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FCC Rule Cuts Bandwidth For 72-Mile 802.11b 146

Posted by CmdrTaco from the slowing-down-the-bits-and-bites dept.
sonamchauhan writes "This Computerworld article reported a 72-mile 802.11b wireless link (discussed in this Slashdot story). Now a Computerworld followup story is reporting the link power has been reduced by 75% to comply with FCC regulations for the 2.4-GHz band -- reducing the link's throughput from 1 Mbps to 300 Kbps. The owner is reported saying that: "any violation of the power limits was unintentional and resulted from the fact that the personnel working [on it] primarily have expertise in computers and not radio technology.""
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FCC Rule Cuts Bandwidth For 72-Mile 802.11b More

FCC Rule Cuts Bandwidth For 72-Mile 802.11b

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  • ba-bump (Score:4, Funny)

    by unterderbrucke ( 628741 ) <unterderbrucke@yahoo.com> on Saturday December 21, 2002 @05:33PM (#4937485)
    I can't write a comment, I'm leaving for CompUSA to buy all remaining 802.11b transmitters + receivers!

    • Re:ba-bump bump! (Score:5, Funny)

      by t0qer ( 230538 ) on Saturday December 21, 2002 @06:33PM (#4937702) Homepage Journal
      And I gotta get down to 7-11 before they outlaw pringles cans!

      • Re:ba-bump bump! (Score:3, Insightful)

        by spike hay ( 534165 )
        And I gotta get down to 7-11 before they outlaw pringles cans!

        Pringles can antennas are already illegal. They are unapproved by the FCC. I still can't believe that the FCC is unwilling to free up some space in the spectrum. If they could make just one 1-gigahertz wide band in the 10-50 ghz range unlicensed, that would really expand the opportunities for wifi. (That frequency would make it hard to transmit between rooms in houses. The 2.4 ghz is better for that. But it would have no problem going a mile or two over the air with enough power, provided there isn't any fog or anything.)
        • The problem is that there is not just one group (the wifi fans) wanting such bandwidth, they have to split it up between many potential users.
          Sadly the last years more and more bandwidth goes to the highest bidders taking it away from others that could use it for other interessting things.

          Think radio astronomy and HAM users....
          (OK I'm a bit biased as I am a HAM myself....)

          Jeroen

          • 2.4GHz in the US (Score:3, Interesting)

            by MaggieL ( 10193 )
            In the US, the 2.390-2.450 allocation belongs to radio amateurs, who are using at least some of it to receive to weak signals from the AO-40 amateur radio satellite. Owners of unlicenced (Part 15) devices are requred to cease operation immediately if they are causing interference to licenced users, even if their equipment is unmodified, within power limits and type-accepted.

            Signals at this frequency are highly directional, and if you interefere with an amatuer satellite operator, you can expect to hear from them. They know who to talk to at FCC about enforcement, too.

  • Big deal (Score:3, Informative)

    by krog ( 25663 ) on Saturday December 21, 2002 @05:38PM (#4937502) Homepage
    So set up two more of them, and multiplex. Bingo! 1MBit.

    FCC regulations exist for a reason, folks.
    • No. Some/most FCC regs exist for a reason. Others, like the propose anticopy regs, exist for no good reason.
      • All he's saying is that they aren't arbitrary. It's not like they're drawing frequencies out of a hat at the FCC office.
        • "It's not like they're drawing frequencies out of a hat at the FCC office."

          No, it's the names of who gets to buy frequencies (that should be leased rather than sold) that they draw from the hat (although I wouldn't be surprised if campaign contributions caused a few rabbits to be slipped into the hats to push certain applications to the top of the pile).

  • That's still excellent throughput for a wireless connection at that distance.
    • It's about the speed I get with my cable modem. And *my* wireless--admittedly using a cheapo home deal--starts choking when I go to the other end of the next room. :)

  • Easy mistake (Score:4, Informative)

    by geogeek6_7 ( 566395 ) on Saturday December 21, 2002 @05:39PM (#4937511) Homepage
    Its pretty easy to go over the maximum power output, which I believe is two watts. Assuming certain combinations of high-gain antennae and an amplifiers, there is no helping blowing past the FCC regs.

    To find out if you are over, you need to calculate to total db of gain you have, and convert that to watts.

    geogeek

  • Told you so. (Score:5, Interesting)

    by GigsVT ( 208848 ) on Saturday December 21, 2002 @05:41PM (#4937520) Journal
    To all the people that flamed me [slashdot.org] in the previous story for pointing out they were likely violating FCC regs, bite me.

    People just couldn't fathom that college professors [slashdot.org] might not know what they are doing. Credentialism at it's worst.

    • absolutely correct. I feel for ya man. you were right.

      HOWEVER, they tried something new- it needs some revision obviously, but when they're done it could be something great.
      don't rain too hard on their parade- you might use this some day.

    • Hrm or more correctly that the vast majority of Profs dont have a clue about much anything in the real world.
      • The vast majority? Do you have figures? And aren't universities and colleges real-world entities? Isn't what goes on there just as "real" as what goes on in your office? Might as well say that the vast majority of [nurses|cab drivers|sysadmins|whatever] have no clue about the "real world". Perhaps you meant to say that your own experiences and context are the only "real" ones, and that other experiences and contexts are fantasies constructed by the less observant. Which suggests that your own grasp of reality is as tenuous as any academic's.

        • Isn't what goes on there just as "real" as what goes on in your office?

