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Communications Wireless Networking The Internet Hardware Technology

Google Looks to "White Space" Spectrum 95

Posted by Zonk from the making-the-most-of-what-you-have dept.
Nerdposeur writes "After maneuvering the major carriers into agreeing to open access rules via the recent spectrum auction, Google appears to be looking into a new area of spectrum that could provide internet connectivity. 'In comments filed with the Federal Communications Commission, the Internet leader outlined plans for low-power devices that use local wireless airwaves to access the 'white space' between television channels. A Google executive called the plan 'Wi-Fi 2.0 or Wi-Fi on steroids.' Interestingly, Google has Microsoft, Intel, and others on their side in this one. Was this spectrum their target all along?"
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Google Looks to "White Space" Spectrum More

Google Looks to "White Space" Spectrum

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  • Microsoft Device (Score:5, Informative)

    by Pointy McButterpants ( 1183327 ) on Tuesday March 25, 2008 @11:11AM (#22858600) Homepage
    Is this the same technology that Microsoft has tried to demo (twice) with less-than-spectacular results?

    • Re: (Score:1, Offtopic)

      by Brian Gordon ( 987471 )
      Are these the same steroids that hackers are on? Couldn't that be a security risk?
      • Woah.

        Woah.

        Woah. Stop. Is this so-called "between television channels" technology going to stop me from watching channel 5 in D.C.? (80 miles distant). I don't like the idea of some corporation or person deciding, "Well channel 5 is not used in southeast Pennsylvania, so I'll broadcast there," and wipe out my weak but still watchable television 5.

        • Re:Microsoft Device (Score:5, Informative)

          by Megane ( 129182 ) on Tuesday March 25, 2008 @01:42PM (#22860918)

          Woah.

          Woah.

          Your "weak but still watchable televsion 5" will disappear in 11 months anyhow, [wikipedia.org] before any of this can get implemented. And since channels 2-5 are generally bad for DTV, they will probably keep their new channel, which is almost certainly UHF.

          And depending on lots of factors, including antenna direction and getting a relatively recent DTV tuner, your "weak but still watchable" signal might get replaced with a crystal-clear signal. (DTV actually has more problems within 10-20 miles of the transmitter than with distant reception.)

          • Re: (Score:3, Insightful)

            by soupdevil ( 587476 )
            Digital degrades poorly. I'm about 20 miles from most of the nearest transmitters. The analog signals are fuzzy, but quite watchable. The digital signals are completely useless, frequently going to blue screen. I have tried multiple indoor and outdoor antennas with the same result. When analog signals go away, I'll be watching torrents, I guess.
            • No, analog degradation is gradual but always present and increases with distance. Digital degradation does not even exist until a certain threshold of signal quality is passed, and then drops off steeply.

              • Re: (Score:1)

                by blippo ( 158203 )
                Not quite true...

                It seems that wind (trees and leafs) or rain intermittently pushes the signal quality down the slope, rather annoyingly.

                Something that might have caused a small flicker on an analog tv is replaced by a minute long mpeg blur.

                • Yes. Digital dropouts are far more annoying than the ghosting on analog. If the FCC were serving the People, instead of the Corporations, they would have done tests to see what the People prefer. I suspect most would say they'd rather have ghosting analog.

                  In any case, rabbit ears have proved worthless.

                  I acquired a Channel Master 4228 antenna which is extremely directional. It can pull in UHF 70 miles distant and VHF 100 miles distant, although it must be aimed very precisely (within one degree).

            • Re:Microsoft Device (Score:4, Informative)

              by Megane ( 129182 ) on Tuesday March 25, 2008 @06:16PM (#22864154)

              If you're having trouble at 20 miles, then your problem is multipath interference. Basically, reflections of the signal off of various objects in an urban area are delayed copies of the original signal. With an analog tuner, this results in ghosting. With a digital tuner, this results in being unable to decode the digital signal. Older ATSC tuners in particular are very bad about rejecting multipath interference.

