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Communications The Internet United States Wireless Networking Hardware

FCC Publishes "White Spaces" Rules 63

Stellian writes "The Federal Communications Commission adopted a Second Report and Order that establishes rules to allow new, sophisticated wireless devices to operate in broadcast television spectrum on a secondary basis at locations where that spectrum is open. It's the first time we have access to clear specifications for these devices, dubbed TVBDs — 'TV band devices' by the FCC. The published guidelines allow manufactures to create protocols and build compatible devices, which could be available in 18 Months, according to Larry Page. The full PDF text of this Second R&O is published on the FCC site."
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FCC Publishes "White Spaces" Rules

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  • by chaboud ( 231590 ) on Wednesday November 19, 2008 @03:10PM (#25822699) Homepage Journal

    So, TVBD's (whitespace devices) can operate on channels 21-51, except 37.
    So, wireless mics get 19 channels, minus TV presence. (37 is for radioastronomy)

    Unless it's two fixed-location devices talking to each other, then TVBD's can operate on 2, and 5-20. In markets with PLMRS, two channels will be reserved for wireless mics.
    Um 2-4? Minus TV?

    Except that TVBD's will be allowed to operate without geo-sensing, so they won't have any idea that they're in a PLMRS market.
    So, 2? Hello? Is this thing on?

    These TVBD's have been shown to interfere with TV at 40mW, and we're talking about devices that operate at 100mW? So the lesson here kids is that you should never bother buying an FCC license. You should just buy the people that make the rules. I can't wait for devices that allow for cheap (free would be better) internet everywhere, but this is not the FCC doing its job. Verizon and AT&T must feel like suckers for pouring money into Auction 73. Why buy the cow when you can get the milk for free?

    • Re: (Score:2, Insightful)

      Remember, TV channels are much larger (6mhz) than is needed for audio-only signals.
      • by chaboud ( 231590 ) on Wednesday November 19, 2008 @03:26PM (#25822923) Homepage Journal

        Sure. 2 TV channels is 12MHz, and mics need between 100 and 500KHz each, but there's always intermodulation [wikipedia.org] to ruin your day. Also, at a big event, with lots of broadcast coverage, you'll eat up 40 channels in no time. This is going to get really ugly really quickly.

        We will have at least one of the following in the next couple of years:

        - Interference that affects nearly everyone.
        - A somewhat-subjective standard that no devices pass FCC tests on.
        - An FCC reversal on this ruling.

        All of these are really bad.

        • So how's life at Shure these days? You guys hiring?

          • by chaboud ( 231590 )

            Dude. I work for Sony (and desperately want these devices to work). My wife works for Shure. You can imagine how our arguments about this technology have gone.

            Yes, they're hiring. So are we, actually.

        • Re: (Score:3, Insightful)

          by theaveng ( 1243528 )

          Good summary.

          Another facet to consider: TV Band Devices don't have to respect neighboring markets. For example I live in Lancaster PA which is protected, but I can also watch Philadelphia and Baltimore..... and a TVBD is free to broadcast directly overtop those non-local channels.

          So I might as well kiss Philly and Baltimore goodbye. No more channels 2, 3, 6, 10, 11, 12, 13, 17, 35, 45, 57, 61, or 65 due to TVBDs using those channels.

    • by Hatta ( 162192 )

      These TVBD's have been shown to interfere with TV at 40mW, and we're talking about devices that operate at 100mW?

      So what do we do? My digital TV reception is already marginal, I can't have it get any worse and still expect to be able to watch TV. If my TV starts dropping out a lot more than usual, how do I demonstrate that it's because of interference? Once I've demonstrated that, what recourse do I have? File a complaint with the FCC? Sue?

      • by maxume ( 22995 )

        Frequencies and outputs change at the transition. The first step is to wait until then.

      • The only solution I can think to do is monitor your neighbors. The TV Band devices would have to be within 1-2 football fields to overpower a full-strength TV channel, so if you experience interference it's probably coming from next-door or across the street. Once you locate the TV Band device, per FCC rule, they are required to turn it off. They are NOT allowed to continue operation while it is interfering with television (the primary owner of the channel).
    • Re: (Score:3, Insightful)

      by Detritus ( 11846 )
      These TVBD's have been shown to interfere with TV at 40mW, and we're talking about devices that operate at 100mW?

      Under what conditions? This is a good example of a test where you can guarantee success or failure by adjusting the test conditions. Who is paying for the testing and what is the desired result? I can think of multiple ways that the testing conditions can be manipulated to guarantee the desired result.

      • Re: (Score:3, Informative)

        by theaveng ( 1243528 )

        By the time a distant signal reaches your set, it's only ~10 milliwatts. A 40,000 milliwatt TV Band device can easily overpower that. It's more commonsense (40000>>>10) than any real need for testing.