          Any place with a concept of "tenure" has no relationship to the "real" world.

          Just for the record, I agree with the guy. Not all college professors are clueless, but there is much, much truth in the old adage that "those who can, do. Those who can't, teach."

          • Re:Told you so. (Score:3, Insightful)

            by susano_otter ( 123650 )
            "those who can, do. Those who can't, teach."

            What about those who can teach? :p

            • What about those who can teach?

              That's just a myth they tell at NEA meetings. Kinda like Santa Claus and the Easter Bunny.

              Seriously, the best professors in college or higher that I have had have almost always been people burnt out on 'the real world', changing the phrase to "those who can do, those who can't, teach, those who teach well usetacould" (That last word is a real word. Just ask Jeff Foxworthy)

            • Re:Told you so. (Score:2, Funny)

              by Durrik ( 80651 )
              "those who can, do. Those who can't, teach."
              What about those who can teach? :p

              Well those that can teach, teach. Those who can't teach, teach teaching.

              Now say that 3 times fast, I dare you.

    • Re:Told you so. (Score:3, Insightful)

      by bahwi ( 43111 )
      Credentialism is bad.

      "Oh, it's ok. You don't have to wear a condom. I'm a professional. I do this all the time."

      - Yeah, uh-huh.

      • Re:Told you so. (Score:3, Interesting)

        by susano_otter ( 123650 )
        If by "credentialism" you mean "trusting an entity because of its credentials, rather than your own empirical proof of their trustworthiness, it depends. If the accrediting agency is known to be trustworthy, then entities bearing their credentials will, on the whole, be more reliable than non-accredited entities.

        For example: the Underwriters Laboratory. That "UL" tag on your microwave saves you the trouble of having to do your own exhaustive research on the manufacturer, plus thousands of man-hours testing each and every component many times over, just to make sure you're not buying a Deadly Microwave Oven Of Death.

        Of course, if you feel that credentialism is always bad, then you should probably evacuate your home, spend 20 or 30 years teaching yourself how to properly test home appliances (don't forget to start from fundamental principles, since you can't rely on anybody else's knowledge or expertise to help you speed up the learning process), and then go in and personally validate every electrical device you own. And you can give up selling your expertise to anybody else, since we have no reason to trust your own self-accreditation.

        I find it easier to research the trustworthiness of a few accrediting authorities, than to personally confirm the trustworthiness of everything around me. If the UL says it's safe, then those credentials are good enough for me. If the Elbonian Toursim Agency says it's safe, I'll want second opinion, though.
        • Certification of safety of products is a far cry from the acedemic world.

          (Ignoring the fact that the UL standards are pretty lax. As long your product isn't blatently dangerous, if you pay them, you can get their stamp of approval. I think you overestimate the rigor of their testing.)

          Anyway, university is a completely different thing. It's more about sucking up to those in power than actually learning anything. It's a disconnected and incestuous system of self-congratulary back patting and brown nosing. The real victims are those who sacrifice to go to school to actually learn, and those employers who erroneously equate degrees with real world skills.

          Of course, if, as an employer, you want someone well trained at brown-nosing and playing political games, then by all means choose someone with an extensive acedemic background. You won't be let down.
          • Of course, if, as an employer, you want someone well trained at brown-nosing and playing political games, then by all means choose someone with an extensive acedemic background. You won't be let down.

            That would explain most of the MBA's you run across. And doctors for that matter.

            (I am an MBA who works with doctors, so odds are I know more than you about this subject. 'You' indicating mindless moderators.)
          • Are you sure that you understand the true function of Underwriter's Laboritories? They don't guarantee that a product won't fail or that it's worth buying, just that if it does go bad it is very unlikely to start a fire or create a shock hazard when it does. Insurance companies don't care if you like the way your electric can opener works or not, they just want to be sure that they don't have to pay to replace your burned out kitchen.
        • No, if you followed his links and poked around a bit, the "credentialism" he spoke of was that other people believed the professors because they are university professors, although in a different field, they must know all the FCC regulations and be correct and that this person was not when he said "this probably violates some FCC regulations"(not an exact quote. Someone responded to him by saying "They are university professors so they know what they are doing and you don't know anything" (Not an exact quote, but quite close to what was actually said). That kind of credentialism.

          To go with your example, taking the UL tag, seeing it on your Microwave, and then seeing the same company has made (as an example) and has made a new web server, and saying "If the UL says their microwave is safe, then their web server must also be safe." even though it is in a different field, different product type, etc..

          That is what he meant. =)
        • I can't see how UL certification has anything whatsoever to do with credentialism [reference.com].

          GigsVT [slashdot.org] used the word correctly. Learn what words mean, not what you think they mean.

        • Good point.
          However this is more akin to trusting an MCSE cert to know more about fixing a cars breaks than a back yard macanic.

          Profs as a rule know the subject they teach rather well but enough don't that it's hard to trust a single proff won't make a mistake in his field.
          To make it sting the prof in question wasn't a radio expert so he's like your avrage slashdotter when sighting law. Maybe he knows and maybe he goofed.
    • Which proves once again, expertise in one field doesn't mean squat in another field. All too often we hear some fool say "I have a phd in [some random field], so you should listen to me when I discuss [some other field].". Uh, no.

      To the flamers, will you take the advice of a college professor of chemistry when it comes to setting up a secure network? Hell no! You probably wouldn't even listen to a computer science professor, either, because they usually don't have a clue about how things work in the 'real world.'

