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New Phased-Array AP Boosts 802.11b Range

Posted by timothy on from the bring-it-on-quickly dept.

ttul writes "Vivato, a well-funded wireless startup, today came out of stealth mode to announce its "WiFi" switch product, a super high performance 802.11b access point that uses an array of hundreds of antennas to provide wide-area coverage to standard 802.11b clients. See stories at Wired, and The New York Times. Vivato's new AP completely changes the economics of WiFi especially for providers such as FatPort and WayPort, who now have the technology to deliver 11Mbps to your laptop even if you're miles from a location -- it's the Jetson's, folks!"

12 of 203 comments (clear)

  1. Headline news? by cmeans · · Score: 5, Funny

    What is this, CNN's Headline news?..all the news, the same news, every half hour!

    --
    Give a hand, not a hand-out.
  2. Is this a good thing? by JohnA · · Score: 5, Insightful

    What if I don't want this super-array to interfere with my local WLAN? It appears that this technology has the potential to create a "mine is bigger than yours" arms race among WiFi users.

    1. Re:Is this a good thing? by Merkins · · Score: 5, Informative

      Did you read the articles ?

      The actual output of this thing is on 30mw. It just increases range by locking on to it's clients and adjusting itself to aim more directly at them. because of this, it will actually cause less general interferance than a standard garden variety AP

      --

      Learn to Improvise
    2. Re:Is this a good thing? by Beryllium+Sphere(tm) · · Score: 5, Interesting

      Sometimes the FCC regulates how directional you're allowed to be.

      The magic word here is EIRP, Effective Isotropic Radiated Power. It's how bright you look to someone who's in line with your RF beam. Even if your total power is low, and you're avoiding interference with people who aren't in line with your directional beam, high EIRP can cause problems for innocent bystanders anywhere on the line between you and your intended recipient.

      EIRP increases with transmitter power and with antenna gain (== directionality).

      This is why it's technically illegal to put a better antenna on your cordless phone, and why the phones don't come with easily replaceable antennas.

      Now, if these people are really smart, they could set their beamforming code to plant a null on any 802.11 network that's not a customer, in which case they'll avoid interference.

      Fred KC7YRN

  3. what about the not-slow people by hfastedge · · Score: 5, Funny
    From the wired article:
    "We think it'll work reasonably well at pedestrian speed," said CEO Ken Biba,


    This company will surely fail. Its technology isnt taking into account laptop joggers, laptop motorcyclists, laptop unicyclists. And leisure, urban helicopterists and skydivers...
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  4. Asymmetry and number of users by Anonymous Coward · · Score: 5, Interesting

    The use of a phased array antenna for transmission to the client is nice, but I wonder if it requires the client to be modified to run special tracking software that sends back multipath information to the basestation to enable it to tune its beam.

    This makes me think that the data-link would probably end up being asymmetric --- high data rate down to the client but not so good coming back. Not only would the upstream rate be partially consumed by the multipath measurements, but also the single antenna on the client would have a harder time beamforming out to the receiver array.

    The power constraint is probably on the total output from one array and as such, the number of users that any one of them can support is probably fairly limited. This suggests that things can get quite interesting if we put a bunch of these in close quarters. The optimal solution would be for the AP to collaborate and divide up the users among them not by simple distance (voronoi regions) but by effective distance involving the specific multipath environment! Otherwise interference would be a serious problem.

  5. Why...... by jwilcox154 · · Score: 5, Informative

    use a Phased-Array AP to Boost the 802.11b Range, when you can use a Pringles Can as the Wi-Fi Antenna to Boost the Range? ;)

  6. Question.... by hawkbug · · Score: 5, Insightful

    Maybe somebody can answer this for me, but I see a major problem with current wireless technology. I currently have an 802.11b access point in my home. I love it, and it gets great range - in fact, so great it goes clear over onto my neighbors property. I had my laptop outside (probably looked like a dork walking around running a constant ping on my thinkpad), and I was able to walk clear onto their property and get a great signal. At first I was impressed... then I started to think about my neighbor. Wouldn't this be a problem for them if they wanted their *own* access point for their network?? I would think that my access point also interferes with 2.4ghz phones in the area. As an example, I had to sell mine because they quit working the second I got this thing. So, if you could expand the range of 802.11b to *miles* - isn't that really going to screw over Joe Blow who wants his own wireless network that just happens to be within range of a provider mentioned in the story???

    1. Re:Question.... by ealar+dlanvuli · · Score: 5, Funny

      (probably looked like a dork walking around running a constant ping on my thinkpad)

      My neighbor got worried enough to poke their heads out and ask me what I was doing when I mapped my network range :0

      It was... fun... explaining I was accessing the internet.

      --
      I live in a giant bucket.
  7. Why should they? by Perianwyr+Stormcrow · · Score: 5, Funny

    Hell, even I don't read it anymore. I just go into meta-moderation and reply at random to whatever comments come up.

    --

    What we call folk wisdom is often no more than a kind of expedient stupidity.-Edward Abbey

  8. /. Effect by batboy78 · · Score: 5, Funny

    Apparently they didn't get slashdotted this morning, time for round two. Ding Ding Ding.

  9. This is an active phased array... by Newer+Guy · · Score: 5, Informative

    It works much like the active radar antennas that do not move. Here in Santa Monica we have a large phased array of hundreds of fixed antennas aimed at the horizon that are sequentially pulsed on and off to get the familiar 'rotating' pattern of a single rotating radar dish. This design is much more robust then a rotating array as there are no mechanical rotating parts at all...everything is switched by PIN diodes. Military jets also use a variation of this for secure communications. In the jets' wings are switched inductor antennas that are used in a fast frequency hopping scheme over a 50 mhz range. The transmissions can be anywhere within a 50 mhz frequency segment at any given fraction of a second. If the frequency synthesizer at all locations are moving to the same frequency at exactly the same time, the transmisison will sound completely continuous.
    They use PIN diodes to change the taps on an inductor to resonate the antenna over the (wide) frequency range. This way, they can use smaller, lighter, narrower bandwith antennas and rapidly tune them to the exact frequency in use at any given moment.

    All in all, a very slick technology and another example of a civilian use of military technology.