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FCC Approves 802.11b Phased Array

n6zfx writes "802.11b Networking News is reporting that vivato received FCC approval for the 802.11b AP that has a range of 4 miles... This was discussed recently here on slashdot -- There were comments that it might not be totally legal. Hopefully, this paves the way for more WISPs, bigger hotspots, and replacement of outdated wireless technology that seemed to be the only competitor to DSL and tv-cable for the last mile."

39 of 157 comments (clear)

  1. Good for Bandwidth Co-ops by Skrap · · Score: 5, Interesting

    This will be especially relevant for Bandwidth co-ops.


    The biggest obstacle to creating a co-op is having enough potential subscribers to convince the telcos that it will be worth their while to run the dry pairs the "last mile" from the DSL POPs to the houses. I am guessing that this technology will begin to allow metropolitan bandwidth co-ops to have an effective solution outside of the telco's control. Please, oh please, let broadband not suck forever.

    1. Re:Good for Bandwidth Co-ops by NoMoreNicksLeft · · Score: 3, Insightful

      You know, there were several reasons that 10base2 only allowed 30some hosts per segment, but a not insignificant one was that collisions don't increase linearly as you add hosts.

      Despite what some believe, 802.11 is basically a single pipe, shared with everyone. This simply isn't the solution you're looking for, even if it is the only one available.

      Reminds me too much of idiots who use USB for cd burners and the like. Then they wonder why the mouse cursor is unresponsive.

      I'm not a troll... I do sympathize. I want to figure out how to get broadband to everyone too. But this isn't it.

  2. Re:High effect by AndrewMcG · · Score: 4, Informative

    Actually, that's why it needed certification. It won't, it has very little different output to your laptop card. It works by actively steering antenna beams at associated users. Very cool for ISPs and big campuses.

  3. Ho Hum... by User+956 · · Score: 5, Insightful

    Vivato's bases reach groups of users on existing laptops and other computers, with an operating range up to 7 kilometers outdoors, the company claims. Software controlling the antennas detects Wi-Fi clients in the area and adjusts the signal across the array many times per second.

    Which is great, except when they overbook in order to maximize revenue, much like cell phone companies. Then we have spotty, intermittent coverage serving only a percentage of paying customers, as the system struggles to keep up.

    Yay technology!

    --
    The theory of relativity doesn't work right in Arkansas.
    1. Re:Ho Hum... by Effugas · · Score: 5, Informative

      A few years back, a company came to my school to give a talk about SDMA -- Spatial Division Multiple Access. It was essentially based on the concept that, duh, a single cell phone is only one position, so the tighter a beam you could direct / detect from the phone, the more points could use the same frequency.

      The cool thing about SDMA is that as your load increases, so too (to a limited degree) does your available bandwidth. As long as people are relevantly separated from eachother, their physical positioning relative to other hosts adds disambiguatable bandwidth. It ain't perfect -- node to node crosstalk is a real problem, since your wifi cards are omni -- but they're talking about such range that there's lots and lots of omni hexes to expand through.

      Whoot to Vivato; hopefully they'll get a lower end antenna for fixed wireless clients!

      Yours Truly,

      Dan Kaminsky
      DoxPara Research
      http://www.doxpara.com

    2. Re:Ho Hum... by Scutter · · Score: 3, Insightful

      Disambiguatable? ;-)

      --

      "Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
  4. Low-tech alternative by icantblvitsnotbutter · · Score: 5, Informative

    A company in Sweden conducted tests with a stratospheric balloon. They broke 300 km (187+ miles).

    Not entirely salient, but a reminder that there's more than one way to skin a cat.

    1. Re:Low-tech alternative by perfessor+multigeek · · Score: 3, Interesting

      I'm a helios man myself. Once they get those puppies finalized, you'll see small towns able to cover footprints larger then most states. Specifically, this will be much more practical in mountainous areas or simply those with lots of deep ravines.
      In Montana they've had trouble because people tend to build in narrow valleys (more water, less wind, etc.) and thereby are choosing the areas with the *worst* possible radio wave accessability. The higher you go, the less that matters.
      Rustin

      --
      Data is the lever, rigor the fulcrum, brains the force that drives it all.
    2. Re:Low-tech alternative by medscaper · · Score: 4, Funny
      there's more than one way to skin a cat.

      Ok, Swedish or not, any company that can skin a cat with a balloon from 300 km away has my complete and total attention.