              Rotating your antenna will affect your signal quality. (I have to adjust my roof antenna every two or three months because winds knock it out of position and I lose CBS.) Installing an attenuator in the signal path may result in better reception. The worst thing you can do when you are that close to the transmitter is to use an amplified antenna. The amplifier may distort the signal in a way that reduces the signal quality.

              Also, your tuner should have a signal "strength" display. This is usually in fact a signal quality display. Often 75% is the threshold below which there is not enough good data for the error correction to work. If it has an audible signal meter, turn up the TV volume to where you can hear it outside while adjusting the antenna, and set it to the most finicky channel.

          • >>"Your weak but still watchable televsion 5 will disappear in 11 months anyhow,"

            No it won't.

            It will still be there as digital channel 5. Along with digital channel 6, 8, 10, 11, 12, and so on.

            My concern was whether or not some guy with a Google White Space thingie decides to broadcast on those channels, because he (mistakenly) believes they are empty. That would not make me happy.

            • Re: (Score:2)

              by Megane ( 129182 )

              ATSC allows the station to "lie" about what channel you are watching. It might still be named channel 5 in the PSIP (the station ID information), but that doesn't mean that it is broadcasting on the channel 5 frequency. Most 2-6 stations will be keeping their UHF channel. What gets done about the PSIP channel numbers after the cutoff remains to be seen, but tuners could get confused if the old channel gets reused by a new station, while the old channel number is still in the first station's PSIP. (are YOU c

        • Re: (Score:1)

          by Isaac-Lew ( 623 )
          After February 17, 2009 (if not sooner), you won't be able to get the analog signal for Channel 5 anyway. Does the digital signal go out that far?

      • Re: (Score:1)

        by Blice ( 1208832 )
        Hackers on steroids are a security risk. Luckily, if you buy curtains for your windows and a dog, you should be okay.
    • Microsft with less-than-spectacular results? Say it isn't so.

      Look, no doubt MS screwed it up. But I suspect that Google will be working a few hardware companies who know what they are doing. Issue solved. Of course, getting the fcc to agree is still the real issue, and I am guessing that it will be fought by everybody else.
    • Google being Devious? Or Microsoft maneuvering Google into doing what it wants?

    • Is this the same technology that Microsoft has tried to demo (twice) with less-than-spectacular results?

      By "less-than-spectacular results" do you mean that they merely failed, just not in a Vista sort of way?

      And remember that Microsoft's trying something twice and failing provides no evidence against its feasibility. Using the white space requires absolutely playing nice with others, only using what's genuinely available, and being sensitive to others' use of spectrum. This means being respectful of use

  • when I was kid (Score:5, Funny)

    by JeanBaptiste ( 537955 ) on Tuesday March 25, 2008 @11:16AM (#22858700)
    you could tune the satellite to be almost on a station, right on the 'edge' of the station, and get around the blocking method they used for PPV... you would get a blurry picture but good sound. Great way to watch porn when you're a 12 year old.

    Don't take that away google. Think of the children.

    • Re: (Score:3, Funny)

      by glavenoid ( 636808 )
      Heh, heh, I remember that.

      Johnny: What's that -- I think it's a boob!!
      Timmy: Nope, just some dude's shoulder. Maybe next time, Johnny.

    • Re: (Score:2)

      by Zach978 ( 98911 )
      Good ole' squigglevision...
    • Kid 1: "Hey, how is channel 99 at your house?"
      Kid 2: "Who cares about channel 99? I can get Natalie Portman with Hot Grits on channel 98.5!"

  • Already been done? (Score:1, Funny)

    by Anonymous Coward
    I seem to remember this a while back on the PBS stations in my area. They would push this content across the space between the channels. The only issue at that time, I thought, was that you were only allowed to receive what they gave you and not have a two way street... I don't think this is a particularly new idea. Oh yeah - I didn't read the article... so if I am off the mark, oh well.

    • Re: (Score:3, Informative)

      by qbzzt ( 11136 )
      You're talking about teletext [wikipedia.org]. It used extra space in the TV channel for text broadcast. With today's technology, the same bandwidth can be used for decent bandwidth communication instead. The two are not really related except for using the same frequencies.

