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White Spaces Test "Rigged," Says Google Co-Founder Page
Davide Marney writes "As reported by the Washington Post, Google co-founder Larry Page claims that an FCC field test of white space wireless devices was 'rigged' to make the test device fail to detect wireless microphone broadcasts. A Google spokesman explained later that testers had hidden the wireless microphones within the same frequency as local television stations, preventing the test device from detecting them."
I'm usually a huge fan of google, but in this case, I'm on the side of the entertainment industry because I work in it and already with digital television vs analog we're gonna have a harder time finding open frequencies (and some events have been known to have 40-80 or maybe even more wireless microphones).
There is no such thing as "hiding the wireless microphone frequencies in local tv stations" that is where they live. The problem is the FCC hasn't given us our own frequencies to play with so we have to work around and in the TV channels.
Here's the summary:
There's unused radio spectrum (called "white space") between the TV channels that are designed to give the stations protection. Google (and others) claim that small radio devices can transmit on those frequencies and not harm the TV signals, TV stations of course fearful of anything that might cost them viewers disputed that.
So the FCC set up a field test of a Google device and other devices to see if everything work right. The result of that test was a "fail" for Google's side... but the news is that Google is claiming the wireless microphone channel being tested equated to a local TV broadcasting channel, and therefore was unfair.
It's hard to test these things without the FCC's help... you need to set up a scale model of TV station signals, and that requires an FCC license to do.
Summary for non-engineers:
Google (among others) want to use the newly freed analog TV frequencies to provide long range wireless internet.
Short range RF microphones i.e. wireless stage mics that aren't using IR currently operate in this area as well. current analog TV doesn't interfere, I'll spare details.
Some claim the wireless internet system that has been devised will interfere with these microphones. Google group says they won't because the devices are capable of detecting a microphone transmitting and work around the issue (change freq).
FCC setup a test, device failed to avoid microphones frequencies thus, knocking it out of commission and failing the test.
Google chap claims the testers had the mic transmitting on a frequency used by the local TV channel and this transmitter was so strong that the system could not detect the microphone because it was effectively masked.
Google chap says this was done on purpose.
The end.
that's exactly how wireless microphones are deployed in the field.
In heavily saturated markets, the wireless mic frequency may sit between a TV video signal and the same channel's audio signal.
At least until things go all digital, then audio and video are muxed into one square wave leaving no room to stick a mic signal. This exasperates the dilemma facing wireless mic operators.
And yes that little PDA can easily wreak havoc on a Broadway show, NFL broadcast or any other production. That's why we regulate the spectrum...devices operating on the same frequency will interfere.
FTFA (hiliting mine) "The FCC's wireless microphone field tests were carefully planned and thoroughly executed based on sound engineering science and real-world operating scenarios. These tests were open to the public, and those who choose to discount the results -- which have not yet been published -- had every option to be present and to witness them for themselves."
Ya gotta learn how to play the game, this is gov't after all guys and apparently you didnt lobby quite enough for this.
The white space between channels can be used by auto-tuning software to determine where the channels are by detecting energy levels. Fill the white space up and this sort of auto-tuning cannot work. Modern digital tuners probably don't need this, but older, cheaper designs probably do.
Engineering is the art of compromise.
FAIL!
There will be no full power analog TV broadcasters, but the transition date of 2/17 does not apply to -LP, -CA and translators.
I am the Game-Day frequency coordinator for a major-league sports team (contractor to the league). Some of my colleagues were in on the test and I have read their individual on-field reports.
My recollection is that a good many of the WM's tested in this experiment were in "good, clean whitespace." Let's think it through - a WM hidden in an occupied analog TV channel should be protected by the much stronger carriers of that station. If the whitespace-using net gear is equipped to use such small interstitial spaces as WMs use, it should be sensitive enough to detect WM carriers therein.
I suspect Mr. Page's remarks are fed by a badly underling-filtered early version of the report (or leak).
Comment removed based on user account deletion
Only within the Continental U.S., Hawaii and some U.S. territories. Let Google go offshore somewhere and set up a test facility. I doubt Mexico would care very much (probably just grease a few palms.)
I'm not Mexican but work here. It would be equally easy to grease the correct hands in gringoland so don't think you are in the land of perfect innocence!
Mexico is categorized as third world, though... It's not a value judgement on the worth of Mexico, it's simply a categorization used during the cold war which still lives on.
It's up to engineers working on a production system to bring something out of beta, kthx.
That would be the "D" component of R&D.