      --
      Any sufficiently well-organized Government is indistinguishable from bullshit.
  5. Is it too powerful? by JakiChan · · Score: 5, Insightful

    So, if the Starbucks a few blocks over installs this, is it going to stomp all over my home network? I mean a WiFi hotspot with a 4 mile radius is great, but hopefully wouldn't affect home users. That'd be like some new cellular tower killing my cordless phone...certainly not appreciated.

    --
    "Where quality is like a dead stinking rat - you just can't miss it."
    1. Re:Is it too powerful? by Uller-RM · · Score: 5, Informative

      I live in Portland, OR, home of PersonalTelco - a fairly well known volunteer group for WiFi access. We have more nodes listed on nodedb for the Portland metropolitan area than nearly any STATE - and take that to all states if you count all of Oregon.

      We had a big landmark case here a while ago that's exactly what you're fearing. PersonalTelco's been providing a totally free 11Mb connection to Pioneer Courthouse Square (a major hotspot in downtown Portland), and the Starbucks on one corner of the square tried to compete with them, broadcasting their pay-to-use TMobile service on the same channel.

      Starbucks ended up having to back down - they now broadcast on channel 11, and PT on 6.

      PT's a great group to get involved with - not only do they have regular meetings and stay active with local politics, they also organize a lot of things like group buys on antenna connectors and workshops on Pringles can waveguides.

    2. Re:Is it too powerful? by g4dget · · Score: 4, Insightful
      Over the same area, it should actually reduce interference compared to trying to cover the same area with regular access points.

      Think of it this way. With a normal access point, it's like lighting a stage with diffuse lighting: there ends up being light everywhere. This access point is intended to be like a bunch of spotlights on a dark stage: only the areas where it is aimed are actually lit up; the rest of the stage remains in darkness.

    3. Re:Is it too powerful? by rjamestaylor · · Score: 3, Interesting
      • Over the same area, it should actually reduce interference compared to trying to cover the same area with regular access points.

        Think of it this way. With a normal access point, it's like lighting a stage with diffuse lighting: there ends up being light everywhere. This access point is intended to be like a bunch of spotlights on a dark stage: only the areas where it is aimed are actually lit up; the rest of the stage remains in darkness.

      That's a pretty accurate analogy. Having been program director at a (day time) 50kWatt AM radio station with directional restrictions I've seen powerful radio frequency radition effectively "spotlighted" to cover a quite-convoluted coverage map. Some areas being well lit and other, nearby areas being practically dark. It took four hefty antennae to accomplish the coverage pattern carved out by the FCC restrictions on our signal, but it worked very well.

      As an aside, I also saw the sad effects of this directional power on a new apartment bulding constructed on a hill less than 400 yards from the antennae in the direct path of the focused radiation. First, realize that once the FCC grants approval the radio station has a right to the frequency, more so than those who experience interference from the signal. Especially more so than new developments begun well after the station has been approved and begun broadcasting. Anyway, the poor schmucks could hear our broadcasts on the toasters (!). CD players wouldn't play (but they worked in the stores a couple miles away), forget cordless phones--forget corded phones! These people were living in the spotlight, alright. Before the apartments were completed, the foreman came to visit me at the station--the fire alarm couldn't call out to the alarm company due to interference. I called my broadcast engineer (a local area college professor who loved radio and worked more for the fun than anything else) as I hummed the tune "The Fool on the Hill." Dave came out and helped the construction crew insulate and filter the building so people wouldn't die and he even helped the toaster problem. Dave helped other nearby businesses and schools located in the direct path of the signal to filter there systems--one school couldn't use their public address system because it just played our station when activated. . .Dave fixed it.

      Boy, I miss those days! Sometimes. . .

      --
      -- @rjamestaylor on Ello
  6. Phased Arrays Won't Impress Me... by Quaoar · · Score: 4, Funny

    ...until Pink Floyd uses them in concert.

    --
    I'll form my OWN solar system! With blackjack! And hookers!
  7. wireless by katalyst · · Score: 3, Interesting

    Interesting...... Gives rise to lots of new avenues for hacking too. Imagine to not have to be PHYSICALLY wired in. Instead... use your laptop to connect to your target server's airport and VOILA! Maybe companies will sheild their office complexes, so that a guy sitting outside the fence can't mess around with their data.
    Exciting possibities....

    --
    |/________
    |\A|ALYS|
    1. Re:wireless by tigress · · Score: 3, Informative

      This is already happening. Didn't you read any of the stories about wardriving?