      To make it real simple for the more clueless:

      expertise in A != expertise in B
    • Yes, you were right but if the signal was separated into TX and RX. then a high antannae could legitimately be used for reception and a conventional antannae for transmission. The end result would still be a directional link, with longer than normal range.
      • Yeah, but what's the point of being able to recieve something you can't hit?

        The way the FCC rules are written, they do reward directional gain, you only have to reduce your power 1dbmw for each 3db in gain, so it does benefit you to have as high a gain as you can get. I think these rules are very reasonable, but easily violated if you aren't careful or well versed in this sort of thing.

        http://www.80211-planet.com/tutorials/print.php/ 14 28941
        If the antenna gain is at least 6 dBi, the FCC allows operation up to 4 watts EIRP. This is 1 watt (the earlier limitation) plus 6 dB of gain.

        For antennas having gain greater than 6 dBi, the FCC requires you to reduce the transmitter output power if the transmitter is already at the maximum of 1 watt. The reduction, however, is only 1 dB for every 3 dB of additional antenna gain beyond the 6 dBi mentioned above. This means that as antenna gain goes up, you decrease the transmitter power by a smaller amount. As a result, the FCC allows EIRP greater than 4 watts for antennas having gains higher than 6 dBi.

  • What the link is used for: (Score:4, Interesting)

    by dagg ( 153577 ) on Saturday December 21, 2002 @05:45PM (#4937536) Journal
    The link is used to carry data from a seismograph, data logger and Global Positioning System receiver. It cost about $3,000 to build and install.

    For that type of data, I would imagine that the reduced bandwidth will be just fine.

  • Curiosity (Score:3, Insightful)

    by Thatmushroom ( 447396 ) <Thatmushroom@NOSPam.mille352@purdue.edu> on Saturday December 21, 2002 @05:45PM (#4937538) Homepage
    These guys manage to create a 72-mile wireless link, truly an impressive feat, and do it with mostly computer guys? I'm not exactly certain, but it seems to me like they would have contacted a radio engineer at some point during the construction to assist them. Continuing with this hypothesis, shouldn't the radio engineer know the FCC guidelines and at least mention them so they wouldn't have to adjust the power?
    • Either recruiting a friendly radio amateur (radio engineer if you can get one) or investing the time to get their own licences would have been a good idea. Not only would they have more radio knowledge (or at least know where to find it), but they could operate in radio amateur frequencies with a much higher power limit.

      That said, it's been a while I tried out for mine (failed the 10 WPM Morse), and I have no idea what available frequencies are up there or how easy it would be to shift those transmitters -- but I bet that they could run a hell of a lot more power. (There are restrictions on the type of traffic, but that didn't seem to a problem in this case.)

      Honestly, if you can pass a Mickysoft "Engineer" exam, you can get your ham licence.

  • Why? (Score:2, Informative)

    by emptybody ( 12341 )
    (without reading the article of course}
    I ask a simple wuestion of the slashdot brain trust(tm)-

    Why?

    Why is building your own transmitter ilegal?
    Who decided that any government "owns" the radio spectrum?
    Who gives this organization such power to control the "airwaves"?

    Bah.

    • Re:Why? (Score:5, Informative)

      by GigsVT ( 208848 ) on Saturday December 21, 2002 @06:01PM (#4937593) Journal
      Why is building your own transmitter ilegal?

      It's not. Operating it in certain ways is illegal though.

      Who decided that any government "owns" the radio spectrum?

      The people own the radio spectrum, the government is "the people". At least in theory.

      Who gives this organization such power to control the "airwaves"?

      Consent of the people.

      If anyone could transmit at any power anywhere on the spectrum, no one would be able to use any non-microwave frequency. One guy with one poorly designed transmitter can easily obliterate several frequencies at once, rendering them all unusable, on a nearly worldwide scale.

      I suggest you listen in on CB frequencies for a while at night to see what sort of thing lack of regulation would bring to the spectrum as a whole.
      • Who decided that any government "owns" the radio spectrum?


        The people own the radio spectrum, the government is "the people". At least in theory.

        What makes radio frequencies so special that they require public ownership? And what makes a person think that public ownership really means owned by the "people"?

        The government owns a lot of land, facilities and equipment. I'll be damned if I try to use any of it myself. If I, as one of "the people", own everything that the government owns, I'd really like to take a hum-v for a spin, or cruise around in a jet plane. Not bloody likely.

        It would be more accurate to say that things owned by the "public" are really owned by no one, because no one is really allowed to use them. The only use is granted by someone who has rationalized themselves a form of power to make decisions for "the public". Seriously, how many times does doing things for "the public good" when they really mean "do this for others, not yourself".

        It seems a lot more rational to me if radio broadcasting ownership were just given to owners, who then could buy and sell those properties just like anything else. Or I guess we could just continue to let the government pick the privelidged and favorites.

        The last great act that the government did as far as ownership goes was the Oklahoma land rush. That's the way that "unowned property" should be taken care of, not some institutionalize nepotism.

        If that were the case, the innovator in this story could have just asked the people that he would be "interfering with" for permission. Might have need to buy or lease a couple frequencies for a while.

        Instead, he's just turned it down considerably. I'd wager pretty good money that the capacity he gave up is now being used by "no one", rather than another one of "the public" who "own" the radio frequencies.

        • As someone who is mostly Libertarian, I hear where you are coming from, but radio really is unique.

          There is only one EM spectrum. There will always only be one. With proper management, we can get a whole lot more good out of it than without.