      • Re: (Score:1, Interesting)

        by Anonymous Coward
        Nope, actually this: http://findarticles.com/p/articles/mi_m0DIZ/is_11_13/ai_72270397 [findarticles.com] Which may be seen as an early extremely limited trial of this (depending on how you look at it).

      • Re:Already been done? (Score:4, Informative)

        by TheRaven64 ( 641858 ) on Tuesday March 25, 2008 @12:44PM (#22860136) Journal
        Teletext doesn't use space between channels, it uses space between frames. Analogue TV is a modulated version of the signal that is sent directly into the CRT. For each line, there is a series of peaks and troughs setting the intensity along the scan line[1]. TV resolutions are defined in terms of a number of lines and an aspect ration, rather than a number of columns, for exactly this reason, since signal along a line is analogue (you can squeeze in more, smaller, pixels if you have a good enough signal to noise ratio). At the end of each line, the electron gun is turned off and moved to the start of the next one (you could scan alternate lines right-to-left, but I don't think anyone does. I could be wrong though). At the end of each frame (technically, each field, since TV is interlaced), the gun is turned off again and repositioned pointing at the top-left of the next field.

        Each of these repositioning takes time and the signal transmitted in this period is ignored by the TV (since the gun is turned off). Teletext works by encoding digital data in the signal during this period. You can only transmit a small amount of data in this period, but you can do it every frame and it will be buffered inside the receiver.

        [1] Colour TV is slightly more complicated.

  • Comment removed (Score:5, Funny)

    by account_deleted ( 4530225 ) on Tuesday March 25, 2008 @11:24AM (#22858824)
    Comment removed based on user account deletion

  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Tuesday March 25, 2008 @11:27AM (#22858876)
    Comment removed based on user account deletion

    • Re: (Score:2, Insightful)

      by Hadlock ( 143607 )
      I was under the impression that the recent auction was for this exact spectrum that was being freed up. If this spectrum isn't forecast to be used with anything new, why are we turning off analog transmission again?

      • Re: (Score:1)

        by daenris ( 892027 )
        I'm not positive, but I believe the spectrum auctioned was for the frequencies of the actual TV channels. Google is now after the small gaps in frequency between these ranges that were already auctioned.

        • Re: (Score:3, Insightful)

          by Hadlock ( 143607 )
          Ah-ha. Surely there is a graphical representation to explain this. Google image search to the rescue!

          So are the digital channels being moved from the gaps between the current analog stations to other frequencies? Or are these "micro frequencies" inbetween everything, and if so, why weren't they included in the original auction? The way the article paints it, it sounds like there's Very Large Swaths to be siezed still, and that google is So Clever for noticing these before everyone else. I feel like

    • Re: (Score:3)

      by sorak ( 246725 )

      Get your biggest competitor for bandwidth to spend all of their money on the spectrum you don't want by executing a feint in that direction, and then taking over the spectrum you really wanted.

      It's almost like someone who reads those business books that are based on military strategy actually figured out how to apply the military concepts to competition...

      Or maybe they read one of those "you can do it! Just visualize!" books and then visualized a kick-ass business tactic...

    • Re: (Score:2)

      by ajs ( 35943 )

      Get your biggest competitor for bandwidth to spend all of their money on the spectrum you don't want by executing a feint in that direction, and then taking over the spectrum you really wanted.
      No, I think this is a fallback. Google would have preferred to have outright purchased spectrum for cheap with open access requirements, but since that didn't work out, this is a close second (and it's an old idea, which the FCC has has yet been unwilling to move on).

    • (i'm one of those who read Sun Tzu, but i read it around 1989 or 1990, not in the late 90's with all the Johnny-come-latelies...)

      But, this White Space spectrum thing reminds me of when advertisers tried to take the "microsoft" desktop in the fringe areas of the screen display. Then, microsoft went ape-shit and made the usual threats, rants, and eternal damnation speeches and got the competitors to relent.

      On my old Gateway 2000 CrystalScan display here at work there is STILL a black border around the windoze

      • Those kinds of books have lots to say about life in general.