      The "standard" 300m outdoor-range of most APs are more than enough.

  8. Destructo-Ray? by zumbojo · · Score: 5, Funny

    I could have sworn that the last time I heard "phased array" and "4-mile radius" together in one sentence something in some movie blew up.

    1. Re:Destructo-Ray? by Asprin · · Score: 3, Funny
      --
      "Lawyers are for sucks."
      - Doug McKenzie
  9. Re:High effect by interiot · · Score: 3, Informative

    Two watts? Are you on crack? Try 600 - 125 milliwatts.

  10. Re:High effect by tigress · · Score: 3, Interesting

    I stand corrected. I based my comment on third party information, from someone who was supposedly wireless certified. Still 600mW is a lot more than what an AP is allowed to output (100mW) around here, and you don't usually press an AP against your ear, now do you? =)

  11. Re:High effect by tigress · · Score: 5, Informative

    Actually, on second thought...

    Peak power output corresponds to 2 Watts or 2000 milliwatts (mW) which averages to 250 mW of continuous power. An analogue phone (AMPS system) has peak power limited to 600mW.

    Source

  12. Sprint broadband by g4dget · · Score: 3, Insightful
    and replacement of outdated wireless technology [Sprint broadband]

    Well, Sprint Broadband works, it delivers >3Mbps, it's fairly easy to install, and it costs $50/mo. And I doubt it's a money losing venture, otherwise they'd have discontinued the service entirely rather than just not taking new signups.

    If companies will compete with Sprint broadband using Vivato technology, that would be great. But with the Vivato APs being released in 2003, I think it's at least another year away until you are going to see viable commercial broadband services based on it springing up.

    1. Re:Sprint broadband by praedor · · Score: 3, Informative

      Last I heard/read, Sprint broadband was no longer accepting new customers (This was almost a year ago I read this on their site). If you have it now it is only because you got in before the locked down the system and stopped accepting new users. Doesn't bode well for its future does it?

      --
      In Bushworld, they struggle to keep church and state separate in Iraq as they increasingly merge the two in America.
  13. Guns before butter by release7 · · Score: 5, Interesting

    I'm afraid killing people takes precendence over informing them. The Pentagon reports that wi-fi networks interfere with their radar and further rollout of the technology must be curtailed. Read this article.

    --

    <a href="http://www.joblessjimmy.com">Work is dumb and so is Jobless Jimmy.</a>

    1. Re:Guns before butter by Anonymous Coward · · Score: 3, Funny

      I hope a HARM missle does not home in on my Powerbook.

  14. My child has grown a third leg . . . by pariahdecss · · Score: 4, Funny

    I am all for the propagation of this technology. I live in an area with no broadband access whatsoever . . . .just don't put the radiating tower in my backyard . . .my kids are weird enough without growing extra appendages

  15. Alot of problems solved, new ones created. by iq+in+binary · · Score: 5, Interesting

    4 miles? That's all fine and dandy, but think of the implications aside from being able to connect in "pocketed" areas.

    Too many "off-limits" zones in the suburbs of major cities for this to be any good. Considering the fact that upwards of %80 of the people that'd benefit from this live in such suburbs. PD's, FD's, Hospitals, etc. are all considered to be zones absolutely off limits to any such interference this would cause (suburbs are totally PACKED with these, There are 3 PD's and 2 FD's, as well as 2 Hospitals within a 4 mile radius of my house). That's FCC regulation that's been around since the '30s, and they're sure as hell not going to change them now.

    Given the method they'd have to use to make sure they aren't broadcasting in that area, you end up with 1 or 2 degree swaths of no service areas eminating from the tower. May not sound big, but after a mile or so it gets to be the width of a city block.

    I'm all for this, but a better solution would be to use smaller and cheaper arrays. Just find a way to lower the latency and it'd be even better.

    --
    Of all the Universal Constants, here's one I know: Nice guys finish last ;)
    1. Re:Alot of problems solved, new ones created. by Graymalkin · · Score: 3, Informative

      What you describe was wat Metricom/Aerie/Whoever tried to do with Ricochet. Instead of a bunch of towers covering large cells they used their little repeaters to make micronetworks. Instead of having a huge swath of city not covered by a spot beam they just neglected to stick repeaters up in that area.