          You propose a free market in frequencies. Well, how exactly do you quantify a frequency? HF frequencies are world wide. VHF/UHF are generally regional, but the range depends on dozens of factors.

          How exactly would one make out a "deed" for a frequency? Would special civil courts need to be set up to determine the inevitable highly technical disputes? A world court for HF and lower? If so, you've only shifted the regulation, not eliminated it, and in the process, made it impossible for anyone other than the very rich to gain access.

          I don't think our current system isn't too bad. There are some definite broken spots that are stifling new technology, and controlling the flow of information, but overall I think the system is working, and other than allowing some questionable mergers in the mass media markets, I think the FCC has at least tried to make some very good decisions in the last several years (think LPFM, which was gutted by the Senate, but advocated by the FCC).

          • There maybe only one EM spectrum, but there are infinite uses of that EM spectrum as technology and ability increase.

            A property rights system would need to be implimented, but it does not need much additional "special" legislation because it's not a "special" property. A quick observation on the futures market (and other derivitives) shows just how smoothly and peacefully the market can handle abstract ownership rights.

            A "deed" for a frequency would simply need to be an area specific broadcast right. There's no problem "quantifying" frequencies because we measure and quantify frequencies every day using almost simple equipment.

            It could be similar to the way that land is divvied up. As technology increases and our ability to utilize the EM spectrum increases, the effective land mass of existing deeds would increase. It would then just be a matter of allowing a deed owner to split is property into smaller ranges and sell them as he sees fit.

            I urge you to look past the propeganda and current status quo as a foundtation for rational thought on the subject. Just because we've been trained to believe that EM frequencies are "special", doesn't mean that they are insurmountable for a market system. A free market system always puts the greatest use out of the smallest resource, regardless of how abstract that resource is.

            There would indeed be highly technical disputes that our current system isn't equiped to handle. But our current system isn't equiped to handle any high tech dispute... just look at the DMCA and the incroaches on your personal liberties that take place every day in the more technical aspects of our lives.

            I would venture to say that the inability of government to keep up and effectively manage things of advanced technical complication and significance is the best possible reason to remove the complete government control of a medium.

            We take for granted the current solution of EM frequency management because no one is free to come up with a better one.

            Einstein said, "Everything that is really great and inspiring is created by the individual who can labor in freedom."

            That theory holds true for concepts like organization and management. Without the armed guards enforcing the status quo, someone with a brain can think up a better way to handle and manage the EM spectrum property. Probably with some scheme or idea that is so simple and elegant that our children would think that anything else is infantile.

      • I suggest you listen in on CB frequencies for a while at night to see what sort of thing lack of regulation would bring to the spectrum as a whole.

        Can you tell me why I sould compare amplitude modulated voice comunications on a single frequency, technology much like Marconi used 100 years ago, to freqency hopping, digital communications? Asside from the use that people get out of CB and the usless FCC restrictions, these two unlicensed freqency specturms have little in common. What do you get out of FCC regulations? All I get is really bad broadcast TV and radio.

        Have some juice and cookies, it will make you feel better when people disagree with you. It's not a flame, it's a different point of view.

        • Asside from the use that people get out of CB and the usless FCC restrictions, these two unlicensed freqency specturms have little in common. What do you get out of FCC regulations?

          Did you think I was calling for heavier regulation of 802.11b? My comment wasn't directed at 802.11b at all. I think the level of regulation there is just fine. The original poster was questioning the very existance of the FCC.

    • it's simple (Score:2, Insightful)

      by SweetAndSourJesus ( 555410 )
      If you don't regulate it, people go nuts. People decide they need to broadcast at 25,000 watts from their garage. Frequencies get jammed up so bad that nobody can talk. Nobody wants that, so we have a government agency to keep it under control.

    • Why. (Score:4, Informative)

      by Theaetetus ( 590071 ) <theaetetus,slashdot&gmail,com> on Saturday December 21, 2002 @06:16PM (#4937645) Homepage Journal
      Government doesn't 'own' the radio spectrum - it regulates it. Who gives them the power to do so? We do, by having a government in the first place.

      Building your own transmitter is perfectly legal, and kinda fun. However, turning it on and broadcasting above the LPFM limits is illegal because you're interfering with someone else's transmission.

      The reason these rules exist (at least theoretically) are to prevent any and every organization from building hundred-thousand watt transmitters (or more!) and broadcasting their message willy-nilly... such as the KKK, NAMBLA, the RIAA, Coca-cola, etc. In order to get a license to broadcast, broadcasters must show signifigant community need, they have to have a local point-of-presence for the public to come in to see them, they must maintain public records, they must broadcast community interest messages (ads for local businesses, PSAs, etc.)
      These rules have been enforced a little bit loosely lately, but that's starting to step up - the FCCs enforcement budget was drastically increased this past year.

      Stop and consider what would happen, though, if the FCC didn't exist - companies would start broadcasting their advertisements non-stop, and if a competitor tries to broadcast theirs, the first one simply brings up the power on his transmitter and jams the other one out. Pirates (who, of course would not be pirates if there was no FCC) wouldn't have a chance, as there would be so much radio being broadcast that there wouldn't be anywhere they could find to put in a low power transmitter (and before you think about a high power one, keep in mind how expensive they are). After a short time of this, people would stop listening to the radio, stop watching TV, etc. There would be no reason to do so, as there would be nothing of entertainment or educational value. Radio and television would then die out.