        However if you insist upon tests, the ones performed by NAB and the Cable Association show any TV Band device within 1-2 football fields will overpower a broadcast television station. You'll end-up watching digital hash noise rather than the sports game or the latest episode of "Legend of the Seeker

        • Re: (Score:3, Informative)

          by theaveng ( 1243528 )

          Correction:

          "By the time a distant signal reaches your set, it's only ~10 [micro]watts. A 40,000 [micro]watt TV Band device can easily overpower that."

      • by chaboud ( 231590 )

        The FCC tests were public, and everyone who had any contact with the tests, including Larry Page [informationweek.com] agreed that the devices interfered.

        The only ones who called the test a success were the writers of the FCC report. Larry Page was crying foul about the tests being too hard ("rigged") right up until they issued their report because the devices interfered .

        These things are going to knock out rural TV and get approved anyway or not get approved. If they don't get approved, we all lose. The bands auctioned off

        • TV Band Devices have already been approved. It's only a matter of time until your neighbor has an Ipod or similar internet-capable gadget broadcasting on channels 2 to 51.

          • by chaboud ( 231590 )

            I meant specific devices, but, yes, it is only a matter of time. Me? I'll just watch Hulu, but I understand why this is a bad thing to do.

            • Unless Comcast decides you've passed their threshold as a "bandwidth hog" and they impose a temporary speed limit on you. From what I've heard the temporary speed limit is 128k which makes watching hulu.com impossible.

              • by chaboud ( 231590 )

                AT&T DSL, but the point is taken. We're being screwed on all fronts.

                • Pretty much. Soon you won't be able to access television for free. You'll have to join cable, join dish, or pay extra for non-speed-limited TV streams over the internet.

  • Erm. (Score:5, Insightful)

    by cosmocain ( 1060326 ) on Wednesday November 19, 2008 @03:21PM (#25822857)

    The database will be established and administered by a third party, or parties, to be selected through a public notice process to solicit interested parties.

    1. Such a database can't be operated at no (or low) cost.

    The locations where wireless microphones are used, such as entertainment venues and for sporting events, can be registered in the database and will be protected as for other services.

    2. Registering such devices will most propable cost money to keep up with the expenses needed for operating the database.
    3. To save money people won't register their devices.
    4. ???
    5. Pro...erm... Interference.

    • Good summary.

      Another facet to consider: TV Band Devices don't have to respect neighboring markets. For example I live in Lancaster PA which is protected, but I can also watch Philadelphia and Baltimore..... and a TVBD is free to broadcast directly overtop those non-local channels.

      So I might as well kiss Philly and Baltimore goodbye. No more channels 2,3,6,10,11,12,13,17,35,45,57,61, 65.

  • by HTH NE1 ( 675604 ) on Wednesday November 19, 2008 @03:23PM (#25822889)

    What is the FCC doing specifying how I indent my code? That's the job of the GCC, isn't it?

  • by nsayer ( 86181 ) * <nsayer@kfu.cELIOTom minus poet> on Wednesday November 19, 2008 @04:04PM (#25823481) Homepage

    I know something about this. I am one of the vanishingly small number of people who have set up an ATSC transmitter [youtube.com] other than under FCC part 70 rules.

    The sad reality is that 85% of people get their TV from cable or satellite, meaning that TVBDs will have zero impact on them (the cable and satellite companies either get their feeds over fiber or will have no trouble hunting down any source of interference that keeps the head-end from getting a signal, given their budget as compared to the average homeowner).

    One of the big time losers in the switch to digital broadcasting are mobile/portable receivers. I have an Insignia 7" LCD ATSC TV, and unless you plug it into a proper TV antenna mounted on top of a building, it's digital tuner is deaf as a post. Insignia stopped making them, probably because as portable devices, they're practically useless. And that's not Insignia's fault. It's simply the nature of the cliff effect. Portable receivers used to get by because they could display a less-than-perfect signal. But digital receivers get perfect reception or none at all. Mobile reception is out because the Doppler effect and dynamic multipath can totally wreck 8VSB reception.

    So what's left are people either too cheap or too poor for cable or satellite, or who (like me) are RF hobbyists.

    How low does that 15% figure have to go before it's simply cheaper for the government to subsidize lifeline access rates for the poor and auction the rest of the broadcast TV bands off? For how much longer is the public interest better served by broadcast TV rather than, oh I don't know, how about really, really high speed mobile IP (the sort of thing you can get when you set aside a 300 MHz band for the purpose)?

