent to Ofcom) failed miserably. The Microsoft-designed device, backed also by Dell, HP, IBM and Google quite simply failed to leave in-use channels, spamming up clear and in-use channels alike.

Microsoft's claim was that the prototype must have been defective -- well, so what? If a defect causes the unit to start blasting away, interfering with TV channels, that's the very essence of a device that should not be manufactured and shipped out to millions of people... after all, devices do go bad in the field.

In theory, using white space is a great idea. In practice, it's going to really have to be made bulletproof (and failsafe) to be a good idea at all. By failsafe I mean things Including, for instance, detection if the antenna has been damaged that should disable the unit (since in that case it won't detect in-use channels properly.)

Looks like lots of people didn't have R/C cars in their childhood. I remember there were the 27 MHz and 49 MHz variants specifically to allow two kids to race their cars. Why? Because two 27 MHz cars would have interference and do weird things! I remember that using the controller for one car on the other would do funny things like making the car go in reverse with any command (turn left, turn right, and such).

Of course, sometimes you'd find out your neighbor was playing with his car when turning on yours ended up in your own R/C car running full-speed against the wall.

Now imagine this on a larger scale, affecting TV sets.

Are so the age of magic is making its way to the legal paladium.

What with quatum radar, plasma transmitters(to home in and cognize(the first free space electrical device mans ever made), oh and faster jefferson super conducting junctions as to tune the pasma faster.

Um looks like a quantumly accurate (perhaps better) computer that can dominate the radio world from 0.000001 - 9GHz if it wants to.

I wonder if theres any technology that might operate across such a spectrum and that might even make more specific use along such a spectum.

Trouble is i can't THINK what such an electrical device might look like.

Being paranoid was just to wrong for me sicne i only heard a few voices from time to time it's not like anything wrong would be done to me we're all included in the great family right?

Yes mate because so few groups knew to fight it they'll get total control of your minds and cause yet more genocide under rule of the cow all to the plesure of the king of sudi arabi.

They won't get my mind though

just look what hitler did killed the clever ones first.