      In essence, your question is very much the same as saying "why is carrying a gun around illegal? Who decided that any government could make laws telling me I can't carry a gun? Who gives them such power to enforce 'laws'?" The reason why is that it would be disruptive to society otherwise - that's why the FCC is there.
      We may not like 'em, but they're much better than the alternative.

      -T

      • If you build a transmitter, you will have the same rights as someone who bought a transmitter. There is no difference between buying and building one according to FCC regs. However, if you build one and it does not meet FCC regs (transmits outside of your channel, too much power, bad signal, etc) then you're in trouble. Also, on some channels, your radio might be required to be certified by the FCC (such as the FRS frequencies).

        Also, LPFM is not license-free. I think what you're referring to is that the FCC permits very low-power devices to transmit on parts of the broadcast band (I believe the regs say that 100 yards is the maximum distance). LPFM is a broadcast service with different power limits (100W or so), requires a license, and is only available in a couple of states.
        • However, if you build one and it does not meet FCC regs (transmits outside of your channel, too much power, bad signal, etc) then you're in trouble.

          'Trouble' being a relative thing, the FCC regs acknowledge that hobbyists may not have the necessary equipment to test their home-built transmitter's total power output. They are expected to employ best engineering practices to ensure that their device probably doesn't violate the regs. The first step of "trouble" you'd get in for a home built transmitter that tramples everybody's signal is someone showing up at your door telling you to turn your transmitter off.
      • >>why is carrying a gun around illegal?

        It is not - at least where I live.

        >>Who decided that any government could make laws telling me I can't carry a gun?

        Where I live we have specifically prevented the government from passing such laws.

        >>The reason why is that it would be disruptive to society otherwise - that's why the FCC is there. We may not like 'em, but they're much better than the alternative.

        Except that people having the legal right to carry (without a permit) and conceal (with a permit) is one factor in substatially reduced crime rates.

        As for the FCC-they have over-stepped their bounds by making it too costly and therefore impossible for the average person to enter the broadcast market (radio or Internet). They have succummed to the political lobbyists.
      • In essence, your question is very much the same as saying "why is carrying a gun around illegal? Who decided that any government could make laws telling me I can't carry a gun? Who gives them such power to enforce 'laws'?" The reason why is that it would be disruptive to society otherwise - that's why the FCC is there.

        That is a very poor analogy since in the vast majority of the US mainland it is perfectly legal to carry a gun.

        • Re:Why. (Score:1, Troll)

          by Spruitje ( 15331 )

          That is a very poor analogy since in the vast majority of the US mainland it is perfectly legal to carry a gun.

          And which proves that banning guns also brings down crime rates.
          There are around 2 million people in prison in the US (on a population of around 265 million).
          Compare this to for instance to the Netherlands with 16 million people and only around 40.000 people in prison and it's very easy to see that due to the fact that it is legal to carry a gun in the US also means that there is more crime and thus more people in prison.
          It so simple...

          • There are around 2 million people in prison in the US (on a population of around 265 million).
            Compare this to for instance to the Netherlands with 16 million people and only around 40.000 people in prison and it's very easy to see that due to the fact that it is legal to carry a gun in the US also means that there is more crime and thus more people in prison.
            It so simple...

            Man, such twisted facts. A very large percentage of the people in prision in the US are due to drug violations, a lot of them minor, not violent crimes. The Netherlands has a very loose drug policy. Right statistics, wrong conclusion. The conclusion is that the US should take a look at this "war on drugs" and the damage it does to our society.
          • It is simple for such a simple mind.
            Maybe you just need to consider this is NOT the Netherlands.
          • That is a very poor analogy since in the vast majority of the US mainland it is perfectly legal to carry a gun.
            And which proves that banning guns also brings down crime rates.

            It proves nothing of the sort. The United States is a big place. Much of the country is undeveloped, or rural. Most of these areas have the least restrictive gun laws, because there isn't any reason to restrict them. Those areas with very high population densities (cities) often have the most restrictive gun laws. They also have most of the murders. Should I then conclude that restrictive gun laws cause murders?

            BTW, the reason we have so many convicts, is because we treat drug use (and the associated spilloff of crimnal activity) as a crime. Please factor that into your calculations the next time when you want to compare apples with oranges.

    • Re:Why? Because. (Score:4, Interesting)

      by susano_otter ( 123650 ) on Saturday December 21, 2002 @06:25PM (#4937679) Homepage
      The government doesn't "own" the radio spectrum; it regulates it.

      In theory, the government's power to control the "airwaves" was granted by the people, by way of their elected representatives--you and me, that is (or in this case, our parents and grandparents). In practice, of course, giving and taking power from the government is much more complicated and frustrating.

      The reasons for having a regulatory body for the radio spectrum should be obvious. The best reason I can think of offhand is airplanes. Airplanes rely heavily on communication via radio waves for safe and accurate travel. If there is no regulation (which might be though of as standards + enforcement), then no airplane can know with any certainty any of the important information:

      What band to use to communicate with air traffic control?

      What band to use to communicate with guidance beacons?

      What band to use to communicate in an emergency?

      Assuming you've got a good idea of which band to use, how can you guarantee that any of these bands will be available?

      Will the guidance beacon band be overridden by a nearby private transmitter?

      Will pranksters or malefactors transmit false traffic control instructions over the air traffic control band?

      Will high-powered transmissions from nearby (unregulated) transmitters inadvertently disrupt the plane's avionics during takeoff or landing?

