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Why We Need Unlicensed White-Space Broadband Spectrum
pgoldtho writes "PC Mag has a story about why the 'white-space' spectrum that will be freed when TV broadcasts switch to digital should be available for unlicensed use. This would allow it to be used to deliver broadband connectivity in rural areas and create a 'third pipe' alternative to the cable/telco duopoly. The FCC is scheduled to vote on this November 4th. The National Association of Broadcasters (NAB) has filed an emergency appeal to block this vote. If the NAB succeeds, the issue will be kicked into next year. Which would mean a new FCC, Congress, and Administration."
Too late. In Qualitex Co. v. Jacobson Products Co., SCOTUS held that, "sometimes, a color will meet ordinary legal trademark requirements. And, when it does so, no special legal rule prevents color alone from serving as a trademark." They awarded trademark rights to "green-gold" to Qualitex.
But of course, the issues are very different. Even at the physical level - most matter is opaque to the visible spectrum but transparent to radio.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
Unlicensed doesn't just mean a free for all. It would be regulated in much the same way the many existing radio services are. The new users would have to make sure they operate in such a way that the primary user is not affected in any negative way. This includes ceasing transmissions completely if necessary to avoid interference. If you violate it and a primary user complains, eventually you're going to attract attention from the FCC, and they will fine you.
Running at less than half the frequency of WiFi, it will do considerably better at going through obstacles, but it's not LF, it's not going to travel hundreds of miles and skip of the ionosphere... You're ALWAYS going to be constrained by line of sight and the curvature of the earth.
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"Unlicensed" doesn't mean "unregulated". Licensed spectrum means that only one organization is in control of the spectrum, but even that doesn't prevent someone from setting up a jammer. I believe the FCC controls what radios can be sold on the market (i.e. the equipment must use this new-fangled "cognitive radio" scheme, and must hook into the FCC database of known incumbent signals), and as well, the FCC can try to locate someone who is persistently jamming.
Wouldn't there be huge amounts of interference if the spectrum was unlicensed? Could someone not just make a jammer for the frequencies in question and spoil it for everyone? Or do FCC laws cover that even when it's not formally licensed? IANAEE.
FCC Regulations, Part 15 covers this in great detail.
Here's an excerpt from sub-section 5
If a Part 15 transmitter does cause interference to authorized radio communications, even if the transmitter complies with all of the technical standards and equipment authorization requirements in the FCC rules, then its operator will be required to cease operation, at least until the interference problem is corrected.
Here is a PDF from the FCC entitled "UNDERSTANDING THE FCC REGULATIONS FOR LOW-POWER, NON-LICENSED TRANSMITTERS", which is exactly the rules which would be applicable to the hardware used for accessing the White-Space Broadband Spectrum .
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"I can't complain, but sometimes still do..." Joe Walsh
This is actually informative if you remove every instance of the word "fuck"!
It'd be like all the things we already do on unlicensed spectrum. Think 802.11b/g WiFi and 2.4 cordless phones running on overlapping frequncies. So possibly a lot of noise in heavy use areas. However, regulations specifying manufactured capabilities and use of items will still be made by the FCC, so intentional jammers will still be a no-no.
While I love the idea of free and open internet communication (unlikely if we farm this out to Google and Microsoft), if they plan on using the performances they've seen in FCC tests as the benchmark, you can expect even your cable TV to cut out. I absolutely love the concept, but the simple fact is that current versions of these devices don't work, and Kevin Martin is for sale.
I'd put $50 on him ending up at Google or Microsoft within a year of leaving the FCC. Anyone who talks with the people who were at the white-space device tests knows that these devices failed miserably. If you think the iPhone (or any GSM phone, honestly) next to your speakers is annoying, just wait for these puppies.
Stories like this one make my head spin. For some reason, people simply can't seem to get the engineering issues through their heads.
Prototype devices tested by the FCC earlier this summer were shown to be capable of detecting Digital TV stations. However, they were not even close to capable of detecting wireless audio devices such as microphones, in-ear monitors, wireless intercom systems, and IFB devices. You may not realize it, but these devices are all around you, and chances are, they are mission-critical devices for television stations (think about reporters in the field), theatres (from your local high school to The Phantom on Broadway), professional sports (almost all professional sports games use copious amounts of wireless intercom and microphones), houses of worship (if you go to church, chances are you are in the vicinity of wireless microphones), concerts (almost all concerts rely on wireless microphones and in-ear monitors these days), and many other people.