        More of this kind of thing can be found in the writings of Macheavelli, Clauswitz and Herman Kahn.


        'Macheavellian' is a compliment, and cool clear thinking even about the horrible is the best way to mitigate it.

      • Re: (Score:2)

        by Hadlock ( 143607 )
        On my old Gateway 2000 CrystalScan display
         
        I have one of those! Great, compact monitors with good color that lasts forever.
        • Well, it screws up my Feng Shui, this big honkin' monster thing.

          But, i'd rather have a 19" or 20+" flatscreen to get that cyclotron or magnet off my desk. 20" behind and 20" to the left of my partition sits the president, and if i fire up the monitor, it disrupts his LCD. He jokes, "Oh, my pace maker", sometimes. At least i keep it on energy save to shut off after 30 minutes of inactivity.
    • It sounds very likely. Higher frequencies allow for MIMO communications, which is the next step in comm. standards. You can't pull off MIMO in the 700 MHz spectrum, so perhaps Google is on the ball for this one.

      • Re: (Score:2)

        by Agripa ( 139780 )

        You can't pull off MIMO in the 700 MHz spectrum

        I am not particularly fond of MIMO but what precludes its use at 700 MHz? The 1/4 wave distance is about 4.2 inches so it would be inconvenient for most mobile devices but not for fixed installations.
        • If the mobile isn't running multiple antennas but the basestation is, you don't have MIMO, you have SIMO/MISO depending on your POV. What's your point?

          • Re: (Score:2)

            by Agripa ( 139780 )
            I took "Higher frequencies allow for MIMO communications . . . You can't pull off MIMO in the 700 MHz spectrum . . ." in your original post to mean that there was some technical reason MIMO would not work in the 700 MHz band. I was thinking that something changes enough in the multipath characteristics to preclude MIMO.

            My own experiences with multipath and fading (I used to do a lot of VHF and UHF transmitter hunting with my own equipment) lead me to believe operation down to almost 6 meters would be possi
            • MIMO works independently of frequency, provided you have uncorrelated antennas. At 700 MHz, the antenna spacing on a mobile (in terms of electrical length) is so close you can't design low correlation antennas. So provided your set of antennas can scale, MIMO works at any frequency. Unless people are willing to use much larger phones, 700 MHz (or 900 MHz) will not provide MIMO communications.

              That being said, designing MIMO antennas on a mobile (or any similarly sized object) at 2.4 - 2.5 GHz is quite eas

  • Just like MuniWiFi did. Google, where are your commitments to that??

    Just like WiMAX works so well .

    Just like Earthlink, master of all that's good, wireless, and now nearly bankrupt might think.

    Sure, software-defined radios might be nice. But let's put in real freaking fibre instead of still another plan to screw telcos/cellular carriers. If Google needs more bandwidth for YouTube, let them finally invest in the infrastructure to deliver it, not 'convenient' short-term wireless ploys. Egads.

    • Re: (Score:3, Interesting)

      by abertoll ( 460221 )
      Wireless Internet is desperately necessary. WiMAX and 3G are well on their way. And once you have reliable wireless Internet access, suddenly your costs are going to go down. It's just like what happened with cable and satellite TV. Before satellite, cable companies used to make you wait home all day for their technician to decide to show up or not. Now they've got it down to about an hour.

      And anyway it makes sense: the Internet is a shared resource, and there are a lot more opportunities for competi
      • We disagree. There is no wireless transmission media that can support the bidirectional broadband speeds necessary to fulfill burgeoning bandwidth needs. Such speeds aren't even on the horizon for wireless. In a single fibre, I can get transmission speeds far beyond what the backhaul is possibly able to deliver. If you invested in fiber 25 years ago, you can still use it today. The same cannot be said for wireless.

        Worse, there are no usable models for MAN distribution of wireless that make economic sense

  • It's a simple enough idea (Score:5, Informative)

    by zappepcs ( 820751 ) on Tuesday March 25, 2008 @11:35AM (#22859008) Journal
    and with digital television on the way, much easier to implement without interference. The UHF channels used on your television (most households in the USA have some cable or Satellite feed so don't use broadcast television really) have a small amount of bandwidth between each. If you combined that bandwidth with multiple radio links or some transmission technique, you could use it for WiFi like services locally in the home. The strength of signal could be such that it wouldn't interfere with neighbors reception ( as most aren't using broadcast television anyway) and it gives out more spectrum for home use.

