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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 Hopefully, this paves the way for more WISPs, bigger hotspots, and replacement of outdated wireless technology that seemed to be the only competitor to DSL and tv-cable for the last mile."

76 of 157 comments (clear)

  1. High effect by martingunnarsson · · Score: 2, Interesting

    With a long range like that I guess your brain will be pretty fried if you sit close to the AP, no?

    --
    Martin
    1. 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.

    2. Re:High effect by interiot · · Score: 3, Informative

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

    3. 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? =)

    4. 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

  2. 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:Good for Bandwidth Co-ops by akb · · Score: 2

      I don't think you've made a case for why the idea is inherently flawed. Certainly what we have now would not scale. But the cable co's seemed to have made a shared medium work. Scalability problems can be addressed by policy makers freeing up spectrum for more nonoverlapping channels.

    3. Re:Good for Bandwidth Co-ops by NoMoreNicksLeft · · Score: 2

      Neither of us have made a good case. Do not forget, that the cable company's "shared network" is actually any number of shared segments, and often hybrid-fiber (rarely pure fiber though?). Wires (and especially fibers) can carry quite a bit more bandwidth than our small slice of RF spectrum.

      I just can't see how wifi can scale past a niche/hobbyist service. It's half as much bandwidth as I would like, if I didn't have to share it. When 500 people within the quarter mile radius start trading mp3's (and god forbid: divx's) it will go downhill really fast.

      There's got to be a better way... but I'll be damned if I can see it.

  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?"
    3. Re:Ho Hum... by Eric+Smith · · Score: 2
      Whoot to Vivato; hopefully they'll get a lower end antenna for fixed wireless clients!
      Why do you think Vivato needs to do this? That's what everyone else sells.
    4. Re:Ho Hum... by crisco · · Score: 2

      I've got to figure out how to use 'disambiguatable' in a conversation with my boss, I might be able to get a raise out of it.

      --

      Bleh!

    5. Re:Ho Hum... by akb · · Score: 2

      Everything is great until its not great, but what's your point? Oversubscription doesn't have much to do with the antenna technology.

  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 g4dget · · Score: 2

      The amazing thing about Vivato's stuff is not that it delivers broadband over a few miles distance, but that it does so within the regulatory confines of 802.11b and without manual aiming of antennas. If you just want to deliver broadband over long distances, there are lots of ways of doing that.

    2. 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.
    3. 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.
    4. Re:Low-tech alternative by Tenebrious1 · · Score: 2

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

      Awesome! I could use one, to fry those damn cats that are howling all night in the alley.

      --
      -- If god wanted me to have a sig, he'd have given me a sense of humor.
  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
    4. Re:Is it too powerful? by ruiner13 · · Score: 2
      "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."

      Not only that, but from what I can remember, I think bluetooth uses the same frequency bads. Not only will it have the ability to bring your home WiFi range down, it can make sure your computer is so distracted by they all-powerful broadband signal you won't be able to sync your cell phone or BT enabled PDA to your computer anymore. I gueds we'll see how this turns out...

      --

      today is spelling optional day.

    5. Re:Is it too powerful? by Hanzie · · Score: 2

      What exactly did dave do? I'm in nearly the same boat.

      Thanks.

      --
      ********* sig: If you don't like the law, get filthy stinking rich, and buy a better one.
  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. Will 802.11b drive IPv6 and IPSEC use? by Anonymous Coward · · Score: 2, Insightful

    I need an alternative source of domain packets!

    The quality of 802.11b security implies the need to lock down the bandwidth with something.

    Could this turn into the killer app for IPv6/IPSEC?

  10. 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.
  11. 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 brianvan · · Score: 2

      Actually, from what I've heard, they use radar to help commercial airplanes navigate. Furthermore, there are few crucial military domestic uses of radar other than national airspace security - that is, we need it to see if someone's sending over bombers to New York or Miami.

      I would argue that, in this case, giving priority to consumer telecommunications would result in killing people. Not the other way around.

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

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

  12. 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

    1. Re:My child has grown a third leg . . . by squaretorus · · Score: 2

      My physics sucks - anyone got a decent overview of the relative densities coming from Mobile phone masts and these things?

      Recently a mobile phone mast was stopped from being erected on my street due to 'concerns over radiation levels' despite the background radiation being some 100x as strong in peoples homes.

    2. Re:My child has grown a third leg . . . by dattaway · · Score: 2

      Don't need physics to understand. Look at the cell antenna's ratings if you were to buy one. Beam pattern and power are what you choose from. They measure them in kilowatts and directional gain.

      Your microwave puts out a kilowatt. If its a good one.

      Its cold this winter. Are you sure a few kilowatts in your back yard are that bad?

    3. Re:My child has grown a third leg . . . by squaretorus · · Score: 2

      Who doesn't need physics to understand thins? Me? I beg to differ. I did a couple of years of Physics at uni and I dont have a quick intuitive way to suss the potential effects of this kind of kit.