      --
      I'm a loner Dottie, a Rebel.
    2. Re:Alot of problems solved, new ones created. by Alsee · · Score: 3, Informative

      PD's, FD's, Hospitals, etc. are all considered to be zones absolutely off limits to any such interference this would cause... ...better solution would be to use smaller and cheaper arrays.

      The point of the phased array is that it causes far less interference. It can get coverage to far more area while staying within the exact same limits to hospitals, PD's and FD's. It also gives you far more control of the coverage. Even if you have a "1 or 2 degree swath" on the far side of a hospital you can cover it with a second tower 3 miles away in a different direction.

      The current implementation uses a fairly localized phased array to create beams. If they were to coordinate widely separated antennas they could do much better than beams, they could give pinpoint coverage. Almost like placing an ultra-weak antenna on the target's shoulder. It also becomes possible to actively zero-out the interference to hospitals with a pinpoint inverse signal.

      They aren't up to pinpoint coverage level I described, but it will come. The current phased arrays are still far better than regular antennas.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  16. Security issues addressed? by InfiniteWisdom · · Score: 4, Interesting

    802.11 has been shown [1] to be completely insecure... have these security issues been fixed? From my reading of the paper, all that really needed to be done to fix most of the issues was to switch from OFB mode to CBC or CFB [1] Nikita Boristov, Ian Goldberg, David Wagner. Intercepting Mobile Communications: The Insecurity of 802.11. SIGMOBILE 2001. http://www.berkeley.edu/isaac/mobicom.pdf

  17. Ken Biba? by sczimme · · Score: 4, Interesting


    Given the qualifications and history of Ken Biba listed in the article

    Biba started in security and networking R&D 30 years ago with Mitre Corp. and was a member of the Advanced Research Projects Agency Transmission Control Protocol (TCP) Working Group

    I wonder if he is the same Ken Biba that worked on/devised Mandatory Access Control (MAC) and the Biba Integrity Model.

    There is a good description of MAC here, and an explanation of the Biba Integrity Model here.

    --
    I want to drag this out as long as possible. Bring me my protractor.
  18. AMPS by wowbagger · · Score: 4, Interesting

    An AMPS phone may be limited to 600 mW in the systems in Australia, but the actual limit on a Power Class 1 Phone is 5 watts. That is one of the reasons that replacing the AMPS system with (CDMA|TDMA) systems in the US has been very slow - a Class 1 phone can contact a base station many tens of miles away, which is IMPORTANT in much of the US - when you are in western Kansas, Nebraska, Wyoming, Montana, Utah ... you get the point.

    That was part of why the old phones where so large - a 5 watt 100% duty cycle power amp isn't tiny. (the other reason was that since AMPS requires the phone to transmit and receive at the same time, the phone had to have an RF duplexer in it - not a small item, even at 800MHz. TDMA phones don't transmit and receive at the same time, hence they don't need the duplexer).

    That's one of the reasons I tell people to look for the old phones at garage sales - get the phone and you have a dandy 911 phone - you WILL get a connection!

  19. Ewige Blumenkraft by Graymalkin · · Score: 3, Insightful

    So how exactly do people with pie in the sky Wi-Fi plans intend to overcome 802.11b's inherent scalability problems? How many people can one AP REALLY serve?

    From my experience I'd say that answer to that question is not very many. Having more than a couple people on a single AP is a recipe for pain and suffering. As the number of users on an AP increases so does the chances of packet collisions. As collisions increase the viability of the network decreases and you eventually reach a collapsing point where the network is unusable. A corollary to that rule then would be the larger your coverage area the higher a chance of collisions and thus a higher chance of the network collapsing.

    You run into a similar problem with 802.3 which is solved by switching the network. With a wireless network you don't have the ability to add a switch in the middle of the network to keep the number of collisions down to a minimum. You're only got a bunch of nodes waiting their turn to talk. Switching channels isn't an option because APs can only serve particular channels.

    With a coverage area of four miles then, the number of potential collisions on a channel is pretty high because your entire customer base could be in that four mile coverage area. Sweeping a broadbast between different nodes doesn't do much good on their end where all the static from other connections is an issue. On current networks you've got a small number of users because your coverage area is pretty small so problems aren't evident. You don't have problems on a wired network with only a 5 port hub either.