    Additionally, there are methods to use a small footprint in the WiFi band to herd the small signals between tv channels. It would look like frequency hopping, require much smaller signal strength, and would cause negligible interference to broadcast television. Simpler still is to allow the user to input the television channels they do watch so that interference is even more remote. If you can steal (locally only) use of channels that are not used at all in the area (how many stations are on channel 63 or 42?), there is literally TONS of bandwidth to use, and all of it at a better frequency range for non-line-of-sight transmissions. That is to say; better signal quality at lower signal strengths.

    • Re: (Score:2, Funny)

      by Anonymous Coward
      Uh, that word, "literally", I don't think it means what you think it means. (Unless you are planning on adding up the weights of all the electrons used in the transmission perhaps?)

      • Re: (Score:2)

        by mgblst ( 80109 )
        I have notived this a lot recently. People seem to be adding the word in to make them sound more intelligent, which it probably does, to other people who don't understand the word.

        "I literally laughed my head off."

      • Re: (Score:2)

        by jc42 ( 318812 )
        literally [lit'-ra-li] adv. See figuratively.

    • Somebody mod this parent up. Very concise description. Good for those who don't really know what this is all about...
    • I can't help but argue with you. Spread spectrum communications aren't new. They require a lot of different frequencies, with low power. They often operate under the noise floor, which is why the military likes them so much.

      The problem is that the FCC likes to put restrictions in place on frequency, and on power. Since the UHF bandwidth now has a new owner, it's up to the new owner to decide what gets broadcasted there. Saying things like the google device will voluntarily avoid channels that are alrea

    • Re: (Score:2)

      by Agripa ( 139780 )

      The UHF channels used on your television (most households in the USA have some cable or Satellite feed so don't use broadcast television really) have a small amount of bandwidth between each. If you combined that bandwidth with multiple radio links or some transmission technique, you could use it for WiFi like services locally in the home. The strength of signal could be such that it wouldn't interfere with neighbors reception ( as most aren't using broadcast television anyway) and it gives out more spectru

  • http://code.google.com/p/spacesharp/

    I used to have a native x86 whitespace compiler, but I never could read my code.
  • This fragments the spectrum leaving you with a lot of fragments of two exact sizes perfectly interspersed. Down the road there you would have to take spectrum from both the "channel" and "space" allocations to make any block bigger then a single channel and dropping either spectrum would only give you back a sequence of broken spectrum. If some of this spectrum really should be re-allocated to something else surely it would make a lot more sense to take one or more channels from either or both ends? Wh
  • Those frequencies are called GUARD BANDS , they are seperation to prevent signal bleed-over.
    Perhaps Google has no real engineers working for them after all.

    • Re:White Noise? (Score:4, Informative)

      by RenderSeven ( 938535 ) on Tuesday March 25, 2008 @12:42PM (#22860098)
      Well, yessss, but guard bands (in lower case) are necessary for TV stations and such not to bleed into each other. That doesnt mean an entirely different modulation scheme wouldnt be able to utilize the bandwidth without interfering with the broadcasts. The newer software radios can operate below the noise threshold, and I can't see how more traditional broadcast methods would be interfered with. Older analog broadcasts are hugely wasteful of the RF spectrum.

      Perhaps Google engineers are just smarter than you are :-)

  • This just might be a great idea (Score:3, Interesting)

    by Whuffo ( 1043790 ) on Tuesday March 25, 2008 @12:15PM (#22859700) Homepage Journal
    I suspect that it won't be long before "internet" will be a basic service like "electricity" or "telephone".

    The only big problem left to solve before true high speed access would be available to nearly everyone is the method of distribution. Using existing service wiring is problematic. Telephone wires aren't adequate due to bandwidth and signal / noise problems. Running networking over power wiring is not workable; it has all the problems of using the phone wiring but much, much worse. Running networking over the cable TV systems is the most functional - but cable doesn't go to every town and house and not all cable systems are compatible.