      My microwave may 'put out' a kilowatt but whats the apparent energy at 10m, 100m? I have a sneaky recollection that physics has some equations for that kind of shit! I've just forgotten them. They tended to involve squares and cubes and roots!

    4. Re:My child has grown a third leg . . . by nsushkin · · Score: 2, Interesting

      Your microwave doesn't put "out" a kilowatt. The kilowatt stays inside the microwave. Actually, the energy is being transferred only when there is some food containing water inside the microwave. And even then, you have to apply extra effort (rotate the food and the tranceiver) to transfer more energy to the food.

      The radiation is shielded on 5 sides of the oven box by the metal case and the door also has conductive shielding. So, even if you place parts of your body next to the microwave, you won't be exposed to the radiation.

      I read somewhere that they placed people inside big microwave ovens and applied moderate amounts of power. The test subjects experienced a warm fuzzy feeling...

    5. Re:My child has grown a third leg . . . by Alsee · · Score: 2

      Your microwave doesn't put "out" a kilowatt. The kilowatt stays inside the microwave.

      Absolutely right. I just want to clean up a detail...

      And even then, you have to apply extra effort (rotate the food and the tranceiver) to transfer more energy to the food.

      No extra effort is needed. The reason they rotate the food is to even out the heating. Microwaves tend to create hot spots and cold spots in the food. Either way the energy transfer is about the same.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    6. Re:My child has grown a third leg . . . by Eric+Smith · · Score: 2
      Who doesn't need physics to understand thins? Me? I beg to differ.
      The reason you don't need to know physics to understand it is that it can be explained by simple geometry. If you have a 1W radiator (antenna) that is omnidirectional, only a small amount of power will be radiated in any given direction. So when the AP is communicating with a specific node, most of the power is wasted.

      If you use a directional antenna, allmost the transmit power is sent in one direction, so if that's where the receiver is, the same 1W gets more power to where it's useful.

      A phased-array antenna can be directional to an arbitrarily chosen direction, so what the Vivato AP does is readjust the phased-array direction for each client.

      My microwave may 'put out' a kilowatt
      As others have pointed out, it doesn't do that, but assuming it did...
      but whats the apparent energy at 10m, 100m? I have a sneaky recollection that physics has some equations for that kind of shit!
      The inverse square law. This was pretty obvious to me years before I took physics. Microwaves aren't doing anything unusual, just think about a light bulb. If you put a sheet of paper 1 foot from a light bulb, it will collect 4 times as much light as if you put the paper 2 feet from the light bulb.
    7. Re:My child has grown a third leg . . . by gorilla · · Score: 2

      Also the kilowatt is a nominal figure. In actual usage, depending on the model, output can be 8.3% to 22% below the nominal figure. This is why the instructions on your tv dinner always say 'microwave ovens vary'.

    8. Re:My child has grown a third leg . . . by Alsee · · Score: 2

      There are maxima and minima of energy, corresponding to nodes and crests created by the electromagnetic wave

      Exactly right. You get standing waves, hot spots and dead spots.

      the food might not be located at a maximum of the wave oscillations

      In a microwave the maxima and minima are about 1.2 inches apart (3cm). It you're cooking anything bigger than a marshmellow you're going to hit a maxima no matter where you put it. The rotation just smooths out the cooking on the inch-scale.

      -

      --
      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    9. Re:My child has grown a third leg . . . by dattaway · · Score: 2

      Your microwave doesn't put "out" a kilowatt.

      You haven't seen my microwave have you? Waveguides make wonderful antennas...

  13. 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 Graymalkin · · Score: 2

      The parent post was regarding consumer access, not public service access like PD and FD. The major reason hospitals don't want you running around with an Airport card in your laptop is because their monitoring systems use the same frequencies. Nurses not knowing a dude in the intensive care ward is having a heart attack because some jackass is sitting in the lobby playing Quake on his laptop would be a very bad thing.

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

      Last I checked, playing Quake, even on a laptop, didn't make someone a jackass.

      I think you may have missed my point. I was expressing amusement that public service's are finding use for a consumer system that is regulated such that it won't 'interfere' with, or be useable in, the function of public services. The correct conclusion to reach is that it would have been much better to allow the services to co-exist and benefit eachother (more so the public service sector).

    4. Re:Alot of problems solved, new ones created. by Waffle+Iron · · Score: 2
      The major reason hospitals don't want you running around with an Airport card in your laptop is because their monitoring systems use the same frequencies.

      If they've got mission critical wireless systems, WTF don't they run them on their own exclusive licensed frequencies?

    5. 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.
    6. Re:Alot of problems solved, new ones created. by BeBoxer · · Score: 2

      PD's, FD's, Hospitals, etc. are all considered to be zones absolutely off limits to any such interference this would cause

      So it's illegal to use 802.11b, a 2.4GHz cordless phone, or a microwave oven in the same region as a fire department, a police department, or a hospital? Quite frankly, I think you're wrong and yours is the first such claim I've heard regarding the use of unlicensed spectrum. Please provide a reference, as it appears you believe that the FCC was quite irresponsible in allowing retailers to sell such dangerous devices to the general public.