    --
    I'm a loner Dottie, a Rebel.
    1. Re:Ewige Blumenkraft by rjamestaylor · · Score: 4, Informative
      What part of "Wi-Fi Switch" did you not understand? From the site:
      • Vivato's Wi-Fi switches deliver the power of network switching with Vivato genius radio antennas. Vivato's switches use phased-array radio antennas to create highly directed, narrow beams of Wi-Fi transmissions. The Wi-Fi beams are created on a packet-by-packet basis. Vivato calls this technology PacketSteering(TM). Unlike current wireless LAN broadcasting, Vivato's switched beam is focused in a controlled pattern and pointed precisely at the desired client device. These narrow beams of Wi-Fi enable simultaneous Wi-Fi transmissions to many devices in different directions, thus enabling parallel operations to many users - the essence of Wi-Fi switching. These narrow beams also reduce co-channel interference, since they are powered only when needed.
      • Vivato's Wi-Fi switches significantly increase the range of Wi-Fi. Rather than transmit the radio energy in all directions, Vivato's PacketSteering concentrates the same amount of energy into a narrow, long beam. This beam is effectively a high-gain antenna that is formed for the duration of a packet transmission. The result is extreme range - extending the reach of Wi-Fi from tens of meters to kilometers.

        Another key attribute of switching is preserving compatibility with standard client devices. Vivato's Wi-Fi switches deliver increased capacity, range and security to standard Wi-Fi clients based on the IEEE 802.11b, 11a or 11g standards. With increasing capacity and range, Wi-Fi switches are more scalable than Wi-Fi traditional micro-cellular implementations and are managed in much the same way as Ethernet switches for easy adoption and widespread deployment.

      --
      -- @rjamestaylor on Ello
  20. Gotta love the name... by goodEvans · · Score: 4, Funny

    The Terminator: The .45 Long Slide, with laser sighting.
    Pawn Shop Clerk: These are brand new; we just got these in. That's a good gun. Just touch the trigger, the beam comes on and you put the red dot where you want the bullet to go. You can't miss. Anything else?
    The Terminator: 802.11b Phased Array rifle in the forty watt range.
    Pawn Shop Clerk: Hey, just what you see, pal.

  21. Phased Arrays by grub · · Score: 3, Funny


    Whoa... Every time I hear that term it's on Star Trek and in regards to some huge weapon of mass destruction.

    /me wraps his head in another layer of tinfoil.

    --
    Trolling is a art,
  22. Smarter, not harder (same effect, better aims) by Anonymous Coward · · Score: 5, Informative

    Please guys, this techonology is NOT about splattering megawatts all over town!

    It is about aiming a low power beam in the right direction using a smart antenna AND that same smart antenna is a better listener.

    It's a high-tech equivalent of a parabolic antenna and it is adjusted to radiate the same power at a distance as a normal omnidiretional antenna would do. That's what the FCC require in order to approve an antenna.

    It's a common mistake to think that range=power. Note that this is a two way operation.

    You also have to be able to hear the other guy, right? That takes good listening skills = a directional antenna.

  23. Phased Array? by sdjunky · · Score: 5, Funny

    Now if Only I can calibrate the deflector dish to use the dilithium crystals to create a Tachyon pulse...

    Where is Spock when you need him?

  24. Sprint costs. by twitter · · Score: 3, Insightful
    I just happened to have a brochure of Sprint's Vision plan in front of me. There is no $50/month data plan, however $40/month will get you a big fat 20 mega bytes, with each additional kilobyet costing you $00.002. or two freaking dollars per megabyte. For $100/month the service is "unlimited." I imagine much of that money will go directly to the FCC as a result of Bill Clinton's big greedy specturm auction. I don't know about you, but I don't have that kind of money to further fund the Feds.

    It's shocking that the new administration is following the greedy, ignorant policy of it's predecesor. If such services flop, those who opposed the specturm auctions can say, "I told you so," and that will be that. It's not like the telecomunications has been a stable source of employment for most of the people working there. If the government forgives the auction debts, it will ammount to a huge bail out of big corporate interests. That's bad because it give an advantage to those who bid irresponsibly and continues the ineficient specturm use but at least it will provide service to people at something closer to its cost. If the government legislates 802.11 out of practicality, it will be a huge scandal as the only reason will be to prevent new entrants from ruining these silly third generation services. Yet this third option is the one that keeps comming up. Keeping the public from building their own communications networks, which are technically possible, ammounts to a denial of first amendment free speech rights.

    Bandwith scarcity is a lie and services that operate on that principle, metering out kilobytes of data, are a rape.

    --

    Friends don't help friends install M$ junk.