    There's been a push to "wire" the country with glass fiber. They've even got it all the way to the house in some areas. As they build out the fiber networks they'll gradually reach more and more customers. But there's a BIG problem here: there's a huge number of houses and apartments to cover. The phone and electric systems grew up with the country, as each new home / subdivision was created these services were connected; essentially, the phone company took 100 years to get wiring to every residence.

    To start out now and try to connect every residence - the magnitude of this problem is staggering. Assuming 100 million residences, if the army of installers could run fiber to and connect 10,000 residences every day - it'd take over 27 years. And that assumes the installers would be working 7 days per week. I'm not even going to try to estimate the cost of doing this.

    If workable and reliable long-range wireless networking is developed / proven - and there's RF bandwidth that it can use - this could connect large number of residences inexpensively and quickly. Just plug your network cable into the "network radio" and you'd be online; no army of installers required. This would make it possible to make high speed access available to almost everyone in much, much less than 27 years.

    I'm glad to see that Google is putting their resources behind making this a reality. It's not going to be easy to make this kind of technology work reliably but there's some very bright people at Google and if anyone can find a solution they can.

    • The only real question left in my mind is how I will be paying off my debts when my wireless ISP is made irrelevant by Google. As a paranoid, I am certain that their goal all along has been to make internet available in the old broadcast tv spectrum, and then they can own rural United States access.

      Wanna buy an ISP?

    • Re: (Score:1)

      by DanJ_UK ( 980165 ) *
      Being a Google solution it should be a cheap one too :)
  • OK, here's an issue that I never see discussed when White Space devices come up. If I live in a fringe TV reception area and need an aerial 10m above the ground to get an adequate signal, a White Space transmitter at ground level next door isn't going to be able to see the TV signal. But when it assumes the spectrum is free and starts transmitting, boy is it going to knock out my TV reception!

    • Re: (Score:2)

      by Megane ( 129182 )

      It is a lot easier (especially with the new digital ATSC) to detect the presence of a carrier than to get a usable signal from the carrier. The white space devices will be able to detect a carrier at least as faint as -114dBm, which is very fringe indeed. It is also likely that your deep fringe antenna will be sufficiently directional so as to avoid the low-power signal, and that ATSC reception would not be affected by interference from a non-ATSC signal.

      I would also expect that there would be a way to con

  • There is an interesting online video lecture at Videolectures.net that is also talking about Whitespace Devices and discussing the battle between FCC and Broadcasters against the Whitespace Device movement. It is interesting that Microsoft appears to be a good-guy in this area.
    It is the big $$ broadcasting companies and the regulators that are opposing the WSD because they fear any competition.

    Check out the lecture at http://videolectures.net/kiblix07_meinrath_wtrr/ [videolectures.net] (the WSD part starts at around 42:00)

  • Dangerous for PAs (Score:3, Interesting)

    by aitikin ( 909209 ) on Tuesday March 25, 2008 @02:34PM (#22861608)
    This idea is horribly dangerous for anyone running a PA. That "whitespace" is where wireless mics run. They use UHF/VHF frequencies to communicate between the receiver and the mic itself. I recently toured the Shure Plant in Niles IL and they pointed out that these whitespace devices are causing an extremely large amount of harm to something that's already standardized to run in the whitespace. I don't know, it really kind of worries me that my wireless mic systems won't work anymore, or that, when I go to a concert, the artists will be limited to cable length.
    • This concerns me also as I volunteer as an a/v tech at a church. We have some beltpacks we use that arein this spectrum, however our newer Sabine handhelds http://sabine.com/ [sabine.com] of which we use 8 on a regular basis, opperate in the wifi spectrum and though there are several nearby wifi sources (we are in downtown minneapoolis) we have never had an interferance problem. This higher frequency spectum does bring it's own challenges. It is extremly line of sight and when a performer or speaker puts their hand o
  • It has nothing to do with fidelity, it's just wireless internet.

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