    TVBDs that cause interference will be impossible for the average broadcast TV viewer to diagnose. Their receiver will simply go blue-screen. In the past, there were visual clues in the picture condition to diagnose reception problems. But with the switch to digital, it would take a spectrum analyzer [youtube.com] to do the same job. The fact that the FCC would countenance such a situation speaks volumes about how important they perceive broadcast television to be.

    • by Areyoukiddingme ( 1289470 ) on Wednesday November 19, 2008 @04:13PM (#25823617)

      The fact that the FCC would countenance such a situation speaks volumes about how important they perceive broadcast television to be.

      Which is exactly how it should be. It was something like a decade ago that somebody made the sage observation that America had its data transmission systems completely upside down (for historical reasons only). The huge high bandwidth signals were over the air (broadcast TV) and the tiny low bandwidth signals (phones) were over cables. The populace has been working hard to reverse one part of that state of affairs, buying cellular phones. Shoving the television signal into a wire where it belongs is the next step.

      Yes, the next thing that will happen is a Federal Universal Access Fee on cable. Because some dumbass will think it's "fair" that the cable company pass those costs on to the consumer for recovery in 30 seconds of billing, instead of acting like a utility and recovering their costs over decades. But that's another rant...

      • by nsayer ( 86181 ) *

        Which is exactly how it should be.

        I don't disagree.

        The populace has been working hard to reverse one part of that state of affairs, buying cellular phones.

        Well, they've been working hard to reverse the other one as well, by signing up for cable and satellite TV.

        a wire where it belongs

        Well, an alternative to a wire is to move it upwards in frequency to SHF... like satellites have done. Higher frequencies have a much higher penalty for mobile use relative to their utility in point-to-multipoint line-of-sight linking (which is precisely what TV broadcasting involves).

      • Re: (Score:3, Interesting)

        by theaveng ( 1243528 )

        Let's see. Approximately 18% or 20 million homes watch television over the air, exclusively. Some by choice, some because they are farmers living in Montana or some other rural state lacking wires, and some because they can't afford a $60 a month cable bill.

        If the government discontinued broadcast television and instead subsidized Dish locals-only service to everybody, that would cost $11 a month per home. The total expenditure would be $2.7 billion per year. Are you sure we really want to

        • by nsayer ( 86181 ) *

          Are you sure we really want to spend that much money?

          Given that the spectrum license fees for that much spectrum might be as much as 10 times that, um, yeah.

          Over-the-air television doesn't cost the government anything

          In fact, it makes money for the government because they charge the stations fees for their licenses. But the question is whether the public is best served by that spectrum being used as it is, or perhaps in some other way.

          Today, it's probably good the way it is, but for how much longer?

          But the cost of that convenience is around $50 a month

          Today. I've had a cell phone since the mid 90s, and the cost:benefit ratio has maybe not been following Moore's law, but

    • by Detritus ( 11846 )
      Advances are being made in ATSC receiver technology that improve performance in multipath environments. I wouldn't write off the technology for mobile and portable use. We haven't reached the point where ATSC receiver performance can no longer be improved. Where I live, a cheap ATSC converter box actually outperforms analog TV for weak signals.
      • Re: (Score:3, Informative)

        by nsayer ( 86181 ) *

        Advances are being made in ATSC receiver technology that improve performance in multipath environments

        I agree, for static multipath, but dynamic multipath is going to be nearly impossible to fix for 8VSB. ATSC is, in fact, working on an add-on to support mobile device reception to make up for the inability for 8VSB to stand up to dynamic multipath and doppler.

    • by dbc ( 135354 )

      So what's left are people either too cheap or too poor for cable or satellite, or who (like me) are RF hobbyists.

      You left out rural Americans. Those who currently live far from any metropolitan area are going to see their channel choices severely reduced. I suspect my inlaws will have zero choices in television viewing after the switch -- whereas now they get fringe reception from 10 or so stations in various directions, using a decent outdoor antenna.

      There is no way any cable company is going to be wiring the area where they live -- there is about one television-owning family per square mile. (I say television-owni

      • by nsayer ( 86181 ) *

        You left out rural Americans.

        No, I didn't.

        Those who currently live far from any metropolitan area

        ... are satellite TV subscribers instead of being cable subscribers.

  • This has screwed many in the live event industry because many of our wireless mics are now unable to be used. Everything from concerts, to hotels, production companies, theme parks, bars, clubs, are going to suffer.

    Here is some discussion by my fellow audio engineers on the subject:
    http://srforums.prosoundweb.com/index.php/t/39317/2112/ [prosoundweb.com]
    http://srforums.prosoundweb.com/index.php/t/39317/2112/ [prosoundweb.com]
    http://srforums.prosoundweb.com/index.php/t/39629/2112/ [prosoundweb.com]

On a clear disk you can seek forever. -- P. Denning

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