      Without standards that everybody agrees on, and without proper enforcement of these standards, air travel would involve crashing planes into buildings on a regular basis. And that's just one of the many reasons why regulation is a good thing.

      Transmittors who think that regulation is an "opt-in" thing, and that they're somehow entitled to ignore it if they want to, ruin it for everybody else. Every use of the radio spectrum that you enjoy in your daily life is made possible by regulation. It's why your cellphone doesn't pick up Mexican radio stations. It's why your radio-dispatched taxi arrives on time to pick you up. It's why your satellite TV gives you a clear image, without static from nearby 802.11b nodes.

      Nobody "owns" the radio spectrum, but we all use it. Regulation helps make sure that it remains useful. You and I probably agree that the regulations aren't always beneficial to citizens, but ignoring them won't make things any better for anyone.

      If none of this is obvious to you, then how can we possibly trust you to voluntarily play nice with others? And if we can't trust you to play nice, then we're left with two options: abandon any hope of ever using the radio spectrum for anything at all, or else enforce the standards and keep the spoilers out of the spectrum.

      Which option would you vote for?
    • Why is building your own transmitter ilegal?

      As long as you follow the codes & can prove that you know what you're doing, I don't think that it is.

      Who decided that any government "owns" the radio spectrum?

      We did. The governments of the world exist to protect their populations from foreign powers, to act in the best interest of their populations, and to settle disputes between members of their population.

      The radio spectrum is a place where, if left unchecked, would be rather difficult to use. Government regulation and control is, oddly enough, the perfect answer for this, although the form of said control could use a bit of revision.

      Who gives this organization [the FCC] such power to control the "airwaves"?

      The Congress and President of the United States of America, under powers approved by the Supreme Court and endowed into them by the citizens and electoral college of the United States.

      If the question of "should government regulate airwaves" is answered in the affirmative, the next step is to form a new entity that acts very much as a "industry association" to do the actual regulation.

      Anarchy leads to no infrastructure and rule of might, as opposed to rule of right or rule of law. Though they aren't ideal yet, the governments of the world DO serve a necessary purpose, and this is one of them.
    • > Why is building your own transmitter ilegal?

      Because, much like building your own braking systems, it presents a hazard to the general public if done incorrectly.

      > Who decided that any government "owns" the radio spectrum?

      The radio spectrum is a public resource. We (the voters) depend on government agencies to regulate the use of it, to ensure that a limited resource is available to as many users as possible, as consistently as is reasonable.

      >Who gives this organization such power to control the "airwaves"?

      The RF spectrum is just like the visible light spectrum, the audible spectrum. I may enjoy the sound of a chevy small-block with open headers, but if I fire it up at 4am, the neighbors are going to take exception, even though all I'm doing is making "waves in the air".

      When computers first hit the market, the RF emissions from them were pretty horrible; turning on an Apple II pretty much killed radio and TV's within 50 feet.

      That said, one would assume that regulation should theoretically *prevent* abominations like broadcast television.

      That said.
    • Why? Because the aliens are coming...

      Why is building your own transmitter illegal? Because when the aliens attack we want to charge them an hourly fee for communicating with eachother for the last 70 eons, putting them in financial ruin, which makes it impossible to run their armies of aliens, therefore thwarting the attack. We are the Victor!

      Who decided that any government "owns" the radio spectrum? The people who want to thwart the alien's attacks!!!

      Who gives this organization such power to control the "airwaves"? What they really want to do is charge you money or lock you up! That way they have prior cases to back up their suit against the attacking aliens!

      /strangeness...

      No really, I have no idea why. Maybe because they're capitalists and therefore they're evil at heart because they're driven by money. [greed]
    • I have a question:

      Since the signal strength of a single transmitter is limited wouldn't it be possible to build two transmitters very close to each other (possibly owned and operated by different people) transmitting on slightly different frequencies and thereby increase the effective bandwidth? Or would they interfere too much?

  • This isn't really related to 802.11, but while we're on the topic of FCC, I heard that DSL is limited to 1.5 Mb/s in the USA. Is this true? I'm in New Zealand and I'm currently connected at a little over 4.4 Mb/s, with a theoretical maximum of 8. If what I heard is true, I wonder what the reason is? Sorry about the OT, I've been wondering about this for a while and saw this as a chance to jump in and ask :)
    • DSL faster than 1.5Mbps is available in the US.
    • DSL is limited in the United States due to concerns that the signal will bleed over in legacy telco equipment, thereby rendering many older phone systems obsolete. The baby bells wanted to push this regulatory measure through to enable her to make all equipment, even older Phone systems, work with the extra measure of having DSL on the line.

      Keep in mind that most DSL equipment actually operates several thousand hertz higher than what you can physically hear.

      It is quite all right though, as I worked for a DSL acompany, I got to test equipment. Imagine pure internet joy at 3 MB up and down with a class C of Public IP's :) (Two DSL lines channel bonded together through a netopia router)
      • What legacy telco equipment operates at what frequencies that would make it susceptible to interference from DSL? Isn't DSL basically a hypersonic electrical signal running over the "last mile" wiring between the subscriber and the central office and then patched around the central office's dialing switches back over last mile wiring to the ISP? Since the only other signal on last mile wiring is at voice frequencies, and stuff attached to that last mile wiring usually has low pass filters, how would DSL cause interference?