  14. 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

  15. 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.
  16. 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!

  17. 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.

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      -- @rjamestaylor on Ello
    2. Re:Ewige Blumenkraft by Graymalkin · · Score: 2

      I SPECIFICALLY said that the access point of the equation is not the problem. The problem exists on the client end without phased array antennas. If you have fifty people all in the same area with their cheapo dipole antennas chattering away on the network the whole thing becomes inusable. It doesn't matter if the head end has some cool steerable spot beam. Having a head end switch from Vivato is like plugging a bunch of nodes into a hub and then plugging that hub into a switch to talk to other hubs.

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      I'm a loner Dottie, a Rebel.
    3. Re:Ewige Blumenkraft by Alsee · · Score: 2

      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.

      This is not a problem. Lets seperate it into three problems. (1) The AP sending packets to the mobiles. (2) The AP detecting packets from several mobiles. (3) Mobiles interfereing with each other.

      The phased array is behaves like several access points with seperate high gain directional antennas. This works on both transmission and reception. The the AP can beam simultaneous packets out, so (1) does not cause collisions. The AP can read simulaneous packets from different directions, so (2) does not cause collisions.

      I think you are worried about (3). If you have a fixed number of people in a fixed area it makes no difference weather or not they are on the same AP.

      Putting a given set of people onto the same AP only matters to the the AP, and the phased array solves that. (Unless they all stand in a line pointed at the AP :D)

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      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    4. Re:Ewige Blumenkraft by Wesley+Felter · · Score: 2

      802.16 looks like it ought to support more clients/base station than 802.11 because it uses TDMA instead of CSMA/CA. This Vivato antenna has the advantage of being compatible with existing equipment, though.

    5. Re:Ewige Blumenkraft by Graymalkin · · Score: 2

      Sweeping a broadbast between different nodes doesn't do much good on their end where all the static from other connections is an issue.

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      I'm a loner Dottie, a Rebel.
  18. What about the client? Does it get a 4 miles too? by kneel · · Score: 2, Interesting

    Makes sense that you can build a big-ass AP that will provide a large 802.11 blanket, but how is my laptop's little antenna going to talk back to it?

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    indierock / punkrock band photos and more... http://www.digitaldefection.net

  19. 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.

  20. What about something that will work through trees? by tommck · · Score: 2

    I don't care about all these cool _wide_ _open_ _land_ solutions!

    What about all the people who can't even see their neighbor's house? I want to set up a WISP in my neighborhood, but I have no direct line of site to anybody.

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    ---- It puts the lotion on its skin or else it gets the hose again. It does this whenever it's told.
  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.

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    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. Non-ionizing radiation by guacamolefoo · · Score: 2

    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

    I understand that you are trying to be funny, but I see sooooooo much cell tower ignorance at zoning hearings.

    First of all, people (including zoning officials) do not understand that radiation levels are not something that can keep out cell towers. That is an area which has been pre-empted by federal law.

    Second, they do not understand that cell phone radiation is not ionizing radiation. It cannot break chemical bonds and cause genetic mutations. It could cook you if you stood close enough and it broadcast at a high enough power, but it cannot cause cancerous changes. These people hear "radiation" and think "Godzilla" not "reading lamp". It's just blatant science ignorance.

    GF.

  25. certifications... by morcheeba · · Score: 2

    Actually, the FCC doesn't limit raw power, it limits power per solid angle steradian (actually, it's usually max power/square area at a certain distance -- effectively the same, but no confusion over near-field effects of the antenna). Just like using a magnifying glass to concentrate sunlight, it can be just as dangerous to concentrate RF power - and the FCC knows this.

    Still, the increased bandwidth due to multiple beams will be very helpful in overcrowded environments.

  26. Stupid, they better fix the guns. by twitter · · Score: 2
    Thanks for the NYT article, which everyone in the world can read. I can just imagine this:

    Dear Tiger Direct,

    Do you offer volume discounts for 802.11 equipment? We are interested in many hundreds of thousands of these and will gladly pay in counterfit US dolars, oil or gold.

    Sincerely, your friend.

    General A. Henchman
    Iraqui National Air Defense
    Bagdad, Iraq.

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    Friends don't help friends install M$ junk.

  27. 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.

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    Friends don't help friends install M$ junk.

  28. Re: work through trees by twitter · · Score: 2

    Try setting the antea up on top of the tree. It's a free no paint needed tower.

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    Friends don't help friends install M$ junk.

  29. Re: but... with 802.11g you get 54 Mbps by Alsee · · Score: 2

    That has nothing to do with phased antennas arrays. A phased array has more than one antenna. When you use multiple antennas your bandwith goes up whatever protocol you use. The trick is that phased array antennas are all in (nearly) the same spot and cooperate in a sophisticated manner.

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    - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
  30. Re: work through trees by MikeBabcock · · Score: 2

    Antennae on trees tend to sway quite a bit and if you're dealing with directional ones, its not going to work.

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    - Michael T. Babcock (Yes, I blog)