All it takes is one single white space device to fire up on top of one of these wireless audio devices to knock it off the air, and there is no good solution - we cannot go digital, because of power and fidelity concerns; we cannot go to another band, because there are no real options (and because of the cost - it would cost my theater $50,000 to refit our space); and we cannot simply go "off the air."
Let us be clear as well about who will be using these white space devices. They will NOT be used to provide rural broadband (as one person noted above, this need is already covered by 900 MHz devices), at least in the beginning. The first devices to market will be gadgets like the iPhone that everyone will see as a "must have." It will work like Wi-Fi, but will cause far more interference because it will be everywhere - in church, in the theatre, and at the game.
All of this is not to say that it is impossible for white space devices to work together with wireless audio devices. All that is required is for white space devices to not transmit on top of a wireless audio device. In the future, wireless audio devices may be able to avoid other devices by themselves, but for now white space devices must bear the burden of not causing harmful interference to other users of the space (some of which are currently not licensed, and some of which are actually LICENSED for operating in the TV band!) But this is an engineering challenge, and not a political one. Let us hope that the FCC realizes this, and listens to its own engineers - and not politicians, lobbyists, and naysayers.
No, not correct at all.
Whether it will work or not depends on how many degrees of curvature the signal has to disperse across to go "around" the hill in question.
The higher the frequency, the less the signal will "curve" around such obstacles. With UHF being less than half the frequency of WiFi, you can expect it will do a much better job of going around hills, and any other conceivable obstacle. That should allow you to get connectivity in more spots than you otherwise would, but it's never going to work in all situations.
If you have two transceivers at opposite sides of the base of a mountain, no radio frequency is ever going to allow them to communicate directly (well, VLF will, but that's impractically slow, so let's ignore it for simplicity sake). If they have line of sight, just about any frequency will work. As the obstacle between them, blocking line-of-sight communication gets larger, lower frequencies are required to circumvent it.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Perhaps, they just read your post and realized it was mostly unsubstantiated bullshiting in the fine fashion of Microsoft/Neocon/Fox News FUD.
Perhaps, they aren't modding you down because they disagree with you but because you didn't add squat to the discussion.
A 100 milliwatt WSD will travel about four football fields distance. If the WSD is broadcasting on VHF (channels 2-13), it won't be blocked by trees, but if it's broadcasting on UHF (channels 14-51), then trees will block the signal quite easily.
FOX NEWS.com should be BANNED from television and internet. Have the Congress take it over and give us Truespeak.
1) Spectrum being freed up.
No. No spectrum is freed up by switching from analog to digital. A digital station takes up 6Mhz, same as an analog station. It's true that the FCC has relaxed adjacent channel restrictions, but any spectrum freed by that is balanced by the loss of channels 52-69, which have already been auctioned off. There's no truly free high-VHF or UHF slot between New York and Baltimore; spectrum's full.
2) WSDs being able to detect stations
For a WSD to reliably detect another transmitter, it would have to be as sensitive and have as good an antenna as the intended reciever. What are the chances of that, particularly in a portable device? Sure, your little iAndroZune with its 2" stub can't detect the channel, but my purpose-built TV tuner with a 10dBi antenna could pick it up fine... or it could, until the iAndroZune started stepping all over it.
3) Won't interfere even assuming it finds a white space
The front-end filters on TV tuners have about a 5-channel passband. A strong signal anywhere in there can cause the RF amp to overload or force the AGC to cut in and thus desensitize the tuner. One of the FCCs own studies showed it could be cause up to 70dB of sensitivity loss on adjecent channels, which makes the difference between very good reception and none at all. Furthermore, those of us using a pre-amp to receive weaker stations don't have the benefit of front-end filtering; a white space device anywhere in the band can cause problems throughout the band. Note that some of those little USB stick tuners don't have front-end filtering either.
Except for one pertinent instance of "fuck", all others removed and the grammar slightly altered to make up for it. Otherwise this is the exact same post as above.
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The government, isn't trying to own the white space networks. Google and a few other companies are trying to do something good for society. People like you are trying to ruin everything because you can't understand common sense. They will probably make some money for their efforts, but for fucks sake, they deserve to make some cash for all that work. You, on the other hand, probably think that you alone are worthy of getting something for free while everybody else needs to pay. Perhaps next time you can read something about the issue before shooting off your mouth about shit you have no clue about?
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It's good to hear that the FCC is so attuned to the problems of RFI and TVI. Otherwise I'd be really worried about the practice in the Deep South where right-wing broadcasters manage to license frequencies adjacent to NPR stations, and effectively drown them off the air. Since the FCC is so concerned, of course they're going to address this.
The living have better things to do than to continue hating the dead.