  • Still not too shabby (Score:4, Insightful)

    by coolgeek ( 140561 ) on Saturday December 21, 2002 @05:58PM (#4937581) Homepage
    300Kbps free transmission for 72 miles is fine in my book.
  • This could be the thing I have been looking for. I'm trying to bridge a 12KM gap here.
    J.
    • I do not know what they are using (as far as I know, unamplified 802.11b is 30 mW).

      But, if you can see the other point (clear line of sight), 12 Km can be done with standard WiFi (802.11b) cards with reasonnable antennas (paraboles, horns, SlottedWaveGuide,... )

      12 Km is a little bit out of range for tin cans [seattlewireless.net], but we achieved 9.5 km with ...CardboardHorn [seattlewireless.net]s ;-)
      Yet a lighter version : the TetraPak horn [seattlewireless.net] is not bad.

      But, to be sure, use paraboles like in one of the first long shots [oreillynet.com].

      ...And remember: You need 6 dB to double the distance (whatever it is).

  • Restrictions have reasons (Score:3, Insightful)

    by flopsy mopsalon ( 635863 ) on Saturday December 21, 2002 @06:17PM (#4937649)
    The FCC doesn't pass regulations for no good reason. , so as long as folks use after-market antennas and no one files any complaints, the FCC isn't looking to imply cut back on allowable bandwidth. Wide bandwidth spectrum can be used by many users for diffeent reasons. For example, in urban areas, some of the users may be hospitals utilizing heart monitors.

  • Herein Lies the Problem (Score:5, Insightful)

    by zentec ( 204030 ) <zentec AT gmail DOT com> on Saturday December 21, 2002 @06:47PM (#4937749)
    The owner is reported saying that: "any violation of the power limits was unintentional and resulted from the fact that the personnel working [on it] primarily have expertise in computers and not radio technology." That says it all. A bunch of computer people playing with RF; no knowledge of Part 15 rules, no concept of RF. Really, if the FCC is going to assign new frequencies for wireless networking, we owe it to ourselves to become acquainted with the technology and the rules thereof. The last thing that anyone needs is to turn 802.11 into another RF wasteland like CB radio.

    • Re:Herein Lies the Problem (Score:1, Funny)

      by Anonymous Coward
      funny, i didnt see you at the nuclear power plant figuring out how they get power to your house...
    • "...the personnel working [on it] primarily have expertise in computers and not radio technology."

      Sounds like most local / regional wireless ISP's.. Or rather, dialup ISP's that try/tried wireless as a cheap alternative to DSL.
    • Really, if the FCC is going to assign new frequencies for wireless networking, we owe it to ourselves to become acquainted with the technology and the rules thereof. The last thing that anyone needs is to turn 802.11 into another RF wasteland like CB radio.

      That's why we have licensing for radio operators: people are supposed to demonstrate a minimum amount of knowledge before they go around hacking radio transmitters.

      The real problem is that the law doesn't require licenses for modifications to radio equipment in many cases, and that when they do, people don't know about it and it doesn't get enforced anyway.

      For 802.11b and other uses of the "unlicensed" 2.4G and 5G bands, the rules should really prohibit the kinds of modifications to antennas that people are making--operation of those devices by unlicensed operators should only be permitted with the original antennas, and they should be subject to FCC review. Otherwise, we are inviting abuses: if someone aims one of those things at your house, your own equipment may stop working and you won't even be able to figure out why.

      I think the rules should also prohibit the use of unlicensed spectrum by B2B or B2C services; extensive use of 802.11b by for-pay ISPs and voice providers may well render the bands useless for their originally intended purpose. Companies wanting to derive a profit by providing services should pay for their own bandwidth.

  • Wouldn't it be nice if I could pick up a simple kit that would get me a 2 to 5 mile radius around my base station. One that didn't require me to hold a directional antenna and GPS to properly aim it.

    Maybe setting up N*(directional antennas) with 360/N degrees coverage would be better?

    Or put a passive "repeater" WPOP into every car. Put an omnidirectional antenna on the roof and we could have WPOPs all over the interstate.

    I would run one if it let me surf in traffic. And believe me, there will always be traffic jams. Bounce your signal through a few cars till you get to someone's excess bandwidth landline based system.

    Heck, the phone company could put a base station at every rest stop with a payphone. Just pull into the parkinglot to get better bandwidth.

    If you make every box also have a caching proxy (squid) and a large harddisk (IBM 150Gb =200$) you would be able to do what AOL did to save bandwith costs. CACHE EVERYTHING

    Of course you would have to encrypt all outgoung data and use SSL on sites that matter.

    Made in the shade. Partners? Anyone?
  • I think I'd like to spend some time trying to come up with a system designed to fry computers belonging to all the twits who are filling our collective air with their high energy EM pollution.

    Directional, non-directional, I don't care too much. I want to be the guy with the portable EM Pulse generator. You like EM? I'll give you EM.

    People seem to take pride in saying things like, "I'm useless without my cell phone and PDA!"

    And you're pretty useless with it, too, actually. Stick a joker like that in a forest with a knife, two matches and a fishhook and see how long he'd last. Pathetic, or at least the precursor to something terribly Darwinian in scope. . .


    -Fantastic Lad "--Look Ma! 5000 fried cell phones and their owners wandering around like so many headless chickens!" "Stop teasing the sheeple, junior."