First, he didn't call it a third world country. Second, it actually is a third world country. So the only reason Mexicans would be disgusted is if they were stupid and easily offended.
Mis-diagnosis killed my brother. Seriously.
He was having pain in his left calf whenever he did light/moderate excercise. I don't mean running, I mean walking around the mall. He would cramp up after about 5 minutes, then when his muscle relaxed, he could continue walking for quite a while.
He went to at least three doctors and all three told him different things. 1) he just needed more exercise. 2) it was a torn or damaged muscle 3) he needed more potassium. This is in spite of the fact that he had the symptoms for three years before his death.
Actual answer: Severe atherosclerosis which lead to myocardiac infarction (heart attack), and death.
It was surprisingly easy to figure out from the symptoms and a few websites. I was shocked that none of them thought to mention the possibility, and that they all discounted each others diagnoses.
White space is not defined as the small padding between documented frequencies, thogh a spall part of it exists there. White space are the UNUSED frequencies in many markets.
You see, there are more than 40 TV broadcast chanels available, and a further 81 digital channels as well, but in any one market or area, typically no more than 10 are ever in use. There is some small bleed over from one market to another, so maybe 15-18 of the channels may have some signal detectable and thus needing to be avoides.
Wireless microphones are poretty much the only other dev ice allowed to operate in this range. Where TV might cover 100 mile radius of effect, mics have at best a mile or so. There are a lot more of them in use, upwards of 40 for a single concert, and dozens at each TV studio, and your local bands and clubs each may use a few, but I know a few guys in bands, and they donlt seem to have any issues with signal crossover themselves when setting up their gear, so there are clearly not so many of these in use that it's a big issue.
a white space detecting wi-fi system would simply scan the spectrum and find a frequenct it detects no power on at all. Then, if it feels its safe, it powers on its anteanna and begins broadcasting, but that's not where it stops. Should it detect a signal after its picked one, its supposed to automatically fail over to a backup frequency (it also scanned for) and instantly stop broadcasting on the first until it determines the nature of that signal (perhaps it's just anotehr wi-fi base station that it can co-exist with).
Now, we're also not talking about using these things in home deployments. The purpose of this frequency is that it penetrates walls and has a significant range for a small amount of gain. Home users don;t need a wi-fi base station with a 5 mile radious of effect... This is for municipal deployment, large campuses, park areas, etc. Busineses won't use it because the range is so great, it's a security risk. In any geographic area, an ISP would deploy these things in a grid pattern, likely each 2-3 miles apart, so there's reasonable signal coverage even if one fails. This means at any one spot, an ISP might be using 5 signals, which I might add use a tighter digital signal range than TV, so 2 or 3 of these might take the channel space of 1 TV station. Maybe there's 3 or 4 ISPs in an area that size with simalar devices, so potentially we're talking 16-20 radios, which might use 20% of the white space in a given 5 mile radius, of which less than 20% more is in use by broadcast TV stations. This leaves 60% of the digital frequenct range for wireless microphones... 3 times what either TV or Wi-Max are getting. Why is this an issue?
Besides, for wireless mics, they can change frequencies! TV stations can't, but when your engineer powers on a mic, he checks for interferernce. If it's a bad, channel, he changes it. Once the mic is on, since Wi-max would not interfere, the only other potential for interference is someone else using a mic on the same channel. They're used to that. Even if WiMax was using the frequency when he turned it on, it would stop and the mic would get a clear signal unless another mic was also came on.
I think the only thing we might be able to propose is limiting wimax deployment into white space to a certain number of operating base stations on seperate chanels (some will be bridges on the same channel, so they don;t count). Say, limit to to 25 or 30% of the total available white space, and if it comes on and there's not enough, it should report an error. Again, this is limited to ISPs and big municipalities, so I really doubt we'd even hit this number of stations operating at once anyway.
There is no contest in life for which the unprepared have the advantage.
Of course there are. There are also lighting requirements to prevent aircraft from smashing into them in the dark. But my point was that Google wouldn't be attempting to do anything nefarious and thereby exploit Mexico's third world status, not that there's no danger whatsoever from a radio antenna.
Maxim: People cannot follow directions.
Increases in truth directly with the length of time spent explaining them
Tests rigged? That's not what I get from the director of advanced development for Shure Brothers Microphones, Edgar Reihl.
He was there for the tests last month.
See this article in Broadcast Engineering magazine:
http://broadcastengineering.com/hdtv/reihl-sheds-light-wsd-tests20080819/index.html