    • Are you saying that people who don't say things like "I'm useless without my cellphone and PDA" *would* last in a forest with a knife, two matches and a fishhook?
    • My cellphone has gotten me out of many tough spots before, and it also frees me up to do more things. Im only 16, so it makes communicating with my parents really easy when im not at home. Went to the dance, and now I want to go out and have dinner with my friends? No problem! I just call them and tell them. Its amazing that you posted on a geek website with anti-electronic sentiments. Id like to see you survive without your car... or ac/heat in your house... or without your TV... or without lighting... or indoor plumbing. In any case, you will never have to survive withtout those things, the same way people will never have to survive without thier cellphones and PDAs. Oh yeah, and you can have my PDA when you pry it from my cold, dead hands (or buy me and upgrade :) ).
      • -And that was my grumpy side. Normally I don't blast like that, but wrong sides of beds and all. . .

        A few points, though. . .

        * I don't have a car and I don't want one. Bike, walk, bus, and make the effort to live near your work place. -I recognize that some people don't have that option, but far, far too many do and are simply lazy clouts.

        * I can't stand TV, and I don't understand anybody who can, especially these days when the propaganda and social molding isn't even hidden anymore.

        * I don't have AC. A fan and a teeshirt are just fine, thanks. AC is a relatively new thing anyway. A luxury, I'd dare to say. Though I would be in a spot without my heat. But I did mention the two matches, didn't I. . ?

        * Lighting and indoor plumbing are also things I grew up with and would miss. But then neither of them emit EM in way demonstrated to directly alter brain chemistry.

        When I was your age, I managed to survive without a cell phone. In fact, I did more than just survive. I and all the other kids thrived. We were active, healthy, smart and happy. Life was good. In fact, by all indicators, life was a LOT better.

        Your technology is your cage. But you are also the keymaster. The crime is that you have been fooled into limiting your own choices.


        -Fantastic Lad

  • Radiated field works by the square of the EIRP.That is, to double the field, you need to 4X the power. Therefore, reducing the power to 1/4 of what it was exactly halves the field (-6db). They probably could make this up with a good, low noise (GaS FET) receive preamp. The worst thing it does is reduce their fade margin by 6 db as well. By the way, I know of many companies that routinely get 50-100 mile shots using the 5 gig unlicensed band and 10 foot dishes.
  • so now, you could be 72 miles from you provider and still get a 300kbps link, wonder how many providers are watching this.
    • It's not as commercially viable as you may think, though. At least, not unto itself - that's why there's WAP and cellphones. Note it's been a while since I read up on RF physics - I suppose I should if I'm ever going to upgrade my ham license. Anyway, if I remember correctly, microwave is very much line of sight - even more so than VHF or UHF. In short, it hits an object and dissipates into heat, regardless of whether it's concrete or hamburger. It's what makes your microwave oven so effective.

      So now imagine having to put up a whole new slew of repeaters, sattelites, etc., etc., ad nauseam to get your wireless TCP/IP traffic around the world. I would propose that the only viable way of doing this is using digital sattelite TV - but on the other hand, DirecTV DSL is closing up, so there you have it.

  • 70 some-odd mile internet range? That would cut out a lot of potential profit from a market for some companies...
  • "a 72-mile 802.11b wireless link... the link power has been reduced by 75% to comply with FCC regulations for the 2.4-GHz band..."the personnel working [on it] primarily have expertise in computers and not radio technology.""

    So how much power were they putting out in the 2.4 GHz band again? Could they pop microwave popcorn? Will they ever be able to have children?
  • There's point-to-point microwave gear for that sort of thing. 802.11x, which is a wireless LAN system, is the wrong tool for long-haul links.

    If you get an FCC license for your fixed microwave link, which isn't a big deal in most areas, your link goes in the FCC database, and you're protected from interference from future links.

  • All you need is a ham radio license and to reclassify this gear as part 97. You can then have up to 100W into the antenna and ERP much higher. Check this link: http://www.qsl.net/kb9mwr/projects/wireless/Ham_Et hernet_GBPPR.pdf to find out more. If this is just expermintation and has nothing to do with business then this would be what they need.
    (make sure you check out the section of power limits in that above link, 100W at 2.4Ghz into 24dBi dish = 25118.8 W EIRP and still perfectly legal. The FCC makes the rules but luckily they make it easy to do what these people want to do, again if its not business related that is.

    -Tom
    • I thought this was pretty ridiculous when I first read it, so I did some research and read up on the part 15 and part 97 regs... but you're right, if you have a radio license, part 15 regs don't apply to you, and part 97's do. And you could, theoretically at least, crank the power at the transmitter up to 100W. One thing stopping you is part 97 section 313(a): An amateur station must use the minimum transmitter power necessary to carry out the desired communications. 100W is only perfectly legal if that is how much you need. I'm pretty sure if you work the numbers you could show that no two line of sight points within 50km of the surface of the earth would require that much power.

      So even with a license, they would probably have to keep the power down to 250mW unless they could show they needed more than 300kbps. The FCC is far less lenient with licensed radio operators than amateurs and cranking the power up well above the minimum necessary could result in your licensed being revoked.

      Also to fall under part 97, while transmitting you must have a control operator manning the equipment, or if you have an automatically controlled station your bandwidth limitation is 500Hz (I'm not sure that is even possible with 2.4GHz).
      • Your right about power, if you go over 1W you do need to have a system in place to automatically use the lowest power neccessary(there are linear amps that can do this but are quite expensive.) I didn't mean to say everyone jump out and use 50-100W, just that they wanted to use 1W and that would be more then exceptable since 100W is the limit. All hams try to use the least power possible. Glad to see you did read up on this though, in my area some hams do use 802.11 for radio, but again, we use MUCH less then the max power.

        -Tom

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